Molecular Epidemiology of Western Equine Encephalitis Virus, South America, 2023-2024.

Western equine encephalitis virus (WEEV) is a mosquitoborne virus that reemerged in December 2023 in Argentina and Uruguay, causing a major outbreak. We investigated the outbreak using epidemiologic, entomological, and genomic analyses, focusing on WEEV circulation near the Argentina‒Uruguay border in Rio Grande do Sul state, Brazil. During November 2023‒April 2024, the outbreak in Argentina and Uruguay resulted in 217 human cases, 12 of which were fatal, and 2,548 equine cases. We determined cases on the basis of laboratory and clinical epidemiologic criteria. We characterized 3 fatal equine cases caused by a novel WEEV lineage identified through a nearly complete coding sequence analysis, which we propose as lineage C. Our findings highlight the importance of continued surveillance and equine vaccination to control future WEEV outbreaks in South America.

Infectious and non-infectious causes for pregnancy loss in South American camelids - A review.

South American camelids (SAC) are gaining popularity for various purposes, including fiber production, trekking, and companionship. High abortion rates pose a significant health issue in SAC herds, leading to substantial economic losses for breeders. Often, the causes of these abortions remain unidentified. This review provides a comprehensive summary of the known infectious and non-infectious causes of abortions in SAC.

Orthohantavirus infections in South America: a systematic review and meta-analysis.

Orthohantaviruses are zoonotic pathogens that cause acute and severe syndromes in humans. This review was performed to estimate the occurrence of human orthohantaviruses in South America between 2010 and 2022. A careful evaluation of the eligibility and quality of the articles was carried out after a systematic bibliographic search of four databases. The pooled frequency of human orthohantaviruses was calculated using a random effects model meta-analysis. The heterogeneity of estimates (resulting from the chi2 test and I2 statistics) was investigated by subgroup analysis and meta-regression. 1,962 confirmed cases of orthohantavirus infections were diagnosed among 35,548 individuals from seven South American countries. The general occurrence of orthohantaviruses was estimated to be 4.4% (95% confidence interval: 2.9-6.2%) based on general pooling of human cases from 32 studies. In a subgroup analysis considering the study design and method of diagnosis, the percentages of diagnosed orthohantavirus infections differed substantially (I2 = 97.8%, p = 0.00) among South American countries. Four genetic variants of orthohantavirus have been identified circulating in Argentina, Brazil, Bolivia, Chile, Colombia, and Peru. Although laboratory diagnosis of orthohantaviruses is not performed in many countries in South America, there is evidence that four different orthohantaviruses are circulating in the region. The pooled occurrence of viral infection was approximately 4.0% in more than half of the South American countries. Updated information on the occurrence of human infections is essential for monitoring the territorial spread and determining the frequency of this zoonosis.

Comparative genomics of canine parvovirus in South America: Diversification patterns in local populations.

Canine parvovirus (CPV) is a significant pathogen in domestic dogs worldwide, causing a severe and often fatal disease. CPV comprises three antigenic variants (2a, 2b, and 2c) distributed unevenly among several phylogenetic groups. The present study compared genetic variability and evolutionary patterns in South American CPV populations. We collected samples from puppies suspected of CPV infection in the neighboring Argentina and Uruguay. Antigenic variants were preliminarily characterized using PCR-RFLP and partial vp2 sequencing. Samples collected in Argentina during 2008-2018 were mainly of the 2c variant. In the Uruguayan strains (2012-2019), the 2a variant wholly replaced the 2c from 2014. Full-length coding genome and vp2 sequences were compared with global strains. The 2c and 2a strains fell by phylogenetic analysis into two phylogroups (Europe I and Asia I). The 2c strains from Argentina and Uruguay clustered in the Europe I group, with strains from America, Europe, Asia, and Oceania. Europe I is widely distributed in South America in the dog population and is also being detected in the wildlife population. The 2a strains from Uruguay formed the distinct Asia I group with strains from Asia, Africa, America, and Oceania. This Asia I group is increasing its distribution in South America and worldwide. Our research reveals high genetic variability in adjacent synchronic samples and different evolutionary patterns in South American CPV. We also highlight the importance of ancestral migrations and local diversification in the evolution of global CPV strains.

