Spatial associations of Hansen's disease and schistosomiasis in endemic regions of Minas Gerais, Brazil.

Background: Brazil has the second highest case count of Hansen's disease (leprosy, HD), but factors contributing to transmission in highly endemic areas of the country remain unclear. Recent studies have shown associations of helminth infection and leprosy, supporting a biological plausibility for increased leprosy transmission in areas with helminths. However, spatial analyses of the overlap of these infections are limited.

Presence of dengue virus RNA in urine and oral fluid of laboratory-confirmed dengue patients: Implications for wastewater surveillance.

Introduction: Dengue cases in the Americas in 2024 have reached record highs, especially in Brazil. However, surveillance remains suboptimal and new methods are needed to monitor Dengue Virus (DENV) spread. To assess whether wastewater-based epidemiology would be a useful tool, we investigated the presence of DENV RNA in dengue patients' urine and oral fluid from an endemic area to inform how shedding in these fluids occurs and provide insight for wastewater surveillance.

Anopheles gambiae Re-Emergence and Resurgent Malaria Transmission in Eastern Rwanda, 2010-2020.

Rwanda achieved unprecedented malaria control gains from 2000 to 2010, but cases increased 20-fold between 2011 and 2017. Vector control challenges and environmental changes were noted as potential explanations, but no studies have investigated causes of the resurgence or identified which vector species drove transmission. We conducted a retrospective study in four sites in eastern Rwanda that conducted monthly entomological surveillance and outpatient malaria care.

An analysis of the social, cultural, and ecological factors that affect the implementation of biosecurity measures on smallholder commercial swine farms in Italy in the context of an emerging African Swine Fever outbreak.

African Swine Fever (ASF) is a contagious viral disease that infects wild and domesticated swine. In early 2022, the virus was found in wild boar in the Apennine mountains of mainland Italy. Since then, it has spread from wild boar to domesticated swine.

Detection of Chikungunya Virus RNA in Oral Fluid and Urine: An Alternative Approach to Diagnosis?

To evaluate whether oral fluids (OF) and urine can serve as alternative, non-invasive samples to diagnose chikungunya virus (CHIKV) infection via RT-qPCR, we employed the same RNA extraction and RT-qPCR protocols on paired serum, OF and urine samples collected from 51 patients with chikungunya during the acute phase of the illness. Chikungunya patients were confirmed through RT-qPCR in acute-phase sera (N = 19), IgM seroconversion between acute- and convalescent-phase sera (N = 12), or IgM detection in acute-phase sera (N = 20). The controls included paired serum, OF and urine samples from patients with non-arbovirus acute febrile illness (N = 28) and RT-PCR-confirmed dengue (N = 16).

Chikungunya: a decade of burden in the Americas.

In the Americas, one decade following its emergence in 2013, chikungunya virus (CHIKV) continues to spread and cause epidemics across the region. To date, 3.7 million suspected and laboratory-confirmed chikungunya cases have been reported in 50 countries or territories in the Americas.

Dynamics of chikungunya virus transmission in the first year after its introduction in Brazil: A cohort study in an urban community.

Background: The first chikungunya virus (CHIKV) outbreaks during the modern scientific era were identified in the Americas in 2013, reaching high attack rates in Caribbean countries. However, few cohort studies have been performed to characterize the initial dynamics of CHIKV transmission in the New World.

Methodology/principal Findings: To describe the dynamics of CHIKV transmission shortly after its introduction in Brazil, we performed semi-annual serosurveys in a long-term community-based cohort of 652 participants aged ≥5 years in Salvador, Brazil, between Feb-Apr/2014 and Nov/2016-Feb/2017.

Building the vector in: construction practices and the invasion and persistence of Anopheles stephensi in Jigjiga, Ethiopia.

Anopheles stephensi is a major vector of malaria in Asia and the Arabian Peninsula, and its recent invasion into Africa poses a major threat to malaria control and elimination efforts on the continent. The mosquito is well adapted to urban environments, and its presence in Africa could potentially lead to an increase in malaria transmission in cities. Most of the knowledge about An stephensi ecology in Africa has been generated from studies conducted during the rainy season, when vectors are most abundant.

Spatial prediction of Crimean Congo hemorrhagic fever virus seroprevalence among livestock in Uganda.

Crimean-Congo Hemorrhagic Fever (CCHF) is a viral disease that can infect humans via contact with tick vectors or livestock reservoirs and can cause moderate to severe disease. The first human case of CCHF in Uganda was identified in 2013. To determine the geographic distribution of the CCHF virus (CCHFV), serosampling among herds of livestock was conducted in 28 Uganda districts in 2017.

Intersections of climate change, migration, and health: experiences of first-generation migrants from Latin America to the Atlanta-metropolitan area.

Climate change is an important driver of migration, but little research exists on whether migrant communities in the U.S. identify climate change-related factors as reasons for migrating.

Direct mosquito feedings on dengue-2 virus-infected people reveal dynamics of human infectiousness.

Dengue virus (DENV) transmission from humans to mosquitoes is a poorly documented, but critical component of DENV epidemiology. Magnitude of viremia is the primary determinant of successful human-to-mosquito DENV transmission. People with the same level of viremia, however, can vary in their infectiousness to mosquitoes as a function of other factors that remain to be elucidated.

Oviposition Preferences of Aedes aegypti in Msambweni, Kwale County, Kenya.

Aedes aegypti is the primary vector of dengue fever virus (DENV) worldwide. Infusions made from organic materials have been shown to act as oviposition attractants for Ae. aegypti; however, studies on locally suitable infusion materials are lacking.

