Influenza like illness in adult outpatients in Argentina: The importance of respiratory viruses including human metapneumovirus.

CECILIA SANTAMARÍA 1*, ANALÍA URUEÑA 2, MARCELA ECHAVARRÍA 3, CRISTINA VIDELA 3, ANDREA PERROT 4, ARIEL SUAREZ 3, CECILIA GANDUGLIA 4, BEATRIZ EBEKIAN 3, CARMEN RICARTE 3, JOSÉ USTARÁN 4, GUADALUPE CARBALLAL 3 AND PABLO BONVEHI 1.

EUROPEAN JOURNAL OF EPIDEMIOLOGY

Año: 2006

0393-2990

Influenza like illness in adult outpatients in Argentina: The importance of respiratory viruses including human metapneumovirus. Cecilia Santamaría 1*, Analía Urueña 2, Marcela Echavarría 3, Cristina Videla 3, Andrea Perrot 4, Ariel Suarez 3, Cecilia Ganduglia 4, Beatriz Ebekian 3, Carmen Ricarte 3, José Ustarán 4, Guadalupe Carballal 3 and Pablo Bonvehi 1. Abstract Influenza virus is the most common cause of influenza-like illness in adults worldwide. Surveillance studies have been done most frequently in developed countries, but data  from Argentina come mainly from pediatric populations. The purposes of this study were: i) to determine the frequency of influenza A, influenza B, respiratory syncytial virus, adenovirus, parainfluenza viruses and human metapneumovirus in nasal and throat swabs from adult outpatients with influenza-like illness during the winter of 2004 and 2005 by immunofluorescence, culture or RT PCR, ii) to evaluate circulation of influenza strains in the community iii)  to determine whether the signs and symptoms predicted vial etiology and, iv) to evaluate the utility of viral detection methods to change clinical management and install infection control measures. Of 151 samples analyzed by immunofluorescence,  39 (26%) were influenza A positive,  5 (3.3%) were influenza B positive, 4 (2.6%) were respiratory syncytial virus positive, and 2 (1.3%) were human metapneumovirus positive by RT PCR.  Cell culture detected 3 additional influenza A, 3 influenza B and 1 adenovirus positive samples. The sensitivity of immunofluorescence for influenza compared to cell culture was 70%. None of the symptoms was significantly associated with a positive or negative viral result. In this study 40 % of the patients with influenza like illness were associated to a specific viral infection. Viral detection was useful in order to implement infection control measures including segregation of infected individuals. Circulating influenza strains were closely related to 2004 and 2005 vaccine strains.