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Background: Rickettsia and related diseases have been identified as significant global public health threats. This study involved comprehensive field and systematic investigations of various rickettsial organisms in Yunnan Province., Methods: Between May 18, 2011 and November 23, 2020, field investigations were conducted across 42 counties in Yunnan Province, China, encompassing small mammals, livestock, and ticks. Preliminary screenings for Rickettsiales involved amplifying the 16S rRNA genes, along with additional genus- or species-specific genes, which were subsequently confirmed through sequencing results. Sequence comparisons were carried out using the Basic Local Alignment Search Tool (BLAST). Phylogenetic relationships were analyzed using the default parameters in the Molecular Evolutionary Genetics Analysis (MEGA) program. The chi-squared test was used to assess the diversities and component ratios of rickettsial agents across various parameters., Results: A total of 7964 samples were collected from small mammals, livestock, and ticks through Yunnan Province and submitted for screening for rickettsial organisms. Sixteen rickettsial species from the genera Rickettsia, Anaplasma, Ehrlichia, Neoehrlichia, and Wolbachia were detected, with an overall prevalence of 14.72%. Among these, 11 species were identified as pathogens or potential pathogens to humans and livestock. Specifically, 10 rickettsial organisms were widely found in 42.11% (24 out of 57) of small mammal species. High prevalence was observed in Dremomys samples at 5.60%, in samples from regions with latitudes above 4000 m or alpine meadows, and in those obtained from Yuanmou County. Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis were broadly infecting multiple genera of animal hosts. In contrast, the small mammal genera Neodon, Dremomys, Ochotona, Anourosorex, and Mus were carrying individually specific rickettsial agents, indicating host tropism. There were 13 rickettsial species detected in 57.14% (8 out of 14) of tick species, with the highest prevalence (37.07%) observed in the genus Rhipicephalus. Eight rickettsial species were identified in 2375 livestock samples. Notably, six new Rickettsiales variants/strains were discovered, and Candidatus Rickettsia longicornii was unambiguously identified., Conclusions: This large-scale survey provided further insight into the high genetic diversity and overall prevalence of emerging Rickettsiales within endemic hotspots in Yunnan Province. The potential threats posed by these emerging tick-borne Rickettsiales to public health warrant attention, underscoring the need for effective strategies to guide the prevention and control of emerging zoonotic diseases in China., (© 2024. The Author(s).)

Background: Brucellosis is a zoonotic affliction instigated by bacteria belonging to the genus Brucella and is characterized by a diverse range of pervasiveness, multiple transmission routes, and serious hazards. It is imperative to amalgamate the current knowledge and identify gaps pertaining to the role of ticks in brucellosis transmission., Methods: We systematically searched China National Knowledge Infrastructure (CNKI), WanFang, Google Scholar, and PubMed on the topic published until April 23, 2022. The procedure was performed in accordance with the Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The selected articles were categorized across three major topic areas, and the potential data was extracted to describe evidence-practice gaps by two reviewers., Results: The search identified 83 eligible studies for the final analyses. The results highlighted the potential capacity of ticks in brucellosis transmission as evidenced by the detection of Brucella in 16 different tick species. The pooled overall prevalence of Brucella in ticks was 33.87% (range: 0.00-87.80%). The review also revealed the capability of Brucella to circulate in parasitic ticks' different developmental stages, thus posing a potential threat to animal and human health. Empirical evidence from in vitro rodent infection experiments has revealed that ticks possess the capability to transmit Brucella to uninfected animals (range: 45.00-80.00%). Moreover, significant epidemiological associations have been found between the occurrence of brucellosis in animals and tick control in rangelands, which further suggests that ticks may serve as potential vectors for brucellosis transmission in ruminants. Notably, a mere three cases of human brucellosis resulting from potential tick bites were identified in search of global clinical case reports from 1963 to 2019., Conclusions: It is imperative to improve the techniques used to identify Brucella in ticks, particularly by developing a novel, efficient, precise approach that can be applied in a field setting. Furthermore, due to the lack of adequate evidence of tick-borne brucellosis, it is essential to integrate various disciplines, including experimental animal science, epidemiology, molecular genetics, and others, to better understand the efficacy of tick-borne brucellosis. By amalgamating multiple disciplines, we can enhance our comprehension and proficiency in tackling tick-borne brucellosis., (© 2024. The Author(s).)

Background: Ticks are hematophagous parasites that transmit an extensive range of pathogens to their vertebrate hosts. Ticks can destroy invading microorganisms or alleviate infection via their rudimentary but orchestrated innate immune system. Antimicrobial peptides (AMPs) are important components of tick innate immunity. Among these humoral effector molecules, defensins are well-studied and widely identified in various species of Ixodidae (hard ticks) and Argasidae (soft ticks). This review was aimed at presenting the characterization of tick defensins from structure-based taxonomic status to antimicrobial function., Main Text: All published papers written in English from 2001 to May 2022 were searched through PubMed and Web of Science databases with the combination of relevant terms on tick defensins. Reports on identification and characterization of tick defensins were included. Of the 329 entries retrieved, 57 articles were finally eligible for our scoping review. Tick defensins mainly belong to the antibacterial ancient invertebrate-type defensins of the cis-defensins superfamily. They are generally small, cationic, and amphipathic, with six cysteine residues forming three intra-molecular disulfide bonds. Tick defensins primarily target membranes of a variety of pathogens, including Gram-positive and Gram-negative bacteria, fungi, viruses, and protozoa. Since tick defensins have a high degree of variability, we summarize their common biological properties and enumerate representative peptides. Along with the various and potent antimicrobial activities, the role of tick defensins in determining vector competence is discussed., Conclusions: Due to their broad-spectrum antimicrobial activities, tick defensins are considered novel candidates or targets for controlling infectious diseases., (© 2022. The Author(s).)

Background: Toxoplasma gondii infection is mainly caused by ingestion of water or food that is contaminated with oocysts excreted by cats, or by eating raw meat containing T. gondii tissue cysts. However, oral transmission does not explain the common occurrence of toxoplasmosis in a variety of hosts, such as herbivorous animals, birds, and wild rodents. Little information exists on the maintenance of T. gondii parasites in nature and routes of transmission to domestic and wild animal hosts. Therefore, this study evaluated the role of Haemaphysalis longicornis ticks in the epidemiology of toxoplasmosis., Methods: The real-time polymerase chain reaction (qPCR) technique was used to detect the presence of T. gondii DNA in ticks collected from the field. To observe the amount of dynamic changes of T. gondii in the tick's body and its infectivity, microinjection of green fluorescence parasites was performed. Under laboratory conditions, we evaluated if H. longicornis ticks were infected with T. gondii and their potential to transmit the infection to other hosts using traditional parasitological methods coupled with molecular detection techniques., Results: The infection rates of T. gondii parasites among field-collected adult and nymph H. longicornis ticks were 11.26 % and 5.95 %, respectively. T. gondii can survive and remain infective in a tick's body for at least 15 days. We found that blood feeding of infected ticks did not transmit T. gondii to hosts, however, ingestion of infected ticks may be a transmission route between ticks and other common hosts., Conclusion: The T. gondii infection in ticks could serve as a reservoir for toxoplasmosis transmission.

