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A combination of accelerated population growth and severe droughts has created pressure on food security and driven the development of irrigation schemes across sub-Saharan Africa. Irrigation has been associated with increased malaria risk, but risk prediction remains difficult due to the heterogeneity of irrigation and the environment. While investigating transmission dynamics is helpful, malaria models cannot be applied directly in irrigated regions as they typically rely only on rainfall as a source of water to quantify larval habitats. By coupling a hydrologic model with an agent-based malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of an existing irrigation scheme on malaria transmission dynamics. The inclusion of hydrologic processes increased the variability of larval habitat area by around two-fold and resulted in reduction in malaria transmission by 60%. In addition, irrigation increased all habitat types in the dry season by up to 7.4 times. It converted temporary and semi-permanent habitats to permanent habitats during the rainy season, which grew by about 24%. Consequently, malaria transmission was sustained all-year round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we evaluated the spatiotemporal distribution of adult vectors under the effect of irrigation by resolving habitat heterogeneity. These findings could help larval source management by identifying transmission hotspots and prioritizing resources for malaria elimination planning.

Abstract Lymphatic filariasis (LF) is a crippling and disfiguring parasitic condition. India accounts for 55% of the world’s LF burden. The filarial parasite Wuchereria bancrofti is known to cause 99.4% of the cases while, Brugia malayi accounts for 0.6% of the issue occurring mainly in some pockets of Odisha and Kerala states. The Balasore (Baleswar) district of Odisha has been a known focus of B. malayi transmission. We employed molecular xenomonitoring to detect filarial parasite DNA in vectors. In six selected villages, Gravid traps were used to collect Culex mosquitoes and hand catch method using aspirators was followed for collection of mansonioides. A total of 2903 mosquitoes comprising of Cx. quinquefasciatus (n = 2611; 89.94%), Cx. tritaeniorhynchus (n = 100; 3.44%), Mansonia annuliferea (n = 139; 4.78%) and Mansonia uniformis (n = 53; 1.82%) were collected from six endemic villages. The species wise mosquitoes were made into 118 pools, each with a maximum of 25 mosquitoes, dried and transported to the laboratory at VCRC, Puducherry. The mosquito pools were subjected to parasite DNA extraction, followed by Real-time PCR using LDR and HhaI probes to detect W. bancrofti and B. malayi infections, respectively. Seven pools (6.66%) of Cx. quinquefasciatus, showed infection with only W. bancrofti while none of the pools of other mosquito species showed infection with either W. bancrofti or B. malayi. Although the study area is endemic to B. malayi, none of the vectors of B. malayi was found with parasite infection. This study highlights the ongoing transmission of bancroftian filariasis in the study villages of Balasore district of Odisha and its implications for evaluating LF elimination programme.

Lymphatic filariasis (LF) is a crippling and disfiguring parasitic condition. India accounts for 55% of the world's LF burden. The filarial parasite Wuchereria bancrofti is known to cause 99.4% of the cases while, Brugia malayi accounts for 0.6% of the issue occurring mainly in some pockets of Odisha and Kerala states. The Balasore (Baleswar) district of Odisha has been a known focus of B. malayi transmission. We employed molecular xenomonitoring to detect filarial parasite DNA in vectors. In six selected villages, Gravid traps were used to collect Culex mosquitoes and hand catch method using aspirators was followed for collection of mansonioides. A total of 2903 mosquitoes comprising of Cx. quinquefasciatus (n = 2611; 89.94%), Cx. tritaeniorhynchus (n = 100; 3.44%), Mansonia annuliferea (n = 139; 4.78%) and Mansonia uniformis (n = 53; 1.82%) were collected from six endemic villages. The species wise mosquitoes were made into 118 pools, each with a maximum of 25 mosquitoes, dried and transported to the laboratory at VCRC, Puducherry. The mosquito pools were subjected to parasite DNA extraction, followed by Real-time PCR using LDR and HhaI probes to detect W. bancrofti and B. malayi infections, respectively. Seven pools (6.66%) of Cx. quinquefasciatus, showed infection with only W. bancrofti while none of the pools of other mosquito species showed infection with either W. bancrofti or B. malayi. Although the study area is endemic to B. malayi, none of the vectors of B. malayi was found with parasite infection. This study highlights the ongoing transmission of bancroftian filariasis in the study villages of Balasore district of Odisha and its implications for evaluating LF elimination programme. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that bioclimatic conditions affect the species richness, abundance, and diversity of sand flies in neighboring physiographic regions with endemic transmission of cutaneous leishmaniasis. A sampling program was performed in southeastern Mexico in the High Plateau of Chiapas and the Eastern Mountains physiographic regions, between April 2009 and March 2011. CDC light traps were placed in five randomly selected houses, four CDC traps in four transects in the surrounding vegetation zones, and a modified Magoon trap baited with one protected person was installed at the periphery of the villages at each study site. A total of 12,349 sand flies were identified as species, of which 98.2% were collected in the Eastern Mountains and the rest in the High Plateau of Chiapas. The Eastern Mountains region recorded a significantly higher diversity (H' = 2.04), with a species richness of 27 sand flies species and a higher evenness index (J´ = 0.62) compared to the High Plateau of Chiapas region (H' = 1.02, S = 10, J´ = 0.31). Psychodopygus panamensis (Shannon) (Diptera: Psychodidae) and Pintomyia (Pifanomyia) ovallesi (Ortiz) were the most abundant species in the Eastern Mountains, whereas Lutzomyia (Tricholateralis) cruciata (Coquillett) was most abundant in the High Plateau of Chiapas. We conclude that the differences in species richness, diversity, and abundance of sand flies between these two physiographic regions are due to the bioclimatic effects that in the Eastern Mountains are favorable for the formation of microhabitats due to the warm-warm conditions and the humid-temperate conditions which act as limiting factors in the High Plateau of Chiapas region. In addition, changes in land use due to anthropogenic activities significantly affected the structure of sand fly communities in both regions. [ABSTRACT FROM AUTHOR]

