Survey on infectious status of leptospira in rats of Fujian Province

Objective To study the densit, species, infection rate and distribution of Leptosira of the host animals in Fujian Province, so as to provide a scientific basis for prevention and control of Leptospirosis. Methods From 2011 to 2016, fourteen areas were selected according to the epidemic of leptospirosis in Fujian. Rats were captured with squirrel-cage method and their sera and organs were collected for pathogen culture and detection of antibody. Results A total of 1 312 rats were captured, whose rat density rate was 6.29%. And the rat density rates of 14 areas ranged from 3.25% (middle part of Fujian) to 9.98% (eastern part of Fujian). The Rattus losea, R.flavipectus, R. norvegicus and Niviventer fulvescens accounted for 87.57% of total rats. The distribution of rat species varied from area to area. Ten strains of Leptospira were isolated from the rat samples. The rat serum antibody positive rate was 26.42%, among which the Autumnalis and Java were major Leptosira (73.50%). Rat infection rates varied from area to area, ranged from 15.56% (middle part of Fujian) to 45.00%(northern part of Fujian). The highest infection rate of Leptospira were detected in R. flavipectus (35.53%), R. bowersi(31.58%) and Rattus losea (27.57%) respectively. Conclusions The distribution of rat species in Fujian was complex, and the dominant species were Rattus losea, R. flavipectus, R. norvegicus and Niviventer fulvescens. The infection level of rats was high, and the distribution of rat species and infection rate varied from area to area.