Background: Toxoplasma gondii infection is mainly caused by ingestion of water or food that is contaminated with oocysts excreted by cats, or by eating raw meat containing T. gondii tissue cysts. However, oral transmission does not explain the common occurrence of toxoplasmosis in a variety of hosts, such as herbivorous animals, birds, and wild rodents. Little information exists on the maintenance of T. gondii parasites in nature and routes of transmission to domestic and wild animal hosts. Therefore, this study evaluated the role of Haemaphysalis longicornis ticks in the epidemiology of toxoplasmosis. Methods: The real-time polymerase chain reaction (qPCR) technique was used to detect the presence of T. gondii DNA in ticks collected from the field. To observe the amount of dynamic changes of T. gondii in the tick's body and its infectivity, microinjection of green fluorescence parasites was performed. Under laboratory conditions, we evaluated if H. longicornis ticks were infected with T. gondii and their potential to transmit the infection to other hosts using traditional parasitological methods coupled with molecular detection techniques. Results: The infection rates of T. gondii parasites among field-collected adult and nymph H. longicornis ticks were 11.26 % and 5.95 %, respectively. T. gondii can survive and remain infective in a tick's body for at least 15 days. We found that blood feeding of infected ticks did not transmit T. gondii to hosts, however, ingestion of infected ticks may be a transmission route between ticks and other common hosts. Conclusion: The T. gondii infection in ticks could serve as a reservoir for toxoplasmosis transmission. [ABSTRACT FROM AUTHOR]

Background: Babesiosis is an emerging tick-borne zoonotic infectious disease. Babesia microti is responsible for most cases of human babesiosis globally. It is important to investigate the prevalence of B. microti in the mammalian host population of a specific region in order to elucidate mechanisms of pathogen transmission and to define geographic areas where humans face the greatest risk of exposure. The aim of this study is to understand the prevalence and genotypes of B. microti in the small mammals that are found in Beijing, China., Methods: We trapped small mammals from all of the 16 urban, suburban, and outer suburban districts of Beijing during the years 2014, 2017 and 2018. Genomic DNA was extracted from the heart tissues individually and the Babesia 18S rRNA gene was detected by PCR. The genotypes of B. microti were identified based on sequence alignments and phylogenetic analysis. The morphology of the parasites was observed under light microscopy. The risk factors were analyzed statistically based on both univariate analyses and multivariate logistic regression., Results: A total of 1391 small mammals were collected. Positive infection of B. microti was detected in 12.1% (168/1391) of small mammals from 15 out of the 16 districts. Both Kobe-type and U.S.-type B. microti, accounting for 9.5% and 2.7%, respectively, were identified. Classic diverse morphologic forms of B. microti were observed. Specific types of ecological habitats including shrub areas, broad-leaved forest, and cropland were revealed to be risk factors associated with B. microti infection., Conclusions: This study demonstrated the wide prevalence of B. microti infection in eight species of small mammals in Beijing, with Kobe-type more prevalent than U.S.-type. This study provides fundamental information for the development of informed prevention and control measures by public health authorities; the data gathered indicates a need for further monitoring of both clinical diseases in individuals presenting with babesiosis-like symptoms, as well as the infection status of ticks in high risk areas.

Background: Crimean-Congo haemorrhagic fever (CCHF) is a potentially fatal disease endemic in Pakistan. The causative virus is transmitted by the bite of Hyalomma ticks or by contact with infected blood or tissue. First cases of the disease were reported in Pakistan in 1976 but regular outbreaks have been observed since the year 2000. A huge agricultural base with more than 175 million livestock, the concomitant presence of Hyalomma ticks and a lack of precautionary measures to prevent transmission lead to a considerable risk for exposed populations to contract CCHF in Pakistan. At the same time, secondary cases contracted by nosocomial transmission are reported from hospitals., Case Presentation: Here we present an outbreak of CCHF with four of six patients succumbing to the disease before the suspicion for CCHF was raised. Importantly, the main clinical features of these cases were gastrointestinal symptoms without any clinical signs of bleeding. Only the last two patients in this outbreak presented with typical signs of bleeding disorder and were then confirmed being infected by CCHF. Confirmation of diagnosis was done at the National Institute of Health by real-time RT-PCR., Conclusions: This case series highlights the importance of early clinical suspicion for CCHF in exposed individuals and the need for improved precautionary measures against the spread of CCHF within the Pakistani population and hospitals.

Background: Human babesiosis is a worldwide disease caused by intraerythrocytic protozoa of the genus Babesia. It is transmitted by bites from ixodid ticks, and mechanically transmitted by blood transfusion. It is primarily treated with quinine and/or atovaquone, which are not readily available in China. In this study, we developed a novel treatment regimen involving doxycycline monotherapy in a patient with severe Babesia venatorum infection as an alternative therapeutic medication. The aim of our study is to provide a guidance for clinical practice treatment of human babesiosis. Case presentation: A 73-year-old man who had undergone splenectomy and blood transfusion 8 years prior, presented with an unexplained fever, headache, and thrombocytopenia, and was admitted to the Fifth Medical Center of the PLA General Hospital. He was diagnosed with B. venatorum infection by morphological review of thin peripheral blood smears, which was confirmed by multi-gene polymerase chain reaction (PCR), and sequencing of the entire 18s rRNA and partial β-tubulin encoding genes, as well as isolation by animal inoculation. The doxycycline monotherapy regimen (peros, 0.1 g bisindie) was administered following pharmacological guidance and an effective outcome was observed. The patient recovered rapidly following the doxycycline monotherapy. The protozoan load in peripheral blood samples decreased by 88% in hematocrit counts after 8 days, and negative PCR results were obtained after 90 days of follow-up at the hospital. The treatment lasted for 3 months without any side effects or sequelae. The nine-month follow-up survey of the patient did not reveal any signs of recrudescence or anti-babesial tolerance. Conclusions: We have reported a clinical case of successful doxycycline monotherapy for human babesiosis caused by B. venatorum, which provides an optional medical intervention for human babesiosis. [ABSTRACT FROM AUTHOR]

Background: A wide variety of pathogens could be maintained and transmitted by Haemaphysalis longicornis. The aim of this study is to systematically examine the variety of pathogens carried by Haemaphysalis longicornis, an importnatn vector, in tick-borne diseases epidemic area, and to estimate the risk of human infection imposed by tick bites. Methods: Adult questing ticks were collected in Xinyang, central China. Genomic DNA and RNA were extracted from 144 H. longicornis ticks individually, and sequenced respectively as the templates for high-throughput sequencing. Clean reads were compared against the database of NCBI nucleotide collection and specific PCR was performed to confirm the presence of pathogen. Phylogenetic analysis was performed to explore the evolutionary status of pathogens. Results: The assignment of reads to taxa based on BLASTN results revealed the existence of several potential pathogens, including Anaplasma spp., Rickettsia spp., Babesia sp., as well as severe fever with thrombocytopenia syndrome bunyavirus (SFTSV). Comfirmantory PCR assays revealed the existence of Anaplasma bovis (13/144, 9.03%), Anaplasma centrale (2/144, 1.39%), Rickettsia heilongjiangensis (3/144, 2.08%), Rickettsia sp. LON-13 (1/144, 0.69%), Rickettsia raoultii (5/144, 3.47%), Babesia sp. (1/144, 0.69%). SFTSV accounted for the highest detected pathogen with a positive rate of 18.75% (27/144). Three of the ticks (2.08%) were co-infected with SFTSV and A. bovis. Conclusion: Our study provided a broadened list of microorganism that harbored by H. longicornis. In previously unrecognized endemic regions, prokaryotic and eukaryotic infection including Anaplasma spp., Rickettsiae spp., and Babesia spp. should be considered, along with the well-known SFTSV for patients with tick bites history. A novel Babesia species was identified in local natural foci, which needs further investigation in the future. [ABSTRACT FROM AUTHOR]

Background: Viral pathogens belonging to the order Bunyavirales pose a continuous background threat to global health, but the fact remains that they are usually neglected and their distribution is still ambiguously known. We aim to map the geographical distribution of Bunyavirales viruses and assess the environmental suitability and transmission risk of major Bunyavirales viruses in China. Methods: We assembled data on all Bunyavirales viruses detected in humans, animals and vectors from multiple sources, to update distribution maps of them across China. In addition, we predicted environmental suitability at the 10 km × 10 km pixel level by applying boosted regression tree models for two important Bunyavirales viruses, including Crimean-Congo hemorrhagic fever virus (CCHFV) and Rift Valley fever virus (RVFV). Based on model-projected risks and air travel volume, the imported risk of RVFV was also estimated from its endemic areas to the cities in China. Results: Here we mapped all 89 species of Bunyavirales viruses in China from January 1951 to June 2021. Nineteen viruses were shown to infect humans, including ten species first reported as human infections. A total of 447,848 cases infected with Bunyavirales viruses were reported, and hantaviruses, Dabie bandavirus and Crimean-Congo hemorrhagic fever virus (CCHFV) had the severest disease burden. Model-predicted maps showed that Xinjiang and southwestern Yunnan had the highest environmental suitability for CCHFV occurrence, mainly related to Hyalomma asiaticum presence, while southern China had the highest environmental suitability for Rift Valley fever virus (RVFV) transmission all year round, mainly driven by livestock density, mean precipitation in the previous month. We further identified three cities including Guangzhou, Beijing and Shanghai, with the highest imported risk of RVFV potentially from Egypt, South Africa, Saudi Arabia and Kenya. Conclusions: A variety of Bunyavirales viruses are widely distributed in China, and the two major neglected Bunyavirales viruses including CCHFV and RVFV, both have the potential for outbreaks in local areas of China. Our study can help to promote the understanding of risk distribution and disease burden of Bunyavirales viruses in China, and the risk maps of CCHFV and RVFV occurrence are crucial to the targeted surveillance and control, especially in seasons and locations at high risk. [ABSTRACT FROM AUTHOR]