A combination of accelerated population growth and severe droughts has created pressure on food security and driven the development of irrigation schemes across sub‐Saharan Africa. Irrigation has been associated with increased malaria risk, but risk prediction remains difficult due to the heterogeneity of irrigation and the environment. While investigating transmission dynamics is helpful, malaria models cannot be applied directly in irrigated regions as they typically rely only on rainfall as a source of water to quantify larval habitats. By coupling a hydrologic model with an agent‐based malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of an existing irrigation scheme on malaria transmission dynamics. The inclusion of hydrologic processes increased the variability of larval habitat area by around two‐fold and resulted in reduction in malaria transmission by 60%. In addition, irrigation increased all habitat types in the dry season by up to 7.4 times. It converted temporary and semi‐permanent habitats to permanent habitats during the rainy season, which grew by about 24%. Consequently, malaria transmission was sustained all‐year round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we evaluated the spatiotemporal distribution of adult vectors under the effect of irrigation by resolving habitat heterogeneity. These findings could help larval source management by identifying transmission hotspots and prioritizing resources for malaria elimination planning. Plain Language Summary: Population growth and severe droughts have driven the development of irrigation schemes across sub‐Saharan Africa, which can increase malaria risk. Risk prediction remains difficult due to the heterogeneity of irrigation and the environment. Malaria models are seldom used to investigate the effect of irrigation as they typically rely only on rainfall to quantify larval habitats. By coupling a hydrologic model with a malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of the local irrigation on malaria transmission. The inclusion of hydrologic processes increased the variability of larval habitat area and resulted in a significant reduction in malaria transmission. In addition, irrigation increased all habitat types in the dry season and prolonged habitat stability during the rainy season. Consequently, malaria transmission was sustained year‐round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we demonstrated how irrigation could affect the spatiotemporal distribution of larval habitats and adult mosquitoes. These findings could help identify mosquito breeding hotspots and prioritize resources for malaria elimination planning. Key Points: An agent‐based malaria model was coupled with a hydrologic model to spatially simulate transmission by resolving habitat heterogeneityThe coupling framework enhanced larval habitat area variability which resulted in a lower malaria transmission predictionIrrigation sustained transmission year‐round, intensifying and shifting the peak forward by 1 month from the original period [ABSTRACT FROM AUTHOR]

Abstract A combination of accelerated population growth and severe droughts has created pressure on food security and driven the development of irrigation schemes across sub‐Saharan Africa. Irrigation has been associated with increased malaria risk, but risk prediction remains difficult due to the heterogeneity of irrigation and the environment. While investigating transmission dynamics is helpful, malaria models cannot be applied directly in irrigated regions as they typically rely only on rainfall as a source of water to quantify larval habitats. By coupling a hydrologic model with an agent‐based malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of an existing irrigation scheme on malaria transmission dynamics. The inclusion of hydrologic processes increased the variability of larval habitat area by around two‐fold and resulted in reduction in malaria transmission by 60%. In addition, irrigation increased all habitat types in the dry season by up to 7.4 times. It converted temporary and semi‐permanent habitats to permanent habitats during the rainy season, which grew by about 24%. Consequently, malaria transmission was sustained all‐year round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we evaluated the spatiotemporal distribution of adult vectors under the effect of irrigation by resolving habitat heterogeneity. These findings could help larval source management by identifying transmission hotspots and prioritizing resources for malaria elimination planning.

Operationalizing global One Health strategies at the field level to prevent and control vector-borne and zoonotic diseases (VBZDs) is of significant public health importance. Such strategies should be coordinated at the human–animal–ecosystems interface and applied at the national, regional, and global levels through the enforcement of effective policies. We aimed to develop a regional framework that can aid countries of the World Health Organization Eastern Mediterranean region to better prevent, detect, and respond to VBZDs events. This strategic guidance is a twelve-element framework drafted using various guidance documents and peer-reviewed scientific literatures, incorporating recommendations made through expert consultations. The framework elements were then integrated within a logical framework designed for practical implementation of One Health at regional and country level.