Predicting the potential distribution and coexistence of Chagas disease vectors in the Americas.

Predicting the potential distribution and coexistence of suitable geographic areas for Chagas disease vectors in the Americas is a crucial task for understanding the eco-epidemiological dynamics of this disease. The potential distribution and coexistence of 3 species-Rhodnius prolixus (Hemiptera: Reduviidae), Cavernicola pilosa (Hemiptera: Reduviidae), and Rhodnius pictipes (Hemiptera: Reduviidae) were modeled. Presence records were obtained and environmental variables were selected based on correlation analysis, Jackknife analysis and knowledge of the biology and natural history of the species. The MaxEnt algorithm included in the kuenm package of R software was used for modeling the potential distribution, and various scenarios of the BAM diagram (Biotic, Abiotic, and Movement variables) were evaluated. The variables contributing to the final models were different for each species. Rhodnius pictipes showed a potential distribution in South America, particularly in Brazil, Bolivia, Peru, Colombia, Venezuela, Guyana, and Suriname. Areas with environmentally suitable conditions for R. prolixus were located in southern Brazil, Peru, Colombia, southern Mexico, Guatemala, El Salvador, and Honduras, whereas for C. pilosa they were in southeastern Brazil, southeastern Central America, Peru, Ecuador, Colombia, Venezuela, Guyana, Suriname, and French Guiana. Co-occurrence analysis revealed distinct patterns in the neotropical region, with some areas indicating the potential distribution of 1 or more species. In Brazil, occurrence and co-occurrence areas were concentrated in the northwest and southeast regions. Overall, this study provides valuable information on the potential distribution and coexistence of vectors, which can inform targeted vector control strategies and contribute to global efforts in combating Chagas disease.

Emerging Challenges of Mpox Transmission: An In-depth Scoping Review and Evidence Mapping on Breastfeeding Practices in South America.

BACKGROUND: In 2022, a marked escalation in Monkeypox (Mpox) cases was observed in nonendemic regions, notably South America, despite the virus being traditionally endemic to Central and West Africa. This unexpected shift necessitated a deeper exploration of the novel transmission dynamics, including breastfeeding, given the emerging evidence of potential horizontal and vertical Mpox transmission during mother-infant interactions. RESEARCH AIM: The study aimed to critically evaluate existing evidence on potential horizontal and vertical Mpox transmission related to breastfeeding and to assess guidelines in South American countries regarding Mpox prevention during breastfeeding. METHODS: A scoping review and evidence mapping were conducted, adhering to the PRISMA Extension for Scoping Reviews (PRISMA-ScR) guideline. Data extraction involved identifying primary studies evaluating breastfeeding as a transmission route. Additionally, official documents from South American Health Ministries detailing guidelines or policies on breastfeeding in the context of maternal Mpox infection were reviewed. RESULTS: Three of 215 studies were found relevant; 2 were case reports, and 1 was a laboratory study. Available evidence suggests that contamination could likely occur horizontally through skin-to-skin contact. Six South American countries had issued guidelines on breastfeeding during Mpox infection, but the guidance varied and was not consistent across the region. CONCLUSIONS: The study emphasizes the need for clear and consistent guidelines on breastfeeding during Mpox outbreaks, particularly in South America. Collaborative strategies and regular research updates will be essential in addressing the ongoing public health challenge.

Little-known virus is on the rise in South America.

Deforestation and climate change may be helping Oropouche virus spread far beyond the Amazon Basin.

The every woman study™ low- and middle-income countries edition protocol: A multi-country observational study to assess opportunities and challenges to improving survival and quality of life for women with ovarian cancer.

