Endemic Areas Research Articles

Clinical profile and thiamine transporter gene (SLC19A2 and SLC19A3) variations in infants with thiamine-responsive pulmonary hypertension and acute respiratory infection

Abstract Maternal thiamine deficiency is prevalent in low- and middle-income countries. Thiamine-responsive pulmonary hypertension (TRPHTN) in exclusively breastfed infants is reported in India. Thiamine transporter gene (ThTR) variations have not been studied. This study compared the presentation of exclusively breastfed infants with respiratory distress diagnosed as TRPHTN or acute respiratory infection (ARI). We investigated pathogenic variations in the SLC19A2 and SLC19A3 ThTr genes in a representative sample. Observational study. Tertiary care pediatric unit of a teaching hospital in southern India. Data collection was prospective. We included exclusively breastfed infants between 1 and 6 months of age with respiratory distress. Infants with PHTN in echocardiography and lactic acidosis (LA) received thiamine. TRPHTN was diagnosed based on response within 72 h. Infants with fever, chest findings, and positive microbiology were managed as ARI. The ThTr genes were sequenced and analyzed. Chi-square and stratified analysis were done to determine TRPHTN risk. Forty infants with TRPHTN and 42 with ARI were included. The median pulmonary arterial pressure in the TRPHTN group was 51.5 mmHg. Mild PHTN was seen in 65%, moderate in 22.5%, and severe in 12.5%. Cardiac failure (P < .001), stridor and aphonia (P < .001), encephalopathy (P = .024), LA (P < .001), and PHTN (P <.001) facilitated the diagnosis. The adjusted risk was 17.3 (95% confidence interval 7.8–38.3; P <.001). The ThTR sequencing showed wild-type genotypes. TRPHTN has a distinct, identifiable presentation. Lactate and pulmonary pressure estimations are useful investigations in thiamine deficiency endemic areas. We could not demonstrate a genetic variation that determines susceptibility.

BIOGEOGRAPHIC PATTERNS OF COLOMBIAN FROGS AND TOADS

Using the data provided in Ruiz-Carranza et al. (1996) the distributions of the 540 species of frogs and toads are partitioned among ten ecogeographic units of Colombia defined on the basis of precipitation and elevation. Sorne lowlands areas (Pacific lowlands, Amazonia) exhibit high diversity (85-94 species) but lowlands areas in general are impoverished (30-52 species), especially when contrasted with upland areas. The three Andean cordilleras harbor between 87 and 121 species of frogs and toads, demonstrating that the biodiversity of Colombia resides primarily in its montane components, not in its lowland rainforests. When biological endemicity is separated from political endemicity, five areas of high endemicity remain (the three Andean cordilleras, the Sierra Nevada de Santa Marta, and the Pacific lowlands). We endeavor to explain this description by recourse to cladistic analyses of several groups of leptodactylid frogs where we find that the general pattem of diversification is by meaos of horizontal diversification (allopatric speciation) with a minor contribution from vertical diversification.

Inactivated rabies-based Lassa fever virus vaccine candidate LASSARAB protects nonhuman primates from lethal disease

Lassa fever virus (LASV), a member of the Arenavirus family, is the etiological agent of Lassa fever, a severe hemorrhagic disease that causes considerable morbidity and mortality in the endemic areas of West Africa. LASV is a rodent-borne CDC Tier One biological threat agent and is on the World Health Organization’s (WHO) Priority Pathogen list. Currently, no FDA-licensed vaccines or specific therapeutics are available. Here, we describe the efficacy of a deactivated rabies virus (RABV)-based vaccine encoding the glycoprotein precursor (GPC) of LASV (LASSARAB). Nonhuman primates (NHPs) were administered a two-dose regimen of LASSARAB or an irrelevant RABV-based vaccine to serve as a negative control. NHPs immunized with LASSARAB developed strong humoral responses to LASV-GPC. Upon challenge, NHPs vaccinated with LASSARAB survived to the study endpoint, whereas NHPs in the control group did not. This study demonstrates that LASSARAB is a worthy candidate for continued development.