Vector-borne infectious diseases cause more than 700,000 deaths a year and represent an increasing threat to public health worldwide. Strategies to mitigate the spread of vector-borne diseases can benefit from a thorough understanding of all mechanisms that contribute to viral propagation in human. A recent study showed that Aedes mosquitoes (the vectors for dengue and Zika virus, among others) are preferentially attracted to infected hosts. In order to determine the impact of this factor on viral spread, we built a dedicated agent-based model and parameterized it on dengue fever. We then performed a systematic study of how mosquitoes' preferential attraction for infected hosts affects viral load and persistence of the infection. Our results indicate that even small values of preferential attraction have a dramatic effect on the number of infected individuals and the persistence of the infection in the population. Taken together, our results suggests that interventions aimed at decreasing the preferential attraction of vectors for infected hosts can reduce viral transmission and thus can have public health implications.

Canine visceral leishmaniasis has been denoted as neglected despite being a very well-known disease. Trace element alteration has been recognized in humans with visceral and cutaneous leishmaniasis, together with canine visceral leishmaniasis. The trace elements occupy a vital position in the immunological system, and host immune responses mitigate defense against leishmaniasis. We aimed to select trace elements in a total of 45 dogs of several breeds; those at the age of 11 months to 6 and from both sexes (26 male and 19 female) were enrolled in the study. The dogs included in the study were divided into leishmaniasis-infected and noninfected groups. All cases in this study were included according to written owner consent. The trace element analysis of serum samples was carried out by using an inductively coupled plasma-optical emission spectrometry. The results of our study revealed that between the canine visceral leishmaniasis infected group and the uninfected group, Leishmania-positive dogs had significantly lower levels of Se (p < 0.001) and Zn (p < 0.001) compared to the negative ones. These results should be carefully elucidated in an attempt to analyze immune responses in dogs with canine visceral leishmaniasis. [ABSTRACT FROM AUTHOR]

The survival of life on earth depends on equilibrium between the organisms and the environment. The monsoon is a seasonal variation prevailing in the Indian sub-continent. Monsoon has two seasons which are separated by a transition. The infectious diseases epidemiology is affected by both climatic and societal influences. An interaction of climatic and societal influence favours the infectious disease exposure in a population. The infectious diseases affecting the population can be broadly classified as vector borne diseases, food borne diseases, water borne diseases, and respiratory diseases. The rainfall associated change in temperature and floods favours the survival of infectious diseases and their transmitting vectors. The changing global climatic trends including the EL nino Southern oscillation bring undue rainfall during other seasons. The drastic events associated with these climatic changes affect the heath and sanitation infrastructure. India being a developing country has more vulnerability to such infections. A better strengthening of the infrastructure and health policies is the need of the hour to curb the infections.

There has been a dramatic increase in the frequency of arboviral disease epidemics among humans and domestic animals worldwide in recent decades. Some of these infections have also undergone significant geographical expansion owing to uncontrolled urbanization leading to changes in vector distribution and/or adaptation of the etiologic agent to more anthropophilic vectors. Arboviral infections such as chikungunya have re-emerged in certain parts of the world, such as India (where chikungunya re-emerged in 2006 after 32 years of quiescence). Existing surveillance systems for arboviral infections in developing countries face several issues, such as being dependent on reporting of loosely defined clinical syndromes and infrequent laboratory confirmation. The recent re-emergence of Zika virus infections and its complications in South America underscore the urgent need for advancements in scientific knowledge on the biology of the arboviral agents and their vectors, innovations concerning diagnostic technologies, vector control measures, and therapeutic approaches. India, a tropical country, harbors an abundance of arthropod vectors capable of hosting and propagating viral infections. These vectors can transmit infections within humans, animals and also across species. This review focuses on viral infections in humans transmitted by arthropod vectors.

Abstract Background Malaria causes 400 thousand deaths worldwide annually. In 2018, 25% (187,693) of the total malaria cases in the Americas were in Brazil, with nearly all (99%) Brazilian cases in the Amazon region. The Bolsa Família Programme (BFP) is a conditional cash transfer (CCT) programme launched in 2003 to reduce poverty and has led to improvements in health outcomes. CCT programmes may reduce the burden of malaria by alleviating poverty and by promoting access to healthcare, however this relationship is underexplored. This study investigated the association between BFP coverage and malaria incidence in Brazil. Methods A longitudinal panel study was conducted of 807 municipalities in the Brazilian Amazon between 2004 and 2015. Negative binomial regression models adjusted for demographic and socioeconomic covariates and time trends were employed with fixed effects specifications. Results A one percentage point increase in municipal BFP coverage was associated with a 0.3% decrease in the incidence of malaria (RR = 0.997; 95% CI = 0.994–0.998). The average municipal BFP coverage increased 24 percentage points over the period 2004–2015 corresponding to be a reduction of 7.2% in the malaria incidence. Conclusions Higher coverage of the BFP was associated with a reduction in the incidence of malaria. CCT programmes should be encouraged in endemic regions for malaria in order to mitigate the impact of disease and poverty itself in these settings.