BACKGROUND: Ovarian cancer is a challenging disease to diagnose and treat effectively with five-year survival rates below 50%. Previous patient experience research in high-income countries highlighted common challenges and opportunities to improve survival and quality of life for women affected by ovarian cancer. However, no comparable data exist for low-and middle-income countries, where 70% of women with the disease live. This study aims to address this evidence gap. METHODS: This is an observational multi-country study set in low- and middle-income countries. We aim to recruit over 2000 women diagnosed with ovarian cancer across multiple hospitals in 24 countries in Asia, Africa and South America. Country sample sizes have been calculated (n = 70-96 participants /country), taking account of varying national five-year disease prevalence rates. Women within five years of their diagnosis, who are in contact with participating hospitals, are invited to take part in the study. A questionnaire has been adapted from a tool previously used in high-income countries. It comprises 57 multiple choice and two open-ended questions designed to collect information on demographics, women's knowledge of ovarian cancer, route to diagnosis, access to treatments, surgery and genetic testing, support needs, the impact of the disease on women and their families, and their priorities for action. The questionnaire has been designed in English, translated into local languages and tested according to local ethics requirements. Questionnaires will be administered by a trained member of the clinical team. CONCLUSION: This study will inform further research, advocacy, and action in low- and middle-income countries based on tailored approaches to the national, regional and global challenges and opportunities. In addition, participating countries can choose to repeat the study to track progress and the protocol can be adapted for other countries and other diseases.

Insights into incipient oral squamous cell carcinoma: a comprehensive south-american study.

BACKGROUND: To describe demographic and clinicopathological aspects of a South-American cohort of incipient oral squamous cell carcinoma patients. MATERIAL AND METHODS: A cross-sectional, observational study was performed to assess demographic and clinicopathological characteristics of incipient oral squamous cell carcinoma patients from 6 South-American institutions. RESULTS: One hundred and seven patients within the histopathological spectrum of incipient oral squamous cell carcinoma (in-situ and microinvasive) were included. Fifty-eight (54.2%) patients were men with a mean age of 60.69 years. Forty-nine (45.8%) and thirty-nine (36.5%) patients had history of tobacco and alcohol use, respectively. Clinically, most of the lesions were plaques (82.2%), ≥ 2 cm in extension (72%), affecting the lateral border of the tongue (55.1%), and soft palate (12.1%) with a mixed (white and red) appearance. Eighty-two (76.7%) lesions were predominantly white and 25 (23.3%) predominantly red. CONCLUSIONS: To the best of our knowledge, this is the largest cohort of incipient oral squamous cell carcinoma patients, which raises awareness of clinicians' inspection acuteness by demonstrating the most frequent clinical aspects of this disease, potentially improving oral cancer secondary prevention strategies.

Impact of rotavirus vaccination on diarrheal disease burden of children in South America.

INTRODUCTION: Rotavirus is a leading cause of severe diarrheal disease and death in children under five years of age worldwide. Vaccination is one of the most important public health interventions to reduce this significant burden. AREAS COVERED: This literature review examined vaccination coverage, hospitalization rate, mortality, genotypic distribution, immunogenicity, cost-effectiveness, and risk versus benefit of rotavirus vaccination in children in South America. Nine out of twelve countries in South America currently include a rotavirus vaccine in their national immunization program with coverage rates in 2022 above 90%. EXPERT OPINION: Introduction of the rotavirus vaccination has led to a marked reduction in hospitalizations and deaths from diarrheal diseases in children under 5 years, particularly infants under 1 year, in several South American countries. In Brazil, hospitalizations decreased by 59% and deaths by 21% (30-38% in infants). In Peru, hospitalizations in infants fell by 46% and deaths by 37% (56% in infants). Overall, data suggest that rotavirus vaccination has reduced rotavirus deaths by 15-50% in various South American countries. There is some evidence that immunity wanes after the age of 1-year old. Ongoing surveillance of vaccine coverage and changes in morbidity and mortality is important to maximize protection against this disease.

APOL1-Mediated Kidney Disease.

This JAMA Insights reviews the origin of APOL1 high-risk genetic variants, defines APOL1-mediated kidney disease, and discusses recommendations for screening and management.

Perkinsus spp. Occurrence in South America: A review.

Marine mollusk production is increasing worldwide, and this trend is being evidenced in South American countries, where several species of bivalves are produced, exploited, and traded. This activity brings benefits either for the ecosystem, as it is a less impactful and polluting than other aquaculture practices, and to coastal human communities, as it provides food and income. However, emergence of outbreaks by pathogens is a major concern and can put an entire developing sector at risk. Perkinsosis is a disease caused by Perkinsus spp. protozoans that affect mollusks worldwide. In this review we provide information on Perkinsus spp. among bivalves from South America. Infections by these parasites were only reported to date among coastal Atlantic bivalves of Argentina, Uruguay, and Brazil. The vast majority of cases and studies are reported from Brazil. We comprehensively review those results here. Finally, we suggest some considerations for future investigations that may expand our knowledge of these parasites.

