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Japanese encephalitis virus (JEV), an important neurotropic pathogen, belongs to the genus Flavivirus of the family Flaviviridae and has caused huge threat to public health. It is still obscure regarding the functions of stem-loop (SL) and dumbbell (DB) domains of JEV 3��� UTR in viral replication and virulence. In the current study, using the infectious clone of JEV SA14 strain as a backbone, we constructed a series of deletion mutants of 3��� UTR to investigate their effects on virus replication. The results showed that partial deletions within SL or DB domain had no apparent effects on virus replication in both mammalian (BHK-21) and mosquito (C6/36) cells, suggesting that they were not involved in viral host-specific replication. However, the entire SL domain deletion (��VR) significantly reduced virus replication in both cell lines, indicating the important role of the complete SL domain in virus replication. The revertant of ��VR mutant virus was obtained by serial passage in BHK-21 cells that acquired a duplication of DB domain (DB-dup) in the 3��� UTR, which greatly restored virus replication as well as the capability to produce the subgenomic flavivirus RNAs (sfRNAs). Interestingly, the DB-dup mutant virus was highly attenuated in C57BL/6 mice despite replicating similar to WT JEV. These findings demonstrate the significant roles of the duplicated structures in 3��� UTR in JEV replication and provide a novel strategy for the design of live-attenuated vaccines.

Artemisinin (ARS) and its semi-synthetic derivatives are effective drugs to treat malaria and possess multiple therapeutic activities based on their endoperoxide bridge. Here, we showed that ARS displayed antibacterial efficacy in Drosophila systemic infections caused by bacterial pathogens but killed only Vibrio cholerae (VC) in vitro, involving reactive oxygen species (ROS) generation and/or DNA damage. This selective antibacterial activity of ARS was attributed to the higher intracellular copper levels in VC, in that the antibacterial activity was observed in vitro upon addition of cuprous ions even against other bacteria and was compromised by the copper-specific chelators neocuproine (NC) and triethylenetetramine (TETA) in vitro and in vivo. We suggest that copper can enhance or reinforce the therapeutic activities of ARS to be repurposed as an antibacterial drug for the treatment of bacterial infections.

Breakthrough infection of SARS-CoV-2 is a serious challenge, as increased infections were documented in fully-vaccinated individuals. Recipients with poor antibody response are highly vulnerable to reinfection, whereas those with strong antibody responses achieve sterilizing immunity. Thus far, biomarkers associated with levels of vaccine-elicited antibody response are still lacking. Here, we studied the antibody response of age- and gender-controlled healthy cohort, who received inactivated SARS-CoV-2 vaccines and profiled the B cell receptor repertoires in longitudinally consecutive samples. Upon vaccination, all vaccinated individuals displayed a convergent antibody response with shared common antibody clones and public neutralizing antibodies. Strikingly, poor vaccine-responders are distinguishable from strong vaccine-responders by a biased V-usage before vaccination and IgG to IgM mRNA ratio. These findings reveal molecular signatures associated with the different levels of vaccine-induced antibody response, which could be further developed into biomarkers for the design of vaccination strategies.

On 30 June 2021, China was certified malaria-free by the World Health Organization. In this study, the evolution, performance, outcomes, and impact of China’s adaptive strategy and approach for malaria elimination from 2011 to 2020 were analysed using 10-year data. The strategy and approach focused on timely detection and rapid responses to individual cases and foci. Indigenous cases declined from 1,308 in 2011 to 36 in 2015, and the last one was reported from Yunnan Province in April 2016, although thousands of imported cases still occur annually. The “1–3–7” approach was implemented successfully between 2013 and 2020, with 100% of cases reported within 24 h, 94.5% of cases investigated within three days of case reporting, and 93.4% of foci responses performed within seven days. Additionally, 81.6% of patients attended the first healthcare visit within 1–3 days of onset and 58.4% were diagnosed as malaria within three days of onset, in 2017–2020. The adaptive strategy and approach, along with their universal implementation, are most critical in malaria elimination. In addition to strengthening surveillance on drug resistance and vectors and border malaria collaboration, a further adapted three-step strategy and the corresponding “3–3–7” model are recommended to address the risks of re-transmission and death by imported cases after elimination. China’s successful practice and lessons learnt through long-term efforts provide a reference for countries moving towards elimination.

Tuberculosis (TB) is the leading infectious disease caused by Mycobacterium tuberculosis (Mtb). Clarithromycin (CTY), an analog of erythromycin (ERY), is more potent against multidrug-resistance (MDR) TB. ERY and CTY were previously reported to bind to the nascent polypeptide exit tunnel (NPET) near peptidyl transferase center (PTC), but the only available CTY structure in complex with D. radiodurans (Dra) ribosome could be misinterpreted due to resolution limitation. To date, the mechanism of specificity and efficacy of CTY for Mtb remains elusive since the Mtb ribosome-CTY complex structure is still unknown. Here, we employed new sample preparation methods and solved the Mtb ribosome-CTY complex structure at 3.3�� with cryo-EM technique, where the crucial gate site A2062 (E. coli numbering) is located at the CTY binding site within NPET. Two alternative conformations of A2062, a novel syn-conformation as well as a swayed conformation bound with water molecule at interface, may play a role in coordinating the binding of specific drug molecules. The previously overlooked C���H hydrogen bond (H-bond) and �� interaction may collectively contribute to the enhanced binding affinity. Together, our structure data provide a structural basis for the dynamic binding as well as the specificity of CTY and explain of how a single methyl group in CTY improves its potency, which provides new evidence to reveal previously unclear mechanism of translational modulation for future drug design and anti-TB therapy. Furthermore, our sample preparation method may facilitate drug discovery based on the complexes with low water solubility drugs by cryo-EM technique.