There has been a dramatic increase in the frequency of arboviral disease epidemics among humans and domestic animals worldwide in recent decades. Some of these infections have also undergone significant geographical expansion owing to uncontrolled urbanization leading to changes in vector distribution and/or adaptation of the etiologic agent to more anthropophilic vectors. Arboviral infections such as chikungunya have re-emerged in certain parts of the world, such as India (where chikungunya re-emerged in 2006 after 32 years of quiescence). Existing surveillance systems for arboviral infections in developing countries face several issues, such as being dependent on reporting of loosely defined clinical syndromes and infrequent laboratory confirmation. The recent re-emergence of Zika virus infections and its complications in South America underscore the urgent need for advancements in scientific knowledge on the biology of the arboviral agents and their vectors, innovations concerning diagnostic technologies, vector control measures, and therapeutic approaches. India, a tropical country, harbors an abundance of arthropod vectors capable of hosting and propagating viral infections. These vectors can transmit infections within humans, animals and also across species. This review focuses on viral infections in humans transmitted by arthropod vectors. [ABSTRACT FROM AUTHOR]

In the summer of 2007, an outbreak of Chikungunya virus (CHIKV) started in the urban areas of Castiglione di Cervia (Latitude 44°15′35.70" N, Longitude 12°15′47.08" E) and Castiglione di Ravenna (Latitude 44°15′33.97" N, Longitude 12°15′17.97" E), Italy, with secondary foci in other Emilia-Romagna urban areas. At the end of the outbreak a total of 217 confirmed cases were reported (45.6% males, 54.4% females). Aedes albopictus was identified as the mosquito vector species responsible of the outbreak. To estimate the dispersion of infected female mosquitoes, a spatio-temporal analysis on geocoded human case residences was performed using a Geographic Information System (QGIS 3.10). The mean distance between the primary and secondary cases after 7–14 days from the start of the outbreak ranged from 71.58 m (± 32.26 SD) to 83.07 m (± 32.26 SD) while the maximum distance ranged from 130.50 m to 174.93 m. The results obtained from this analysis can be useful to better understand the dynamics of the outbreak and to provide evidence-based data for planning emergence vector control activities focused on imported cases, to avoid the spread of the virus. [ABSTRACT FROM AUTHOR]

West Nile fever is a vector borne viral disease that can affect humans, horses, birds and sometimes other species of animals. Every year West Nile fever is detected in the human population in Serbia. The disease often occurs in a subclinical form, but most clinically evident cases occur in horses. Therefore, horses are recommended as a sentinel species for monitoring the general incidence of West Nile fever in a specific territory. Our goal was to determine the prevalence of antibodies against West Nile fever virus in horses in the Belgrade epizootiological area. We examined serum samples from 77 horses to determine the seroprevalence of West Nile fever virus in horses throughout the city of Belgrade. Sera were tested by commercial ELISA tests for detection of specific IgG-class antibodies to West Nile fever virus and for the detection of specific IgM-class antibodies to confirm the presence of old and acute (recent) infections in horses. The results confirmed that West Nile fever virus is widespread, detected in 70.1% of the surveyed horse population in Belgrade, and we also detected 5.1% of acute cases had occurred due to horses being infected in 2019. The seroprevalence of West Nile virus in the horse population in the municipality of Belgrade is increasing.

Background and objectives: Rocky Mountain spotted fever (RMSF) is a rapidly progressive and potentially fatal tickborne disease caused by Rickettsia rickettsii. Despite current recommendations and information on the severity of RMSF, studies show that delayed recognition and treatment continues to occur. Methods: A literature search was performed on cases published in English between 1990–2017. The frequencies for demographic, clinical, and treatment variables was calculated. Results: A total of 340 cases from 34 articles were included. Data on rash were available for 322 patients, and 261 (80%) noted rash. Mortality was 4% (2) in those who received doxycycline within the first five days of illness, and 35% (18) when treatment was delayed beyond Day five. Twenty-four (16%) reported chronic sequelae, including speech impairment (7, 5%) and ataxia (5, 3%). Interpretation and conclusion: These data highlight the importance of early treatment, and add to our understanding of long-term sequelae. Early recognition by providers will facilitate appropriate treatment and reduction in morbidity and mortality.