Background: There has been a growing interest in camel anaplasmosis due to its recent emergence in this reservoir species and concerns for its zoonotic potential. The epidemiology of anaplasmosis in camels therefore remains poorly understood mostly because camels belong to marginalised poor and often transhumant populations whose interests are largely neglected. Most studies of anaplasmosis in camels have relied on microscopy and serology for diagnosis and only three studies, undertaken in Tunisia, Saudia Arabia and China, have used molecular diagnostics. The present work characterises Anaplasmataceae strains circulating in the Camelus dromedarius reservoir in Morocco using PCR. Methods: Camels (n = 106) were randomly sampled from 6 regions representing different agro-ecological areas in southern Morocco. Whole blood was collected and screened using PCR methods targeting the gene groEL. Anaplasmataceae strains were characterised by sequence analysis of the gene groEL. Results: A total of 39.62% (42/106) camels screened were positive for Anaplasmataceae spp. GenBank BLAST analysis of five positive sequenced samples revealed that all strains were 100% identical to "Candidatus Anaplasma camelii". Phylogenetic investigation and genetic characterisation of the aligned segment (650 bp) of the gene groEL confirmed high similarity with A. platys. Conclusion: This study demonstrates the circulation of a previously unidentified species of the genus Anaplasma in Morocco which is genetically close to the agent causing canine anaplasmosis but whose main reservoir is thought to be Camelus dromedarius. [ABSTRACT FROM AUTHOR]

We look at the link between climate change and vector-borne diseases in low- and middle-income countries in Africa. The large endemicity and escalating threat of diseases such as malaria and arboviral diseases, intensified by climate change, disproportionately affects vulnerable communities globally. We highlight the urgency of prioritizing research and development, advocating for robust scientific inquiry to promote adaptation strategies, and the vital role that the next generation of African research leaders will play in addressing these challenges. Despite significant challenges such as funding shortages within countries, various pan-African-oriented funding bodies such as the African Academy of Sciences, the Africa Research Excellence Fund, the Wellcome Trust, the U.S. National Institutes of Health, and the Bill and Melinda Gates Foundation as well as initiatives such as the African Research Initiative for Scientific Excellence and the Pan-African Mosquito Control Association, have empowered (or are empowering) these researchers by supporting capacity building activities, including continental and global networking, skill development, mentoring, and African-led research. This article underscores the urgency of increased national investment in research, proposing the establishment of research government agencies to drive evidence-based interventions. Collaboration between governments and scientific communities, sustained by pan-African funding bodies, is crucial. Through these efforts, African nations are likely to enhance the resilience and adaptive capacity of their systems and communities by navigating these challenges effectively, fostering scientific excellence and implementing transformative solutions against climate-sensitive vector-borne diseases. [ABSTRACT FROM AUTHOR]

Kyasanur Forest disease (KFD), a tick-borne viral hemorrhagic fever, is endemic in five districts of Karnataka state, India. Recent reports of the spread of disease to neighboring districts of the Western Ghats, namely Chamarajanagar district in Karnataka, Nilgiri district in Tamil Nadu, Wayanad and Malappuram districts in Kerala, and Pali village in Goa are a cause for concern. Besides vaccination of the affected population, establishing an event-based surveillance system for monkey deaths in the national parks, wildlife sanctuaries and reserve forests of the Western Ghats would help detect the disease early and thereby help implement appropriate control measures. [ABSTRACT FROM AUTHOR]

Background: Freshwater snails of the genera Bulinus spp., Biomphalaria spp., and Oncomelania spp. are the main intermediate hosts of human and animal schistosomiasis. Identification of these snails has long been based on morphological and/or genomic criteria, which have their limitations. These limitations include a lack of precision for the morphological tool and cost and time for the DNA-based approach. Recently, Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight (MALDI–TOF) mass spectrometry, a new tool used which is routinely in clinical microbiology, has emerged in the field of malacology for the identification of freshwater snails. This study aimed to evaluate the ability of MALDI–TOF MS to identify Biomphalariapfeifferi and Bulinusforskalii snail populations according to their geographical origin. Methods: This study was conducted on 101 Bi.pfeifferi and 81 Bu.forskalii snails collected in three distinct geographical areas of Senegal (the North-East, South-East and central part of the country), and supplemented with wild and laboratory strains. Specimens which had previously been morphologically described were identified by MALDI–TOF MS [identification log score values (LSV) ≥ 1.7], after an initial blind test using the pre-existing database. After DNA-based identification, new reference spectra of Bi.pfeifferi (n = 10) and Bu.forskalii (n = 5) from the geographical areas were added to the MALDI–TOF spectral database. The final blind test against this updated database was performed to assess identification at the geographic source level. Results: MALDI–TOF MS correctly identified 92.1% of 101 Bi.pfeifferi snails and 98.8% of 81 Bu.forskalii snails. At the final blind test, 88% of 166 specimens were correctly identified according to both their species and sampling site, with LSVs ranging from 1.74 to 2.70. The geographical source was adequately identified in 90.1% of 91 Bi.pfeifferi and 85.3% of 75 Bu.forskalii samples. Conclusions: Our findings demonstrate that MALDI–TOF MS can identify and differentiate snail populations according to geographical origin. It outperforms the current DNA-based approaches in discriminating laboratory from wild strains. This inexpensive high-throughput approach is likely to further revolutionise epidemiological studies in areas which are endemic for schistosomiasis. [ABSTRACT FROM AUTHOR]

