Abstract
Japanese encephalitis (JE) is one of the most important mosquito-borne viral diseases in Asia. Pigs are a natural host and the amplifier of JE virus. The sero-conversion rate to JE virus in sentinel pigs reflects the activity of JE virus in the region. We analyzed whether precipitation has any effect on the sero-conversion rate to JE virus in sentinel pigs. Linear regression analysis was performed to determine the correlations between the levels of precipitation and sero-conversion rates to JE virus, in the entire year and during summertime over the period of 32 years from 1969 to 2000. The levels of the annual and summertime precipitation demonstrated statistically significant positive correlations with sero-conversion rates for the whole of the country and for some regions in Japan. The levels of the summertime precipitation, on the other hand, demonstrated statistically significant inverse correlations with the sero-conversion rates in other regions. Further, the levels of precipitation during preceding 10-day periods from days 1–40 before blood collection showed inverse correlation with antibody-positive rates in some regions. The results indicate that the relationship between the annual and summertime precipitation, and the sero-conversion rate to JE virus is complex; both positive and inverse effects are demonstrated depending on the regions.
Highlights
Climate change affects various aspects of human health, including infectious diseases
We have reported that temperature has positive effect on sero-conversion rates to Japanese encephalitis (JE) virus in sentinel pigs (Kurane et al, submitted manuscript)
The results suggest that the relationship between the annual and summertime precipitation, and the sero-conversion rate to JE virus is complex; there were statistically significant positive correlations in the whole of country and in some of the regions; and there were statistically significant inverse correlation in other regions
Summary
Climate change affects various aspects of human health, including infectious diseases. Vector-borne infectious diseases and water-borne infectious diseases are two main categories of infectious diseases that are forecasted to be most affected [1,2,3]. The levels of the effects and the mechanisms have not been fully understood [4,5,6]. The levels and types of the effects on the same infectious disease may be different, depending on the geographical location and the socio-economic status. Japanese encephalitis (JE) is a mosquito-borne viral encephalitis with a high mortality rate and a high percentage of neuro-psychiatric sequelae [7]. JE occurs endemically and/or epidemically in many
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
