First Dengue Outbreak in Cordoba: Response to the Epidemic by Central Laboratory of Cordoba.

CASTRO G; BARBÁS G; BORDA M; GALLEGO S; FREGA L; BLANCO S; FABRI C; LUPPO V; MORALES A; KADEMIÁN S; DE LEÓN J; CUDOLÁ A

Simposio; III International Clinical Virology Symposium and Advances in Vaccines; 2010

CEMIC

Background: On March 2009 the local spread of DEN-1 virus was reported in some provinces of Argentina. On April 2009, new molecular techniques for diagnosis and early typifying of the virus were implemented at the Central Laboratory of Cordoba (reference laboratory for the diagnosis of Dengue virus). The aim of the present study is communicate our experience during the first dengue outbreak in Cordoba. Materials and Methods: Between April 20th and June 11th 2009, a total of 1902 blood samples, with presumptive Dengue diagnosis were derived to the Central Laboratory from different public hospitals of Cordoba. Early samples (patients with up to 3 days of clinical evolution) were studied by in house RT-PCR, following Lanciotti?s protocol (Journal of clinical microbiology 1992), whereas in samples from patients with over 3 days of clinical evolution the presence of IgM anti-Dengue by UM ELISA was investigated. For negative samples by RT-PCR or ELISA, and less than 7 days of clinical evolution, a later second sample for IgM anti-Dengue detection to confirm or rule out infection was required. In Agreement with the National Laboratories Network for Dengue and others Arbovirus (NLN), reactive samples and 10% of negative were sent, as a quality control strategy and for studying the presence of other flavivirus. Results: Of the 1902 studied samples, 1646 corresponded to late samples and 246 were early samples. From these samples, 19.4% (319/1646) was reactive for IgM anti-Dengue and 10.6% (26/246) resulted positive by RT-PCR. All the positive samples by RT-PCR corresponded to DEN-1 genotype. It was achieved an excellent concordance between our results and those obtained by the NLN using molecular assays. Moreover, 80% of the IgM reactive samples derivated were confirmed as Dengue cases by means of serological methods. From the 659 second samples requested, 329 were not defined because these patients did not return for a new control. Conclusions: During the Dengue?s outbreak, at the Central Laboratory of Cordoba the diagnosis algorithm was modified in accordance to the NLN guidelines, giving a rapid and adequate response to the sanitary emergency. Thus, Cordoba?s Ministry of Health was able to carry out the timely prevention and control of the epidemic, optimizing resources.