Atypical Toxoplasma gondii genotype in feral cats from the Fernando de Noronha Island, northeastern Brazil.

Toxoplasma gondii isolates from Brazil have a different phenotypic and genotypic pattern, with predominance of virulent isolates and recombinant genotypes, compared to the North Hemisphere. Considering that a new T. gondii genotype, non-pathogenic to mice, was previously identified from free-range chickens from the Fernando de Noronha Island, Brazil, this study aimed to identify genotypes of this parasite in tissue samples of feral cats (Felis catus) from this Brazilian Island. Anti-T. gondii IgG antibodies were detected in 18/31 (58%) feral cats. Two non-virulent T. gondii isolates were obtained by mouse bioassay. Genotyping was performed by PCR-RFLP using 10 genetic markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, PK1, L358 and Apico) and an atypical strain of T. gondii (ToxoDB #146) was identified. This is the first report of this genotype in feral cats.

Vector Surveillance for Dengue Virus Detection in the Archipelago of Fernando de Noronha, Brazil.

Aedes aegypti (L.) has become an efficient vector of important arboviruses due to its anthropophilic and domiciliary behaviors. Since the 1980s, dengue affects thousands of people every year in Brazil; in Fernando de Noronha (FN), a touristic archipelago, dengue cases have occurred since 2001. Once Ae. aegypti populations are well established in the inhabited areas of FN, the threat of dengue or another arbovirus epidemic is continuously imminent. This study aimed to monitor the DENV serotypes in mosquito samples collected in FN, where at least one resident was clinically diagnosed as dengue patient. Entomological surveillance was conducted in 2011 and 2012. Mosquitoes were sorted by sex and location and were stored in pools. DENV detection was performed using polymerase chain reaction with reverse transcription (RT-PCR) and the Platelia Dengue NS1 Ag. RNA integrity was checked by RT-PCR using rpL8 primers, and the minimum infection rate (MIR) was calculated. In total, 339 pools were analyzed, and only one was positive (DENV-1) by Multiplex RT-PCR (MIR = 1.53). When considering only pools with RNA integrity, the MIR was 2.92. Using the Platelia kit, the MIR was 9.18 (considering all the pools) and 17.54 (only 140 pools with RNA integrity). Our results showed the importance of a constant entomological surveillance in that area, the need to improve storage and transportation protocols, and an endogenous control in the RT-PCR to avoid false-negative results. Finally, our study indicated that the NS1-Ag detection was the most sensitive method and should be used routinely for DENV surveillance in mosquitoes if the serotype identification is not required.

Seroprevalence of Toxoplasma gondii in domestic and wild animals from the Fernando de Noronha, Brazil.

Fernando de Noronha is an archipelago of 21 islands and islets in the Atlantic Ocean, state of Pernambuco, Brazil, which has a varied biodiversity including alien species or sinantropic animals. The objective here was to determine the seroprevalence of Toxoplasma gondii in domestic and wild animals from Fernando de Noronha archipelago, Brazil. Between July 2007 and May 2010, blood samples were collected from 764 animals (533 domestic and 231 wild animals). Sera were tested by the indirect fluorescence antibody test (IFAT) or the modified agglutination test (MAT), or by both. Antibodies to T. gondii were found in 80 (80.0%) of 100 chickens ( Gallus domesticus ), 3 (3.0%) of 100 cattle ( Bos taurus ), 59 (60.8%) of 97 sheep ( Ovis aries ), 9 (81.8%) of 11 goats ( Capra hircus ), 7 (43.7%) of 16 horses ( Equus caballus ), 70 (59.3%) of 118 cats ( Felis catus ), 36 (39.6%) of 91 dogs ( Canis familiaris ), 13 (38.2%) of 34 black rats ( Rattus rattus ), and 157 (79.7%) of 197 cattle egrets ( Bubulcus ibis ). Results indicate endemic infection by this zoonotic parasite among the animal and avian fauna in this archipelago from Brazil.