Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a “flip-flop” phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites.

No abstract

No abstract

No abstract

ABSTRACT:Serum samples from 18 pumas (Puma concolor), one ocelot (Leopardus pardalis), and two little spotted cats (Leopardus tigrinus) collected from free-ranging animals in Brazil between 1998 and 2004 were tested by indirect immunofluorescence (IFA) for antibodies to feline herpesvirus 1 (FHV 1), calicivirus (FCV), coronavirus (FCoV), parvovirus (FPV), Ehrlichia canis, Anaplasma phagocytophilum, and Bartonella henselae. Serum samples also were tested, by Western blot and ELISA, for feline leukemia virus (FeLV) specific antibodies and antigen, respectively, by Western blot for antibodies to feline immunodeficiency virus (FIV), and by indirect ELISA for antibodies to puma lentivirus (PLV). Antibodies to FHV 1, FCV, FCoV, FPV, FeLV, FIV, PLV or related viruses, and to B. henselae were detected. Furthermore, high-titered antibodies to E. canis or a closely related agent were detected in a puma for the first time.

Dengue epidemics have been reported in Brazil since 1985. The scenery has worsened in the last decade because several serotypes are circulating and producing a hyper-endemic situation, with an increase of DHF/DSS cases as well as the number of fatalities. Herein, we report dengue virus surveillance in mosquitoes using a Flavivirus genus-specific RT-Hemi-Nested-PCR assay. The mosquitoes (Culicidae, n = 1700) collected in the Northeast, Southeast and South of Brazil, between 1999 and 2005, were grouped into 154 pools. Putative genomes of DENV-1, -2 and -3 were detected in 6 mosquito pools (3.8%). One amplicon of putative DENV-1 was detected in a pool of Haemagogus leucocelaenus suggesting that this virus could be involved in a sylvatic cycle. DENV-3 was found infecting 3 pools of larvae of Aedes albopictus and the nucleotide sequence of one of these viruses was identified as DENV-3 of genotype III, phylogenetically related to other DENV-3 isolated in Brazil. This is the first report of a nucleotide sequence of DENV-3 from larvae of Aedes albopictus.

In a study of acute respiratory disease, two collections of nasopharyngeal aspirates (NPA) were obtained from children hospitalized at the Pediatric Clinic of the University Hospital, São Paulo, in 1995 and 2000. Adenovirus was detected in 33 (8.2%) of 401 children followed. These viruses were isolated in HEp-2, HEK-293, or NCI-H292 cells and serotyped by neutralization. The genome types were determined after restriction analyses of the genomic DNA extracted from infected cells. Nineteen isolates were characterized as Human adenovirus B, genome types HAdV-3a, HAdV-7h, and HAdV-7h1; 11 as Human adenovirus C, genome types HAdV-1D10, HAdV-2D25, HAdV-5D2, and HAdV-6D3. Our findings show that species C adenoviruses present an endemic infection pattern, with co-circulation of different serotypes and genome types; no new genomic variant was observed. Species B adenoviruses showed epidemic infection patterns, with shifts in the predominant genome type. The isolates from 1995 belong to genome type 7h, or the variant 7h1, with a clear substitution of the type 7b, prevalent in São Paulo for more then 10 years. In 2000, the variant 7h1 predominated and the emergence of the type 3a was observed. Almost 10 years passed between the identification of HAdV-7h in Argentina and its detection in São Paulo. The geographic isolation of these two countries was reduced by the increase in population mobility due to growing commercial relationships.

Rabies viruses circulating in Ceará, Brazil, were identified by molecular analysis to be related to variants maintained by dogs, bats, and other wildlife. Most of these viruses are associated with human rabies cases. We document the emergence of a rabies virus variant responsible for an independent epidemic cycle in the crab-eating fox (Cerdocyon thous).