Monthly distribution and frequency of E30 and JEV cases. There were 43 confirmed E30 cases from NHP during 2001–2002 and 60 JEV confirmed cases from BGGH during 1999–2008. The E30 cases and the JEV cases were totaled separately according to the month and regardless of the year of occurrence. The total number of cases per month from January to December was plotted in the graph. The peak for both cases was from May to July.