Background: Anthrax, a zoonotic disease caused by the spore-forming bacterium Bacillus anthracis, remains a major global public health concern, especially in countries with limited resources. Sierra Leone, a West African country historically plagued by anthrax, has almost been out of report on this disease in recent decades. In this study, we described a large-scale anthrax outbreak affecting both animals and humans and attempted to characterize the pathogen using molecular techniques. Methods: The causative agent of the animal outbreak in Port Loko District, Sierra Leone, between March and May 2022 was identified using the nanopore sequencing technique. A nationwide active surveillance was implemented from May 2022 to June 2023 to monitor the occurrence of anthrax-specific symptoms in humans. Suspected cases were subsequently verified using quantitative polymerase chain reaction. Full-genome sequencing was accomplished by combining long-read and short-read sequencing methods. Subsequent phylogenetic analysis was performed based on the full-chromosome single nucleotide polymorphisms. Results: The outbreak in Port Loko District, Sierra Leone, led to the death of 233 animals between March 26th and May 16th, 2022. We ruled out the initial suspicion of Anaplasma species and successfully identified B. anthracis as the causative agent of the outbreak. As a result of the government's prompt response, out of the 49 suspected human cases identified during the one-year active surveillance, only 6 human cases tested positive, all within the first month after the official declaration of the outbreak. The phylogenetic analysis indicated that the BaSL2022 isolate responsible for the outbreak was positioned in the A.Br.153 clade within the TransEuroAsian group of B. anthracis. Conclusions: We successfully identified a large-scale anthrax outbreak in Sierra Leone. The causative isolate of B. anthracis, BaSL2022, phylogenetically bridged other lineages in A.Br.153 clade and neighboring genetic groups, A.Br.144 and A.Br.148, eventually confirming the spillover of anthrax from West Africa. Given the wide dissemination of B. anthracis spores, it is highly advisable to effectively monitor the potential reoccurrence of anthrax outbreaks and to launch campaigns to improve public awareness regarding anthrax in Sierra Leone. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). SFTSV has been found in humans, ticks and animals, and SFTS has high mortality and increasing prevalence in East Asia. In the study, the samples (heart, liver, lung, kidney, spleen, brain tissue and serum) were collected from 374 domestic animals and 241 wild animals in Pingqiao District and Xinxian County of Xinyang in Henan Province, China. 275 (44.72%, 275/615) animals were positive for anti-SFTSV antibodies, the anti-SFTSV antibodies positive ratios of domestic and wild animals were 43.58% (163/374) and 46.47% (112/241), respectively. There was no significant difference in domestic and wild animals, but significant differences were detected among different species of animals (χ2 = 112.59, P < 0.0001). Among 615 animals, 105 (17.07%, 105/615) animals were positive for SFTSV RNA, and only one SFTSV strain was isolated from heart tissue of a yellow weasel. The phylogenetic analysis shows that the sequence from animals belonged to the same group with viral sequences obtained from humans. The animals maybe play a reservoir host in maintaining the life cycle of SFTSV in nature. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia (SFTS) caused by SFTS virus (SFTSV) was a tick-borne hemorrhagic fever that posed significant threat to human health in Eastern Asia. The study was designed to measure the seroprevalence of SFTSV antibody in healthy population residing in a high endemic region., Methods: A cohort study was performed on healthy residents in Shangcheng County in Xinyang City from April to December in 2018, where the highest SFTS incidence in China was reported. Anti-SFTSV IgG was measured by indirect enzyme-linked immunosorbent assay and neutralizing antibody (NAb) was detected by using PRNT50. The logistic regression models were performed to analyze the variables that were associated with seropositive rates., Results: Totally 886 individuals were recruited. The baseline seroprevalence that was tested before the epidemic season was 11.9% (70/587) for IgG and 6.8% (40/587) for NAb, which was increased to 13.4% (47/350) and 7.7% (27/350) during the epidemic season, and further to 15.8% (80/508) and 9.8% (50/508) post epidemic. The IgG antibody-based seropositivity was significantly related to the patients aged ≥ 70 years old [adjusted odds ratio (OR) = 2.440, 95% confidence interval (CI): 1.334-4.461 compared to the group of < 50 years old, P = 0.004], recent contact with cats (adjusted OR = 2.195, 95% CI: 1.261-3.818, P = 0.005), and working in tea garden (adjusted OR = 1.698, 95% CI: 1.002-2.880, P = 0.049) by applying multivariate logistic regression model. The NAb based seropositivity was similarly related to the patients aged ≥ 70 years old (adjusted OR = 2.691, 95% CI: 1.271-5.695 compared to the group of < 50 years old, P = 0.010), and recent contact with cats (OR = 2.648, 95% CI: 1.419-4.941, P = 0.002). For a cohort of individuals continually sampled with 1-year apart, the anti-SFTSV IgG were maintained at a stable level, while the NAb level reduced., Conclusions: Subclinical infection might not provide adequate immunity to protect reinfection of SFTSV, thus highlighting the ongoing threats of SFTS in endemic regions, which called for an imperative need for vaccine development. Identification of risk factors might help to target high-risk population for public health education and vaccination in the future., (© 2021. The Author(s).)

Background: Clonorchissinensis, one of the most important food-borne zoonotic trematodes, remains prevalent in China. Understanding its infection status in animals is crucial for controlling human clonorchiasis. Here we conducted a systematic review and meta-analysis to focus on the spatio-temporal disparities of C.sinensis infection in animals in China. Methods: Data on C.sinensis prevalence in snails, the second intermediate hosts, or animal reservoirs in China were extracted from electronic databases including PubMed, Embase, Web of Science, Chinese Wanfang database, CNKI, VIP, and China Biomedical Literature database. A random-effects meta-analysis model was utilized to estimate the pooled prevalence in each of the above animal hosts. Subgroup analysis and multivariable meta-regression were performed to explore potential sources of heterogeneity across studies and compare the temporal disparity of infection rates between high and low epidemic areas. Scatter plots were used to depict the biogeographical characteristics of regions reporting C.sinensis infection in animals. Results: The overall pooled prevalence of C.sinensis was 0.9% (95% CI: 0.6–1.2%) in snails, 14.2% (12.7–15.7%) in the second intermediate host, and 14.3% (11.4–17.6%) in animal reservoirs. Prevalence in low epidemic areas (with human prevalence < 1%) decreased from 0.6% (0.2–1.2%) before 1990 to 0.0% (0.0–3.6%) after 2010 in snails (P = 0.0499), from 20.3% (15.6–25.3%) to 8.8% (5.6–12.6%) in the second intermediate hosts (P = 0.0002), and from 18.3% (12.7–24.7%) to 4.7% (1.0–10.4%) in animal reservoirs. However, no similar decrease in prevalence was observed in high epidemic areas (with human prevalence ≥ 1.0%). C.sinensis infections were predominantly reported in areas with altitudes below 2346 m and annual cumulative precipitation above 345 mm and were mostly concentrated in eastern China. Conclusions: There are spatio-temporal disparities in the animal infections of C.sinensis in different areas of China. Animal infections are primarily concentrated in regions with low altitude and high precipitation. The results suggest that implementing One Health-based comprehensive measures targeting both humans and animals, especially in high epidemic areas, is essential for successful eradication of C.sinensis in China. [ABSTRACT FROM AUTHOR]

Background: The transmission and fatal risk of severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease first discovered in China in 2009, still needed further quantification. This research aimed to analyze the SFTS clusters and assess the transmission and mortality risk for SFTS. Methods: Both epidemiological investigation and case reports regarding SFTS clusters in China during 2011–2021 were obtained from the Public Health Emergency Information Management System of the Chinese Center for Disease Control and Prevention Information System. The transmission risk was evaluated by using the secondary attack rate (SAR) and relative risk (RR). Mortality risk factors were analyzed using a logistic regression model. Results: There were 35 SFTS clusters during 2011–2021 involving 118 patients with a fatality rate of 22.0%. The number of clusters annually increased seasonally from April to September. The clusters mainly occurred in Anhui (16 clusters) and Shandong provinces (8 clusters). The SAR through contact with blood or bloody fluids was much higher than that through contact with non-bloody fluids (50.6% vs 3.0%; χ2 = 210.97, P < 0.05), with an RR of 16.61 [95% confidence interval (CI): 10.23–26.97]. There was a statistically significant difference in the SAR between exposure to the blood of a deceased person during burial preparation and exposure to the living patients' blood (66.7% vs 34.5%; χ2 = 6.40, P < 0.05), with an RR of 1.93 (95% CI: 1.11–3.37). The mortality risk factors were a long interval from onset to diagnosis [odds ratio (OR) = 1.385), 95% CI: 1.083–1.772, P = 0.009) and advanced age (OR: 1.095, 95% CI: 1.031–1.163, P = 0.01). Conclusions: The SFTS clusters showed a high mortality rate and resulted in a high SAR. Contact with a bleeding corpse was associated with a higher infection risk, compared with contacting the blood from living patients. It is important to promote early detection and appropriate case management of patients with SFTS, as well as improved handling of their corpses, to prevent further transmission and mortality. [ABSTRACT FROM AUTHOR]

