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From 2016 to 2019, Southeastern Brazil faced an outbreak of yellow fever (YF) affecting both humans and New World primates (NWP). The outbreak was associated with a marked increase in traumatic lesions in NWP in the affected regions. Non-thrombotic pulmonary embolization (NTPE) can be a consequence of massive traumatic events, and it is rarely reported in human and veterinary medicine. Here, we describe NTPE of the brain, liver, and bone marrow in free-ranging NWP, highlighting the epidemiological aspects of these findings and the lesions associated with this condition, including data on traumatic injuries in wild NWP populations during the course of a recent YF outbreak. A total of 1078 NWP were necropsied from January 2017 to July 2019. Gross traumatic injuries were observed in 444 marmosets (44.3%), 10 howler monkeys (23.2%), 9 capuchins (31.0%), 1 titi-monkey (50.0%), and 1 golden lion tamarin (33.3%). NTPE was observed in 10 animals, including 9 marmosets (2.0%) and 1 howler monkey (10.0%). NTPE was identified in the lung and comprised hepatic tissue in 1 case, brain tissue in 1 case, and bone marrow tissue in 8 cases. Although uncommon, it is important to consider NTPE with pulmonary vascular occlusion during the critical care of traumatized NWP. In addition, this study highlights the importance of conservational strategies and environmental education focusing on One Health, not only to protect these free-ranging NWP populations but also to maintain the efficacy of epidemiological surveillance programs.

Blood feeding and host-seeking behaviors of a mosquito play an imperative role in determining its vectorial capacity in transmitting pathogens. Unfortunately, limited information is available regarding blood feeding behavior of Anopheles species in Malaysia. Collection of resting Anopheles mosquitoes for blood meal analysis poses a great challenge especially for forest dwelling mosquitoes. Therefore, a laboratory-based study was conducted to evaluate the potential use of mosquitoes caught using human landing catch (HLC) for blood meal analysis, and subsequently to document blood feeding behavior of local Anopheles mosquitoes in Peninsular Malaysia. The laboratory-based experiment from this study revealed that mosquitoes caught using HLC had the potential to be used for blood meal analysis. Besides HLC, mosquitoes were also collected using manual aspirator and Mosquito Magnet. Overall, 47.4% of 321 field-caught Anopheles mosquitoes belonging to six species were positive for vertebrate host DNA in their blood meal. The most frequent blood meal source was human (45.9%) followed by wild boar (27.4%), dog (15.3%) and monkey (7.5%). Interestingly, only Anopheles cracens and Anopheles introlatus (Leucosphyrus Group) fed on monkey. This study further confirmed that members of the Leucosphyrus Group are the predominant vectors for knowlesi malaria transmission in Peninsular Malaysia mainly due to their simio-anthropophagic feeding behavior.