First detection of Leishmania major in dogs living in an endemic area of zoonotic cutaneous leishmaniasis in Tunisia

BackgroundDogs are considered the main domestic animals that may be a reservoir for Leishmania infantum, the agent of zoonotic visceral leishmaniasis (ZVL) in several countries of the world. The dog may host other Leishmania species, but its epidemiological role in the maintenance and spreading of these parasites is not completely elucidated. Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, affects thousands of people every year and is particularly diffused in many countries of North Africa and Middle East Asia. In ZCL endemic countries, few reports of L. major-positive dogs have been reported, probably because most human cases occur in poor rural areas where the social role of the dog and its medical management is not well considered. The aim of the present study is to better understand the possible involvement of domestic dogs in the epidemiology of ZCL.MethodsOur research focused on a well-established endemic focus of ZCL, in the area of Echrarda, Kairouan Governorate, central Tunisia. A total of 51 dogs with no or mild clinical signs of vector borne diseases were selected in small villages where human cases of ZCL are yearly present. All dogs were sampled for the Leishmania spp. diagnosis, by using the following procedures: blood sample for serology and buffy coat quantitative polymerase chain reaction (qPCR), popliteal fine needle aspiration, and cutaneous biopsy punch for lymph node and skin qPCR.ResultsThe results demonstrated a high percentage (21.6%) of dogs positive at least at one or more test; the most sensitive technique was the lymph node qPCR that detected 8/11 positive dogs. Nine, out of the eleven positive dogs, resulted as infected by Leishmania infantum; ITS1-PCR-sequencing allowed Leishmania major identification in the remaining two cases, both from the popliteal lymph node samples, which can suggest a possible visceral spread of a cutaneous Leishmania species in the dog. Interestingly, one of the two L. major-positive dogs was living in the same house where 6-year-old children showed cutaneous lesions referred to as ZCL.ConclusionsTo our knowledge, this is the first report of L. major-positive dogs in Tunisia, the epidemiological role of which remains under investigation.Graphical

Epidemiology and control of monkeypox outbreak in Houston, Texas

BackgroundIn the 2022–2023 global outbreak, the United States and state of Texas recorded a total of 31,277 and 3,085 confirmed monkeypox (Mpox) cases respectively as of November 2023. This study aims to investigate the demographic characteristics and risk factors of Mpox outbreak in Houston and document the epidemiologic control measures implemented with their outcomes. MethodsHouston Health Department received reports of suspected Mpox cases via electronic case reports and laboratory reports from healthcare providers within Houston. These were then investigated and reclassified as either positive or negative using DNA polymerase chain reaction tests. All the reported cases received between May 2022 and January 2023 were included in this study using convenient sampling methods. Descriptive statistics using frequency distribution was used to analyze the sociodemographic, clinical features and travel history of the cases. A two-sided Chi-squared test was used to determine association between Mpox test results and risk factors with significant level set at P < 0.05. Other infection control measures such as community engagement, health education, tracking and contact tracing, vaccination, referrals and laboratory sample logistics support were implemented by the health department. ResultsOut of the total of 1,625 suspected persons investigated for Mpox, 724 (44.6%) tested positive. Among the 724 confirmed cases, male was 700 (96.7%), females 20 (2.8%), transgender male 1 (0.1%), transgender female 3 (0.4%). Age groups 30–39 years constituted 43.6%, 18–29 years 27.4%, 40–49 years 18.2%, 50–59 years was 8%. Race distribution of positive cases was Whites 43.4%, African American 38.7%, Asian 1.4%. Risk factors with P < 0.05 included male gender, age groups 30–39 years and 40–49 years, travel history to Mpox endemic areas, recent sexual contact with known or suspected Mpox cases, human immunodeficiency virus seropositivity. Identifying as gay and bisexual were also statistically significant risk factors for Mpox infection. ConclusionThe timely implementation of primary and secondary prevention measures targeted at the most at-risk populations was very effective at curtailing the spread of Mpox infection within the city of Houston.

