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We surveyed the presence of herpesvirus, flavivirus, and coronavirus in 20 Magnificent Frigatebirds (Fregata magnificens) from the protected Alcatrazes Island, Alcatrazes archipelago, Brazil. One adult female was positive for herpesvirus (5% occurrence; 95% confidence interval –5.5 to 15.5), whereas none of the samples were PCR-positive for flavivirus or coronavirus. The obtained herpesvirus was highly similar to the one responsible for annual mortality of Magnificent Frigatebird chicks on Grand Connétable Island, French Guiana; however, no episodes of mass mortality have been recorded in the birds from Alcatrazes. Our findings indicate that this virus may be widespread in Magnificent Frigatebirds of the southwestern Atlantic. The observed differences in morbidity and mortality may be the result of basal immunosuppression of the birds from French Guiana related to environmental or nutritional conditions. The Alcatrazes archipelago sustains the largest frigatebird breeding colony of the southern Atlantic; future monitoring studies with larger sampling sizes are needed to further determine the epidemiologic relevance of the detected herpesviruses, as well as other viruses (e.g., flaviviruses, coronaviruses, avian influenza virus), in seabirds of Alcatrazes Island. [ABSTRACT FROM AUTHOR]

Hemotropic Mycoplasma spp. (hemoplasmas) are uncultivable bacteria that infect mammals, including humans. We detected a potentially novel hemoplasma species in blood samples from wild river dolphins in the Amazon River Basin, Brazil. Further investigation could determine pathogenicity and zoonotic potential of the detected hemoplasma. [ABSTRACT FROM AUTHOR]

A major outbreak of yellow fever (YF) occurred in Brazil during 2016-2018. Epizootics in New World nonhuman primates are sentinel events for YF virus circulation. However, genus-specific susceptibilities and suitability for YF surveillance remain poorly understood. We obtained and compared epidemiologic, histopathologic, immunohistochemical, and molecular results from 93 human and 1,752 primate cases submitted during the recent YF outbreak in Brazil (2017), with the support of the Brazilian National YF Surveillance Program. We detected heterogeneous YF-associated profiles among the various genera of primates we analyzed. Alouatta primates were the most reliable sentinel; Sapajus and Callicebus primates had higher viral loads but lower proportional mortality rates. Callithrix primates were the least sensitive, showing lower viral loads, lower proportional mortality rates, and no demonstrable YF virus antigen or extensive lesions in liver, despite detectable viral RNA. These differences in susceptibility, viral load, and mortality rates should be considered in strategic surveillance of epizootics and control measures for YF. [ABSTRACT FROM AUTHOR]

Background: The merozoite surface protein 1 (MSP1) gene encodes the major surface antigen of invasive forms of the Plasmodium erythrocytic stages and is considered a candidate vaccine antigen against malaria. Due to its polymorphisms, MSP1 is also useful for strain discrimination and consists of a good genetic marker. Sequence diversity in MSP1 has been analyzed in field isolates of three human parasites: P. falciparum, P. vivax, and P. ovale. However, the extent of variation in another human parasite, P. malariae, remains unknown. This parasite shows widespread, uneven distribution in tropical and subtropical regions throughout South America, Asia, and Africa. Interestingly, it is genetically indistinguishable from P. brasilianum, a parasite known to infect New World monkeys in Central and South America.Methods: Specific fragments (1 to 5) covering 60 % of the MSP1 gene (mainly the putatively polymorphic regions), were amplified by PCR in isolates of P. malariae and P. brasilianum from different geographic origin and hosts. Sequencing of the PCR-amplified products or cloned PCR fragments was performed and the sequences were used to construct a phylogenetic tree by the maximum likelihood method. Data were computed to give insights into the evolutionary and phylogenetic relationships of these parasites.Results: Except for fragment 4, sequences from all other fragments consisted of unpublished sequences. The most polymorphic gene region was fragment 2, and in samples where this region lacks polymorphism, all other regions are also identical. The low variability of the P. malariae msp1 sequences of these isolates and the identification of the same haplotype in those collected many years apart at different locations is compatible with a low transmission rate. We also found greater diversity among P. brasilianum isolates compared with P. malariae ones. Lastly, the sequences were segregated according to their geographic origins and hosts, showing a strong genetic and geographic structure.Conclusions: Our data show that there is a low level of sequence diversity and a possible absence of allelic dimorphism of MSP1 in these parasites as opposed to other Plasmodium species. P. brasilianum strains apparently show greater divergence in comparison to P. malariae, thus P. malariae could derive from P. brasilianum, as it has been proposed. [ABSTRACT FROM AUTHOR]

Simian foamy viruses (SFV) infect a wide range of Old World and Neotropical primates (NP). Unlike Old World primates, little is known about the diversity and prevalence of SFV in NP, mainly from a free-living population. Phylogenetic analyses have shown that SFV coevolved with their hosts. However, viral strains infecting Leontopithecus chrysomelas did not behave as expected for this hypothesis. The purpose of this study was to determine the eco-epidemiological profile and molecular characterization of SFV in a recently captured invasive population of L. chrysomelas located in Niteroi/RJ using buccal swab as an alternative collection method. A prevalence of 34.8% (32/92) and a mean viral load of 4.7 log copies of SFV/106 cells were observed. With respect to time since capture, SFV prevalence was significantly higher in the group of animals sampled over 6 months after capture (55.2%) than in those more recently captured (25.4%) (p = 0.005). Infected solitary animals can contribute to SFV transmission between different groups in the population. SFV strains formed two distinct clades within the SFV infecting the Cebidae family. This is the first study to use buccal swabs as a tool to study SFV diversity and prevalence in a recently free-living NP population upon recent capture. [ABSTRACT FROM AUTHOR]