Relationship between falciparum malaria incidence and the number of Anopheles dirus in Hainan from 2001 to 2008

Objective: To analyze the relationship between falciparum malaria incidence and the number of Anopheles dirus in Hainan Province from 2001 to 2008, so as to provide the evidence for malaria control and prevention in Hainan Province.

Methods: The falciparum malaria incidence and the numbers of Anopheles dirus in 2001 - 2008 were calculated according to the data from Wuzhishan City and Qiongzhong County in Hainan Province. The Cochran-Armitage trend test was employed to explore the trend of falciparum malaria incidence. And Spearman rank correlation analysis was applied to analyze the relationship between the falciparum malaria incidence and the numbers of Anopheles dirus in Hainan from 2001 to 2008.

Results: A fluctuating but distinctly declining temporal trend of falciparum malaria incidence was identified in these two areas (Z(Wuzhishan) = -6.16, P < 0.01; Z(Qionghong) = -7.17, P < 0.01). The falciparum malaria incidences were not correlated with the numbers of Anopheles dirus in these two areas (r(wuzhishan) = 0.36, P > 0.05; r(Qiongzhong) = 0.67, P > 0.05).

Conclusions: The control and prevention of falciparum malaria should be implemented from many aspects, as well as Anopheles dirus control, environment management, susceptible people protection and so on.