Tick-borne encephalitis vaccine breakthrough infections induce aberrant T cell and antibody responses to non-structural proteins

Tick-borne encephalitis virus (TBEV) vaccine breakthrough (VBT) infections are not uncommon in endemic areas. The clinical and immunological outcomes have been poorly investigated. We assessed the magnitude and specificity of virus-specific antibody and T cell responses after TBE in previously vaccinated subjects and compared the results with those of unvaccinated TBE patients and study subjects that received vaccination without VBT infection. Symptomatic TBEV infection of unvaccinated study subjects induced virus-specific antibody responses to the E protein and non-structural protein 1 (NS1) as well as T cell responses to structural and other non-structural (NS) proteins. After VBT infections, significantly impaired NS1-specific antibody responses were observed, while the virus-specific T cell responses to the NS proteins were relatively strong. VBT infection caused predominantly moderate to severe disease during hospitalization. The level of TBEV EDIII- and NS1-specific antibodies in unvaccinated convalescent patients inversely correlated with TBE severity and neurological symptoms early after infection.

Thrombocytopenia in Plasmodium vivax Malaria: A Report from a Sub-zonal Hospital in Western Rajasthan

Abstract Background: Malaria continues to be a major public health problem in India. Vivax malaria is being increasingly seen with thrombocytopenia. The reported prevalence of the same has been extremely variable and its significance is not well established. This study was conducted to ascertain the prevalence and severity of thrombocytopenia in vivax malaria and assess the outcome of cases with severe thrombocytopenia. A secondary objective was to compare the clinical and laboratory profile of cases of vivax malaria with falciparum malaria and mixed infection. Materials and Methods: This hospital-based prospective study was carried out in the department of general medicine at a sub-zonal hospital in Western Rajasthan in the year 2022. Consecutive febrile patients with a diagnosis of malaria were included in the study after ruling out coexistent alternate infections. Results: A total of 396 cases were enrolled. Ninety-nine percent of patients were male. The mean age of the study group was 32.1 years. A total of 328 (90.8%) out of 361 vivax malaria cases had thrombocytopenia (platelet count &lt;150 × 103 μL) with 26.5% having severe thrombocytopenia (platelet count &lt;50 × 103 μL). The mean defervescence duration was 44.4 h in vivax malaria. 3.4% of severe vivax malaria cases required intensive care unit care due to hypotension, respiratory distress, and multiorgan dysfunction, and none of them had any bleeding manifestations. All cases recovered well after standard treatment. There was a significant statistical difference between the mean platelet count among the three types of malaria: vivax, falciparum, and mixed (vivax + falciparum infections) (P = 0.03). Similarly, on applying Chi-square test, there was a significant difference in severe thrombocytopenia across the groups (P = 0.01). Conclusion: There is a high prevalence of thrombocytopenia in vivax malaria including severe thrombocytopenia. In the majority of cases, this thrombocytopenia does not result in any adverse event, and cases respond well to conventional treatment. Clinicians need to be aware of the extent and severity of thrombocytopenia in vivax malaria and rule out this treatable condition in endemic areas with a high prevalence of other coexistent infections causing thrombocytopenia.

Improving Clinician Awareness of and Screening for Chagas Disease with an Educational Intervention.

Chagas disease is an underrecognized, chronic, and potentially life-threatening disease caused by the parasite Trypanosoma cruzi. We aimed to improve awareness and screening for Chagas disease among patients from endemic areas using a large safety-net academic hospital system in the United States. We developed an educational intervention consisting of a case-based didactic session presented to physicians, trainees, and other healthcare providers at conferences across different departments. Performance on a knowledge assessment administered before and after the presentation was analyzed with paired Student's t-test for within-subject difference testing. Institutional testing rates for T. cruzi were evaluated for an equal time period (29 months) before and after the start of the intervention. Testing rates were compared by a Welch's unequal variances t-test and by interrupted time series based on multivariate linear regression. Eleven educational sessions were held over the intervention period, and 103 participants completed the pre- and post-presentation surveys. The mean survey scores were 59.2% before the presentation and 96.6% after presentation (P <0.001). Trypanosoma cruzi testing during the postintervention period was significantly higher than testing during the pre-intervention period (171 patients pre-intervention versus 378 patients postintervention [P = 0.015]). Notable increases in testing from the pre-intervention to postintervention periods occurred among midwives (1-68 patients tested) and trainees (57-133 patients tested). Overall, 56/537 (10.4%) nonduplicate T. cruzi commercial screening tests were positive. Testing increased over time, both at an institutional level and within targeted departments. In addition to the educational program, other factors likely influenced expanded testing.