Emerging studies indicate that infusion of HIV-resistant cells could be an effective strategy to achieve a sterilizing or functional cure. We recently reported that glycosylphosphatidylinositol (GPI)-anchored nanobody or a fusion inhibitory peptide can render modified cells resistant to HIV-1 infection. In this study, we comprehensively characterized a panel of newly isolated HIV-1-neutralizing antibodies as GPI-anchored inhibitors. Fusion genes encoding the single-chain variable fragment (scFv) of 3BNC117, N6, PGT126, PGT128, 10E8, or 35O22 were constructed with a self-inactivating lentiviral vector, and they were efficiently expressed in the lipid raft sites of target cell membrane without affecting the expression of HIV-1 receptors (CD4, CCR5 and CXCR4). Significantly, transduced cells exhibited various degrees of resistance to cell-free HIV-1 infection and cell-associated HIV-1 transmission, as well as viral Env-mediated cell–cell fusion, with the cells modified by GPI-10E8 showing the most potent and broad anti-HIV activity. In mechanism, GPI-10E8 also interfered with the processing of viral Env in transduced cells and attenuated the infectivity of progeny viruses. By genetically linking 10E8 with a fusion inhibitor peptide, we subsequently designed a group of eight bifunctional constructs as cell membrane-based inhibitors, designated CMI01∼CMI08, which rendered cells completely resistant to HIV-1, HIV-2, and simian immunodeficiency virus (SIV). In human CD4+ T cells, GPI-10E8 and its bifunctional derivatives blocked both CCR5- and CXCR4-tropic HIV-1 isolates efficiently, and the modified cells displayed robust survival selection under HIV-1 infection. Therefore, our studies provide new strategies for generating HIV-resistant cells, which can be used alone or with other gene therapy approaches.

HIV-1 latency posts a major obstacle for HIV-1 eradication. Currently, no desirable latency reversing agents (LRAs) have been implicated in the “Shock and Kill” strategy to mobilize the latently infected cells to be susceptible for clearance by immune responses. Identification of key cellular pathways that modulate HIV-1 latency helps to develop efficient LRAs. In this study, we demonstrate that the Wnt downstream β-catenin/TCF1 pathway is a crucial modulator for HIV-1 latency. The pharmacological activation of the β-catenin/TCF1 pathway with glycogen synthase kinase-3 (GSK3) inhibitors promoted transcription of HIV-1 proviral DNA and reactivated latency in CD4+ T cells; the GSK3 kinase inhibitor 6-bromoindirubin-3′-oxime (6-BIO)-induced HIV-1 reactivation was subsequently confirmed in resting CD4+ T cells from cART-suppressed patients and SIV-infected rhesus macaques. These findings advance our understanding of the mechanisms responsible for viral latency, and provide the potent LRA that can be further used in conjunction of immunotherapies to eradicate viral reservoirs., GRAPHICAL ABSTRACT

The worldwide resurgence of tropical bed bug Cimex hemipterus beginning in the late 1990s has led to growing concern. Molecular data on pyrethroid resistance, which is essential for the control strategies, is unknown for C. hemipterus in Iran. The current study evaluated the deltamethrin resistance status of C. hemipterus by bioassay and molecular tests. Live bed bugs were collected from sleeping quarters (dormitories) in the city of Tehran and used for insecticide bioassay tests. For bioassay evaluation, mixed-sex pools of adult bugs were exposed to deltamethrin (0.025%)-treated paper. Polymerase chain reaction assay evaluated resistance-related mutations in the voltage-gated sodium channel gene (VGSC) gene of studied populations. On the basis of the bioassay test within the 48-h exposure to deltamethrin, C. hemipterus were determined to be resistant. Knockdown time ratios (KR50) in the studied populations of C. hemipterus was 5.5-fold compared with those of the C. lectularius Teh strain. DNA sequencing of the VGSC gene revealed the presence of mutations at M918I and L1014 in C. hemipterus. According to the bioassay and molecular results of current study, C. hemipterus showed a high degree of pyrethroid resistance. The application of multiple approaches including physical, biological, and chemical tests should be regarded in future bed bug control strategies.

Understanding the reservoir and infectivity of Plasmodium gametocytes to vector mosquitoes is crucial to align strategies aimed at malaria transmission elimination. Yet, experimental information is scarce regarding the infectivity of Plasmodium vivax for mosquitoes in diverse epidemiological settings where the proportion of asymptomatically infected individuals varies at a microgeographic scale. We measured the transmissibility of clinical and subclinical P. vivax malaria parasite carriers to the major mosquito vector in the Amazon Basin, Nyssorhynchus darlingi (formerly Anopheles). A total of 105 participants with natural P. vivax malaria infection were recruited from a cohort study in Loreto Department, Peruvian Amazon. Four of 18 asymptomatic individuals with P. vivax positivity by blood smear infected colony-grown Ny. darlingi (22%), with 2.6% (19 of 728) mosquitoes infected. In contrast, 77% (44/57) of symptomatic participants were infectious to mosquitoes with 51% (890 of 1,753) mosquitoes infected. Infection intensity was greater in symptomatic infections (mean, 17.8 oocysts/mosquito) compared with asymptomatic infections (mean, 0.28 oocysts/mosquito), attributed to parasitemia/gametocytemia level. Paired experiments (N = 27) using direct skin-feeding assays and direct membrane mosquito-feeding assays showed that infectivity to mosquitoes was similar for both methods. Longitudinal studies with longer follow-up of symptomatic and asymptomatic parasite infections are needed to determine the natural variations of disease transmissibility.