Background: In South and Central America, Plasmodium malariae/Plasmodium brasilianum, Plasmodium vivax, Plasmodium simium, and Plasmodium falciparum has been reported in New World primates (NWP). Specifically in Costa Rica, the presence of monkeys positive to P. malariae/P brasilianum has been identified in both captivity and in the wild. The aim of the present study was to determine the presence of P. brasilianum, P. falciparum, and P. vivax, and the potential distribution of these parasites-infecting NWP from Costa Rica. Methods: The locations with PCR (Polymerase Chain Reaction) positive results and bioclimatic predictors were used to construct ecological niche models based on a modelling environment that uses the Maxent algorithm, named kuenm, capable to manage diverse settings to better estimate the potential distributions and uncertainty indices of the potential distribution. Results: PCR analysis for the Plasmodium presence was conducted in 384 samples of four primates (Howler monkey [n = 130], White-face monkey [n = 132], Squirrel monkey [n = 50], and red spider monkey [n = 72]), from across Costa Rica. Three Plasmodium species were detected in all primate species (P. falciparum, P. malariae/P. brasilianum, and P. vivax). Overall, the infection prevalence was 8.9%, but each Plasmodium species ranged 2.1–3.4%. The niche model approach showed that the Pacific and the Atlantic coastal regions of Costa Rica presented suitable climatic conditions for parasite infections. However, the central pacific coast has a more trustable prediction for malaria in primates. Conclusions: The results indicate that the regions with higher suitability for Plasmodium transmission in NWP coincide with regions where most human cases have been reported. These regions were also previously identified as areas with high suitability for vector species, suggesting that enzootic and epizootic cycles occur. Antecedentes: En América del Sur y Central, se ha reportado la presencia de Plasmodium malariae/Plasmodium brasilianum, Plasmodium vivax, Plasmodium simium y Plasmodium falciparum en primates del Nuevo Mundo (PNM). Concretamente en Costa Rica, se ha identificado la presencia de monos positivos a P. malariae/P brasilianum tanto en cautividad como en libertad. El objetivo del presente estudio fue determinar la presencia de P. brasilianum, P. falciparum y P. vivax, y la distribución potencial de estos parásitos que infectan a los PNM de Costa Rica. Métodos: Las localidades con resultados positivos a la PCR (Reacción en Cadena de la Polimerasa) y los predictores bioclimáticos fueron utilizados para construir modelos de nicho ecológico basados en un entorno de modelización que utiliza el algoritmo Maxent, denominado kuenm, capaz de manejar diversos escenarios para estimar mejor las distribuciones potenciales y los índices de incertidumbre de la distribución potencial. Resultados: Se realizó un análisis de PCR para detectar la presencia de Plasmodium en 384 muestras de cuatro primates (mono aullador [n = 130], mono cara blanca [n = 132], mono ardilla [n = 50] y mono araña rojo [n = 72]), de toda Costa Rica. Se detectaron tres especies de Plasmodium en todas las especies de primates (P. falciparum, P. malariae/P. brasilianum y P. vivax). En general, la prevalencia de la infección fue del 8,9%, pero cada especie de Plasmodium osciló entre el 2,1-3,4%. El enfoque del modelo de nicho mostró que las regiones costeras del Pacífico y del Atlántico de Costa Rica presentaban condiciones climáticas adecuadas para las infecciones del parásito. Sin embargo, la costa del Pacífico central presenta una predicción más fiable para la malaria en primates. Conclusiones: Los resultados indican que las regiones con mayor aptitud para la transmisión de Plasmodium en el PNW coinciden con las regiones donde se han reportado más casos en humanos. Estas regiones también fueron identificadas previamente como zonas con alta idoneidad para las especies vectoriales, lo que sugiere que se producen ciclos enzoóticos y epizoóticos. This research was conducted in the framework of the project “Estudios epidemiológicos (Malaria, Dengue, Virus del Oeste del Nilo, Encefalitis Equina Venezolana), genéticos, etológicos, poblacionales y de hábitat en monos de Costa Rica” sponsored by FEES-CONARE, and with participation of UNA-ITCR-UCR-UNED. Escuela de Medicina Veterinaria

