The relationship between respiratory syncytial virus (RSV) strain and disease severity was assessed in 265 hospitalized infants over a 3-year period (1988-1991). A severity index of clinical and physiologic parameters was used to grade illness severity. Multivariate analysis of 134 infants infected with group A RSV strains and 131 infants infected with group B strains indicated that prematurity, underlying medical conditions, group A RSV infection, and age < or =3 months were independently associated with severe disease. Odds ratios for severe disease for these risk factors were 1.83, 2.84, 3.26, and 4.39, respectively. Among infants without underlying medical conditions, group B RSV infection rarely required ventilatory support, in contrast to group A infections (1/90 vs. 13/107; P < .006), and had significantly lower severity indices (mean +/- SD, 0.6 +/- 9 vs. 1.3 +/- 1.9; P = .05). Results confirm earlier findings that group A RSV infection results in greater disease severity than group B infection among hospitalized infants.

BACKGROUND:Acute respiratory illnesses (ARIs) are the leading cause of medical visits for community-dwelling patients of all ages, but virologic and clinical descriptions of these illnesses in older adults are infrequent.OBJECTIVES:To determine the feasibility of influenza surveillance in a population of community-dwelling elderly, to compare the patterns of influenza infection in elderly persons with that observed in young populations in which surveillance is usually conducted, and to describe the clinical presentation of influenza infection in elderly outpatients who seek medical attention for ARI.DESIGN:Prospective clinical and viral surveillance of ARIs among ambulatory patients during 3 consecutive winter seasons.SETTING:Nine internal medicine and 3 pediatric practices in Upstate New York in cooperation with the Medicare Influenza Vaccine Demonstration Project.PATIENTS:Elderly (n=808) and pediatric (n=2080) outpatients with ARI office visits.MEASUREMENTS:Frequency of influenza and other respiratory virus isolates and clinical profile of influenza among older adults and children with ARIs.RESULTS:Influenza virus was the viral agent recovered most often from specimens obtained from patients in both age groups with ARI symptoms, especially those with fever. Influenza accounted for 11% of ARIs in adults (87 isolates) and 20% in children (408 isolates). At the initial illness visit, influenza infection was equally common in elderly individuals with or without underlying cardiopulmonary conditions. Lower respiratory tract signs occurred in 13% of the adults and in 7% of the children with influenza documented by laboratory studies. Other respiratory viruses were recovered from specimens obtained from 20 adults and from 259 children.CONCLUSIONS:Viruses are important agents of ARIs in elderly outpatients. Children and older adults experience similar patterns of influenza infection and other epidemic respiratory pathogens, such as parainfluenza and respiratory syncytial viruses. Viral identification is feasible in older adults seen in physicians' offices and may contribute to improved measures of effects of influenza and other respiratory viruses on ARIs.

We collected surveillance data as part of the Medicare Influenza Vaccine Demonstration to describe communitywide epidemiology of influenza, focusing on the elderly. Laboratory-based surveillance was established in medical practices, hospitals, and nursing homes in a two-county demonstration in upstate New York. Time course and intensity of epidemic influenza were compared between counties, between influenza A and B epidemics, and among several levels of surveillance involving elderly persons as well as children during the years 1989-1992. The counties experienced parallel epidemics during each of the three demonstration years. Influenza A/H3N2, predominant in 1989-1990 and 1991-1992, was equally intense among young and old, accounted for 11%-28% of acute cardiopulmonary hospitalizations of older persons, and caused focal outbreaks in 30%-40% of nursing homes in the respective epidemics. Influenza B, predominant in 1990-1991, showed modest impact among the elderly as compared with children. Influenza A/H1N1 occurred among children each year but was virtually absent among the elderly. Systematic surveillance during the "influenza season" consistently confirms widespread infection among older patients, both in the community and in institutions. However, much febrile respiratory illness in this age group during periods of epidemic influenza is culture-negative for influenza virus and thus may be caused by other respiratory pathogens.

The impact of nosocomial viral disease, in terms of morbidity, mortality, and health care expenditures, should not be underestimated. Respiratory viruses, in particular, account for a substantial proportion of all nosocomial infections, especially among pediatric patients and the institutionalized elderly. The immunocompromised, very young, and chronically ill patients in hospitals are unusually vulnerable to serious viral illness. The emerging technology of rapid viral diagnosis will allow more timely and accurate recognition of viral infections, even in the smaller hospital with limited laboratory resources. Early recognition of viral diseases should, in turn, permit us to institute, and further evaluate, specific measures for their control. Appreciation of the epidemiology and transmission of these viruses will provide the framework for successful infection control strategies.

A case of a rare acquired form of aqueductal stenosis and hydrocephalus developing as a late sequela of mumps virus infection of the central nervous system is presented. The experimental studies of mumps induced aqueductal stenosis in hamsters and mice and the four previously reported cases in the literature are reviewed.