Substandard and falsified medicines are an enormous threat to global health. Poor quality antibiotic preparations contribute to the development of antimicrobial resistance. In surgery, where the occurrence of healthcare-associated infections is high, healthcare teams need to rely on the quality of antibiotic prophylaxis to prevent infections. We assessed the quality of antibiotics used for surgical infection prophylaxis in Benin. Thirty-three samples were collected from six hospitals located in various departments in Benin. The antibiotics (powders for injection: amoxicillin + clavulanic acid, ampicillin, ceftriaxone; solutions for injection: ciprofloxacin, gentamicin, metronidazole) were assessed using visual inspection, pharmacotechnical tests (including uniformity of mass, pH measure, sterility test, and active pharmaceutical ingredient identification), and assay tests (including a simple analytical method thin layer chromatography) and complex analytical techniques (ultraviolet-visible spectrophotometry, high-performance liquid chromatography—diode-array detection, conductometry). Because the material needed for the methods recommended by the pharmacopeias to assess the dosage of gentamicin was not available, we developed and validated a conductometry method. Results showed that 97% (n = 32) of the samples passed visual inspection; 100% (n = 33) of the samples passed the pharmacotechnical tests, identification of active ingredients, and sterility test; 88% (n = 29) passed the test for percentage of active pharmaceutical ingredients. Overall, 15% of the samples did not pass the quality test (3% on visual inspection and 12% for excess active ingredients). Although most of the samples passed the quality tests, it appears important to perform routine quality control for intravenous medicines.

A changing clinical scenario of dermatophytosis has been observed in Sri Lanka during the past few years. In keeping with the trend described in India, an increase in the number of chronic, relapsing, and recalcitrant infections has been noted. The objective of our study was to assess the therapeutic response of dermatophytosis to standard antifungal treatment in Sri Lanka and to identify possible contributory factors in cases showing inadequate therapeutic response. A descriptive, observational, cross-sectional study was carried out in nine hospitals, representing each province. Over 6 months, patients with dermatophytosis on glabrous skin were included. All subjects underwent skin scrapings for mycological studies and were treated with a standard course of antifungals for a specific period. In those patients who achieved complete clearance, recurrences were noted. The study included 796 patients, of whom 191 (24%) had symptoms for more than 3 months at presentation. A total of 519 patients (65.2%) had multiple-site involvement, and 503 (63.2%) had evidence of prior use of topical steroids. Skin scrapings were positive for fungal elements in the direct smears of 659 patients (82.8%), and the predominant dermatophyte isolated was Trichophyton mentagrophytes (65.6%). Partial responders after 10 weeks of treatment and recurrences after complete clearance were significantly greater in the group that used topical steroids before presentation (P < 0.001). This study highlights the magnitude of the threat of an inadequate therapeutic response in dermatophytosis in Sri Lanka, and identifies steroid misuse, and the shift of the predominant fungal species to T. mentagrophytes as possible causative factors.

Chagas disease caused by Trypanosoma cruzi, remains one of the leading public health problems in Latin America. The number of infections in nonendemic countries continues to rise as a consequence of migratory flows. Updated information on prevalence, especially in treatable stages, together with vector eradication programs are key factors in an attempt to control the disease. We aim to estimate the prevalence of T. cruzi infection in an endemic area of Argentina and to describe epidemiological and clinical factors related to the disease. This is a cross-sectional study in an endemic rural area of Argentina. Our target population was people between 10 and 20 years of age, collecting demographic, clinical, and electrocardiographic data and seroprevalence against T. cruzi. We included 460 subjects; 76.7% did not have drinking water; 49.3% reported the presence of Triatoma infestans at home; 79.1% had pets or birds; 72.6% lived close to a chicken coop; 24.6% lived in adobe houses; 27.8% lived in overcrowded conditions. Seroprevalence was 9.33%. In the multivariate analysis, the presence of Triatoma infestans at home (OR 2.08, P = 0.03) had an association with seropositivity. No relevant findings indicating acute or chronic organ involvement were detected. We found no correlation of right bundle branch block (RBBB) and Chagas disease in our population. None of the infected patients were previously aware of their condition, highlighting the importance of active surveillance to detect infection in a potentially treatable stage, especially in areas with difficult access to health programs.

We used data on the species composition of regional assemblages of fleas and their small mammalian hosts from 6 biogeographic realms and applied a novel method of step-down factor analyses (SDFA) and cluster analyses to identify biogeographic (across the entire globe) and ecological (within a realm across the main terrestrial biomes) clusters of these assemblages. We found that, at the global scale, the clusters of regional assemblage loadings on SDFA axes reflected well the assemblage distribution, according to the biogeographic realms to which they belong. At the global scale, the cluster topology, corresponding to the biogeographic realms, was similar between flea and host assemblages, but the topology of subtrees within realm-specific clusters substantially differed between fleas and hosts. At the scale of biogeographic realms, the distribution of regional flea and host assemblages did not correspond to the predominant biome types. Assemblages with similar loadings on SDFA axes were often situated in different biomes and vice versa. The across-biome, within-realm distributions of flea vs host assemblages suggested weak congruence between these distributions. Our results indicate that dispersal is a predominant mechanism of flea and host community assembly across large regions.

