Skip Navigation LinksSkip Navigation Links
Centers for Disease Control and Prevention
Safer Healthier People
Blue White
Blue White
bottom curve
CDC Home Search Health Topics A-Z spacer spacer
Blue curve MMWR spacer

Respiratory Syncytial Virus and Parainfluenza Virus Surveillance -- United States, 1989-90

To provide public health officials and health-care providers with additional information about the epidemiology of respiratory syncytial virus (RSV) and parainfluenza virus infections, CDC recently expanded its Respiratory and Enterovirus Surveillance System. Awareness by health-care providers of circulation of these respiratory pathogens in the community may enable more effective treatment of affected patients and institution of appropriate control measures. This report summarizes data from the expanded surveillance system for July 1989 through June 1990.

Data on RSV and parainfluenza viruses were provided by 94 laboratories participating in the National Respiratory Virus Surveillance System (NRVSS). These included 80 university or community hospital laboratories, 10 state or county public health laboratories, and four commercial laboratories. These laboratories, which represent 49 states, provided monthly reports of the number of specimens tested for RSV and the number of specimens positive by antigen-detection techniques, serology, or viral culture. Of these 94 laboratories, 52 also provided data on results of testing for parainfluenza viruses. Most laboratories performed enzyme immuno assay (EIA) and/or direct fluorescent antibody (DFA) tests to detect RSV (56% and 53%, respectively). For parainfluenza viruses, most laboratories performed DFA and/or indirect fluorescent antibody (IFA) tests (50% and 83%, respectively). This report includes data from laboratories that submitted reports for at least 8 of the 12 months.

Data were also provided by an additional 12 state health department laboratories* that submitted monthly reports on the number of RSV or parainfluenza virus isolates identified in conjunction with reports on enterovirus isolations.

From July 1989 through June 1990, 71 NRVSS laboratories in 45 states tested 52,496 specimens for RSV; of these, 11,884 (23%) were positive. Detection of RSV peaked in January, when 4104 specimens were positive (35% of all positive specimens) (Figure 1). Detections peaked in January throughout the United States except in the West South Central region, where the peak occurred in December. The state health department laboratories reported 245 isolations of RSV, which peaked in February, when 90 isolates were positive (37% of all positive specimens).

During the same period, 38 NRVSS laboratories tested 33,060 specimens for parainfluenza viruses. Of these, 518 (1.6%) were parainfluenza virus type 1 (P1); 182 (0.6%), parainfluenza virus type 2 (P2); and 478 (1.5%), parainfluenza type 3 (P3). P1 and P2 identification peaked in November with 150 and 59 detections, respectively (29% and 32% of positive specimens by type, respectively); P3 identification peaked in May with 137 detections (29% of positive specimens) (Figure 2). The state public health laboratories reported 60 isolations of P1, 35 isolations of P2, and 76 isolations of P3. P1 activity peaked in October and December (13 isolates each month (22% of positive specimens)), and P2, in October (nine isolates (26% of positive specimens)); in comparison, P3 activity peaked in May (13 isolates (17% of positive specimens)). Reported by: School of Public Health, Emory Univ, Atlanta. State and territorial public health laboratories. National Respiratory Virus Surveillance System Laboratories. Respiratory and Enterovirus Br, Div of Viral and Rickettsial Diseases, Center for Infectious Diseases, CDC.

Editorial Note

Editorial Note: RSV is the single most important respiratory pathogen of infancy and early childhood worldwide; in temperate climates, RSV causes yearly outbreaks of pneumonia and bronchiolitis in the winter and early spring (1,2). Outbreaks caused by parainfluenza viruses occur during alternate years in the fall (P1 and P2) or throughout the year, with increased activity in the spring (P3) (2). The surveillance data in this report are consistent with previously described seasonal characteristics of these viruses: RSV was the most commonly identified pathogen, and detections peaked in the winter season.

Although RSV and parainfluenza virus infections primarily cause serious infections in infants and young children, they also can cause severe disease in adults, especially elderly and immunocompromised adults (3,4). Because RSV outbreaks have been associated with increased hospitalizations (1) and mortality (5), detection of RSV in the community should alert health-care providers to diagnostic considerations and to management (6) and prevention options (7). Patients with compromised immune (8), cardiac (9), or pulmonary (10) systems are at increased risk for serious complications of RSV infection and may be most likely to benefit from effective infection-control practices (7) and antiviral chemotherapy (6).

To provide more timely surveillance information about these viruses, beginning with the 1990-91 season, CDC is changing from a monthly postcard reporting system to a weekly telephone-based reporting system. Participating NRVSS laboratories will report the number of respiratory viruses detected each week by telephone through a computer polling service. This information will be automatically tabulated and made available by the middle of the following week to reporting laboratories, state health departments, and others through the Public Health Network.


  1. Kim HW, Arrobio JO, Brandt CD, et al. Epidemiology of

respiratory syncytial virus infection in Washington, D.C. I. Importance of the virus in different respiratory tract disease syndromes and temporal distribution of infection. Am J Epidemiol 1973;98:216-25.

2. Easton AJ, Eglin RP. Epidemiology of parainfluenza virus type 3 in England and Wales over a ten year period. Epidemiol Infect 1989;102:531-5.

3. Morales F, Calder MA, Inglis JM, Murdoch PS, Williamson J. A study of respiratory infections in the elderly to assess the role of respiratory syncytial virus. J Infect 1983;7:236-47.

4. Englund JA, Sullivan CJ, Jordan C, Dehner LP, Vercellotti GM, Balfour HH Jr. Respiratory syncytial virus infection in immunocompromised adults. Ann Intern Med 1988;109:203-8.

5. Anderson LJ, Parker RA, Strikas RL. Association between respiratory syncytial virus outbreaks and lower respiratory tract deaths of infants and young children. J Infect Dis 1990;161:640-6.

6. American Academy of Pediatrics, Committee on Infectious Diseases. Ribavirin therapy of respiratory syncytial virus. Pediatrics 1987;79:475-8.

7. Garner JS, Simmons BP. Guideline for isolation precautions in hospitals. Infect Control 1983;4(suppl):245-325.

8. Hall CB, Powell KR, MacDonald NE, et al. Respiratory syncytial viral infection in children with compromised immune function. N Engl J Med 1986;315:77-81.

9. MacDonald NE, Hall CB, Suffin SC, Alexson C, Harris PJ, Manning JA. Respiratory syncytial viral infection in infants with congenital heart disease. N Engl J Med 1982;307:397-400. 10. Groothuis JR, Gutierrez KM, Lauer BA. Respiratory syncytial virus infection in children with bronchopulmonary dysplasia. Pediatrics 1988;82:199-203.

  • Arizona, Connecticut, Missouri, New Mexico, New York, Ohio, Oklahoma, Pennsylvania, South Carolina, Texas, Virginia, and Wisconsin.

Disclaimer   All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to

Page converted: 08/05/98


Safer, Healthier People

Morbidity and Mortality Weekly Report
Centers for Disease Control and Prevention
1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A


Department of Health
and Human Services

This page last reviewed 5/2/01