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During an 8-yr period, 862 stool specimens from patients with gastroenteritis were examined by electron microscopy after negative staining with 2% phosphotungstic acid (pH 6.5). Forty-one percent of the specimens submitted over an 8-yr period were determined to be positive for virus or viruslike particles belonging to one or more of seven morphologically distinct viral groups. Coronavirus-like particles (CVLPs) were present in 69.8% of the positive stool specimens. Membranous profiles containing "complement-type" holes (10 nm in diameter) were identified in some preparations containing CVLPs. The second most prevalent viral agent found in stool specimens was the rotavirus (17% of all positive stools). The incidence of other viruses identified in the survey were as follows: adenovirus 4.5%, picorna/parvovirus agents 2.9%, Norwalk-like agent 2.9%, astrovirus 1.9%, and calicivirus 0.5%. Unclassified small round viruses (approximately 25-30 nm in diameter) represented 0.5%. It was also determined that there was a seasonal distribution in excretion of all viruses except for CVLPs. A greater number of viruses were identified in the cooler, drier months of the year.

A fluorescein isothiocyanate-conjugated pool of monoclonal antibodies (MoAb) to respiratory syncytial virus (RSV) was prospectively evaluated for its utility as a direct, 1-hr test for the diagnosis of RSV infection. Direct nasopharyngeal swab smears collected from 109 infants and children with acute respiratory illnesses were studied and compared with results obtained by indirect immunofluorescence using bovine polyclonal anti-RSV antibody on eluted cells derived from pooled nasopharyngeal and throat swab specimens (a 2.5-3 hr procedure), and culture. The MoAb-direct smear method was at least 86%-89% sensitive and 95%-100% specific compared with either of the other procedures. Additional prospective evaluations, as well as retrospective studies on a selected bank of slides stored from the preceding year, established that this MoAb could also be used with confidence in testing where direct smears are not employed.