Malaria surveillance-response strategies in different transmission zones of the People's Republic of China : preparing for climate change

ABSTRACT: BACKGROUND: A sound understanding of malaria transmission patterns in the People's Republic of China (P.R. China) is crucial for designing effective surveillance-response strategies that can guide the national malaria elimination programme (NMEP). Using an established biology-driven model, it is expected to design and refine appropriate surveillance-response strategies for different transmission zones, and thus assist in optimizing the NMEP in the ongoing implementation (2010--2020) and, potentially, in the post-elimination stage (2020--2050). METHODS: Environmental data obtained from 676 locations across P.R. China, such as monthly temperature and yearly relative humidity (YRH), for the period 1961--2000 were prepared. Smoothed surface maps of the number of months suitable for parasite survival derived from monthly mean temperature and YRH were generated. For each decade, the final malaria prediction map was overlaid by two mask maps, in terms of number of months suitable for parasite survival and YRH map in excess of 60%. RESULTS: Considering multiple environmental factors simultaneously, the regions suitable for malaria transmission were found to have shifted northwards, which was especially pronounced in northern P.R. China. The unstable transmission regions (transmission period between five and six months) increased transmission intensity due to prolonged transmission periods, especially in the central part of the country. CONCLUSION: Adequate and effective surveillance-response strategies for NMEP must be designed to achieve the goal of malaria elimination in P.R. China by 2020, especially in the zones predicted to be most vulnerable to climate change