Aricia Duarte-Benvenuto¹ | Ana Carolina Ewbank¹ | Roberta Zamana-Ramblas¹ | Irene Sacristán² | Samira Costa-Silva¹ | Vitor L. Carvalho³ | Daniela Magalhães Drummond de Mello⁴ | Vera Maria Ferreira da Silva⁴ | José Luiz Catão-Dias¹ | Carlos Sacristán ²

1. School of Veterinary Medicine and Animal Sciences – University of São Paulo, São Paulo, SP, Brazil; 2. Centro de Investigación en Sanidad Animal (CISA-INIA), CSIC, Valdeolmos, Spain; 3. Associação de Pesquisa e Preservação de Ecossistemas Aquáticos - AQUASIS, Caucaia, CE, Brazil; 4. Instituto Nacional de Pesquisas da Amazônia - INPA. Manaus, AM, Brazil.

Ponente: Aricia Duarte-Benvenuto, aricia.benvenuto@gmail.com

The family Trichechidae (order Sirenia) comprises three species: African (Trichechus senegalenses), West Indian (T. manatus) [Florida (T. m. latirostris) and Antillean (T. m. manatus, ATM)], and Amazonian manatees (T. inunguis, AMM). Whereas ATM inhabits riverine and coastal systems in the western Atlantic, AMM is the only exclusively freshwater sirenian, endemic to the Amazon River Basin. Studying infectious agents is essential to species conservation, especially in threatened species. The current knowledge about viral agents in sirenians is scarce. Herpesviruses and adenovirus are DNA viruses able to infect and cause disease in a wide host range. We used panPCR protocols to survey herpesvirus and adenovirus in blood samples of wild ATM (n = 23) and AMM (n = 26) under human care, Brazil. Herpesvirus DNA was detected in one juvenile female ATM (1/23; 4.3% prevalence; 95% CI -4.7 – 13.3) from Ceará and in four AMM (two juvenile females, a juvenile male, and an adult female; 4/26; 15.4% prevalence; 95% CI 0.5 – 30.3), from the Amazon. We obtained two different gammaherpesvirus DNA polymerase sequence types (one in ATM and one in three AMM), highly similar (99% nucleotide identity) to Trichechid herpesvirus 1, reported in Florida manatees (USA), and 100% identical when translated into amino acids. A gammaherpesviral glycoprotein B sequence was identified in two AMM. No samples were positive to adenovirus. To our knowledge, this is the first herpesvirus detection in manatees from South America, and in ATM and AMM worldwide. Our findings suggest (i) that West Indian and Amazonian manatees are likely the natural hosts of the detected herpesvirus, and (ii) herpesvirus ancestral adaptation based on the hypothetical Plio-Pleistocene origin and diversification of the genus Trichechus. Future studies are necessary to characterize this virus and potential pathological effects (if any) in these species.