Prevention of Viral Respiratory Infections

摘要

A study of the incidence and etiology (viral and mycoplasmal) of croup, bronchiolitis and pneumonia was initiated. The study group is a population of nearly 8,000 children 5 years and under. Two hundred and eighteen cases were recorded in the first 2 1/2 months of study; throat swabs were obtained on 73% and initial blood specimens on 52%. Initial laboratory results give an isolation rate of 21% for viruses and M. pneumoniae out of 133 specimens successfully tested. Agents recovered were: hemadsorbing agents (11), syncytial agents (3), adenoviruses (2) and M. pneumoniae (12). The pneumonia incidence study showed a higher pneumonia incidence in 1966 (15.4 per 1000) than in 1965 (8.9) or 1964 (14.8). The frequency of isolation of Mycoplasma pneumoniae from pneumonia cases more than doubled in 1966 (16.5%) compared to the two previous years giving an incidence rate for M. pneumoniae pneumonia (2.5 per 1000) two and one-half times the rate in the preceding years (0.8 and 1.0). Patterns of incidence by season, age, sex and geographic location did not change appreciably from those previously reported (6) with the large increase in incidence. Further laboratory studies on viral enhancement with polycationic substances showed that the adenoviruses in addition to the picornaviruses are enhanced by increased Mg(++) (30 mM). Cytopathic effects are more rapid and complete and titration of adenoviruses 2 and 5 in tubes was shown to be more rapid and sensitive. (Author)