The CYD-TDV vaccine was recently developed to combat dengue, a mosquito-borne viral disease that afflicts millions of people each year throughout the tropical and subtropical world. Its rollout has been complicated by recent findings that vaccinees with no prior exposure to dengue virus (DENV) experience an elevated risk of severe disease in response to their first DENV infection subsequent to vaccination. As a result of these findings, guidelines for use of CYD-TDV now require serological screening prior to vaccination to establish that an individual does not fall into this high-risk category. These complications mean that the public health impact of CYD-TDV vaccination is expected to be higher in areas with higher transmission. One important practical difficulty with tailoring vaccination policy to local transmission contexts is that DENV transmission is spatially heterogeneous, even at the scale of neighborhoods or blocks within a city. This raises the question of whether models based on data that average over spatial heterogeneity in transmission could fail to capture important aspects of CYD-TDV impact in spatially heterogeneous populations. We explored this question with a deterministic model of DENV transmission and CYD-TDV vaccination in a population comprised of two communities with differing transmission intensities. Compared to the full model, a version of the model based on the average of the two communities failed to capture benefits of targeting the intervention to the high-transmission community, which resulted in greater impact in both communities than we observed under even coverage. In addition, the model based on the average of the two communities substantially overestimated impact among vaccinated individuals in the low-transmission community. In the event that the specificity of serological screening is not high, this result suggests that models that ignore spatial heterogeneity could overlook the potential for harm to this segment of the population.

This study focuses on 171 university students’ level of knowledge, perceptions and practices regarding Zika virus and its vector in Santa Marta (Colombia) in 2016. A survey was conducted and answers about causative agent and mode of transmission were classified into three levels of knowledge. 32.1% of the students stated that they had suffered from Zika. A 60% stated that they knew what the disease was, however, only 29.2% knew what the causative agent was and 45.6% knew the mode of transmission. Regarding the level of knowledge, only 14.6% knew the causative agent and the mode of transmission (Level 2). In general, the students recognize Zika’s symptoms, and 53.8% consider Zika to be very serious and more than half consider that they, the community and the government are responsible for controlling the vector. Even though more than half the students know the most important strategies as regards on how to control the vector, they do not practice them; this may be explained by the characteristics of their daily live dynamics, the lack of community organization, deficiency in the system of public health and climate change. It is recommended to implement permanent vector control strategies that consider the sociocultural characteristics of at-risk populations.

[Display omitted] • Avian malaria prevalence increases with deforestation across the Atlantic Forest. • Plasmodium prevalence increases with diminishing host functional diversity. • Reduction in host functional diversity also increases Plasmodium lineage richness. • Plasmodium lineage richness increases with avian host diversity. • Landscape anthropogenic changes impact avian malaria prevalence and diversity. Host phylogenetic relatedness and ecological similarity are thought to contribute to parasite community assembly and infection rates. However, recent landscape level anthropogenic changes may disrupt host-parasite systems by impacting functional and phylogenetic diversity of host communities. We examined whether changes in host functional and phylogenetic diversity, forest cover, and minimum temperature influence the prevalence, diversity, and distributions of avian haemosporidian parasites (genera Haemoproteus and Plasmodium) across 18 avian communities in the Atlantic Forest. To explore spatial patterns in avian haemosporidian prevalence and taxonomic and phylogenetic diversity, we surveyed 2241 individuals belonging to 233 avian species across a deforestation gradient. Mean prevalence and parasite diversity varied considerably across avian communities and parasites responded differently to host attributes and anthropogenic changes. Avian malaria prevalence (termed herein as an infection caused by Plasmodium parasites) was higher in deforested sites, and both Plasmodium prevalence and taxonomic diversity were negatively related to host functional diversity. Increased diversity of avian hosts increased local taxonomic diversity of Plasmodium lineages but decreased phylogenetic diversity of this parasite genus. Temperature and host phylogenetic diversity did not influence prevalence and diversity of haemosporidian parasites. Variation in the diversity of avian host traits that promote parasite encounter and vector exposure (host functional diversity) partially explained the variation in avian malaria prevalence and diversity. Recent anthropogenic landscape transformation (reduced proportion of native forest cover) had a major influence on avian malaria occurrence across the Atlantic Forest. This suggests that, for Plasmodium , host phylogenetic diversity was not a biotic filter to parasite transmission as prevalence was largely explained by host ecological attributes and recent anthropogenic factors. Our results demonstrate that, similar to human malaria and other vector-transmitted pathogens, prevalence of avian malaria parasites will likely increase with deforestation. [ABSTRACT FROM AUTHOR]

Background: Malaria causes 400 thousand deaths worldwide annually. In 2018, 25% (187,693) of the total malaria cases in the Americas were in Brazil, with nearly all (99%) Brazilian cases in the Amazon region. The Bolsa Família Programme (BFP) is a conditional cash transfer (CCT) programme launched in 2003 to reduce poverty and has led to improvements in health outcomes. CCT programmes may reduce the burden of malaria by alleviating poverty and by promoting access to healthcare, however this relationship is underexplored. This study investigated the association between BFP coverage and malaria incidence in Brazil.Methods: A longitudinal panel study was conducted of 807 municipalities in the Brazilian Amazon between 2004 and 2015. Negative binomial regression models adjusted for demographic and socioeconomic covariates and time trends were employed with fixed effects specifications.Results: A one percentage point increase in municipal BFP coverage was associated with a 0.3% decrease in the incidence of malaria (RR = 0.997; 95% CI = 0.994-0.998). The average municipal BFP coverage increased 24 percentage points over the period 2004-2015 corresponding to be a reduction of 7.2% in the malaria incidence.Conclusions: Higher coverage of the BFP was associated with a reduction in the incidence of malaria. CCT programmes should be encouraged in endemic regions for malaria in order to mitigate the impact of disease and poverty itself in these settings. [ABSTRACT FROM AUTHOR]