Electrocardiogram Abnormalities in Children With Lyme Arthritis.

Classically, Lyme disease follows a staged illness pattern with carditis occurring in early disseminated disease and arthritis in late-stage disease. A more comprehensive understanding of Lyme suggests that clinical stages may intersect. Little is known regarding the overlap of electrocardiogram (ECG) abnormalities in children with Lyme arthritis. This study aimed to estimate the prevalence of ECG changes in pediatric patients presenting with Lyme arthritis. In this retrospective, cross-sectional study was conducted at a tertiary care children's hospital in a Lyme endemic area; patients were identified based on Lyme testing performed from January 2012 to August 2022. Children diagnosed with Lyme arthritis by 2-tiered serology with ECGs obtained within 2 days of antibiotic initiation were included. A study cardiologist reviewed all ECGs for evidence of carditis defined as atrioventricular block, ST-T wave changes, QTc interval prolongation, accelerated junctional rhythm or right bundle branch block. Two hundred thirty-three patients were diagnosed with Lyme arthritis; 90 (38.6%) had ECGs completed. Five patients (5.6%) had ECG abnormalities: 3 were diagnosed with first-degree atrioventricular block, 1 with QTc prolongation, and 1 with ST-T wave changes. No clinical or laboratory features in patients with Lyme arthritis were associated with an increased likelihood of having an abnormal ECG. All patients with ECG abnormalities were treated with oral antibiotics, and none had clinically significant cardiac disease. ECG abnormalities in children with Lyme arthritis rarely occur and, when present, are not reflective of clinically significant cardiac disease. These results do not support routine screening ECGs on asymptomatic pediatric patients with Lyme arthritis.

Knowledge of Crimean-Congo Hemorrhagic Fever among Nurses at Al-Nasiriyah City Hospitals in Iraq

Background: CCHF caused by a tick-borne virus from the Bunyaviridae family, is a severe viral hemorrhagic fever with a mortality rate of 10–40%. Specific Background: Despite their critical role in treating and preventing CCHF, comprehensive research on CCHF transmission and knowledge among healthcare workers, especially nurses in Al-Nasiriyah, Iraq, is lacking. Knowledge Gap: Current literature lacks detailed studies on the awareness and preparedness of nurses regarding CCHF in high-risk areas. Aims: Aims to assess the knowledge of nurses concerning CCHF in Al-Nasiriyah’s educational hospitals and identify gaps in their understanding to improve disease management and prevention strategies. Results: Utilizing a descriptive cross-sectional design, the study surveyed 500 nurses across five teaching hospitals. The average age of participants was 28.83 years, with a predominant proportion holding diplomas and obtaining information primarily from social media. The results revealed that nurses' knowledge about CCHF was suboptimal, with 69.4% of correct answers and a predominance of moderate knowledge levels. Novelty: This research provides novel insights into the knowledge deficits among nurses in an endemic region, highlighting the critical need for targeted educational interventions. Implications: The findings underscore the necessity for comprehensive educational courses on occupational safety and disease prevention tailored to healthcare workers in endemic areas, aiming to enhance their knowledge and preparedness against CCHF. Highlights: Knowledge Gaps: Nurses’ CCHF understanding is inadequate. Educational Need: Targeted training can improve disease management. Information Sources: Social media use highlights need for reliable sources. Keywords: Crimean-Congo hemorrhagic fever, nurses' knowledge, endemic regions, healthcare education, CCHF prevention

