Epidemiology Investigation of Rodents as Vectors for the Hantavirus in Taiwan’s Harbor Areas

Jui-Wei Hsieh

2008 Vol.24 NO.1

Correspondence Author： Jui-Wei Hsieh

Abstract：

During the period from November 2004 to December 2006, a total of 1,446 rodents (52.49% males and 47.51% females) were captured in international and domestic harbors in Taiwan under the investigation of the rodent distribution and the positive antibody rate of the Hantavirus. The rodents can be categorized into 2 orders, 2 families, 4 genus, and 7 species. The Brown rat (Rattus norvegicus) takes up 58.44% of the entire captured number. Following are other kinds placed in percentage order: House shrew (Suncus murinus) 24.97%, Taiwan bandicoot rat (Bandicota indica) 6.92%, Buff-bellied rat (Rattus flavipectus) 6.36%, Brown country rat (Rattus losea) 2.14%, Black rat (Rattus rattus) 1.04%, and the House mouse (Mus musculus) 0.14%. Apart from the Taiwan bandicoot rat and Brown country rat found in Taoyuan Airport, Buff-bellied rat and House shrew found in the Kinmen area, and the Brown rat in Su-ao Harbor, the main population of rodents found in other harbor
areas is made up of Brown rats and House shrews. The captured number
did not differ greatly due to the different seasons. Categorizing by species, the Brown rat showed the highest positive antibody rate (18.82%). Following are Black rat, House shrew, and Buff-bellied rat with positive antibody rates of 6.67%, 6.37%, and 5.43%. The average positive antibody rate is 13.00%, which is slightly higher than results found in previous investigations. This shows that the Hantavirus is still prominent in Taiwan’s harbor areas and therefore cannot be ignored. In this investigation, results showed that the average positive antibody rate in domestic harbors is 20.48%. Although the rate for domestic harbors is higher than the rate for international harbors (11.45%), this does not mean that the rate is relatively higher in domestic harbors due to the widely dispersed rate results. With the exception of Taoyuan Airport and Hualien Harbor which showed a 0.00% rate, other international harbors had a rate between 3.16% and 25.64%. From high to low are Su-ao Harbor (25.64%), Kaohsiung Harbor (22.16%), Taichung Harbor (19.28%), Keelung Harbor (15.24%), Kaohsiung Airport (11.54%), Mailiao Harbor (6.38%), and Lienchiang (5.19%), and Kinmen (3.16%). In domestic harbors, the positive rate is between 11.86% and 56.25%. The highest is in Wu-ci Harbor with a 56.25%. The other harbors are as following from high to low: Shuei-di-liao Fishing Harbor (23.81%), Fang-liao Fishing Harbor (15.71%), Dong-gang Fishing Harbor (14.93%), and Ba-dou-zih Fishing Harbor (11.86%).
Key Words: Harbor, Hantavirus, Rodent, Positive Antibody Rate