Ebola virus (EBOV) is a negative single-stranded RNA virus within the

Rhesus cytomegalovirus (RhCMV) infection of rhesus macaques (Macaca mulatta) is a valuable nonhuman primate model of human CMV (HCMV) persistence and pathogenesis. In vivo studies predominantly use tissue culture-adapted variants of RhCMV that contain multiple genetic mutations compared to wild-type (WT) RhCMV. In many studies, animals have been inoculated by non-natural routes (e.g., subcutaneous, intravenous) that do not recapitulate disease progression via the normative route of mucosal exposure. Accordingly, the natural history of RhCMV would be more accurately reproduced by infecting macaques with strains of RhCMV that reflect the WT genome using natural routes of mucosal transmission. Herein, we tested two WT-like RhCMV strains, UCD52 and UCD59, and demonstrated that systemic infection and frequent, high-titer viral shedding in bodily fluids occurred following oral inoculation. RhCMV disseminated to a broad range of tissues, including the central nervous system and reproductive organs. Commonly infected tissues included the thymus, spleen, lymph nodes, kidneys, bladder, and salivary glands. Histological examination revealed prominent nodular hyperplasia in spleens and variable levels of lymphoid lymphofollicular hyperplasia in lymph nodes. One of six inoculated animals had limited viral dissemination and shedding, with commensurately weak antibody responses to RhCMV antigens. These data suggest that long-term RhCMV infection parameters might be restricted by local innate factors and/or de novo host immune responses in a minority of primary infections. Together, we have established an oral RhCMV infection model that mimics natural HCMV infection. The virological and immunological parameters characterized in this study will greatly inform HCMV vaccine designs for human immunization. IMPORTANCE Human cytomegalovirus (HCMV) is globally ubiquitous with high seroprevalence rates in all communities. HCMV infections can occur vertically following mother-to-fetus transmission across the placenta and horizontally following shedding of virus in bodily fluids in HCMV infected hosts and subsequent exposure of susceptible individuals to virus-laden fluids. Intrauterine HCMV has long been recognized as an infectious threat to fetal growth and development. Since vertical HCMV infections occur following horizontal HCMV transmission to the pregnant mother, the nonhuman primate model of HCMV pathogenesis was used to characterize the virological and immunological parameters of infection following primary mucosal exposures to rhesus cytomegalovirus.

Introduction. The relevance of studying the circulation of human respiratory viruses among laboratory primates is associated with the need to test vaccines and antiviral drugs against these infections on monkeys.The aim of this work was to study the prevalence of serological and molecular markers of human respiratory viral infections in laboratory primates born at the Adler Primate Center and in imported monkeys.Material and methods. Blood serum samples (n = 1971) and lung autopsy material (n = 26) were obtained from different monkey species. These samples were tested for the presence of serological markers of measles, parainfluenza (PI) types 1, 2, 3, influenza A and B, respiratory syncytial (RS) and adenovirus infections using enzyme immunoassay (ELISA). Detection of RS virus, metapneumovirus, PI virus types 1–4, rhinovirus, coronavirus, and adenoviruses B, C, E and bocavirus nucleic acids in this material was performed by reverse transcription polymerase chain reaction (RT-PCR).Results and discussion. The overall prevalence of antibodies (Abs) among all monkeys was low and amounted 11.3% (95% CI: 9.2–13.7%, n = 811) for measles virus, 8.9% (95% CI: 6.2–12.2%, n = 381) for PI type 3 virus, 2.5% (95% CI: 0.8–5.6%, n = 204) for PI type 1 virus, and 7.7% (95% CI: 3.8–13.7%, n = 130) for adenoviruses. When testing 26 autopsy lung samples from monkeys of different species that died from pneumonia, 2 samples from Anubis baboons (Papio аnubis) were positive for of parainfluenza virus type 3 RNA.Conclusion. Our data suggest the importance of the strict adherence to the terms of quarantine and mandatory testing of monkey sera for the presence of IgM antibodies to the measles virus that indicate the recent infection. The role of PI virus type 3 in the pathology of the respiratory tract in Anubis baboons has been established.