Estimated Loss of Productivity Attributed to Cardiovascular Diseases in South America. / Estimativa de Produtividade Perdida Atribuída a Doenças Cardiovasculares na América do Sul.

BACKGROUND: Cardiovascular diseases (CVD) have significant health and economic burdens. In South America, the loss of productivity related to these diseases has not yet been well explored. OBJECTIVE: Estimate the potentially productive years of life lost (PPYLL) and loss of productivity related to premature mortality associated with CVD in South America, in 2019. METHODS: Mortality data available from the 2019 Global Burden of Disease Study were used to estimate the burden of disease attributable to CVD. For monetary calculations of productivity loss, a proxy of the human capital approach was used. Data were stratified by sex, in working age groups. RESULTS: The total number of deaths due to CVD in South America in 2019 was 754,324, and the total number of PPYLL was 2,040,973. The total permanent loss of productivity was approximately US$ 3.7 billion and US$ 7.8 billion in purchasing power parity, equivalent to 0.11% of the gross domestic product. The cost per death was US$ 22,904, and the ratio between men and women for the cost per death was 1.45. The variation in scenarios indicates that the estimates are robust, even with important differences between countries. CONCLUSIONS: CVD impose a significant economic burden on countries in South America. The characterization of this burden can support governments in the allocation of resources for the planning and execution of health policies and interventions in promotion, prevention, and recovery.

FUNDAMENTO: As doenças cardiovasculares (DCV) têm ônus sanitário e econômico significativos. Na América do Sul (AS), a perda de produtividade relacionada a estas enfermidades ainda não foi bem explorada. OBJETIVO: Estimar os anos de vida produtiva perdidos (AVPP) e a perda de produtividade relacionados a mortalidade prematura associada as DCV na AS, em 2019. MÉTODOS: Empregou-se dados de mortalidade disponíveis no Global Burden of Disease Study 2019 na estimativa da carga de doença atribuível a DCV. Para os cálculos monetários da perda da produtividade usou-se uma proxy da abordagem de capital humano. Estratificou-se por sexo, nas faixas etárias de trabalho. RESULTADOS: O número total de mortes por DCV na AS no ano de 2019 foi de 754.324 e os AVPP foram 2.040.973. A perda permanente de produtividade total foi de aproximadamente US$ 3,7 bilhões e US$ 7,8 bilhões em paridade do poder de compra, equivalente a 0,11% do produto interno bruto. O custo por morte foi de US$ 22.904, e a razão desse custo por óbito, entre homens e mulheres foi 1,45. A variação dos cenários aponta robustez nas estimativas, mesmo com diferenças importantes entre os países. CONCLUSÕES: As DCV impõem um ônus econômico significativo a este bloco de países. A caracterização deste fardo pode amparar os governos na alocação de recursos destinados ao planejamento e execução de políticas e intervenções sanitárias, sejam de promoção, prevenção ou recuperação.

Birthweights at term have increased globally: insights from a systematic review of 183 million births.

