[The tendency of prevalence of hypertension in two countries in Gansu province from 1990 to 2012].

OBJECTIVE: To study the variation tendency of hypertension in two rural areas in Gansu, and provide epidemiological evidence to evaluate the hypertension of rural residents. METHODS: Using equidistant random sampling method and cross-sectional sentinel monitoring, two remote natural villages, Yangzhuang and Xiangming, at Yellow river and Yangtze river valley were selected as hypertension monitoring site. From 1990 to 2012, clinical examination to the resident above 18 years old was carried out continuously for 23 years, 11 164 cases were included. RESULTS: Hypertension prevalence of tested cases increased with years, Yangzhuang monitoring site increased from 6.9% (16/232) in 1990 to 36.7% (216/597) in 2012 with an increase of 29.8%, and Xiangming monitoring site increased from 3.4% (16/474) in 1995 to 20.6% (120/582) in 2011 with an increase of 17.2%. Total prevalence of Yangzhuang (24.1%, 1505/6240) was significantly higher than Xiangming (11.4%, 578/4924) (χ(2) = 277.9, P < 0.01). Total hypertension prevalence of 18 - 35 years old group was 9.9% (292/2944) in Yangzhuang and 4.2% (63/1495) in Xiangming, Yangzhuang was higher than Xiangming (χ(2) = 43.7, P < 0.01). Total hypertension prevalence of above 35 years old group was 36.8% (1213/3296) in Yangzhuang and 14.1% (515/3429) in Xiangming, Yangzhuang was higher than Xiangming (χ(2) = 417.7, P < 0.01). The growth rates of hypertension prevalence in 18 - 35 years old group of both areas (Yangzhuang: 823.5%, Xiangming: 614.3%) were higher than 35 years old group (Yangzhuang:310.5%, Xiangming: 368.0%), but the hypertension prevalence of above 35 years old group was higher than 18 - 35 years old group. Hypertension prevalence of male was 25.4% (761/2992) in Yangzhuang and 11.7% (238/2047) in Xiangming, Yangzhuang was higher than Xiangming (χ(2) = 145.8, P < 0.01), hypertension prevalence of female was 22.7% (738/3248) in Yangzhuang and 11.2% (340/2877)in Xiangming, Yangzhuang was higher than Xiangming (χ(2) = 125.1, P < 0.01). While the difference between male and female had no statistical significance in both areas. CONCLUSION: Hypertension of the two monitoring points was in high epidemic trend, but with different epidemic trend. From different region and environment research to discuss the cause of hypertension can provide scientific evidence for prevention and control.

[Preliminary test of phlebotomus surveillance by light-traps].

Different light-traps were tested in Wenxian of Gansu Province, including the light-traps without lamp and with glucose solution as attractant. Results showed that the light-traps attracted more mosquitoes and other insects than sandflies, and it became difficult to pick up the sandflies from gathering packet; the light-trap without lamp captured smaller amount of sandflies but much less other insects; glucose showed no significant effect in attracting sandflies. The existing light-traps are not so effective for Phlebotomus surveillance, and it is suggested that more effective attractants be tried.

[Asymptomatic Leishmania infection in human population of Wenxian County, Gansu Province].

OBJECTIVE: To analyze the status of Leishmania infantum asymptomatic infection in human population of a Kala-azar endemic area in Wenxian County, Gansu Province, and to evaluate the tests used. METHODS: Blood samples were tested by PCR using two pairs of primers, RV1-RV2 and K13A-K13B, for detecting Leishmania-specific DNA. ELISA and rK39-dipstick were used to detect Leishmania-specific antibodies. RESULTS: The positive rate of PCR, ELISA and rK39-dipstick was 30.9%(83/269). 24.2%(65/269) and 0 (0/269) respectively. CONCLUSION: The prevalence of asymptomatic infection of L. infantum in humans is high in the area. PCR test based on RV1-RV2 and K13A-K13B primer pairs is a sensitive and specific method for detecting the asymptomatic infection.