Density of Aedes aegypti (Diptera: Culicidae) in a low-income Brazilian urban community where dengue, Zika, and chikungunya viruses co-circulate.

Background: Low-income urban communities in the tropics often lack sanitary infrastructure and are overcrowded, favoring Aedes aegypti proliferation and arboviral transmission. However, as Ae. aegypti density is not spatially homogeneous, understanding the role of specific environmental characteristics in determining vector distribution is critical for planning control interventions.

Inapparent infections shape the transmission heterogeneity of dengue.

Transmission heterogeneity, whereby a disproportionate fraction of pathogen transmission events result from a small number of individuals or geographic locations, is an inherent property of many, if not most, infectious disease systems. For vector-borne diseases, transmission heterogeneity is inferred from the distribution of the number of vectors per host, which could lead to significant bias in situations where vector abundance and transmission risk at the household do not correlate, as is the case with dengue virus (DENV). We used data from a contact tracing study to quantify the distribution of DENV acute infections within human activity spaces (AS), the collection of residential locations an individual routinely visits, and quantified measures of virus transmission heterogeneity from two consecutive dengue outbreaks (DENV-4 and DENV-2) that occurred in the city of Iquitos, Peru.

Geostatistical Modeling and Prediction of Rift Valley Fever Seroprevalence among Livestock in Uganda.

Uganda reported cases of Rift Valley fever virus (RVFV) for the first time in almost 50 years in 2016, following an outbreak of Rift Valley fever (RVF) that caused four human infections, two of which resulted in death. Subsequent outbreak investigation serosurveys found high seroprevalence of IgG antibodies without evidence of acute infection or IgM antibodies, suggesting the possibility of undetected RVFV circulation prior to the outbreak. After the 2016 outbreak investigation, a serosurvey was conducted in 2017 among domesticated livestock herds across Uganda.

Quantifying heterogeneities in arbovirus transmission: Description of the rationale and methodology for a prospective longitudinal study of dengue and Zika virus transmission in Iquitos, Peru (2014-2019).

Current knowledge of dengue virus (DENV) transmission provides only a partial understanding of a complex and dynamic system yielding a public health track record that has more failures than successes. An important part of the problem is that the foundation for contemporary interventions includes a series of longstanding, but untested, assumptions based on a relatively small portion of the human population; i.e.

Pupal productivity of larval habitats of Aedes aegypti in Msambweni, Kwale County, Kenya.

Aedes aegypti is an important vector of several arboviruses including dengue and chikungunya viruses. Accurate identification of larval habitats of Ae. aegypti is considered an essential step in targeted control.

Multi-Year Comparison of Community- and Species-Level West Nile Virus Antibody Prevalence in Birds from Atlanta, Georgia and Chicago, Illinois, 2005-2016.

West Nile virus (WNV) is prevalent in the United States but shows considerable variation in transmission intensity. The purpose of this study was to compare patterns of WNV seroprevalence in avian communities sampled in Atlanta, Georgia and Chicago, Illinois during a 12-year period (Atlanta 2010-2016; Chicago 2005-2012) to reveal regional patterns of zoonotic activity of WNV. WNV antibodies were measured in wild bird sera using ELISA and serum neutralization methods, and seroprevalence among species, year, and location of sampling within each city were compared using binomial-distributed generalized linear mixed-effects models.

Night Time Extension of Aedes aegypti Human Blood Seeking Activity.

This study examined whether Aedes aegypti extends its human blood seeking activity into night hours. Human landing catches (HLC) were conducted hourly from early morning (04:30) to late evening (21:30) in urban and rural sites in Kisumu County in western Kenya, and in Kwale County at the coast. Out of 842 female Ae.

Isolation of Heartland Virus from Lone Star Ticks, Georgia, USA, 2019.

Report of a human death and exposure of white-tailed deer to Heartland virus (HRTV) in Georgia, USA, prompted the sampling of questing ticks during 2018-2019 in 26 sites near where seropositive deer were captured and the residence of the human case-patient. We processed 9,294 Amblyomma americanum ticks in pools by virus isolation in Vero E6 cells and reverse transcription PCR. Positive pools underwent whole-genome sequencing.

Diversity of Mosquitoes (Diptera: Culicidae) in an Atlantic Forest Urban Park, Salvador, Brazil.

We identified mosquito species (Diptera: Culicidae) in an Atlantic Forest fragment located in a large urban park in Salvador, Brazil, one year after a citywide epizootic of yellow fever virus (YFV). Between May 2 and August 2, 2018, adult mosquitoes were collected using the human attraction method, followed by trapping with hand-nets, and CO2-baited light traps placed at ground level and in the canopy. We collected a total of 11,914 mosquitoes, which belonged to three tribes, five genera, and at least seven species.

Assessing the Effects of Cooking Fuels on Anopheles Mosquito Behavior: An Experimental Study in Rural Rwanda.

Globally, cleaner cooking fuels are increasingly promoted to reduce household air pollution. However, there is concern that reductions in smoke from biomass fuels could lead to more favorable conditions for mosquitoes and potentially increase vectorborne disease risk. We investigated household entry, host-seeking, household exit, and mortality among Anopheles mosquitoes across three cooking fuel types: wood, charcoal, and liquid petroleum gas (LPG) in six experimental huts in Rwanda.

Considerations for Improving Reporting and Analysis of Date-Based COVID-19 Surveillance Data by Public Health Agencies.

More than a year after the first domestic COVID-19 cases, the United States does not have national standards for COVID-19 surveillance data analysis and public reporting. This has led to dramatic variations in surveillance practices among public health agencies, which analyze and present newly confirmed cases by a wide variety of dates. The choice of which date to use should be guided by a balance between interpretability and epidemiological relevance.