Figure 6. Number of reported cases due to dengue disease, by month, Thailand, 2000–2012 [23]–[34].

Most of Thailand has a tropical wet and dry or savannah climate, where the wettest months are usually August–October. Country-wide, average annual temperatures range from 19°C to 38°C, with higher temperatures in the dry season (November to March). The available data show a seasonal peak in the numbers of cases due to dengue between May and September reflecting seasonal changes in climate and the association between the wettest months and vector activity.