Change in Dengue and Japanese Encephalitis Seroprevalence Rates in Sri Lanka

Abstract

BackgroundSri Lanka has been affected by epidemics of dengue infections for many decades and the incidence and severity of dengue infections have been rising each year. Therefore, we investigated the age stratified seroprevalence of dengue infections in order to facilitate future dengue vaccine strategies. In addition, since the symptomatic dengue infections have increased during the past few decades, we also investigated the possible association with Japanese Encephalitis Virus (JEV) antibody seropositivity with symptomatic dengue in a community cohort in Sri Lanka.Methods1689 healthy individuals who were attending a primary health care facility were recruited. Dengue and JEV antibody status was determined in all individuals and JEV vaccination status was recorded.Results1152/1689 (68.2%) individuals were seropositive for dengue and only 133/1152 (11.5%) of them had been hospitalized to due to dengue. A significant and positive correlation was observed for dengue antibody seropositivity and age in children (Spearmans R = 0.84, p = 0.002) and in adults (Spearmans R = 0.96, p = 0.004). We observed a significant rise in the age stratified seroprevalence rates in children over a period of 12 years. For instance, in year 2003 the annual seroconversion rate was 1.5% per annum, which had risen to 3.79% per annum by 2014. We also found that both adults (p<0.001) and in children (p = 0.03) who were hospitalized due to dengue were more likely to be seropositive for JEV antibodies. However, 244 (91.4%) of adults who were seropositive for JEV had not had the JEV vaccine.ConclusionsDengue seroprevalence rates have risen significantly over the last 12 years in Sri Lanka, possibly due to increased transmission. As individuals who were hospitalized due to dengue were more likely to be seropositive for JEV, the possibility of cross-reactive assays and/or of JEV infection on immunity to the DENV and clinical disease severity should be further investigated.

Dengue or Japanese encephalitis?

“…It was noted that antibodies for JE virus were associated with increased prevalence of symptomatic dengue infection [9]. A recent study noted that patients who were admitted for dengue virus infection, also turned out to be seropositive for JE [10].…”

Serological evidence for localized and persistent antibody response in Zika virus-positive neonates with microcephaly (Brazil, 2015)- a secondary analysis

“…Complex dynamics between serological assays for flaviviruses have been reported at the population level in other settings e.g. 7 and greater understanding and quantification of these trends may inform both ZIKV neuropathology studies and serological surveillance in areas with multiple co-circulating arboviruses.…”

A Systematic Review: Prevention of Japanese encephalitis in Asia

“…Sri Lanka Jeewandara C, et al (2015) [29] In Sri Lanka, immunization against JEV began gradually, and since 1988 it has been included in the national routine immunization program. JE vaccine recommends for travelers who will stay for more than one month in endemic areas during the JE virus transmission period.…”