Alappuzha coastal district was worst affected by floods due to the heavy rainfall in August 2018. Aedes albopictus survey carried out in the post flood/ disaster areas covering 1,140 households revealed maximum larval positivity in plastic/leather followed by metal and earthen containers. The House index ranged from 1.75 to 12.28 per cent whereas the container index ranged from 1.73 to 20.51 per cent. Breteau index ranged from 3.5 to14.3. As dengue is endemic in the district, there exists a potential outbreak of the vector borne disease. [ABSTRACT FROM AUTHOR]

Abstract EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases (‘Animal Health Law’). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for African Horse Sickness (AHS). In this opinion, EFSA and the AHAW Panel of experts review the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum duration of measures in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, specific details of the transmission kernels used for the assessment of the minimum radius of the protection and surveillance zones are shown. Several scenarios for which these control measures were assessed were designed and agreed prior to the start of the assessment. In summary, sampling procedures described in the diagnostic manual for AHS were considered efficient for all Equidae considering the high case fatality rate expected. The monitoring period (14 days) was assessed as effective in every scenario, except for those relating to the epidemiological enquiry where the risk manager should consider increasing the monitoring period, based on the awareness of keepers, environmental conditions and the vector abundance in the region. The current protection zone (100 km) comprises more than 95% of the infections from an affected establishment. Both the radius and duration of the zones could be reduced, based on local environmental conditions and the time of year of the first index case. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation relating to AHS.

Abstract EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases (‘Animal Health Law’). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for African Swine Fever (ASF). In this opinion, EFSA and the AHAW Panel of experts reviewed the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum length of time the measures should be applied in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, specific details of the model used for the assessment of the laboratory sampling procedures for ASF are presented here. Here, also, the transmission kernels used for the assessment of the minimum radius of the protection and surveillance zones are shown. Several scenarios for which these control measures had to be assessed were designed and agreed prior to the start of the assessment. In summary, several sampling procedures as described in the diagnostic manual for ASF were considered ineffective and a suggestion to exclude, or to substitute with more effective procedures was made. The monitoring period was assessed as non‐effective for several scenarios and a longer monitoring period was suggested to ensure detection of potentially infected herds. It was demonstrated that the surveillance zone comprises 95% of the infections from an affected establishment, and therefore is considered effective. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation, as well as for plausible ad hoc requests in relation to ASF.

EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases ('Animal Health Law'). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for African Horse Sickness (AHS). In this opinion, EFSA and the AHAW Panel of experts review the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum duration of measures in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, specific details of the transmission kernels used for the assessment of the minimum radius of the protection and surveillance zones are shown. Several scenarios for which these control measures were assessed were designed and agreed prior to the start of the assessment. In summary, sampling procedures described in the diagnostic manual for AHS were considered efficient for all Equidae considering the high case fatality rate expected. The monitoring period (14 days) was assessed as effective in every scenario, except for those relating to the epidemiological enquiry where the risk manager should consider increasing the monitoring period, based on the awareness of keepers, environmental conditions and the vector abundance in the region. The current protection zone (100 km) comprises more than 95% of the infections from an affected establishment. Both the radius and duration of the zones could be reduced, based on local environmental conditions and the time of year of the first index case. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation relating to AHS. [ABSTRACT FROM AUTHOR]

EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases ('Animal Health Law'). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for African Swine Fever (ASF). In this opinion, EFSA and the AHAW Panel of experts reviewed the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum length of time the measures should be applied in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, specific details of the model used for the assessment of the laboratory sampling procedures for ASF are presented here. Here, also, the transmission kernels used for the assessment of the minimum radius of the protection and surveillance zones are shown. Several scenarios for which these control measures had to be assessed were designed and agreed prior to the start of the assessment. In summary, several sampling procedures as described in the diagnostic manual for ASF were considered ineffective and a suggestion to exclude, or to substitute with more effective procedures was made. The monitoring period was assessed as non-effective for several scenarios and a longer monitoring period was suggested to ensure detection of potentially infected herds. It was demonstrated that the surveillance zone comprises 95% of the infections from an affected establishment, and therefore is considered effective. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation, as well as for plausible ad hoc requests in relation to ASF. [ABSTRACT FROM AUTHOR]