In 2019, a new variant of coronavirus, SARS-CoV-2 (COVID-19) created a global pandemic that has highlighted and exacerbated health disparities. Educating the general public about COVID-19 is one of the primary mitigation strategies amongst health professionals. English is not the preferred language for an estimated 22% of the United States population making effective mass communication efforts difficult to achieve. This study seeks to understand and compare several topics surrounding COVID-19 health communication and healthcare disparities between individuals with English language preference (ELP) and non-English language preference (NELP) within the United States. A survey available in seven languages asking about knowledge and opinions on COVID-19, vaccines, preferred sources of health information, and other questions, was administered February-April 2021 to patients at an urban federally qualified health center that also serves global refugees and immigrants. Descriptive statistics and comparative analysis were performed to identify differences between ELP and NELP individuals. Analysis of 144 surveys, 33 of which were NELP, showed 90.97% of all patients agreed that COVID-19 was a serious disease and 66.67% would receive the COVID-19 vaccine. There were numerous differences between ELP and NELP individuals, including trust in government, symptom identification, preferred source of health information, and feelings that cultural needs had been met. This study has identified several significant differences in patient perceptions relating to the COVID-19 pandemic when comparing NELP to ELP and highlighted areas where improvement can occur. Applying this information, easily utilized targeted resources can be created to quickly intervene and address health disparities among patients seeking care at an urban community health center.

Malaria patients are at risk of cardiopulmonary complications but diagnosis and management can be difficult in resource-limited settings. B-lines on lung ultrasound (LUS) mark changes in lung density; however, little is known about their role in malaria. We aimed to examine the prevalence of B-lines in adults with malaria at baseline and follow-up compared with controls in the Amazon Basin. We also examined the relationship between B-lines and left ventricular ejection fraction. We performed eight-zone LUS, echocardiography, and blood smears in 94 adults (mean age 40 years, 54% men) with uncomplicated malaria and 449 controls without heart failure, renal insufficiency or lung disease (mean age 41 years, 38% men). Examinations of adults with malaria were repeated after antimalarial treatment, corresponding to a median of 30 days (interquartile range [IQR] 27–39). Adults with malaria suffered from Plasmodium vivax (N = 70, median 2,823 [IQR 598–7,698] parasites/μL) or P. falciparum (N = 24, median 1,148 [IQR 480–3,128] parasites/μL). At baseline, adults with malaria more frequently had ≥ 3 B-lines (summed across eight zones) compared with controls (30% versus 2%, P value < 0.001), indicating higher lung density. When examinations were repeated, only 6% of adults with malaria had ≥ 3 B-lines at follow-up, which was significant lower compared with baseline (median reduction 3 B-lines; P value < 0.001). B-lines were not significantly associated with left ventricular ejection fraction in adults with malaria. In conclusion, B-lines detected by LUS were more frequent in adults with uncomplicated malaria compared with controls and decreased after completed antimalarial treatment.

Behavioral economic principles are increasingly being used in the fight against HIV, including improving voluntary testing in sub-Saharan Africa and South America. However, behavioral nudges have not been widely tested as a strategy to optimize HIV testing in pregnant women. Here, we assessed whether behavioral nudges or financial incentives were effective in optimizing HIV testing among pregnant women in a high-HIV burden setting. A randomized clinical trial was conducted between May 21 and Oct 5, 2018, to allocate pregnant women in Ecuador into three study arms: information only, soft commitment (i.e., a behavioral nudge), and financial incentives. All participants received an informational flyer, including the address of a testing location. Participants in the soft-commitment arm signed and kept a form on which they committed to get tested for HIV. Those in the financial incentive arm received a $10 incentive when tested for HIV. A stepwise logistic regression analysis estimated the effect of the study arms on HIV testing rate. Participants in the financial-incentive arm had higher odds of getting an HIV test (adjusted odds ratio 17.06, P < 0.001) as compared with information-only participants. Soft-commitment had the opposite effect (adjusted odds ratio 0.14, P = 0.014). Financial incentives might be useful in improving HIV testing among pregnant women, especially among those who might be at higher risk but who have not completed an HIV test.

West Nile virus (WNV) IgM antibodies typically indicate a recent infection. However, WNV IgM antibodies can remain detectable for months to years following illness onset. We found that 23% (11/47) of samples tested with a WNV ELISA and 43% (20/47) of samples tested with WNV microsphere immunoassay (MIA) at 16–19 months following WNV illness onset were positive for IgM antibodies. The proportion of samples testing positive for WNV IgM by ELISA decreased over time, but 5% (2/44) of individuals remained positive at 60–63 months after their acute illness and 4% (2/50) were WNV IgM equivocal at 72–81 months. Testing by MIA showed the same general trend of decreased proportion positive over time though the rates of positivity were higher at most time points compared with the ELISA, including 6% (3/50) of participant’s samples identified as IgM positive by MIA at 72–81 months post their acute illness. With the MIA, there also was a high proportion of samples with nonspecific results at each time point; average of 23% across all time points. Clinicians and public health officials should consider these findings along with clinical and epidemiologic data when interpreting WNV IgM antibody test results.

Reports of increasing false-negative HRP2-based rapid diagnostic test results across Africa require constant monitoring of factors associated with these false-negative outcomes, as failure of this diagnostic tool will have severe consequences on malaria treatment and control programs. This study characterized the extent of genetic diversity in the Plasmodium falciparum histidine-rich protein 2 (Pfhrp2) gene in P. falciparum isolates from symptomatic malaria patients across the regions of Ghana. Exon 2 of Pfhrp2 was amplified from gDNA using polymerase chain reaction. All Pfhrp2-negative samples were subjected to Pf18S rRNA and Pfmsp2 gene amplifications. The amplified Pfhrp2 exon 2 fragments from clonal samples were sent for commercial Sanger sequencing. The type and number of PfHRP2 repeats, classified based on repeat types previously reported, were estimated from the sequence data and compared among geographical regions. About 81% (2,333/2,890) of the original microscopy positive dried blood spot (DBS) samples were available and used in this study. The Pfhrp2 exon 2 amplification was successful in 98.5% (2,297/2,333) of the tested samples, with band size ranging from 400 bp to 1,050 bp. A total of 13 out of the 24 previously reported repeat types were identified among the samples, with three samples lacking both type 2 and type 7 repeat motifs. This study suggested that the genetic diversity of Pfhrp2 exon 2 identified in P. falciparum circulating in symptomatic malaria patients in Ghana is unlikely to influence the sensitivity and specificity of HRP2 RDT-based diagnosis.