We performed coproparasitological testing of free-living golden-headed lion tamarins, Leontopithecus chrysomelas, using the Hoffmann-Pons-Janner method. In total, we collected 118 samples from ten groups: four living in Federal Protected Area and six living in Non-Protected Areas of cocoa farms. Eggs from parasites of the Acanthocephala phylum and Spiruridae, Ancylostomatidae, Ascarididae and Oxyuridae families were identified, as well as the genus Strongyloides (Nematode: Strongyloididae) and phylum Apicomplexa. This is the first description of infection with coccidian, Trichuridae family and Strongyloides spp. in L. chrysomelas. A total of 48% (n= 57) of the animals were infected and the highest prevalence (37.2±SD 8.72, n = 44) was for Acanthocephalidae, followed by Spiruridae (8.5±SD 5.03, n = 10). There was no difference in parasite prevalence by age classes or sex. However, we found higher diversity and prevalence of parasites in animals living in the Federal Protected Area. These results suggest that intestinal parasites may be influenced by environmental factors, such as the management of the areas where the animals live, in addition to the feeding behavior of L. chrysomelas and distinct transmission strategies of parasites. The combination of ecological and demographic data combined with parasitological studies may contribute to conservation programs for this species. Resumo Foram realizados testes coproparasitológicos de micos-leões-dourados de vida livre, Leontopithecus chrysomelas, usando-se o método de Hoffmann-Pons-Janner. No total, foram coletadas 118 amostras de dez grupos: quatro grupos residentes em Área de Conservação Federal e seis grupos em Área não protegida de fazendas de cacau. Ovos de parasitas do filo Acantocephala e das famílias Spiruridae, Ancylostomatidae, Ascarididae, Oxyuridae foram identificados, bem como o gênero Strongyloides (Nematoda: Strongyloididae) e o filo Apicomplexa. Esta é a primeira descrição de infecção de coccídeos, família Trichuridae e Strongyloides spp. em L. chrysomelas. Um total de 48% (n = 57) dos animais estavam parasitados e a maior prevalência (37,2 ±DP 8,72, n = 44) foi para Acanthocephalan, seguido por Spiruridae (8,5±DP 5,03, n = 10). Não houve diferença na prevalência do táxon de parasita por idade ou sexo. No entanto, foi encontrada maior diversidade e prevalência de parasitas em animais que vivem na Unidade de Conservação Federal. Esses resultados sugerem que os parasitas intestinais podem ser influenciados por fatores ambientais, como o manejo das áreas, além do comportamento alimentar de L. chrysomelas e distintas estratégias de transmissão dos parasitas. A combinação de dados ecológicos e demográficos com estudos parasitológicos podem contribuir para programas de conservação dessa espécie.

The novel coronavirus SARS-CoV-2, the causative agent of COVID-19 disease, has killed over five million people worldwide as of December 2021 with infections rising again due to the emergence of highly transmissible variants. Animal models that faithfully recapitulate human disease are critical for assessing SARS-CoV-2 viral and immune dynamics, for understanding mechanisms of disease, and for testing vaccines and therapeutics. Pigtail macaques (PTM, Macaca nemestrina) demonstrate a rapid and severe disease course when infected with simian immunodeficiency virus (SIV), including the development of severe cardiovascular symptoms that are pertinent to COVID-19 manifestations in humans. We thus proposed this species may likewise exhibit severe COVID-19 disease upon infection with SARS-CoV-2. Here, we extensively studied a cohort of SARS-CoV-2-infected PTM euthanized either 6- or 21-days after respiratory viral challenge. We show that PTM demonstrate largely mild-to-moderate COVID-19 disease. Pulmonary infiltrates were dominated by T cells, including CD4+ T cells that upregulate CD8 and express cytotoxic molecules, as well as virus-targeting T cells that were predominantly CD4+. We also noted increases in inflammatory and coagulation markers in blood, pulmonary pathologic lesions, and the development of neutralizing antibodies. Together, our data demonstrate that SARS-CoV-2 infection of PTM recapitulates important features of COVID-19 and reveals new immune and viral dynamics and thus may serve as a useful animal model for studying pathogenesis and testing vaccines and therapeutics., Author summary The COVID-19 pandemic has claimed the lives of millions in a span of less than two years. Despite the development of several highly effective vaccines, many millions remain unvaccinated, and several highly transmissible variants have emerged, clearly suggesting the need for new approaches to treat those that become severely ill. The development of new drugs will rely on having animal models that reproduce the most severe disease seen in humans. To date, nonhuman primate models have not exhibited this severe disease. In this study we tested whether pigtail macaques (PTM) might exhibit such severe disease, based on previous work showing this species is prone to more rapid and severe disease when infected with other viruses.