The aim of this experiment was to study enzyme activity of superoxide dismutase(SOD) in Haemaphysalis longicornis ticks and its change over time after Bartonella henselae had been inoculated into them.First,five microlitres of B.henselae suspension(105cfu/μL) were injected into the hemocoelic cavity of partially fed virgin female H.longicornis using a 10 μL Hamilton syringe.Then hemolymph samples were collected at 1 h,6 h,12 h,24 h and 48 h after inoculation.Finally,the activity of SOD was determined with the SOD detection kit manufactured by Jiancheng,Nanjing.The method was also repeated by using saline solution as control.The enzyme activity of SOD remained steady for 48 h in infected group.Whereas the control group,the enzyme activity peaked at 12 h(11.1 999±1.3 248U/mL) and higher than infected group,there was a difference between the two groups at 12 h(P=0.036);then the activity decreased at 48 h,and lower than that at 1 h(P=0.000).The result showed that the enzyme activity of SOD would be inhibited when H.longicornis was attacked by B.henselae in a certain period,which suggests that the B.henselae stress might be a suppression factor with the enzyme activity of SOD over time or concentration.

Objective To evaluate the effects of different vector mosquito control measures for malaria in Yongcheng through field tests.Methods Vector monitoring was conducted in villages using different vector prevention and control measures,where mosquitoes of anopheles were captured every ten days using 50 mosquito nets indoors in early morning and using human baits outdoors at night.Results A total of 79 anopheles mosquitoes were captured by nets in early morning,accounting for 33.33%,with other captives of 158 accounting for 66.67%.The average anopheles density was 0.18/net per capture in the control group,and 0.03,0.03,0.05 and 0.06/net per capture in the impregnated-net group,residual spraying group,impregnated-net plus larviciding group and residual spraying plus larviciding group,respectively.Albeit effective in reducing anopheles density(F=4.553,P0.01),these measures were not deemed different in the effects.The average man-biting rate was 0.10 mosquito/(person·night) in the control group,and 0.02,0.01,0.03 and 0.03 mosquito/(person·night) in the impregnated-net,residual spraying,impregnated-net plus biological larviciding and residual spraying plus larviciding groups,respectively.Though effective in reducing man-biting rates(F=5.261,P0.01),the measures were not considered different in the effects.At different monitoring sites,183 anopheles mosquitoes were captured outdoors by human baits at night,accounting for 15.69%,with other captives of 983 accounting for 84.31%.The average anopheles density was 2.48/h in the control group,and 0.76,2.12,0.24,1.08 and 0.64/h in the impregnated-net,residual spraying,biological larviciding,impregnated-net plus larviciding and residual spraying plus larviciding groups,respectively.The mosquito density in the impregnated-net,biological larviciding,impregnated-net plus larviciding and residual spraying plus larviciding groups was lower than that in the control group,and the density in the residual spraying group was higher than those in the impregnated-net,biological larviciding and residual spraying plus larviciding groups.The average man-biting rate was 12.40 mosquitoes/(person·night) in the control group,and 3.80,10.60,1.20,5.40 and 3.20 mosquitoes/(person·night) in the impregnated-net,residual spraying,biological larviciding,impregnated-net plus larviciding and residual spraying plus larviciding groups,respectively.The man-biting rates in the impregnated-net,biological larviciding,impregnated-net plus larviciding and residual spraying plus larviciding groups were lower than that in the control group,while the rate in the residual spraying group was higher than those in the impregnated net,biological larviciding and impregnated-net plus larviciding groups.The Pearson correlation analysis revealed a positive correlation between the outdoor anopheles density in October and the incidence of malaria in November(r=0.945,P0.01),and a positive correlation between the corrected man-biting rate in October and the incidence of malaria in November(r=0.927,P0.05).Conclusion The above prevention and control measures were effective in reducing both indoor and outdoor anopheles density as well as man-biting rates in Yongcheng city;however,the advantages and disadvantages of specific measure should be further studied.