Patterns of dengue virus IgM and IgG antibodies in suspected cases of dengue in Jamaica, 2003-2006.

The patterns of dengue immunoglobulin (Ig) M and IgG antibodies in patients presenting with dengue-like illnesses during 2003-2006 were investigated using enzyme linked immunosorbent assays (ELISA). The seroprevalence of dengue antibodies, dengue IgM and dengue IgG antibodies were 59.4% (979/1647), 15.4% (254/1647) and 51.1% (841/1647), respectively. A statistically significantly increasing trend in the prevalence of dengue IgG antibodies with age was observed, ranging from 38.4% in patients aged less than 1 year to 90% in those 60 of years and over (p = 0.000; 95% confidence interval (CI) = 0.000-0.002). Conversely the seroprevalence of dengue IgM did not differ significantly with age and no seasonality in the number of cases was observed. The patterns of IgM and IgG antibodies found in the present study are consistent with those found in dengue endemic countries during inter-epidemic periods indicating that an increasing risk of a new dengue outbreak due to the accumulation of susceptible population. Preventive measures should be maintained to control the endemic spread and reduce the risk of outbreaks of dengue in Jamaica. The high seroprevalence rate of dengue IgG antibodies might have implications for the emergence of the more severe forms dengue infection in the Jamaican population.