Background: The One Health (OH) concept has been promoted widely around the globe. OH framework is expected to be applied as an integrated approach to support addressing zoonotic diseases as a significant global health issue and to improve the efficiency and effectiveness of zoonosis prevention and control. This review is intended to overview the social impact of the implementation of OH on zoonosis prevention and control. Methods: A scoping review of studies in the past 10 years was performed to overview the integration feature of OH in zoonosis prevention and control and the social impacts of OH. PubMed and Web of Science were searched for studies published in English between January 2011 and June 2021. The included studies were selected based on predefined criteria. Results: Thirty-two studies were included in this review, and most of them adopted qualitative and semi-qualitative methods. More than 50% of the studies focused on zoonosis prevention and control. Most studies were conducted in low- and middle-income countries in Africa and Asia. Applying OH approach in diseases control integrates policymakers, stakeholders, and academics from various backgrounds. The impact of OH on economic is estimated that it may alleviate the burden of diseases and poverty in the long term, even though more financial support might be needed at the initial stage of OH implementation. OH implementation considers social and ecological factors related to zoonosis transmission and provides comprehensive strategies to assess and address related risks in different communities according to regions and customs. Conclusions: Based on reviewed literature, although there seems to be a lack of guidelines for assessing and visualizing the outcomes of OH implementation, which may limit the large-scale adoption of it, evidence on the contributions of implementing OH concepts on zoonosis prevention and control indicates long-term benefits to society, including a better integration of politics, stakeholders and academics to improve their cooperation, a potential to address economic issues caused by zoonosis, and a comprehensive consideration on social determinants of health during zoonosis prevention and control. [ABSTRACT FROM AUTHOR]

Background: Emerging mite-borne pathogens and associated disease burdens in recent decades are raising serious public health concerns, yet their distributions and ecology remain under-investigated. We aim to describe the geographical distributions of blood-sucking mites and mite-borne agents and to assess their ecological niches in China. Methods: We mapped 549 species of blood-sucking mites belonging to 100 genera at the county level and eight mite-associated agents detected from 36 species of blood-sucking mites in China during 1978–2020. Impacts of climatic and environmental factors on the ecology of 21 predominant vector mites and a leading pathogen, Orientia tsutsugamushi, were assessed using boosted regression tree (BRT) models, and model-predicted risks were mapped. We also estimated the model-predicted number, area and population size of affected counties for each of the 21 mite species in China. Results: Laelaps echidninus is the leading mite species that potentially affects 744 million people, followed by La. jettmari (517 million) and Eulaelaps stabularis (452 million). Leptotrombidium scutellare is the mite species harboring the highest variety of mite-borne agents including four Rickettsia species and two viruses, followed by Eu. stabularis (2 agents), L. palpale (2) and La. echidninus (2). The top two agents that parasitize the largest number of mite species are O. tsutsugamushi (28 species) and hantavirus (8). Mammalian richness, annual mean temperature and precipitation of the driest quarter jointly determine the ecology of the mites, forming four clusters of major mite species with distinct geographic distributions. High-risk areas of O. tsutsugamushi are mainly distributed in southern and eastern coastal provinces where 71.5 million people live. Conclusions: Ecological niches of major mite species and mite-borne pathogens are much more extensive than what have been observed, necessitating expansion of current filed surveillance. [ABSTRACT FROM AUTHOR]

Background: African swine fever (ASF) is a fatal hemorrhagic disease in domestic pigs and wild boar caused by African swine fever virus (ASFV). Since ASF has been introduced into Europe and Asia, the major pig-raising areas, posing a huge threat to the pork industry worldwide. Currently, prevention and control of ASF are basically dependent on strict biosecurity measures and stamping-out policy once ASF occurs. Main text: The major risks of ASF spread are insufficient biosecurity measures and human behaviors. Therefore, a safe and effective vaccine seems to be a reasonable demand for the prevention and control of ASF. Due to the efficacy advantage over other types of vaccines, live attenuated vaccines (LAVs), especially virulence-associated genes deleted vaccines, are likely to be put into emergency and conditional use in restricted areas if ASF is out of control in a country with a huge pig population and pork consumption, like China. However, the safety, efficacy, and genetic stability of current candidate ASF LAVs require comprehensive clinical evaluations prior to country-wide field application. Several critical issues need to be addressed to commercialize an ideal ASF LAV, including a stable cell line for manufacturing vaccines, differentiation of infected from vaccinated animals (DIVA), and cross-protection from different genotypes. Conclusion: A safe and effective DIVA vaccine and an accompanying diagnostic assay will facilitate the prevention, control, and eradication of ASF, which is quite challenging in the near future. [ABSTRACT FROM AUTHOR]

Background: There has been a growing interest in camel anaplasmosis due to its recent emergence in this reservoir species and concerns for its zoonotic potential. The epidemiology of anaplasmosis in camels therefore remains poorly understood mostly because camels belong to marginalised poor and often transhumant populations whose interests are largely neglected. Most studies of anaplasmosis in camels have relied on microscopy and serology for diagnosis and only three studies, undertaken in Tunisia, Saudia Arabia and China, have used molecular diagnostics. The present work characterises Anaplasmataceae strains circulating in the Camelus dromedarius reservoir in Morocco using PCR., Methods: Camels (n = 106) were randomly sampled from 6 regions representing different agro-ecological areas in southern Morocco. Whole blood was collected and screened using PCR methods targeting the gene groEL. Anaplasmataceae strains were characterised by sequence analysis of the gene groEL., Results: A total of 39.62% (42/106) camels screened were positive for Anaplasmataceae spp. GenBank BLAST analysis of five positive sequenced samples revealed that all strains were 100% identical to "Candidatus Anaplasma camelii". Phylogenetic investigation and genetic characterisation of the aligned segment (650 bp) of the gene groEL confirmed high similarity with A. platys., Conclusion: This study demonstrates the circulation of a previously unidentified species of the genus Anaplasma in Morocco which is genetically close to the agent causing canine anaplasmosis but whose main reservoir is thought to be Camelus dromedarius., Trial Registration Number: This study is not a clinical trial and therefore a trial registration number does not apply.

Background: Piroplasms are kinds of tick-borne parasitic apicomplexan protozoa, which are detrimental to humans and animals in tropical and subtropical areas around the world. Up until now, there has been a limited amount of reliable information available about the prevalence of piroplasms infections in wild animals in China. Therefore, we have investigated the infections of Babesia and Theileria species in both domestic and wild animals in Xinyang city, Henan province, where tick-borne diseases have recently been reported. This study aims to analyze the distribution patterns of piroplasms infections in animals, and assess their potential threat to humans in Central China., Methods: Blood samples were collected from sheep, dogs and hedgehogs in two regions, including Shihe District and Luoshan County, of Xinyang city, Henan province from August to December 2012. Babesia spp. and Theileria spp. were detected by polymerase chain reaction (PCR) and identified by sequencing and phylogenetic analysis. Moreover, the characteristics of detected piroplasms in different animal hosts were compared between the two study regions., Results: A total of 227 blood samples were collected from 73 sheep, two dogs and 152 hedgehogs. Babesia spp. was only detected in the two dogs. Theileria spp. was detected both in the sheep and the hedgehogs, and the total positive rate of Theileria spp. in the sheep and the hedgehogs was 57.53% and 13.82%, respectively. Sequencing and phylogenetic analysis revealed that the Theileria spp. detected in the sheep and the hedgehogs were very close to T. lunwenshuni cloned from a small ruminant and Theileria spp. isolated from a febrile hospitalized patient in China., Conclusion: Babesia and Theileria infections were detected in both domestic and wild animals in Xinyang city, Henan province in Central China, thus warranting further studies in these regions.