Human cystic echinococcosis (CE) in pregnancy is rarely reported, with approximately one case of CE for every 20,000 to 30,000 pregnant women in endemic areas. Little information on its management is available. We report our experience with a watch and wait approach in this group of patients. We retrieved clinical data from pregnant patients with hepatic CE seen at our clinic from 1989 to 2021. All patients had at least one hepatic CE cyst and received no treatment during pregnancy. Ultrasound was used to monitor cyst evolution; outcome and complications of pregnancy and echinococcal infection were evaluated. Twelve patients with 15 pregnancies were included in this study. At the time of pregnancy, nine patients had a single cyst and two patients had multiple hepatic CE cysts. Cysts were in stage CE3a, CE3b, CE4, and CE5, according to the WHO Informal Working Group on Echinococcosis classification. All cysts except one remained stable in stage and size during and after pregnancy. In one patient with a history of multiple treatments with albendazole and with a CE4 cyst at the start of pregnancy, reactivation of the cyst during pregnancy was observed. All pregnancies except three had eutocic delivery. Cesarean sections were performed for reasons unrelated to CE. In our experience, “watch and wait” in pregnant women with uncomplicated transitional and inactive CE of the liver was a safe option in a small cohort of patients. Pooled data from other referral centers, including cases with CE1 and CE2 cysts, are needed to confirm the safety of this approach.

This study evaluated four biomarkers of inflammation or fibrosis as progression indicators for heart disease in patients with Chagas disease. We compared values of these markers at the time of the first sample collection of blood (first time point) and at the time of the last collection of blood (second time point) for 103 individuals positive for Trypanosoma cruzi antibodies. They were split into two clinical groups: 52 individuals with the indeterminate form of the disease at the first time point and 51 controls that already had either cardiac involvement (N = 25) or megaviscera (megaesophagus and/or megacolon; N = 26) at that time. All individuals had an electrocardiogram performed both at the first and second time point (mean time between time points: 11 years). All samples were blind tested for galectin-3, brain natriuretic peptide (NT-proBNP), lysyl oxidase-like protein 2 (LOXL2), and troponin. Differences in concentrations between samples were analyzed using the months between samples as the covariate. This analysis showed that values for all markers, except troponin biomarker had a significative increase at the second time point for the 91 patients without progression. A similar result was obtained for NT-proBNP and LOXL2 with sera from 12 patients that progressed with cardiac disease. The single marker that showed a significative difference between groups (P = 0.01) was galectin-3. We concluded that galectin-3 was the only marker with a prognostic value in relation to the progression or worsening of heart disease in patients with Chagas disease.

Asymptomatic hepatitis C virus (HCV) infection without treatment is associated with chronic liver diseases including hepatocellular carcinoma. A major obstacle to hepatitis C diagnosis leading to antiviral treatment in some developing countries is the complicated HCV testing required before treatment. To simplify an HCV test-to-treat strategy, which could lead to timely diagnosis and treatment at the point-of-care, we evaluated the performance of four anti-HCV rapid diagnostic tests (RDTs) (Abon, Blue Cross, Healgen, and SD Bioline). They yielded comparable sensitivity (80–83%), specificity (99–100%), and accuracy (90–91.5%). When we field-tested Abon in 4,769 residents of an HCV-endemic province in Thailand, 306 seropositive individuals (6.4%) were identified. In comparison, laboratory test using an automated commercial chemiluminescent microparticle immunoassay (ARCHITECT anti-HCV assay, Abbott Diagnostics, Chicago, IL) identified slightly more seropositives (327/4,769 or 6.9%). Field implementation suggests that Abon was sensitive (88.7%), specific (99.6%), and accurate (98.9%). Furthermore, 82% (250/306) of Abon-positive samples had detectable HCV RNA as determined by nucleic acid test (cobas® 4800 HCV assay; Roche Diagnostics GmbH, Mannheim, Germany). The same 250 samples out of 327 reactive in Abbott immunoassay also had detectable HCV RNA (mean RNA level: log 6.28 IU/mL, range: log 3.06– 7.78 IU/mL). The use of RDT followed by qualitative nucleic acid test can cost-effectively identify the majority of HCV seropositive individuals with active infection, which will obviate the need for expensive viral load quantification tests when simplifying HCV diagnosis for the test-to-treat program at the point-of-care.

