Abstract From 2006 through 2008, 543 synanthropic Rattus norvegicus were sampled from 20 alleys clustered in five high-density human neighborhoods throughout Baltimore, Maryland, USA . Results indicated that rat coronaviruses (RCV) circulated endemically and infected most rats in the region. Collected animals were tested by serology and RT-PCR for evidence of exposure to RCV and the results were used to characterize the epizootiology of natural infection. Serology showed that 71.8% of rats had IgG antibodies to RCV, indicating previous exposure, while only 3.0% showed evidence of recent infection based on positive PCR results. Incidence was estimated at 16% per month . Antibody and PCR results were uniformly distributed throughout the city. Consistent with historical laboratory studies, RCV appeared to be horizontally transmitted and generated an acute infection with a short period of infectiousness . Evidence of past infection increased with rat age but did not differ significan...
Media Monitoring for Signals about Emerging Threats