Viruses were isolated from nasal washings of volunteers receiving experimental therapy for rhinovirus type 9 infection with intranasal sprays of a new synthetic antiviral R61837. On a screening test nine subjects yielded drug sensitive virus and four resistant virus. In four others the virus was sensitive at first but became resistant later, while in one the reverse occurred. Evidence is given that at least some of the resistant viruses were present in the respiratory tract and were not selected during virus isolation. Of six viruses studied in detail, five had a low degree of resistance and one was highly resistant. The degree of resistance of the five was similar for an antiviral chalcone, dichloroflavan and disoxaril. The sixth was different in that the resistance to disoxaril was relatively less than to the other drugs. The significance of these results is discussed--these are the first experiments in man to show the selection of drug resistant rhinovirus.

Forty-one human T-cell lymphotropic virus type I (HTLV-1)-seropositive individuals were identified among 1,012 subjects with stored serum samples from a health and seroepidemiological survey conducted in Barbados in 1972. These 41 subjects plus 79 HTLV-1 seronegative household members were targeted in a follow-up study 20 years later. Sixteen seropositive subjects and 22 seronegative subjects were interviewed, examined, and phlebotomized. There were no changes in HTLV-1 serostatus between the 1972 and follow-up serum samples. Three (19%) of the seropositive subjects had HTLV-1-associated disorders: two with dermatitis and one with "smoldering" adult T-cell leukemia. Neurologic and immunologic function was similar in HTLV-1-seropositive and HTLV-1-seronegative subjects. HTLV-1 antibodies persist over many years, and the risk for seroconversion of household contacts is low.

This paper describes the first enzyme-linked immunosorbent assay for the detection of rhinovirus antigens in clinical specimens (nasal washings), either directly or following overnight cell culture amplification. The assay takes approximately 48 hours to perform and utilizes the same rabbit antirhinovirus hyperimmune serum as both the capture and detecting antibody. The latter has been biotin-labelled and is detected via a streptavidin beta-galactosidase preformed complex. This new assay has been found to be very sensitive, detecting human rhinovirus (HRV)-EL and HRV-2 at titres as low as 10(1.8) TCID50 100 microliter-1 and less than 10(1)TCID50 100 microliter -1, respectively. Furthermore, when 57 different human rhinovirus serotypes were tested in both the HRV-EL and HRV-2 ELISA systems a total of 49 (86%) were found to be cross-reactive. Of 36 clinical specimens tested by virus isolation, cell-culture-amplified (CCA) ELISA, and direct ELISA, 15 were positive by isolation, 11 by CCA-ELISA, and 11 by direct ELISA. The overall correlation of the CCA and direct ELISA techniques with virus isolation was found to be 88.9% and 66.7%, respectively. The present study demonstrates that the ELISA system developed is a sensitive technique for the diagnosis of rhinovirus infections.

This study describes the evaluation of a newly developed ELISA for the direct detection of rhinovirus antigens in nasal washings. Of 54 volunteers inoculated with 100 TCID50 of human rhinovirus type 2 (HRV-2), 50 (96.6%) and 32 (59%) excreted antigen and virus on at least 1 of 3 days investigated, respectively. Thirty-three (61%) had significant rises in rhinovirus-specific IgA by ELISA. Twelve (22%) developed symptoms of colds. Generally the ELISA detected antigen more frequently in volunteers later in the course of infection and provided evidence of infection in a higher proportion of asymptomatic compared with symptomatic volunteers. On the other hand, virus isolation detected virus more frequently earlier in the course of infection and in a higher proportion of symptomatic compared with asymptomatic volunteers. We conclude that rhinovirus antigen detection by ELISA is a simple, rapid, sensitive, and practical test to diagnose a rhinovirus infection and potentially a viable alternative to virus isolation.