Clinical and epidemiological characteristics of Madariaga and Venezuelan equine encephalitis virus infections.

Madariaga virus (MADV) and Venezuelan equine encephalitis virus (VEEV) are emerging arboviruses affecting rural and remote areas of Latin America. However, there are limited clinical and epidemiological reports available, and outbreaks are occurring at an increasing frequency. We addressed this gap by analyzing all the available clinical and epidemiological data of MADV and VEEV infections recorded since 1961 in Panama. A total of 168 of human alphavirus encephalitis cases were detected in Panama from 1961 to 2023. Here we describe the clinical signs and symptoms and epidemiological characteristics of these cases, and also explored signs and symptoms as potential predictors of encephalitic alphavirus infection when compared to those of other arbovirus infections occurring in the region. Our results highlight the challenges clinical diagnosis of alphavirus disease in endemic regions with overlapping circulation of multiple arboviruses.

A retrospective review of COVID-19 testing and mitigation strategies at a psychiatric hospital and subsequent COVID-19 acquisition.

BACKGROUND: Behavioral health settings present increased challenges in preventing the transmission of infectious agents. Characterizing the relative effectiveness of various strategies, including testing for asymptomatic carriage of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, will inform transmission reduction efforts in behavioral health settings. METHODS: A single-center retrospective study was conducted in an inpatient behavioral health hospital by reviewing COVID-19 mitigation and testing strategies with information collected from discharges between July 1, 2020 and February 28, 2021. RESULTS: During the study period, there were 3,694 total discharges and 3,229 unique admitted patients, including 86 (2.7%) patients who had positive SARS-CoV-2 polymerase chain reaction test results. Preadmission testing from noncongregate care settings (38, 44.1%), and testing after an in-hospital exposure (27, 31.4%) were the most common indications for testing among patients with a positive test. Up to 29 (33.7%) potentially acquired the infection during their hospitalization. Asymptomatic screening tests identified approximately two-thirds (55, 64.0%) of potentially contagious patients. CONCLUSION: Asymptomatic screening testing on admission and after exposure and universal masking were strong interventions to prevent SARS-CoV-2 transmission in this investigation Future studies of SARS-CoV-2 and other pathogens in behavioral health settings should endeavor to characterize the effectiveness of infection prevention interventions.

Resurgence risk for malaria, and the characterization of a recent outbreak in an Amazonian border area between French Guiana and Brazil.

BACKGROUND: In 2017, inhabitants along the border between French Guiana and Brazil were affected by a malaria outbreak primarily due to Plasmodium vivax (Pv). While malaria cases have steadily declined between 2005 and 2016 in this Amazonian region, a resurgence was observed in 2017. METHODS: Two investigations were performed according to different spatial scales and information details: (1) a local study on the French Guiana border, which enabled a thorough investigation of malaria cases treated at a local village health center and the entomological circumstances in the most affected neighborhood, and (2) a regional and cross-border study, which enabled exploration of the regional spatiotemporal epidemic dynamic. Number and location of malaria cases were estimated using French and Brazilian surveillance systems. RESULTS: On the French Guianese side of the border in Saint-Georges de l'Oyapock, the attack rate was 5.5% (n = 4000), reaching 51.4% (n = 175) in one Indigenous neighborhood. Entomological findings suggest a peak of Anopheles darlingi density in August and September. Two female An. darlingi (n = 1104, 0.18%) were found to be Pv-positive during this peak. During the same period, aggregated data from passive surveillance conducted by Brazilian and French Guianese border health centers identified 1566 cases of Pv infection. Temporal distribution during the 2007-2018 period displayed seasonal patterns with a peak in November 2017. Four clusters were identified among epidemic profiles of cross-border area localities. All localities of the first two clusters were Brazilian. The localization of the first cluster suggests an onset of the outbreak in an Indigenous reservation, subsequently expanding to French Indigenous neighborhoods and non-Native communities. CONCLUSIONS: The current findings demonstrate a potential increase in malaria cases in an area with otherwise declining numbers. This is a transborder region where human mobility and remote populations challenge malaria control programs. This investigation illustrates the importance of international border surveillance and collaboration for malaria control, particularly in Indigenous villages and mobile populations.

Tuberculosis (TB) outbreak in a closed Aotus monkey breeding colony: Epidemiology, diagnosis and TB screening using antibody and interferon-gamma release testing.

Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) is a devastating and terminal disease in non-human primates (NHPs). Regular TB screenings using the intradermal tuberculin test (TST) have been the mainstay of TB surveillance and control in NHPs. Historically, Aotus monkeys have been considered less susceptible to TB than other NHPs. Here we present the diagnosis and epidemiology of a TB outbreak at The Gorgas Memorial Institute Aotus colony in Panama, and the results of two cross-sectional randomized TB screening studies, using antibody (Ab) and IFN-gamma release assay testing. RESULTS: Epidemiological and spatial analysis confirmed that the outbreak was the result of a continuing intermittent exposure, with human to monkey transmission as the most likely source. During the outbreak that lasted five months (January-June 2015), Mycobacterium kansassi and MTB were isolated from lung caseous granulomas in 1/7 and 3/7 TB suspicious animals respectively. Furthermore, MTB was detected by qRT-PCR in formalin fixed lung and liver granulomas in 2/7 and 1/6 monkeys respectively, suggesting an aerosol route of infection. Likewise, a random sample that included 63 / 313 adult (>2 year-old) monkeys, screened for latent TB with the Primagam® IFN-gamma release assay, between March-May, 2016, were all non-reactors; indicating that the outbreak was self-limiting and the colony was likely free or latent TB infection. Control measures included, quarantine, disinfection and TST screening of all personnel. In conclusion, this study demonstrates that Aotus are highly susceptible to TB, therefore, TB prevention measures should be strictly enforced in Aotus monkey colonies.

Hantaviruses and a neglected environmental determinant.

Most human pathogenic hantaviruses cause severe hemorrhagic fevers with a high rate of fatalities, such as occurs due to the genotypes causing hantavirus cardiopulmonary syndrome carried by the New World Sigmodontinae and Neotominae rodents. An increasing number of outbreaks and the possibility of cases spreading over international borders have led to greater interest in these viruses and the environmental determinants that facilitate their transmission. Rodents, shrews, moles and bats act as reservoir hosts of hantaviruses, and within the hantavirus transmission flow, the prevalence and distribution of infection in reservoir hosts is influenced by a range of factors. Climate change and landscape alteration affect hantavirus transmission, but the outcomes can differ among different hantaviruses and for the same virus in differentbiomes. However, it is evident that the underlying mechanisms that mediate hantavirus transmission are largely unknown, so that much work remains to be done regarding the transmission dynamics of hantaviruses. Overall, our review highlights the importance of examining interactions over several trophic levels and the underlying mechanisms (density and trait-mediated indirect effects) linking predation risk and hantavirus transmission, to develop an ecological framework to understand disease in natural, preserved and degraded systems.

Pertussis in the central-west region of Brazil: one decade study

In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months.

Pertussis in the central-west region of Brazil: one decade study.

In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months.