OBJECTIVE: This study aimed to assess global trends in mean birthweights at term, as reported in peer-reviewed literature. DATA SOURCES: We electronically searched PubMed, Embase, and Web of Science up to September 2023, using combinations of the search terms: "birth weight"; "birth-weight"; "birthweight"; "trend". There were no restrictions based on language or geographic area. STUDY ELIGIBILITY CRITERIA: We included all ecological and observational studies reporting mean birthweight at term as a continuous numerical variable over time. METHODS: We assessed the quality of included studies using the Dufault and Klar checklist modified by Betran et al. Univariate and multivariate linear models were used to examine the effects of time (years) and geographical origins. Subgroup analyses focused on national data sources and on data collected from 1950 onward. RESULTS: Among 6447 reviewed articles, 29 met our criteria, reporting mean birthweight data from over 183 million infants worldwide. Most studies were hospital-based (48.3%), 44.8% used national data, and a minority used municipality, community, or regional data (6.9%). Geographically, North America (31.0%) had the highest representation, followed by Asia and Europe (27.6% each), and South America and Oceania (6.9% each). Our univariate linear regression model (Model 1) revealed a significant increase in mean birthweight at term over time (4.74 g/y; 95% confidence interval, 3.95-5.53; P<.001). Model 2, incorporating continental dummy variables into the first model, confirmed this trend (3.85 g/y; 95% confidence interval, 2.96-4.74; P<.001). Model 3, focusing on available national data, did not find a significant relationship. Model 4 narrowed its focus on records from 1950 onward, reporting a robust annual increase of 7.26 g/y (95% confidence interval, 6.19-8.33; P<.001). Model 5, adjusting for the number of participants included in each study, reported a conclusive mean term birthweight increase of 1.46 g/y (95% confidence interval, 0.74-2.18; P<.001). CONCLUSION: This systematic review of 29 studies shows an increase in term birthweights over time, particularly when considering data since 1950. Limitations include study quality variations, data source diversity, and data sparsity, underscoring the need for future research to use precise gestational age distinctions and predetermined time frames to gain a deeper understanding of this trend and its implications for maternal and child health.

Assessing vulnerability for future Zika virus outbreaks using seroprevalence data and environmental suitability maps.

The 2015-17 Zika virus (ZIKV) epidemic in the Americas subsided faster than expected and evolving population immunity was postulated to be the main reason. Herd immunization is suggested to occur around 60-70% seroprevalence, depending on demographic density and climate suitability. However, herd immunity was only documented for a few cities in South America, meaning a substantial portion of the population might still be vulnerable to a future Zika virus outbreak. The aim of our study was to determine the vulnerability of populations to ZIKV by comparing the environmental suitability of ZIKV transmission to the observed seroprevalence, based on published studies. Using a systematic search, we collected seroprevalence and geospatial data for 119 unique locations from 37 studies. Extracting the environmental suitability at each location and converting to a hypothetical expected seroprevalence, we were able to determine the discrepancy between observed and expected. This discrepancy is an indicator of vulnerability and divided into three categories: high risk, low risk, and very low risk. The vulnerability was used to evaluate the level of risk that each location still has for a ZIKV outbreak to occur. Of the 119 unique locations, 69 locations (58%) fell within the high risk category, 47 locations (39%) fell within the low risk category, and 3 locations (3%) fell within the very low risk category. The considerable heterogeneity between environmental suitability and seroprevalence potentially leaves a large population vulnerable to future infection. Vulnerability seems to be especially pronounced at the fringes of the environmental suitability for ZIKV (e.g. Sao Paulo, Brazil). The discrepancies between observed and expected seroprevalence raise the question: "why did the ZIKV epidemic stop with large populations unaffected?". This lack of understanding also highlights that future ZIKV outbreaks currently cannot be predicted with confidence.

Prevalence of HTLV-1/2 infection in pregnant women in Central and South America and the Caribbean: a systematic review and meta-analysis.

BACKGROUND: Human T-lymphotropic viruses (HTLV)-1 infection is endemic in many countries of Central and South America and Caribbean (CSA&C). Neither screening nor surveillance programs exist for HTLV-1/2 infection among pregnant women in this region. Neither in Western nations with large migrant flows from HTLV-1/2 endemic regions. METHODS: Systematic review and meta-analysis of the prevalence of HTLV-1/2 infection among CSA&C pregnant women. We included studies searching EMBASE, PubMed/MEDLINE, Scopus, and Web of Science from inception to February 15, 2023. This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines. RESULTS: We identified a total of 620 studies. Only 41 were finally included in the meta-analysis. Most studies (61.0%) were from Brazil and Peru (14.6%). The total number of participants was 343,707. The pooled prevalence of HTLV-1/2 infection among CSA&C pregnant women was 1.30% (95% CI: 0.96-1.69) using anti-HTLV-1/2 antibody screening tests. There was a high heterogeneity (I2 = 98.6%). Confirmatory tests gave an HTLV-1 infection rate of 1.02% (95% CI: 0.75-1.33). CONCLUSIONS: The prevalence of HTLV-1/2 infection among CSA&C pregnant women is 1.3%, most cases being HTLV-1. This rate is greater than for other microbial agents regularly checked as part of antenatal screening (such as HIV, hepatitis B, or syphilis). Thus, HTLV-1/2 antenatal testing should be mandatory among CSA&C pregnant women everywhere.

