摘要
From 1950 to 2019,a total of 267 plague cases in humans were reported in the Inner Mongolia Autonomous Region with 133 deaths and 10,710 Yersinia pestis isolates;21 of these cases were reported from the Meriones unguiculatus(M.unguiculatus)plague focus with 6 deaths and 6,771 isolates.According to the plague situation in the Inner Mongolia Autonomous Region and the implementation of local preventive measures,the prevalence of plague in humans in the M.unguiculatus plague focus of the Inner Mongolia Autonomous Region could be divided into four stages.The first stage was the initial stage of plague prevention and control(1950–1959),with 0.80 cases annually and a case fatality rate of 37.50%.The second stage was the plague eradication stage(1960–1979),with 0.15 cases annually and a case fatality rate of 33.33%.The third stage was the plague surveillance stage(1980-1999),with 0.25 cases annually and a case fatality rate of 20.00%.The fourth stage is the comprehensive prevention and control stage under the emergency system(2000-2019),with 0.25 cases annually and a case fatality rate of 20.00%.The surveillance of rodent density(1981-2019)and studies on plague-related factors among M.unguiculatus have shown that the higher the M.unguiculatus density,the higher the nocturnal rodent capture rate(r=0.670,p<0.05)and the higher the indirect hemagglutination assay(IHA)positive rate of M.unguiculatus(r=0.344,p<0.05);the higher the percentage of hosts infected,the lower the M.unguiculatus density(r=-0.361,p<0.05)and the lower the IHA positive rate of M.unguiculatus(r=-0.337,p<0.05);the higher the percentage of nests infected with fleas,the lower the IHA positive rate of M.unguiculatus(r=-0.348,p<0.05).Together,these results suggest that it is necessary to simultaneously monitor the pathogens,serology,and vector index of M.unguiculatus to accurately reflect the plague prevalence among local animals.Although bubonic plague is the main plague type of the M.unguiculatus plague focus,severe pneumonic plague or septic plague may be secondary when the bubonic plague is misdiagnosed or not treated in time.In addition,the plague in animals is relatively virulent in the M.unguiculatus plague focus,and the risk of spreading to humans is higher.For plague in the Inner Mongolia Autonomous Region,comprehensive control efforts should be aimed at the M.unguiculatus focus,covering host animals,vector insects,and humans.
基金
supported by National Major Science and Technology Projects of China(2018ZX10713-003-002,2018ZX10713-001-002).