The objective of this cohort study was to examine the prevalence of acute respiratory illness among children under 5 years of age and to identify water, sanitation, and hygiene (WASH) and nutritional risk factors. This prospective cohort study was conducted in Walungu Territory, South Kivu, Democratic Republic of the Congo (DRC) and enrolled 512 participants. Spot checks of the household environment were conducted at baseline. Baseline minimum dietary diversity (MDD) was defined by consumption of five or more of the following food groups: 1) breast milk; 2) grains, roots, and tubers; 3) legumes and nuts; 4) dairy products; 5) flesh foods; 6) eggs; 7) vitamin A rich fruits and vegetables; and 8) other fruits and vegetables. Acute respiratory illness was defined as caregiver-reported rapid breathing, difficulty breathing, lower chest wall in-drawing, or coughing in the previous 2 weeks obtained at a 6-month follow-up. A total of 58% of children had acute respiratory illness, 19% had soap present in the household cooking area, and 4% in the defecation area, and 21% of children met MDD. A decreased odds of acute respiratory illness was associated with soap being present in the household cooking area (odds ratio [OR]: 0.49, 95% confidence interval [CI]: 0.38–0.88) and children with MDD (OR: 0.62, 95% CI: 0.38–1.00). These findings highlight the need for interventions targeting hygiene and improved dietary diversity among rural DRC households to reduce the rate of respiratory illnesses in children under 5 years.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging life-threatening infectious disease caused by the tickborne SFTS virus (SFTSV), first identified in China in 2009 and then in Japan in 2013. Human SFTS cases were reported to be concentrated in western Japan, but the epidemiological conditions of SFTSV infection in a specific region are still obscure. We performed an epidemiological study of SFTSV in Oita Prefecture on the island of Kyushu, located in western Japan. For our research, we collected sera from wild and domestic animals (deer, wild boars, raccoons, cats, and dogs) and ticks from January 2010 to November 2020 in Oita. The anti-SFTSV antibody positivity rate of deer in 2014 was significantly higher than that in 2011 (65% versus 27%, P < 0.001). The anti-SFTSV antibody positivity rates of deer, wild boars, raccoons, wild dogs, domestic dogs, and domestic cats were 55%, 12%, 27%, 1.8%, 0.53%, and 1.4%, respectively. Moreover, RT-PCR could not detect SFTSV in any tick sample. Of the six areas of Oita Prefecture, only the Eastern area showed no incidence or possibility of SFTSV infection among wild and domestic animals, ticks, and human beings. Further investigation is required to assess whether local seroepidemiology in animals will help assess the risk of SFTSV infections in inhabitants.

Tuberculosis (TB) remains one of the world’s leading infectious cause of morbidity and mortality. Positron emission tomography (PET) associated with computed tomography (CT) allows a structural and metabolic evaluation of TB lesions, being an excellent noninvasive alternative for understanding its pathogenesis. DOTATOC labeled with gallium-68 (68Ga-DOTATOC) can bind to somatostatin receptors present in activated macrophages and lymphocytes, cells with a fundamental role in TB pathogenesis. We describe 68Ga-DOTATOC uptake distribution and patterns in thoracic lymph nodes (LN) and pulmonary lesions (PL) in immunocompetent patients with active postprimary TB, analyze the relative LN/PL uptake, and compare this two tracer’s uptake. High uptake of both radiotracers in PL and LN was demonstrated, with higher LN/PL ratio on 68Ga-DOTATOC (P < 0.05). Considering that LN in immunocompetent patients are poorly studied, 68Ga-DOTATOC can contribute to the understanding of the complex immunopathogenesis of TB.

Schistosoma haematobium continues to pose a significant public health burden despite ongoing global control efforts. One of several barriers to sustained control (and ultimately elimination) is the lack of access to highly sensitive diagnostic or screening tools that are inexpensive, rapid, and can be utilized at the point of sample collection. Here, we report an automated point-of-care diagnostic based on mobile phone microscopy that rapidly images and identifies S. haematobium eggs in urine samples. Parasite eggs are filtered from urine within a specialized, inexpensive cartridge that is then automatically imaged by the mobile phone microscope (the “SchistoScope”). Parasite eggs are captured at a constriction point in the tapered cartridge for easy imaging, and the automated quantification of eggs is obtained upon analysis of the images by an algorithm. We demonstrate S. haematobium egg detection with greater than 90% sensitivity and specificity using this device compared to the field gold standard of conventional filtration and microscopy. With simple sample preparation and image analysis on a mobile phone, the SchistoScope combines the diagnostic performance of conventional microscopy with the analytic performance of an expert technician. This portable device has the potential to provide rapid and quantitative diagnosis of S. haematobium to advance ongoing control efforts.

The impact and disruption of infectious disease outbreaks stretch far beyond their direct death toll, as they often overburden health systems, reduce treatment seeking behaviors, and interrupt treatment regimens. This study examines the impact of the 2014–2016 Ebola virus outbreak on tuberculosis (TB) treatment outcomes at the 34 Military Hospital in Freetown, Sierra Leone. We used retrospective data from 1,085 TB patient outcome data registers to build a multinomial logistic regression model to evaluate the change in TB treatment outcomes before and after the Public Health Emergency of International Concern (PHEIC) declaration in August 2014. These results showed that HIV status, patient age, whether patients had active versus latent TB, and the time since the start of the outbreak were significantly associated with TB treatment outcomes. The model showed an increase in probability of unknown and unsuccessful (died or treatment failed) treatment outcomes with each month after the PHEIC declaration, across age groups, TB status, and HIV status.

Diarrhea is one of the leading causes of childhood illness and a major cause of infant and child mortality globally. In the Reducing Enteropathy, Undernutrition, and Contamination in the Environment (REDUCE) prospective cohort study, we investigated the association between diarrheal disease awareness and handwashing with soap among caregivers of children under 5 years of age. A total of 259 caregivers of children under 5 years of age in Walungu Territory, South Kivu, Democratic Republic of the Congo (DRC), were administered an open-ended questionnaire assessing awareness of diarrheal disease transmission and prevention, and key times to wash hands with soap. An overall diarrhea awareness score was developed based on the responses to these items. Five-hour structured observation of handwashing behaviors was conducted at the 6-month follow-up. Diarrheal disease awareness among caregivers was low. Only 32% of caregivers were able to correctly identify a method of diarrhea prevention. The median diarrhea awareness score was 3 out of 10 (SD: 1.7, range: 0–9). During structured observation, 9% of caregivers washed their hands with soap at a food-related event and 9% washed their hands with soap at a stool-related event. Higher diarrheal disease awareness was associated with an increased odds of handwashing with soap at food-related events (odds ratio: 1.40, 95% confidence interval: 1.03, 1.90). Our findings emphasize the need for targeted water, sanitation, and hygiene interventions to increase diarrhea awareness and facilitate handwashing with soap among caregivers of children under 5 years in rural DRC.

