URINE-ASSOCIATED HORIZONTAL TRANSMISSION OF SEOUL VIRUS AMONG RATS

To understand the mode of transmission of Seoul type hantavirus in Wis tar rats, we examined the shedding of the virus and antibody productio n in infected rats. When 1-day-old rats were inoculated with the KI-83 -262 strain of Seoul virus, S segment of the viral genome was detected in lungs, clots, urine, saliva, submaxillary glands, rectums, and kid neys by nested reverse transcriptase PCR. On the other hand, when 8-we ek-old rats were infected with the virus, viral genome was detected on ly in the lungs and rectum. In newborn rats intranasally administered urine from infected newborn rats, four of six rats shed the virus into their urine. In addition, three of eight rats kept in the same cage w ith infected animals also shed the virus into urine. Moreover, the vir us genome was detected in the urine of urban rats (Rattus norvegicus) in an enzootic focus. These findings suggest that the urine containing virus from infected rats is an actual source of the Seoul virus infec tion.