E Tittarelli1,2, P R Barrero1,2, A S Mistchenko1,3, L E Valinotto1,2. 1. Laboratorio de Virología Hospital de Niños 'Ricardo Gutiérrez', Buenos Aires, Argentina. 2. Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina. 3. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires, Buenos Aires, Argentina.
Abstract
OBJECTIVES: To evaluate the occurrence of secondary dengue virus (DENV) infections during the 2009 outbreak in a non-endemic area. Viral loads were evaluated in serum from acute-phase patients, comparing primary and secondary infection. METHODS: Serum samples from patients with clinical diagnosis of suspected dengue were referred to the Virology Laboratory at 'Ricardo Gutiérrez' Children's Hospital. Dengue-positive samples were classified as primary or secondary DENV infections through serological methods (anti-DENV IgM and IgG). Viral loads were measured by quantitative real-time PCR (qRT-PCR) in samples obtained in the first 5 days of infection. Statistical analyses were performed to evaluate factors that might correlate with differences in the viral load of primary or secondary infection. RESULTS: A total of 229 DENV cases were confirmed; among them, 22.7% were secondary infections. No significant differences were found between the viral load of primary and secondary infections. CONCLUSION: We detected a high percentage of secondary DENV infections in a non-endemic area; this finding might correspond to socio-demographic characteristics of the group under study or indicate a previous cryptic DENV circulation causing inapparent infections.
OBJECTIVES: To evaluate the occurrence of secondary dengue virus (DENV) infections during the 2009 outbreak in a non-endemic area. Viral loads were evaluated in serum from acute-phase patients, comparing primary and secondary infection. METHODS: Serum samples from patients with clinical diagnosis of suspected dengue were referred to the Virology Laboratory at 'Ricardo Gutiérrez' Children's Hospital. Dengue-positive samples were classified as primary or secondary DENV infections through serological methods (anti-DENV IgM and IgG). Viral loads were measured by quantitative real-time PCR (qRT-PCR) in samples obtained in the first 5 days of infection. Statistical analyses were performed to evaluate factors that might correlate with differences in the viral load of primary or secondary infection. RESULTS: A total of 229 DENV cases were confirmed; among them, 22.7% were secondary infections. No significant differences were found between the viral load of primary and secondary infections. CONCLUSION: We detected a high percentage of secondary DENV infections in a non-endemic area; this finding might correspond to socio-demographic characteristics of the group under study or indicate a previous cryptic DENV circulation causing inapparent infections.
Authors: Estefanía Tittarelli; Silvina B Lusso; Stephanie Goya; Gabriel L Rojo; Mónica I Natale; Mariana Viegas; Alicia S Mistchenko; Laura E Valinotto Journal: Emerg Infect Dis Date: 2017-10 Impact factor: 6.883