The identification of areas of health and disease zones of Madurai city can lead one to associate the factors of social and physical environment that are identified with both. The spatial distribution of diseases is still a matter of importance and mapping plays a huge role in the field. Dengue is a viral disease transmitted by the Aedes aegypti mosquito. Dengue has become an important public health problem worldwide. It affects tropical and subtropical regions around the world, predominantly urban and semi urban areas. The present study considers the potential impact of vector borne infections on human health. In Madurai, dengue fever and dengue hemorrhagic fever have shown an increasing trend. The study area of Madurai is located in South Tamilnadu, India. This study aimed to map the spatial distribution of dengue cases in Madurai city. This study analyzed dengue cases from 2013 to 2015 in different precincts of Madurai city. The main aim of this study is to locate the distribution of vector born diseases in the study area and associate with "Z" Score variation based on GIS techniques. Identification and interpretation of spatial variations resulting from such distribution suitable policies and decisions for an effective health care planning. The study has shown that by using GIS; it's possible to improve the understanding of the distribution of dengue cases within a particular area. GIS and spatial statistical analyses are important in guiding health agencies, epidemiologists, public health officers, town planners and relevant authorities in developing efficient control measures and contingency programs in identifying and prioritizing their efforts in effective dengue control activities. [ABSTRACT FROM AUTHOR]

Maintenance of Borrelia burgdorferi within its enzootic cycle requires a complex regulatory pathway involving the alternative σ factors RpoN and RpoS and two ancillary trans-acting factors, BosR and Rrp2. Activation of this pathway occurs within ticks during the nymphal blood meal when RpoS, the effector σ factor, transcribes genes required for tick transmission and mammalian infection. RpoS also exerts a ‘gatekeeper’ function by repressing σ70-dependent tick phase genes (e.g., ospA, lp6.6). Herein, we undertook a broad examination of RpoS functionality throughout the enzootic cycle, beginning with modeling to confirm that this alternative σ factor is a ‘genuine’ RpoS homolog. Using a novel dual color reporter system, we established at the single spirochete level that ospA is expressed in nymphal midguts throughout transmission and is not downregulated until spirochetes have been transmitted to a naïve host. Although it is well established that rpoS/RpoS is expressed throughout infection, its requirement for persistent infection has not been demonstrated. Plasmid retention studies using a trans-complemented ΔrpoS mutant demonstrated that (i) RpoS is required for maximal fitness throughout the mammalian phase and (ii) RpoS represses tick phase genes until spirochetes are acquired by a naïve vector. By transposon mutant screening, we established that bba34/oppA5, the only OppA oligopeptide-binding protein controlled by RpoS, is a bona fide persistence gene. Lastly, comparison of the strain 297 and B31 RpoS DMC regulons identified two cohorts of RpoS-regulated genes. The first consists of highly conserved syntenic genes that are similarly regulated by RpoS in both strains and likely required for maintenance of B. burgdorferi sensu stricto strains in the wild. The second includes RpoS-regulated plasmid-encoded variable surface lipoproteins ospC, dbpA and members of the ospE/ospF/elp, mlp, revA, and Pfam54 paralogous gene families, all of which have evolved via inter- and intra-strain recombination. Thus, while the RpoN/RpoS pathway regulates a ‘core’ group of orthologous genes, diversity within RpoS regulons of different strains could be an important determinant of reservoir host range as well as spirochete virulence.

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Maintenance of Borrelia burgdorferi within its enzootic cycle requires a complex regulatory pathway involving the alternative σ factors RpoN and RpoS and two ancillary trans -acting factors, BosR and Rrp2. Activation of this pathway occurs within ticks during the nymphal blood meal when RpoS, the effector σ factor, transcribes genes required for tick transmission and mammalian infection. RpoS also exerts a 'gatekeeper' function by repressing σ70-dependent tick phase genes (e.g., ospA , lp6.6). Herein, we undertook a broad examination of RpoS functionality throughout the enzootic cycle, beginning with modeling to confirm that this alternative σ factor is a 'genuine' RpoS homolog. Using a novel dual color reporter system, we established at the single spirochete level that ospA is expressed in nymphal midguts throughout transmission and is not downregulated until spirochetes have been transmitted to a naïve host. Although it is well established that rpoS /RpoS is expressed throughout infection, its requirement for persistent infection has not been demonstrated. Plasmid retention studies using a trans -complemented Δ rpoS mutant demonstrated that (i) RpoS is required for maximal fitness throughout the mammalian phase and (ii) RpoS represses tick phase genes until spirochetes are acquired by a naïve vector. By transposon mutant screening, we established that bba34/oppA5 , the only OppA oligopeptide-binding protein controlled by RpoS, is a bona fide persistence gene. Lastly, comparison of the strain 297 and B31 RpoS DMC regulons identified two cohorts of RpoS-regulated genes. The first consists of highly conserved syntenic genes that are similarly regulated by RpoS in both strains and likely required for maintenance of B. burgdorferi sensu stricto strains in the wild. The second includes RpoS-regulated plasmid-encoded variable surface lipoproteins ospC , dbpA and members of the ospE/ospF/elp , mlp , revA , and Pfam54 paralogous gene families, all of which have evolved via inter- and intra-strain recombination. Thus, while the RpoN/RpoS pathway regulates a 'core' group of orthologous genes, diversity within RpoS regulons of different strains could be an important determinant of reservoir host range as well as spirochete virulence. [ABSTRACT FROM AUTHOR]