Pacific and Atlantic sea lion mortality caused by highly pathogenic Avian Influenza A(H5N1) in South America.

We describe the evolution of the outbreak of Highly Pathogenic Avian Influenza (HPAI) A(H5N1) in sea lions (Otaria flavescens) of South America. At least 24,000 sea lions died in Peru, Chile, Argentina, Uruguay, and Brazil between January-October 2023. The most plausible route of infection is cohabiting with or foraging on infected birds. However, we urge a detailed evaluation of the sea lions actual source of infection given that the concomitant massive wild bird mortalities registered in the Pacific Ocean did not occur in the Atlantic Ocean.

Neurological and neuropsychiatric manifestations of post-COVID-19 condition in South America: a systematic review of the literature.

BACKGROUND: The post-COVID-19 condition is a major modern challenge in medicine and has a high global impact on the health of the population. OBJECTIVE: To determine the main neurological and neuropsychiatric manifestations after acute COVID-19 infection in South American countries. METHODS: This is a systematic review study, registered on the PROSPERO platform following the PRISMA model. 4131 articles were found with the search strategies used. Neurological and neuropsychiatric manifestations were investigated in individuals three months or more after acute COVID-19 infection, and older than 18 years, including studies conducted in South American countries published between 2020 and 2022. RESULTS: Six studies (four from Brazil and two from Ecuador) were analyzed. Regarding the type of study: three were cohorts, two were case reports, and one was cross-sectional. The main outcomes found were new pain (65.5%) and new chronic pain (19.6%), new headache (39.1%), daily chronic headache (13%), paresthesia (62%), in addition to neuropsychiatric diseases, such as generalized anxiety disorder (15.1%), post-traumatic stress syndrome (13.4%), depression and anxiety (13.5%), suicidal ideation (10.1%), and several cognitive disorders. CONCLUSION: Neurological and neuropsychiatric manifestations related to depression and anxiety, and cognition disorders are reported during the post-COVID-19 condition in South America. Symptoms associated with chronic pain appear to be associated with the condition. More studies on post-COVID-19 conditions are needed in the South America region.

ANTECEDENTES: A condição pós-COVID-19 é um grande desafio moderno na medicina e tem alto impacto global na saúde da população. OBJETIVO: Determinar as principais manifestações neurológicas e neuropsiquiátricas após a infecção aguda da COVID-19 nos países da América do Sul. MéTODOS: Trata-se de um estudo de revisão sistemática, registrado na plataforma PROSPERO seguindo o modelo PRISMA. Foram encontrados 4131 artigos com as estratégias de buscas empregadas. Investigaram-se manifestações neurológicas e neuropsiquiátricas em indivíduos com três meses ou mais desde a infecção aguda por COVID-19, maiores de 18 anos, incluindo estudos realizados em países da América do Sul publicados entre 2020 e 2022. RESULTADOS: Foram analisados seis estudos (quatro do Brasil e dois do Equador). Em relação ao tipo de estudo: três eram coortes, dois relatos de casos e um transversal. Os principais desfechos encontrados foram em relação à dor nova (65,5%) e dor crônica nova (19,6%), cefaleia nova (39,1%), cefaleia crônica diária (13%), parestesia (62%), além de doenças neuropsiquiátricas como transtorno de ansiedade generalizada (15,1%), síndrome do estresse pós-traumático (13,4%), depressão e ansiedade (13,5%), ideação suicida (10,1%) e diversos distúrbios cognitivos. CONCLUSãO: Manifestações neurológicas e neuropsiquiátricas relacionadas à depressão e ansiedade e distúrbios de cognição são relatados durante a condição pós-COVID-19 na América do Sul. Os sintomas associados a quadros de dor crônica parecem estar associados à condição. Mais estudos sobre condições pós COVID-19 são necessários na região da América do Sul.