Combating coal-burning-borne endemic arsenism in Shaanxi Province, Northwest China: The impact of high-arsenic coal ban, improved cook-stoves, and health education

To eliminate the epidemic of coal-burning-borne endemic arsenism (CBBA), our study organized and implemented comprehensive measures including high-arsenic coal ban, improved cook-stoves, and health education. We also aimed to promote the application value of these measures in preventing and controlling CBBA to the world. From 2004 to 2005, through a stratified random sampling method, we selected 58,256 individuals to investigate the prevalence of CBBA and the arsenic levels in 1287 environmental and biological specimens. The prevalence of CBBA was 19.26 % and significantly associated with the arsenic levels in coal, pepper, corn and hair, which were at or exceeded national upper limits. To timely prevent and control the disease, the comprehensive measures have been implemented since 2005 to present. Comparison and correlation analyses were utilized to evaluate the effectiveness of these measures in reducing the prevalence of CBBA. According to statistics, 73 high-arsenic coal mines were banned and over 99 % households in endemic areas accepted stove improvements and diversified health education. Monitoring studies during 2010–2019 has confirmed that these measures led to a decrease in urine arsenic levels among endemic residents, and they developed novel dietary practices, such as properly drying, storage, and washing of food. Additionally, the awareness rate of CBBA increased from less than 70 % to over 95 %. Finally, the prevalence of CBBA has decreased to 0.153 % investigated by a census involving 2.076 million endemic residents in 2019. In summary, CBBA in northwest China has been successfully controlled through banning on high-arsenic coal, introducing improved cook-stoves, and providing health education.

Determinants of immune responses predictive of protection against shigellosis in an endemic zone: a systems analysis of antibody profiles and function

Shigella is the third leading global cause of moderate or severe diarrhoea among children younger than 5years globally, and is the leading cause in children aged 24-59months. The mechanism of protection against Shigella infection and disease in endemic areas is uncertain. We aimed to compare the Shigella-specific antibody responses in individuals living in Shigella-endemic and non-endemic areas, and to identify correlates of protection in a Shigella-endemic location. We applied a systems approach to retrospectively analyse serological responses to Shigella across endemic and non-endemic populations. We profiled serum samples collected from 44individuals from the USA without previous exposure to Shigella and who were experimentally challenged with Shigella sonnei (non-endemic setting), and serum samples collected from 55Peruvian army recruits (endemic setting). In the endemic setting, a subset of 37samples collected from individuals infected with culture-confirmed Shigella flexneri 2a were divided into twogroups: susceptible, which included individuals infected within 90days of entering the camp (n=29); or resistant, which included individuals infected later than 90days after entering the camp (n=8). We analysed Shigella-specific antibody isotype, subclass, and Fc receptor binding profiles across IpaB, IpaC, IpaD, and lipopolysaccharide from Sflexneri 2a, 3a, and 6, and Ssonnei, and O-specific polysaccharide (OSP) from Sflexneri 2a and 3a and Ssonnei. We also evaluated antibody-mediated complement deposition and innate immune cell activation. The main outcome of interest was the detection of antibody markers and functionality associated with protection against shigellosis in a high-burden endemic setting. Adults with endemic exposure to Shigella possessed broad and functional antibody responses across polysaccharide, glycolipid, and protein antigens compared with individuals from non-endemic regions. In a setting with high Shigella burden, elevated levels of OSP-specific Fcα receptor (FcαR) binding antibodies were associated with resistance to shigellosis, whereas total OSP-specific IgA was not, suggesting a potentially unique functionality. OSP-specific FcαR binding IgA found in resistant individuals activated bactericidal neutrophil functions including phagocytosis, degranulation, and production of reactive oxygen species. Moreover, IgA depletion from resistant serum significantly reduced binding of OSP-specific antibodies to FcαR and antibody-mediated activation of neutrophils and monocytes. Our findings suggest that OSP-specific functional IgA responses contribute to protective immunity against Shigella infection in a high-burden setting. These findings will assist in the development and evaluation of Shigella vaccines. US National Institutes of Health.