Parasites with low host specificity (e.g. infecting a large diversity of host species) are of special interest in disease ecology, as they are likely more capable of circumventing ecological or evolutionary barriers to infect new hosts than are specialist parasites. Yet for many parasites, host specificity is not fixed and can vary in response to environmental conditions. Using data on host associations for avian malaria parasites (Apicomplexa: Haemosporida), we develop a hierarchical model that quantifies this environmental dependency by partitioning host specificity variation into region‐ and parasite‐level effects. Parasites were generally phylogenetic host specialists, infecting phylogenetically clustered subsets of available avian hosts. However, the magnitude of this specialisation varied biogeographically, with parasites exhibiting higher host specificity in regions with more pronounced rainfall seasonality and wetter dry seasons. Recognising the environmental dependency of parasite specialisation can provide useful leverage for improving predictions of infection risk in response to global climate change. [ABSTRACT FROM AUTHOR]

Abstract Dengue dynamics are shaped by the complex interplay between several factors, including vector seasonality, interaction between four virus serotypes, and inapparent infections. However, paucity or quality of data do not allow for all of these to be taken into account in mathematical models. In order to explore separately the importance of these factors in models, we combined surveillance data with a local-scale cluster study in the rural province of Kampong Cham (Cambodia), in which serotypes and asymptomatic infections were documented. We formulate several mechanistic models, each one relying on a different set of hypotheses, such as explicit vector dynamics, transmission via asymptomatic infections and coexistence of several virus serotypes. Models are confronted with the observed time series using Bayesian inference, through Markov chain Monte Carlo. Model selection is then performed using statistical information criteria, and the coherence of epidemiological characteristics (reproduction numbers, incidence proportion, dynamics of the susceptible classes) is assessed in each model. Our analyses on transmission dynamics in a rural endemic setting highlight that two-strain models with interacting effects better reproduce the long term data, but they are difficult to parameterize when relying on incidence cases only. On the other hand, considering the available data, incorporating vector and asymptomatic components seems of limited added-value when seasonality and underreporting are already accounted for. [ABSTRACT FROM AUTHOR]

In Tasmania, a temperate island state of Australia, there is little understood about the human health implications of a changing climate. Here, we investigate the hypothesis that human populations in Tasmania might become more vulnerable to Ross River virus (RRV) under climate change, Australia’s most significant vector-borne disease. Importantly, our study considers the complex social-ecological systems based setting that this virus represents, with our approach being underpinned by systems thinking. Specifically, we undertake an integrated and participatory assessment of potential human vulnerability to RRV in a changing climate, and taking account of other parallel, non-climate regional-scale change considerations. We show that projected moderate changes in Tasmania’s climate will have implications for the State’s human health, whereby Tasmania is likely to become more vulnerable to RRV as the 21st Century progresses, shifting this health issue from a relatively low public health risk to one that will become more concerning and costly. The study assists us to contemplate how we frame human health questions as we move into a climatically changing world and reminds us that health impacts will not always be linear or obvious. It demonstrates an approach for scoping indirect and potentially insidious implications of climate change, even in the face of uncertainty, imperfect systems understanding, and limited resources, to inform a range of decision makers.

The clinical association between Coxsackievirus B (CVB) and methicillin-sensitive Staphylococcus aureus (MSSA) has not been well established in the current literature. Here, we report a case of a 29-year-old male who presented with fever and malaise 24 hours after noticing a pruritic lesion on the anterior foreleg that resembled a mosquito bite. After multiple ED visits, laboratory studies, and imaging tests, the patient was admitted for treatment of high fevers and pancytopenia. The final diagnosis was viral sepsis complicated by co-infection with MSSA., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Ethridge et al.)

Leishmaniasis is a neglected tropical vector-borne epidemic disease, and its transmission is a complex process. Zoonotic transmission to humans or animals occurs through the bites of female Phlebotominae sand flies. Here, reservoir is considered as a major source of endemic pathogen pool for disease outbreak, and the role of more than one reservoir animal becomes indispensable. To study the role of the reservoir animals on disease dynamics, a mathematical model was constructed consisting of susceptible and infected populations of humans and two types of reservoir (animal) and vector populations, respectively. Our aim is to prevent the disease by applying a control theoretic approach, when more than one type of reservoir animal exists in the region. We use drugs like sodium stibogluconate and meglumine antimoniate to control the disease for humans and spray insecticide to control the sand fly population. Similarly, drugs are applied for infected reservoir animals of Types A and B. We calculated the cost-effectiveness of all possible combinations of the intervention and control policies. One of our findings is that the most cost-effective case for Leishmania control is the spray of insecticides for infected sand fly vector. Alternate strategic cases were compared to address the critical shortcomings of single strategic cases, and a range of control strategies were estimated for effective control and economical benefit of the overall control strategy. Our findings provide the most innovative techniques available for application to the successful eradication of cutaneous leishmaniasis in the future.