Crimean-Congo hemorrhagic fever (CCHF) is a highly fatal zoonotic disease endemic to Kazakhstan. Previous work estimated the seroprevalence of CCHF virus (CCHFV) among livestock owners in the Zhambyl region of southern Kazakhstan at 1.2%. To estimate CCHFV seroprevalence among cattle and sheep, we selected 15 villages with known history of CCHFV circulation (endemic) and 15 villages without known circulation (nonendemic) by cluster sampling with probability proportional to livestock population size. We collected whole blood samples from 521 sheep and 454 cattle from randomly selected households within each village and collected ticks found on the animals. We tested livestock blood for CCHFV-specific IgG antibodies by ELISA; ticks were screened for CCHFV RNA by real-time reverse transcription polymerase chain reaction and CCHFV antigen by antigen-capture ELISA. We administered questionnaires covering animal demographics and livestock herd characteristics to an adult in each selected household. Overall weighted seroprevalence was 5.7% (95% CI: 3.1, 10.3) among sheep and 22.5% (95% CI: 15.8, 31.2) among cattle. CCHFV-positive tick pools were found on two sheep (2.4%, 95% CI: 0.6, 9.5) and three cattle (3.8%, 95% CI: 1.2, 11.5); three CCHFV-positive tick pools were found in nonendemic villages. Endemic villages reported higher seroprevalence among sheep (15.5% versus 2.8%, P < 0.001) but not cattle (25.9% versus 20.1%, P = 0.42). Findings suggest that the current village classification scheme may not reflect the geographic distribution of CCHFV in Zhambyl and underscore that public health measures must address the risk of CCHF even in areas without a known history of circulation.

Eschar is used to establish the clinical diagnosis of scrub typhus. To identify the prevalence of eschar and its location in scrub typhus, we reviewed globally published peer-reviewed articles. We conducted a systematic literature review, using publications extracted from PubMed from January 1943 to August 31, 2019 with the keywords “scrub typhus” or “tsutsugamushi.” We collected articles associated with eschar prevalence and distribution in scrub typhus infection and reported on the body locations of eschar. A total of 458 articles containing information on the prevalence, geographical distribution, and body distribution of eschar were used for this review. The overall prevalence rate of eschar was 58.0% with the greatest prevalence in East Asia (78.7%) followed by Oceania (52.2%), Southeast Asia (41.4%), and then the lowest in South Asia (32.8%). The frequency of eschar distribution was highest in the inguinal area (28.5%), followed by the anterior area (28.0%), and the lower extremities (22.0%). The upper extremities (8.9%), back (6.6%), and head and neck (6.1%) regions had relatively low frequencies of distribution. We identified the prevalence of eschar differed by geographic locations and anatomical sites on the patient of scrub typhus.

Infection by Opisthorchis viverrini causes significant health problems, including cholangiocarcinoma (CCA); thus control and elimination of this trematode is an important strategy for the reduction of CCA. Currently, urine and copro antigen detection is more sensitive than parasitological examination of the feces for the diagnosis of opisthorchiasis. Given limitations in human studies, we used an animal model to quantify the parasite antigen profiles in urine and feces in O. viverrine–infected hamsters, and postdrug treatment. The positive detections of O. viverrini antigen began from week 1 in urine and week 2 in feces after infection until week 28 of the study. The recoveries of O. viverrini worms were detected starting from week 1 and eggs of O. viverrini were detected in feces from week 3 after infection and remained detectable throughout the study period. There was a significant positive correlation of urine and copro antigen levels with the number of fecal egg counts (P P P

The objective of our study was to assess the effect of human umbilical cord blood (HUCB) mesenchymal stem cells (MSCs) transplantation on schistosomal hepatic fibrosis in mice. The study animals were divided into three groups. Group I is a control group, where the mice were infected with Schistosoma mansoni cercariae and remained untreated. The mice of the other two groups were infected and treated with either praziquantel (Group II) or HUCB-MSCs (Group III). Liver function tests, as well as histopathological evaluation of liver fibrosis using hematoxylin and eosin and Masson's trichrome stains, were performed. Additionally, an immunohistochemical study was carried out using anti-glial fibrillary acidic protein (GFAP) in hepatic stellate cells. Compared to the control group, the treated (praziquantel and MSCs) groups showed a substantial improvement, with a significant difference regarding the histopathological evaluation of liver fibrosis in the MSCs-treated group. In conclusion, MSCs could be a promising and efficient cell therapy for liver fibrosis.

There is a need for better tools to monitor the transmission of lymphatic filariasis and malaria in areas undergoing interventions to interrupt transmission. Therefore, mosquito collection methods other than human landing catch (HLC) are needed. This study aimed to compare the Ifakara tent trap type C (ITTC) and the Biogents sentinel trap (BGST) to the HLC in areas with different vector densities. Mosquitoes were collected in two villages in Mali from July to December in 2011 and 2012. The three methods were implemented at each site with one ITTC, one BGST, and one HLC unit that consisted of one room with two collectors—one indoor and the other outdoor. The Anopheles collected in 2011 were individually dissected, whereas those from 2012 were screened in pools using reverse transcription-polymerase chain reaction (RT-PCR) to determine the maximum infection prevalence likelihood (MIPL) for Wuchereria bancrofti and Plasmodium falciparum. The dissection of the females also allowed to assess the parity rates, as well its results. Over the 2 years, the HLC method collected 1,019 Anopheles, yields that were 34- and 1.5-fold higher than those with the BGST and ITTC, respectively. None of the dissected Anopheles were infected. The RT-PCR results showed comparable MIPL between HLC and ITTC for W. bancrofti with one infected pool from each trap’s yield (respectively 0.03% [0.0009–0.2%] and 0.04% [0.001–0.2%]). For P. falciparum, no infected pool was recovered from BGST. The ITTC is a good alternative to HLC for xenomonitoring of program activities.

