【摘 要】
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Three behaviors of epidemiological importance,namely feeding latency,feed-ing duration and defecation latency,for six populations of Meccus phyllosomus longipen-nis(Usinger)from areas of central,western and north-central Mexico with high(HP)and low(LP)pre
【机 构】
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Laboratorio de Entomología Médica,Centro Universitario del Sur Universidad de Guadalajara,Ciudad Guz
论文部分内容阅读
Three behaviors of epidemiological importance,namely feeding latency,feed-ing duration and defecation latency,for six populations of Meccus phyllosomus longipen-nis(Usinger)from areas of central,western and north-central Mexico with high(HP)and low(LP)prevalence of Trypanosoma cruzi(Chagas)human infection were evaluated in this study.The median feeding latency(the time taken to begin feeding)was highly variable between instars.Within-instar comparisons showed that at least 65％of the LP populations(N3 to adult)started to feed significantly(P＜0.05)later than the HP popu-lation,with N1 showing no difference,and N2 from LP populations feeding sooner than those from HP populations.The six populations had similar median feeding durations within instars.A higher(P＜0.05)percentage of the instars from HP populations defe-cated faster than the respective instars from the three LP populations.Approximately 25％of the young nymphs(N1 to N3)and females in the HP populations defecated＜2 min postfeeding,compared with 4％-6％of the young nymphs and 1.3％-3％of females in the LP populations.Moreover,17.7％-38.8％of the older nymphs(N4 to N5)in the HP populations and 6.8％-13.4％in the LP populations defecated during or immediately af-ter feeding.Our results indicate that the HP populations have a greater potential than the LP populations to transmit T.cruzi infections,which may underlie the differences in the prevalence of T cruzi infection in some areas where M.p.longipennis is currently dis-tributed.
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