Background: African swine fever (ASF), caused by African swine fever virus, is a hemorrhagic and often fatal disease of domestic pigs and wild boar, which is notifiable to the World Organization for Animal Health. On August 3, 2018, China reported the first outbreak of ASF in Shenyang, a northeastern city of China. As of October 8, a total of 33 ASF outbreaks were reported in eight provinces in China, the biggest pork producer and consumer in the world. Main body: This commentary summarizes the current situation of ASF in China, measures that China has taken to control the disease, lessons learnt from other countries, challenges and recommendations on ASF control in China, and possible international collaborations on ASF. Conclusions: ASF is an unprecedented disaster and challenge to the Chinese swine industry. It will be a formidable and protracted campaign to control ASF in China, which requires joint participation and coordination of stakeholders and agencies at different levels. [ABSTRACT FROM AUTHOR]

Background: Diseases transmitted to humans by vectors account for 17% of all infectious diseases and remain significant public health problems. Through the years, great strides have been taken towards combatting vectorborne diseases (VBDs), most notably through large scale and coordinated control programmes, which have contributed to the decline of the global mortality attributed to VBDs. However, with environmental changes, including climate change, the impact on VBDs is anticipated to be significant, in terms of VBD-related hazards, vulnerabilities and exposure. While there is growing awareness on the vulnerability of the African continent to VBDs in the context of climate change, there is still a paucity of research being undertaken in this area, and impeding the formulation of evidence-based health policy change. Main body: One way in which the gap in knowledge and evidence can be filled is for donor institutions to support research in this area. The collaboration between the WHO Special Programme for Research and Training in Tropical Diseases (TDR) and the International Centre for Research and Development (IDRC) builds on more than 10 years of partnership in research capacity-building in the field of tropical diseases. From this partnership was born yet another research initiative on VBDs and the impact of climate change in the Sahel and sub-Saharan Africa. This paper lists the projects supported under this research initiative and provides a brief on some of the policy and good practice recommendations emerging from the ongoing implementation of the research projects. Conclusion: Data generated from the research initiative are expected to be uptaken by stakeholders (including communities, policy makers, public health practitioners and other relevant partners) to contribute to a better understanding of the impacts of social, environmental and climate change on VBDs(i.e. the nature of the hazard, vulnerabilities, exposure), and improve the ability of African countries to adapt to and reduce the effects of these changes in ways that benefit their most vulnerable populations. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a newly identified emerging infectious disease, which is caused by a novel bunyavirus (termed SFTSV) in Asia. Although mosquitoes have not been identified as the primary vectors, as revealed by epidemiological surveys, their role in transmitting this SFTSV as a suspicious vector has not been validated. Findings: In this study, we conducted experimental infections of mosquitoes with SFTSV to examine the role of mosquitoes in the transmission of the virus. We did not detect viral replication in Culex pipiens pallens, Aedes aegyptis and Anopheles sinensis as revealed by qRT-PCR assay. In addition, we failed to isolate SFTSV from the Vero cells cultured with suspensions of SFTSV-infected mosquitoes. Conclusion: The results of the present study demonstrate little possibility that mosquitoes act as vectors for the emerging pathogen SFTSV. [ABSTRACT FROM AUTHOR]

Background: Uganda has suffered from a series of epidemics of Human African Trypanosomiasis (HAT), a tsetse transmitted disease, also known as sleeping sickness. The area affected by acute Trypanosoma brucei rhodesiense HAT (rHAT) has been expanding, driven by importation of infected cattle into regions previously free of the disease. These regions are also affected by African Animal Trypanosomiasis (AAT) demanding a strategy for integrated disease control. Methods: In 2008, the Public Private Partnership, Stamp Out Sleeping Sickness (SOS) administered a single dose of trypanocide to 31 486 head of cattle in 29 parishes in Dokolo and Kaberamaido districts. This study examines the impact of this intervention on the prevalence of rHAT and AAT trypanosomes in cattle from villages that had (HAT+ve) or had not (HAT-ve) experienced a recent case of rHAT. Cattle herds from 20 villages were sampled and screened by PCR, pre-intervention and 6-months post-intervention, for the presence or absence of: Trypanosoma brucei s.l.; human infective T. b. rhodesiense; Trypanosoma vivax; and Trypanosoma congolense savannah. Results: Post-intervention, there was a significant decrease in the prevalence of T. brucei s.l. and the human infective sub-species T. b. rhodesiense in village cattle across all 20 villages. The prevalence of T. b. rhodesiense was reduced from 2.4% to 0.74% (P < 0.0001), with the intervention showing greater impact in HAT-ve villages. The number of villages containing cattle harbouring human infective parasites decreased from 15/20 to 8/20, with T. b. rhodesiense infection mainly persisting within cattle in HAT+ve villages (six/eight). The proportion of T. brucei s.l. infections identified as human infective T. b. rhodesiense decreased after the intervention from 8.3% (95% CI= 11.1-5.9%) to 4.1% (95% CI = 6. 8-2.3%). Villages that had experienced a recent human case (HAT+ve villages) showed a significantly higher prevalence for AAT both pre- and post-intervention. For AAT the prevalence of T. vivax was significantly reduced from 5.9% to 0. 05% post-intervention while the prevalence of T. congolense increased from 8.0% to 12.2%. Conclusions: The intervention resulted in a significant decrease in the prevalence of T. brucei s.l., human infective T. b. rhodesiense and T. vivax infection in village cattle herds. The proportion of T. brucei s.l. that were human infective, decreased from 1:12 T. brucei s.l. infections before the intervention to 1:33 post-intervention. It is clearly more difficult to eliminate T. b. rhodesiense from cattle in villages that have experienced a human case. Evidence of elevated levels of AAT in livestock within village herds is a useful indicator of risk for rHAT in Uganda. Integrated veterinary and medical surveillance is key to successful control of zoonotic rHAT. [ABSTRACT FROM AUTHOR]

This paper highlights the critical importance of evidence on vector-borne diseases (VBD) prevention and control interventions in urban settings when assessing current and future needs, with a view to setting policy priorities that promote inclusive and equitable urban health services. Research should produce knowledge about policies and interventions that are intended to control and prevent VBDs at the population level and to reduce inequities. Such interventions include policy, program, and resource distribution approaches that address the social determinants of health and exert influence at organizational and system levels. [ABSTRACT FROM AUTHOR]

Mechanisms and outcomes of host-parasite interactions during malaria co-infections with gastrointestinal helminths are reasonably understood. In contrast, very little is known about such mechanisms in cases of malaria co-infections with tissue-dwelling parasites. This is lack of knowledge is exacerbated by misdiagnosis, lack of pathognomonic clinical signs and the chronic nature of tissue-dwelling helminthic infections. A good understanding of the implications of tissuedwelling parasitic co-infections with malaria will contribute towards the improvement of the control and management of such co-infections in endemic areas. This review summarises and discusses current information available and gaps in research on malaria co-infection with gastro-intestinal helminths and tissue-dwelling parasites with emphasis on helminthic infections, in terms of the effects of migrating larval stages and intra and extracellular localisations of protozoan parasites and helminths in organs, tissues, and vascular and lymphatic circulations. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a newly identified emerging infectious disease, which is caused by a novel bunyavirus (termed SFTSV) in Asia. Although mosquitoes have not been identified as the primary vectors, as revealed by epidemiological surveys, their role in transmitting this SFTSV as a suspicious vector has not been validated., Findings: In this study, we conducted experimental infections of mosquitoes with SFTSV to examine the role of mosquitoes in the transmission of the virus. We did not detect viral replication in Culex pipiens pallens, Aedes aegyptis and Anopheles sinensis as revealed by qRT-PCR assay. In addition, we failed to isolate SFTSV from the Vero cells cultured with suspensions of SFTSV-infected mosquitoes., Conclusion: The results of the present study demonstrate little possibility that mosquitoes act as vectors for the emerging pathogen SFTSV.