Dietary iron and folate are nutrients of great importance during pregnancy because of the role they play to ensure optimal birth outcomes. Dietary intake has been found to decline during the third trimester. This study sought to assess the dietary iron and folate intake in the third trimester and pregnancy outcomes of women in their third trimester attending antenatal clinics at Korle-Bu Teaching Hospital. Eighty-one participants at a gestational age of 32 weeks were recruited and monitored until delivery—from May 4, 2020 to July 1 2020—using a consecutive sampling method at the Department of Obstetrics and Gynecology, Korle-Bu Teaching Hospital. Dietary intake information was obtained based on a 52-item quantitative food frequency questionnaire. Daily supplement doses of participants were recorded. Serum concentrations of iron (ferritin) and folate were determined using ELISA microwells. The mean dietary intake of iron and folate was 13.5 ± 8.30 mg and 331.0 ± 114.0 μg, respectively. The mean intake of iron and folic acid supplements was 42.7 ± 48.8 mg and 5.5 ± 11.1 mg, respectively. Most of the participants had serum ferritin and folate levels in the normal range (82.7% and 87.7%, respectively). Almost all the participants had positive birth outcomes, and total dietary iron was a significant predictor of birth outcome (P = 0.041). The majority of pregnant women did not meet the daily recommendation for iron and folate, but adherence to daily supplement intake was good and could have accounted for the positive birth outcomes.

Repeated intravenous (IV) administration of radiation-attenuated sporozoite (RAS) vaccines induces Plasmodium-specific CD8+ liver-resident memory T (Trm) cells in mice and achieves sterile protection against challenge. Our heterologous “prime-and-trap” vaccine strategy was previously shown to simplify and improve upon RAS vaccination. Prime-and-trap vaccination combines epidermal priming by DNA-encoded circumsporozoite protein (CSP) antigen followed by a single IV dose of freshly dissected RAS (fresh-RAS) to direct and trap activated and expanding CD8+ T cells in the liver. Prime-and-trap vaccination protects mice against wild-type sporozoite (spz) challenge. Assessment of prime-and-trap vaccines in nonhuman primate (NHP) models and/or humans would be greatly enabled if fresh-RAS could be replaced by cryopreserved RAS (cryo-RAS). Here, we investigated if fresh-RAS could be replaced with cryo-RAS for prime-and-trap vaccination in BALB/cj mice. Despite a reduction in spz vaccine liver burden following cryo-RAS administration compared with fresh-RAS, cryo-RAS induced a similar level of Plasmodium yoelii (Py) CSP-specific CD8+ liver Trm cells and completely protected mice against Py spz challenge 112 days after vaccination. Additionally, when the glycolipid adjuvant 7DW8-5 was co-administered with cryo-RAS, 7DW8-5 permitted the dose of cryo-RAS to be reduced four-fold while still achieving high rates of sterile protection. In summary, cryo-RAS with and without 7DW8-5 were compatible with prime-and-trap malaria vaccination in a mouse model, which may accelerate the pathway for this vaccine strategy to move to NHPs and humans.

Acknowledgements: We thank the municipality of Jeddah, Saudi Arabia for supporting this research study and facilitating fieldwork and sampling operations which allowed us to have access and build wild mosquito colonies. We thank Nancy Endersby-Harshman for facilitating the import of mosquito populations into the quarantine insectary. We thank Meng-Jia Lau for advice on primers and Véronique Paris for assistance with colony maintenance. We thank Kim R Blasdell for providing lab assistance at ACDP. The authors acknowledge the capabilities of the Australian Centre for Disease Preparedness in undertaking this research, including infrastructure funded by the National Collaborative Research Infrastructure Strategy., Funder: CSIRO; Grant(s): WBS: R-91040-11, Aedes aegypti mosquitoes carrying self-spreading, virus-blocking Wolbachia bacteria are being deployed to suppress dengue transmission. However, there are challenges in applying this technology in extreme environments. We introduced two Wolbachia strains into Ae. aegypti from Saudi Arabia for a release program in the hot coastal city of Jeddah. Wolbachia reduced infection and dissemination of dengue virus (DENV2) in Saudi Arabian mosquitoes and showed complete maternal transmission and cytoplasmic incompatibility. Wolbachia reduced egg hatch under a range of environmental conditions, with the Wolbachia strains showing differential thermal stability. Wolbachia effects were similar across mosquito genetic backgrounds but we found evidence of local adaptation, with Saudi Arabian mosquitoes having lower egg viability but higher adult desiccation tolerance than Australian mosquitoes. Genetic background effects will influence Wolbachia invasion dynamics, reinforcing the need to use local genotypes for mosquito release programs, particularly in extreme environments like Jeddah. Our comprehensive characterization of Wolbachia strains provides a foundation for Wolbachia-based disease interventions in harsh climates.

SARS-CoV-2 has had a lasting effect on the overall health of recovered patients, called ‘long COVID’. Currently, there is a lack of a validated standard questionnaire to assess post-COVID health status. A retrospective observational study involving the recovered COVID patients admitted to a secondary care hospital in India between June to December 2020 (n = 123), was conducted using the EuroQol-5D-5L scale at discharge, 4 weeks and 8 weeks post-discharge. A significant difference in anxiety/depression scores was found (χ(2) = 65.6, p