MODES OF SEOUL VIRUS-INFECTIONS - PERSISTENCY IN NEWBORN RATS AND TRANSIENCY IN ADULT-RATS

To understand the mode of persistent infection of Seoul virus in roden ts, we examined the distribution of the virus genome and antibody prod uction in infected rats. When 1-day-old rats were inoculated with the KI-83-262 strain, the S segment of viral genome was detected in sera, clots, lungs and kidneys from 3 to 184 days post inoculation (d.p.i.) by nested reverse transcriptase PCR. On the other hand, when 7-week-ol d rats were infected with this virus, viral genome was detected only i n the lungs from 3 to 50 d.p.i. The neutralizing antibody titers of ra ts inoculated at 1-day of age were higher than those of rats inoculate d at 7 weeks of age. In both a ge groups, however, the IgG avidity of antibody increased along with the course of infection. We found that u rban rats (Rattus norvegicus) infected early in life harbored the viru s for more than 6 months.