A survey of zoonotic pathogens carried by Norway rats in Baltimore, Maryland, USA

Abstract

SUMMARYNorway rats (Rattus norvegicus) carry several zoonotic pathogens and because rats and humans live in close proximity in urban environments, there exists potential for transmission. To identify zoonotic agents carried by rats in Baltimore, Maryland, USA, we live-trapped 201 rats during 2005–2006 and screened them for a panel of viruses, bacteria, and parasites. Antibodies against Seoul virus (57·7%), hepatitis E virus (HEV, 73·5%),Leptospira interrogans(65·3%),Bartonella elizabethae(34·1%), andRickettsia typhi(7·0%) were detected in Norway rats. Endoparasites, includingCalodium hepatica(87·9%) andHymenolepissp. (34·4%), and ectoparasites (13·9%, primarilyLaelaps echidninus) also were present. The risk of human exposure to these pathogens is a significant public health concern. Because these pathogens cause non-specific and often self-limiting symptoms in humans, infection in human populations is probably underdiagnosed.