Background: Infectious diseases encompass a large spectrum of diseases that threaten human health, and coinfection is of particular importance because pathogen species can interact within the host. Currently, the antagonistic relationship between different pathogens during concurrent coinfections is defined as one in which one pathogen either manages to inhibit the invasion, development and reproduction of the other pathogen or biologically modulates the vector density. In this review, we provide an overview of the phenomenon and mechanisms of antagonism of coinfecting pathogens involving parasites. Main body: This review summarizes the antagonistic interaction between parasites and parasites, parasites and viruses, and parasites and bacteria. At present, relatively clear mechanisms explaining polyparasitism include apparent competition, exploitation competition, interference competition, biological control of intermediate hosts or vectors and suppressive effect on transmission. In particular, immunomodulation, including the suppression of dendritic cell (DC) responses, activation of basophils and mononuclear macrophages and adjuvant effects of the complement system, is described in detail. Conclusions: In this review, we summarize antagonistic concurrent infections involving parasites and provide a functional framework for in-depth studies of the underlying mechanisms of coinfection with different microorganisms, which will hasten the development of promising antimicrobial alternatives, such as novel antibacterial vaccines or biological methods of controlling infectious diseases, thus relieving the overwhelming burden of ever-increasing antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Background: Drylands, which are among the biosphere's most naturally limiting and environmentally variable ecosystems, constitute three-quarters of the African continent. As a result, environmental sustainability and human development along with vector-borne disease (VBD) control historically have been especially challenging in Africa, particularly in the sub-Saharan and Sahelian drylands. Here, the VBD burden, food insecurity, environmental degradation, and social vulnerability are particularly severe. Changing climate can exacerbate the legion of environmental health threats in Africa, the social dimensions of which are now part of the international development agenda. Accordingly, the need to better understand the dynamics and complex coupling of populations and environments as exemplified by drylands is increasingly recognized as critical to the design of more sustainable interventions. Main body: This scoping review examines the challenge of vector-borne disease control in drylands with a focus on Africa, and the dramatic, ongoing environmental and social changes taking place. Dryland societies persisted and even flourished in the past despite changing climates, extreme and unpredictable weather, and marginal conditions for agriculture. Yet intrusive forces largely out of the control of traditional dryland societies, along with the negative impacts of globalization, have contributed to the erosion of dryland's cultural and natural resources. This has led to the loss of resilience underlying the adaptive capacity formerly widely exhibited among dryland societies. A growing body of evidence from studies of environmental and natural resource management demonstrates how, in light of dryland system's inherent complexity, these factors and top-down interventions can impede sustainable development and vector-borne disease control. Strengthening adaptive capacity through community-based, participatory methods that build on local knowledge and are tailored to local ecological conditions, hold the best promise of reversing current trends. Conclusions: A significant opportunity exists to simultaneously address the increasing threat of vector-borne diseases and climate change through methods aimed at strengthening adaptive capacity. The integrative framework and methods based on social-ecological systems and resilience theory offers a novel set of tools that allow multiple threats and sources of vulnerability to be addressed in combination. Integration of recent advances in vector borne disease ecology and wider deployment of these tools could help reverse the negative social and environmental trends currently seen in African drylands. [ABSTRACT FROM AUTHOR]

Background: Two health concerns primarily related to triatomine bugs are transmission of Trypanosoma cruzi through infective feces, and allergic reactions induced by triatomine bites. In the Southwestern United States, reduviid bugs bites commonly cause insect allergy. In South China, four cases of anaphylactic shock have been reported after this bite exposure. To further classify the species of these bugs and confirm the sensitization of the triatomine saliva, we caught triatomine bugs from the region where the bites occurred and performed phylogenetic and immunohistochemical (IHC) analysis. Methods: Triatomine bugs were collected in Donghai Island of Zhanjiang City in South China. The genomic DNA was extracted from three legs of the bugs. The fragments of mitochondrial 16S rRNA, cytochrome c oxidase subunit I (COI) gene and nuclear ribosomal 18S and 28S rRNA genes were obtained by PCR and sequenced. A phylogenetic tree was constructed based on the sequence of 16S rRNA gene using a maximum likelihood method with MEGA 7.0 software. Trypanosomal specific fragments and vertebrate COI genes were amplified from the fecal DNA to detect the infection of trypanosomes and analyze the blood feeding patterns, respectively. Paraffin-embedded sections were then prepared from adult triatomines and sent for IHC staining. Results: We collected two adult triatomine bugs in Donghai Island. Morphological and molecular analyses indicated that the triatomines were Triatoma rubrofasciata. No fragments of T. cruzi or other trypanosomes were detected from the fecal DNA. Mitochondrial gene segments of Homo sapiens and Mus musculus were successfully amplified. The allergens which induced specific IgE antibodies in human serum were localized in the triatomine saliva by IHC assay. Conclusions: The two triatomine bugs from Donghai Island were T. rubrofasciata. They had bitten humans and mice. Their saliva should contain the allergens related to the allergic symptoms and even anaphylactic shock of exposed residents. Great consideration should be given to this triatomine bugs due to their considerable distribution and potential threat to public health in South China. [ABSTRACT FROM AUTHOR]

Mechanisms and outcomes of host-parasite interactions during malaria co-infections with gastrointestinal helminths are reasonably understood. In contrast, very little is known about such mechanisms in cases of malaria co-infections with tissue-dwelling parasites. This is lack of knowledge is exacerbated by misdiagnosis, lack of pathognomonic clinical signs and the chronic nature of tissue-dwelling helminthic infections. A good understanding of the implications of tissue-dwelling parasitic co-infections with malaria will contribute towards the improvement of the control and management of such co-infections in endemic areas. This review summarises and discusses current information available and gaps in research on malaria co-infection with gastro-intestinal helminths and tissue-dwelling parasites with emphasis on helminthic infections, in terms of the effects of migrating larval stages and intra and extracellular localisations of protozoan parasites and helminths in organs, tissues, and vascular and lymphatic circulations.

Background: Kyasanur Forest disease (KFD) is a febrile illness characterized by hemorrhages, and is reported endemic in the Shimoga district in Karnataka state, India. It is caused by the KFD virus (KFDV) of the family Flaviviridae, and is transmitted to monkeys and humans by Haemaphysalis ticks., Findings: We investigated a new focus of KFD among tribals in a reserve forest in Kerala state, India. A suspected case was defined as a person presenting with acute fever, headache, or myalgia. Human sera were collected and tested for KFDV RNA by real-time RT-PCR, RT-nPCR assay, and anti-KFDV IgM and IgG by ELISA. The index case was a tribal woman with febrile illness, severe myalgia, gum bleeding, and hematemesis. Anti-KFDV IgM antibody was detected in acute and convalescent sera of the index case along with IgG in the second serum. None of her family members reported fever. On verbal autopsy, two more fatal cases were identified as probable primary cases. Acute serum from a case in the second cluster was detected positive for KFDV RNA by real time RT-PCR (Ct = 32) and RT-nPCR. Sequences of E gene showed highest similarity of 98.0% with the KFDV W-377 isolate nucleotide and 100% identity with amino acid. Anti-KFDV IgM was detected in the serum of one family member of the index case, as well as in one out of 17 other tribals., Conclusions: We confirmed a new focus of KFDV activity among tribals in a reserve forest in the Malappuram district of Kerala, India.

Background: The emergence and re-emergence of vector-borne and other infectious diseases of poverty pose a threat to the health of populations living in urban and low-income settings. A detailed understanding of intervention strategies, including effectiveness of past outbreak containment, is necessary to improve future practices. The objective was to determine what is known about the effectiveness of containment measures for emerging and re-emerging vector-borne and other infectious diseases of poverty in urban settings and identify research gaps and implications for public health practice. Main body: We conducted a scoping review and systematically searched peer-reviewed and grey literature published between 2000 and 2016. Different data extraction tools were used for data coding and extraction, and data on implementation process and transferability were extracted from all studies. A quality assessment was conducted for each included study. We screened 205 full-text articles and reports for a total of 31 articles included in the review. The quality of the studies was generally low to moderate. The largest body of evidence concerned control activities for Ebola virus and dengue fever. The majority of interventions (87%) relied on multiple types of measures, which were grouped into four categories: 1) healthcare provision; 2) epidemiological investigation and/or surveillance; 3) environmental or sanitary interventions; and 4) community-based interventions. The quality of the majority of studies (90%) was poor or moderate, and one-third of the studies did not provide a clear description of the outcomes and of the procedures and/or tools used for the intervention. Conclusions: Our results highlight the difficulty of establishing causation when assessing the effect of containment measures. Studies that extend beyond solely reporting on effectiveness and take into account the complexity of real-world settings are urgently needed. We recommend the allocation of research efforts to the evaluation of the implementation processes of interventions as well as their comprehensive and systematic description using validated checklists. [ABSTRACT FROM AUTHOR]

