Outbreak of acute respiratory infection among infants in Lisbon, Portugal, caused by human adenovirus serotype 3 and a new 7/3 recombinant strain

• Main Author: Rebelo-de-Andrade, H
• Publication Date: 2010
• Other Authors: Pereira, C, Gíria, M, Prudêncio, E, Brito, MJ, Calé, E, Taveira, N
• Format: Article
• Language: eng
• Source: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Download full: http://hdl.handle.net/10400.10/415
• topic: Infecções por adenovirus; Criança; Adenovirus humano; Infecções respiratórias; Portugal; Respiratory infection; Human adenovirus

Human adenoviruses (AdVs) typically cause mild illnesses in otherwise healthy hosts. We investigated a pediatric outbreak of acute respiratory infection with fatal outcomes that occurred in Lisbon, Portugal, in 2004. Biological specimens were collected from 83 children attending two nurseries, a kinesiotherapy clinic, and the household of a nanny. Adenovirus infection was confirmed in 48 children by PCR and virus isolation. Most (96%) isolates were classified as being of subspecies B1. Phylogenetic analysis of fiber and hexon gene sequences revealed that most infants were infected with AdV serotype 3 (AdV3) strains. Infants attending one nursery harbored a new recombinant strain containing an AdV serotype 7 hexon and serotype 3 fiber (AdV7/3). Both the AdV3 and the AdV7/3 strains caused fatal infections. Two different serotype 3 strains were circulating in Lisbon in 2004, and the new AdV7/3 recombinant type originated from only one of those strains. These results demonstrate that recombination leads to the emergence of new adenovirus strains with epidemic and lethal potential.