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

Abstract

Norway 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%), and Rickettsia typhi (7.0%) were detected in Norway rats. Endoparasites, including Calodium hepatica (87.9%) and Hymenolepis sp. (34.4%), and ectoparasites (13.9%, primarily Laelaps 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.

Serosurvey of Leptospira spp. and Toxoplasma gondii in rats captured from two zoos in Southern Brazil

“…The frequency of seropositive rats in both zoos was lower than that previously described in Baltimore (32%) 12 , Copenhagen (94%) 8 , and Salvador (63.1%) 13 . This unexpected outcome might be explained by the limited sample size in this study.…”

Capillaria hepatica in Wild Norway Rats (Rattus norvegicus) from Vancouver, Canada

“…Some investigators found no association between C. hepatica prevalence and season (although their analyses were not cluster controlled; Easterbrook et al 2007;Kataranovski et al 2010), while others have noted seasonal variation, attributed to increased prevalence among noninfected, immature rats in spring vs. fall (Childs et al 1988). We found the association between season and C. hepatica to be independent of sexual maturity.…”

“…This inference has been made in previous studies that found a positive association between infection and weight (Farhang-Azad 1977a;Childs et al 1988;Easterbrook et al 2007). However, in our study, sexual maturity was a stronger predictor than weight (the effect of maturity was not specifically examined in the aforementioned studies), suggesting that physiologic, social, or behavioral differences that occur with sexual maturity may be responsible for the observed association.…”

“…Reported prevalence of infection has varied from 11% to 88% (Easterbrook et al 2007;Kataranovski et al 2010). Although several factors associated with infection status have been identified, including host maturity, weight, habitat type, season, and population density (Childs et al 1988;Easterbrook et al 2007;Milazzo et al 2010), the ecology of C. hepatica in rats remains poorly understood. Here, we characterize the ecology of C. hepatica in urban rats from an innercity neighborhood of Vancouver, Canada.…”

Prevalence ofLeptospiraspp. and Seoul hantavirus in brown rats (Rattus norvegicus) in four regions in the Netherlands, 2011-2015

“…Rodents are known to carry pathogens that may be a risk for public health [1–4]. Despite this, little is known about the prevalence and geographical distribution of zoonotic rodent-borne pathogens in the Dutch rodent population.…”