Routine diagnosis of seven respiratory viruses and Mycoplasma pneumoniae by enzyme immunoassay.

A composite EIA, using 8-well microstrips, was used for the rapid detection of seven respiratory viruses and M. pneumoniae. The viruses included influenza A and B, parainfluenza 1, 2 and 3, adenovirus and respiratory syncytial virus. During the 61 month period--June 1988 to June 1993--17326 respiratory specimens, submitted from three states, were tested by this EIA. The specimens were mainly from a paediatric population (hospitals and private physicians). RSV was the predominant virus detected, followed by adenovirus, parainfluenza 3, M. pneumoniae, influenza A, parainfluenza 2, influenza B and parainfluenza 1. The use of blocking antibodies confirmed the identification of the agents, in particular with samples showing absorbance values greater than the cutoff with more than one infectious agent. Different methods for processing specimens in order to obtain a uniform suspension, and interpretation of non-specific reactions, are discussed. The assays showed an average sensitivity of 85% and specificity of 99%, compared to virus culture. This EIA system provided an efficient method for the rapid diagnosis of viral and mycoplasmal infections in a busy diagnostic laboratory.

Recognition of adenovirus types in faecal samples by southern hybridization in South Australia.

The distribution of adenovirus types in faecal samples of patients with suspected viral gastroenteritis from South Australia was determined during the 12-month period, July 1991-June 1992. There were 3299 samples tested and 226 (6.9%) were positive for adenovirus by enzyme immunoassay. Of these 226 samples, 154 (68%) were typed directly using virus DNA extracted from the faecal samples according to the Sma I, Hind III and BstE II restriction patterns and Southern hybridization analysis with pooled viral genomic DNA probes. In this group, 86% of the samples were from patients who were < 3 years of age. Enteric adenovirus types 40 and 41 accounted for 20 and 40% respectively, of these samples, and types 1, 2, 3, 5, 6, 7 and 31 comprised the remainder. Type 40 was detected mainly in the winter and spring periods, and type 41 predominated in the autumn period. The majority of the non-enteric types were found during the late winter and spring periods.