Educational WhatsApp-delivered intervention based on social cognitive theory to promote leishmaniosis preventive behavior of health ambassadors: a randomized controlled trial

BackgroundMultidimensional strategies can promote preventive behaviors to prevent cutaneous leishmaniosis. WhatsApp, the popular messenger of Iranians, can be used as a platform to provide health education interventions. This study aimed to investigate the effect of using an educational intervention in WhatsApp based on social cognitive theory (SCT) on the preventive behaviors of health ambassadors.MethodsA randomized clinical trial was conducted from September 2020 to April 2021 on 220 people living in endemic areas of leishmaniosis in Mashhad Province, Iran. By the cluster method sampling, the samples were randomly divided into two intervention and control groups. The intervention was performed for the intervention group over two weeks. Data were collected using a researcher-made questionnaire based on the constructs of SCT before and after the intervention. SPSS 16 was implemented to test multiple statistical analyses.ResultsFindings from the intervention group compared with the control group showed that the scores of SCT constructs and preventive behaviors were significantly changed (P < 0.001) across time during baseline through follow-up. These changes were not significant in the control group.ConclusionsThe educational intervention based on the SCT model to promote leishmaniosis preventive behaviors is effective. This intervention module can be tested in other targeted populations in endemic areas to prevent and control leishmaniosis.Trial registrationIranian Registry of Clinical Trials Registry IRCT20200615047784N1, registered 02/09/2020.

Description of BCG and Tuberculosis Disease in a Cohort of 79 Patients with Chronic Granulomatous Disease.

Chronic granulomatous disease (CGD) is an inherited immunodeficiency caused by pathogenic variants of genes encoding the enzyme complex NADPH oxidase. In countries where tuberculosis (TB) is endemic and the Bacillus Calmette-Guérin (BCG) vaccine is routinely administered, mycobacteria are major disease-causing pathogens in CGD. However, information on the clinical evolution and treatment of mycobacterial diseases in patients with CGD is limited. The present study describes the adverse reactions to BCG and TB in Mexican patients with CGD. Patients with CGD who were evaluated at the Immunodeficiency Laboratory of the National Institute of Pediatrics between 2013 and 2024 were included. Medical records were reviewed to determine the clinical course and treatment of adverse reactions to BCG and TB disease. A total of 79 patients with CGD were included in this study. Adverse reactions to BCG were reported in 55 (72%) of 76 patients who received the vaccine. Tuberculosis was diagnosed in 19 (24%) patients. Relapse was documented in three (10%) of 31 patients with BGC-osis and six (32%) of 19 patients with TB, despite antituberculosis treatment. There was no difference in the frequency of BCG and TB disease between patients with pathogenic variants of the X-linked CYBB gene versus recessive variants. This report highlights the importance of considering TB in endemic areas and BCG complications in children with CGD to enable appropriate diagnostic and therapeutic approaches to improve prognosis and reduce the risk of relapse.

Vaccine Platform Comparison: Protective Efficacy against Lethal Marburg Virus Challenge in the Hamster Model.

Marburg virus (MARV), a filovirus, was first identified in 1967 in Marburg, Germany, and Belgrade, former Yugoslavia. Since then, MARV has caused sporadic outbreaks of human disease with high case fatality rates in parts of Africa, with the largest outbreak occurring in 2004/05 in Angola. From 2021 to 2023, MARV outbreaks occurred in Guinea, Ghana, New Guinea, and Tanzania, emphasizing the expansion of its endemic area into new geographical regions. There are currently no approved vaccines or therapeutics targeting MARV, but several vaccine candidates have shown promise in preclinical studies. We compared three vaccine platforms simultaneously by vaccinating hamsters with either a single dose of an adenovirus-based (ChAdOx-1 MARV) vaccine, an alphavirus replicon-based RNA (LION-MARV) vaccine, or a recombinant vesicular stomatitis virus-based (VSV-MARV) vaccine, all expressing the MARV glycoprotein as the antigen. Lethal challenge with hamster-adapted MARV 4 weeks after vaccination resulted in uniform protection of the VSV-MARV and LION-MARV groups and 83% of the ChAdOx-1 MARV group. Assessment of the antigen-specific humoral response and its functionality revealed vaccine-platform-dependent differences, particularly in the Fc effector functions.

