Seroprevalence survey of Toscana virus infection in Oporto region.

Abstract

Toscana virus (TOSV) endemic in central Italy, has been documented in several European countries of the Mediterranean region. It is a neurotropic virus and in some of these countries studies to investigate seroprevalence have been done. In a recent etiologic study of meningitis we chose 106 of 308 samples to be tested for TOSV using a nested RT-PCR assay, and found six (5.6%) cases of meningitis by Toscana virus.To investigate the seroprevalence of antibodies against TOSV in a cohort of a population attended in our Hospital.In serum samples collected for routine study we have investigated the presence of antibodies for TOSV. The study included samples of patients hospitalized and others observed in ambulatory and includes children and adults. Immunocompromised patients were excluded. The test was based on the-ELISA technique ((ENZYWELL), according to the manufacture instructions, being positive for a cut-off>1.2, negative if the cut-off <0.8 and doubtful if the cut-off >0.8 e <1.2.334 serum samples arbitrarily were used for seroprevalence study of antibodies to TOSV, 304 adults and 30 children. Positive results for anti-TOSV were obtained in 13 (3.9%) samples; in other 21 the result was doubtful and in those cases it was not possible to repeat because we have only one pair of serum and in the remaining 300 the result was negative. The positive samples were all from adults, 8 females and 5 males, 8 (62%) of them were older than 60 years. All children' samples were negative for TOSV antibodies.We documented a seroprevalence of 3.9% to TOSV, namely in adults older than 60 years. Our prevalence is lower when compared to other European countries, namely Spain (5-22%).