Background: Over half the world’s human populations are currently at risk from vector-borne diseases (VBDs), and the heaviest burden is borne by the world’s poorest people, communities, and countries. The aim of this study was to conduct a review on VBD interventions relevant to housing and hygiene (including sanitation and waste management) in urban areas. Main body: We conducted a scoping review, which involved systematically searching peer-reviewed and grey literature published between 2000 and 2016 using five scientific databases and one database for grey literature. Different data extraction tools were used for data coding and extraction. We assessed the quality of each study using the Mixed Methods Appraisal Tool and extracted descriptive characteristics and data about implementation process and transferability from all studies using the Template for Intervention Description and Replication and ASTAIRE (a tool for analyzing the transferability of health promotion interventions) tools. We reviewed 44 studies. Overall, the studies were judged to be of high risk for bias. Our results suggest multifaceted interventions, particularly community-based interventions, have the potential to achieve wider and more sustained effects than do standard vertical single-component programs. The evaluations of multifaceted interventions tend to include integrated evaluations, using not only entomological indicators but also acceptability and sustainability indicators. Conclusions: This review highlighted the important need for higher quality research in VBDs and improved and standardized reporting of interventions. Significant research gaps were found regarding qualitative research and implementation research, and results highlighted the need for more interventions focus on sanitation and hygiene practices. [ABSTRACT FROM AUTHOR]

Background: Transmission dynamics, vectorial capacity, and co-infections have substantial impacts on vector-borne diseases (VBDs) affecting urban and suburban populations. Reviewing key factors can provide insight into priority research areas and offer suggestions for potential interventions. Main body: Through a scoping review, we identify knowledge gaps on transmission dynamics, vectorial capacity, and co-infections regarding VBDs in urban areas. Peer-reviewed and grey literature published between 2000 and 2016 was searched. We screened abstracts and full texts to select studies. Using an extraction grid, we retrieved general data, results, lessons learned and recommendations, future research avenues, and practice implications. We classified studies by VBD and country/continent and identified relevant knowledge gaps. Of 773 articles selected for full-text screening, 50 were included in the review: 23 based on research in the Americas, 15 in Asia, 10 in Africa, and one each in Europe and Australia. The largest body of evidence concerning VBD epidemiology in urban areas concerned dengue and malaria. Other arboviruses covered included chikungunya and West Nile virus, other parasitic diseases such as leishmaniasis and trypanosomiasis, and bacterial rickettsiosis and plague. Most articles retrieved in our review combined transmission dynamics and vectorial capacity; only two combined transmission dynamics and co-infection. The review identified significant knowledge gaps on the role of asymptomatic individuals, the effects of co-infection and other host factors, and the impacts of climatic, environmental, and socioeconomic factors on VBD transmission in urban areas. Limitations included the trade-off from narrowing the search strategy (missing out on classical modelling studies), a lack of studies on co-infections, most studies being only descriptive, and few offering concrete public health recommendations. More research is needed on transmission risk in homes and workplaces, given increasingly dynamic and mobile populations. The lack of studies on co-infection hampers monitoring of infections transmitted by the same vector. Conclusions: Strengthening VBD surveillance and control, particularly in asymptomatic cases and mobile populations, as well as using early warning tools to predict increasing transmission, were key strategies identified for public health policy and practice. [ABSTRACT FROM AUTHOR]

Background: Climate-based disease forecasting has been proposed as a potential tool in climate change adaptation for the health sector. Here we explore the relevance of climate data, drivers and predictions for vector-borne disease control efforts in Africa. Methods: Using data from a number of sources we explore rainfall and temperature across the African continent, from seasonality to variability at annual, multi-decadal and timescales consistent with climate change. We give particular attention to three regions defined as WHO-TDR study zones in Western, Eastern and Southern Africa. Our analyses include 1) time scale decomposition to establish the relative importance of year-to-year, decadal and long term trends in rainfall and temperature; 2) the impact of the El Niño Southern Oscillation (ENSO) on rainfall and temperature at the Pan African scale; 3) the impact of ENSO on the climate of Tanzania using high resolution climate products and 4) the potential predictability of the climate in different regions and seasons using Generalized Relative Operating Characteristics. We use these analyses to review the relevance of climate forecasts for applications in vector borne disease control across the continent. Results: Timescale decomposition revealed long term warming in all three regions of Africa – at the level of 0.1–0.3 °C per decade. Decadal variations in rainfall were apparent in all regions and particularly pronounced in the Sahel and during the East African long rains (March–May). Year-to-year variability in both rainfall and temperature, in part associated with ENSO, were the dominant signal for climate variations on any timescale. Observed climate data and seasonal climate forecasts were identified as the most relevant sources of climate information for use in early warning systems for vector-borne diseases but the latter varied in skill by region and season. Conclusions: Adaptation to the vector-borne disease risks of climate variability and change is a priority for government and civil society in African countries. Understanding rainfall and temperature variations and trends at multiple timescales and their potential predictability is a necessary first step in the incorporation of relevant climate information into vector-borne disease control decision-making. [ABSTRACT FROM AUTHOR]

Background: With increases in global travel and trade, the spread of arboviruses is undoubtedly alarming. Pathogen detection in field-caught mosquitoes can provide the earliest possible warning of transmission. Insect-specific flavivirus (ISFV) has been first detected in 1991 and documented worldwide in the latest ten years. Although infection with ISFVs is apparently limited to insects, an increase in the infection rate of mosquito-borne flaviviruses may be able to induce cytopathic effects in vertebrate cells during co-infection with other human pathogens. However, little is known whether ISFVs persist in most regions of China. Methods: During the mosquito activity season in 2016, a surveillance program was carried out to detect ISFVs in mosquitoes in metropolitan Shanghai, China. The presence of ISFVs was randomly tested in different species of mosquitoes using RT-PCR-based and hemi-nested PCR assays, following by the sequencing of PCR products. Sequences from positive pooled samples were compared with those deposited in GenBank. Thereafter, sequences of representative insect flaviviruses were used for further phylogenetic and molecular evolutionary analyses. Results: Our investigations showed: (1) the presence of Aedes flavivirus (AEFV) in 11/161 pooled samples (nine pools in Songjiang District, one pool in Huangpu District, and one pool in Qingpu District) of Aedes albopictus , (2) the presence of Quang Binh virus (QBV) in 10/195 pooled samples (all in Chongming District) of Culex tritaeniorhynchus ; and (3) the presence of Culex flavivirus (CxFV) in 9/228 pooled samples (six pools in Pudong New Area, two pools in Huangpu District, and one pool in Chongming District) of Cx. pipiens. Furthermore, phylogenetic analyses of the gene sequences of envelope proteins indicated that Shanghai CxFV strains belonged to the Asia/USA genotype. The overall maximum likelihood estimation values (and 95% confidence interval) for CxFV, QBV, and AEFV in mosquitoes collected in Shanghai in 2016 were 1.34 (0.66–2.45), 1.65 (0.87–2.85), and 1.51 (0.77–2.70) per 1000, respectively. Conclusions: This study reveals the presence and the geographical distribution of ISFVs, and determines the genetic variation and the infection rate of ISFVs in Shanghai, China. At least, three insect flaviviruses including ISFVs, AEFV, CxFV, and QBV, co-circulate in this area. To our knowledge, this is the first report of AEFV in China. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) have become useful tools to extend human abilities and capacities. Currently UAVs are being used for the surveillance of environmental factors related to the transmission of infectious diseases. They have also been used for delivering therapeutic drugs and life-saving supplies to patients or isolated persons in extreme conditions. There have been very few applications of UAVs for disease surveillance, control and prevention to date. However, we foresee many uses for these machines in the fight against zoonotic disease. The control of zoonoses has been a big challenge as these diseases are naturally maintained in animal populations. Among 868 reported zoonoses, echinococcosis (hydatid disease) is one of the most severe public health problems and listed as one of 17 neglected tropical diseases targeted for control by the World Health Organization. Infected dogs (domestic or stray) play the most important role as definitive hosts in maintaining the transmission of echinococcosis. However, the actual contribution of wild canines to transmission has received little attention as yet, but should certainly not be ignored. This paper summarizes the history of development and application of UAVs, with an emphasis on their potential use for zoonosis control. As an example, we outline a pilot trial of echinococcosis control in the Qinghai-Tibet Plateau region, in which UAVs were used to deliver baits with praziquantel for wildlife deworming. The data suggested that this is a cost-effective and efficient approach to the control of zoonotic diseases transmitted among wild animal populations. [ABSTRACT FROM AUTHOR]