Infection and biogeographical characteristics of Paragonimus westermani and P. skrjabini in humans and animal hosts in China: A systematic review and meta-analysis.

Paragonimiasis, primarily caused by Paragonimus westermani and P. skrjabini in China, is a common food-borne parasitic zoonosis. However, the national distribution of Paragonimus spp. infection and its associated environmental determinants remain poorly understood. In this paper, we summarize the infection of P. westermani and P. skrjabini and describe key biogeographical characteristics of the endemic areas in China. Data on Paragonimus infection in humans and animal hosts were extracted from eight electronic databases, including CNKI, CWFD, Chongqing VIP, SinoMed, Medline, Embase, PubMed, and Web of Science. A random-effects meta-analysis model was used to estimate the pooled prevalence. All survey locations were georeferenced and plotted on China map, and scatter plots were used to illustrate the biogeographical characteristics of regions reporting Paragonimus infection. A total of 28,948 cases of human paragonimiasis have been documented, with 2,401 cases reported after 2010. Among the 11,443 cases with reported ages, 88.05% were children or adolescents. The pooled prevalence of P. skrjabini is 0.45% (95% CI: 0.27-0.66%) in snails, 31.10% (95% CI: 24.77-37.80%) in the second intermediate host, and 20.31% (95% CI: 9.69-33.38%) in animal reservoirs. For P. westermani, the pooled prevalence is 0.06% (95% CI: 0.01-0.13%) in snails, 52.07% (95% CI: 43.56-60.52%) in the second intermediate host, and 21.40% (95% CI: 7.82-38.99%) in animal reservoirs. Paragonimus are primarily distributed in regions with low altitude, high temperature, and high precipitation. In northeastern China, only P. westermani infections have been documented, while in more southern areas, infections of both P. westermani and P. skrjabini have been reported. Paragonimiasis remains prevalent in China, particularly among children and adolescents. Variations exist in the intermediate hosts and geographical distribution of P. westermani and P. skrjabini. Additionally, altitude, temperature, and precipitation may influence the distribution of Paragonimus.

Babesiosis in immunosuppressed hosts: pathogenesis, diagnosis and management.

This review provides the most recent evidence of the challenges that occur in the management of babesiosis in immunocompromised hosts. The epidemiology of babesiosis is affected by climate change leading to increasing numbers of cases as well as increasing areas of endemicity. Immunosuppressed hosts, especially with asplenia or B-cell defects, are at high risk of having severe disease as well as persistent and relapsed infection. Resistance to the primary therapies azithromycin and atovaquone can develop leading to further challenges in treating persistent or relapsed disease in the immunocompromised host. Babesiosis is likely to become a more frequent infectious complication in immunosuppressed hosts as the areas of endemicity expand. Reduced efficacy of standard therapies is likely to continue emerging so more effort needs to be placed on methods of assessing resistance in vitro and developing more reliable treatments for resistant infections.

Measurement of cervical grainy sandy patches, homogeneous yellow sandy patches, and abnormal blood vessels proportions in women with female genital schistosomiasis - a clinical validation study of a digital gridded imaging technique

BackgroundFemale genital schistosomiasis (FGS) is characterised by cervico-vaginal lesions such as grainy sandy patches, homogeneous yellow sandy patches, and abnormal blood vessels. Diagnosis, treatment, and surveillance of FGS presents challenges due to the absence of diagnostic tools in endemic areas. Likewise, a tool for quantification of the lesions is missing. This study aimed to validate the digital gridded imaging technique (DGIT) for quantification of three specific cervical lesion types associated with FGS.MethodsUsing the QubiFier software program, 70 cervical photographic images obtained from women diagnosed with FGS and treated with Praziquantel (PZQ) were randomly sampled for a validation study. The women lived in a S. haematobium-endemic area of Madagascar. For each image, a semi-transparent grid was applied, composed of 424 equally sized squares positioned to cover the cervix. Squares exhibiting any of the specific lesions were marked by three observers to determine the grainy sandy patches proportion (GSP), homogeneous yellow sandy patches proportion (HSP), and abnormal blood vessel proportion (BVP). To train the observers, a set of ten images was utilized, leaving 60 images for the validation. To test inter-rater reliability, the 60 cervical images were scored independently by three observers. To test intra-rater reliability, ten images were scored twice with a two-week interval. Intraclass correlation coefficient (ICC) was used as the main statistical method to assess the reliability between observers.ResultsThe median age of the included women was 26.5 (IQR 20.8-33.0) years, and 74% of them had detectable S. haematobium eggs in their urine. The three proportions were found to be consistent and reliable across the observers, as well as the rescoring on Days 0 and 14. Inter-rater reliability was good for all three cervical lesion types (ICC 0.768-0.890). Intra-rater reliability was good for GSP (ICC 0.832) and excellent for HSP and BVP (ICC 0.932 and 0.982, respectively).ConclusionIn this study DGIT was validated as a potential morbidity detection method for quantification of the three lesion types associated with FGS.

Strategic use of 4 % deltamethrin impregnated-collar in seropositive dogs reduces the incidence of seroreactivity to visceral leishmaniasis in dogs from endemic areas

The effectiveness of a visceral leishmaniasis (VL) control strategy based on the application of 4 % deltamethrin impregnated collars (DIC) exclusively in seropositive dogs was assessed between 2018 and 2019, through a prospective study. The effectiveness of DIC-collaring was evaluated by comparing the incidence rate of anti-leishmanial antibodies among dogs from two endemic districts in Brazil. In one of the areas, the conventional control measure which is based on the non-compulsory euthanasia of LV seropositive dogs, was practiced by the official healthy service as a regular procedure, whereas strategic collaring, conceived in this study, was carried out in the other. Results of serological tests applied to serum samples collected from all domiciled dogs were evaluated in three consecutive times, spaced by around 200 days. Incidence rates of VL seroreactivity were compared between districts in the same period of time as well as within the same district, in consecutive periods. Based on the results, the risk of infection in the population under conventional control measure was up to four times higher than the risk of infection where DIC-collaring was used. The strategic use of collar proposed here emerged as a promising measure for VL control in dogs from endemic areas. Strategic collaring does not rely on the euthanasia of infected animals, an extremely controversial procedure, and instead of being used in all dogs, as collaring is normally recommended; only seropositive dogs are intervened. Strategic use of DIC has the potential to drastically reduce costs, if compared to mass collaring canine population.

The use of rapid diagnostic tests for chronic Chagas disease: An expert meeting report.

Chagas disease, caused by Trypanosoma cruzi, affects millions of people globally and is associated with significant underdiagnosis and undertreatment. Current diagnostic algorithms face challenges in remote regions. We aimed to review the potential of rapid diagnostic tests (RDTs) for screening or diagnosing chronic Chagas disease in endemic areas. An expert panel representing scientific and academic institutions from the Americas convened with the aim of discussing the use of RDTs. The study employed the nominal group technique, gathering insights from diverse experts during a 3-day meeting. Panel discussions covered RDT application, research protocols, and regulatory mechanisms. The results indicate that RDTs play a crucial role in surveillance and screening, although limitations in sensitivity and specificity exist. The expert group recommends standardized protocols, emphasizes the importance of cost-effectiveness assessments, and highlights the need to consider geographic validation. Despite these challenges, RDTs present a promising avenue for improving Chagas disease diagnosis in resource-limited settings. Future research and a collaborative approach are deemed essential for effective implementation.