The temporal patterns of respiratory virus isolations from 10 laboratories in the USA were compared with that of deaths of children less than 5 years old from July 1975 through June 1984. Isolations of respiratory syncytial virus (RSV) occurred as yearly winter outbreaks; parainfluenza virus 1 and 2 isolations occurred as well-defined outbreaks every other year in the autumn; parainfluenza virus 3 isolations occurred throughout the year with periodic, increased isolations suggestive of outbreaks; and influenza virus isolations (A, B, or A plus B) occurred as yearly winter outbreaks. After data were controlled for seasonal patterns, RSV isolations were strongly correlated with the winter peaks in lower respiratory tract illness (LRI) deaths of infants 1-11 months old; influenza virus isolations were correlated with the winter peak in LRI deaths of children 24-59 months old. The parainfluenza viruses were not correlated with respiratory deaths. This study supports the idea that RSV is a major contributor to winter peaks in LRI deaths of children 1-11 months old.

To determine the diagnostic use of different markers of acute parvovirus B19 infection, serum specimens obtained from 128 persons with erythema infectiosum were tested for specific immunoglobulin G (IgG), IgA, and IgM antibodies by capture enzyme immunoassay (EIA) using Chinese hamster ovary (CHO) cell-expressed B19 antigen, and tested for circulating B19 DNA by polymerase chain reaction (PCR). A significant rise in specific IgG and IgA antibodies was detected in 87% and 77%, respectively, of persons from whom acute- and convalescent-phase serum specimens were available. Specific IgA antibodies were detected in single serum specimens from 90% of cases and were present in 22 (18%) of 120 persons from a control group without a history of recent exposure to B19. Specific IgM antibodies were detected in 97% of cases and one person (1%) from the control group. B19 DNA was detected in 94% of cases and was absent in 20 persons from the control group positive for both IgG and IgA antibodies. Serum specimens obtained between 4 and 6 months after onset of illness from six additional persons were also tested. All had specific IgG antibodies, four (67%) had IgA, five (83%) had IgM, and none had detectable B19 DNA. Our data indicate that 1) specific IgA antibodies are too persistent to be a useful indicator of recent B19 infection; 2) specific IgM antibodies are the most sensitive indicator of acute B19 infection in immunologically normal persons but can persist up to 6 months; and 3) B19 DNA can often be detected up to 2 months after onset of illness even in immunologically normal hosts and might be a useful adjunct test for diagnosis of acute B19 infection.

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Human parvovirus B19 (B19) infection during pregnancy has been associated with fetal deaths. We conducted several studies to develop data needed to make recommendations for preventing fetal death associated with infection. In the first study, after an outbreak of B19 infection, specimens of cord blood from 47 infants with congenital anomalies, 10 with suspected intrauterine infection, and gestational age-matched controls were tested for IgG and IgM antibodies to B19. None had evidence of recent infection. Next, 192 women with unknown exposure to B19 who had stillbirths or spontaneous abortions were studied. Two patients and two controls had evidence of recent B19 infection. In a second case-control study of women who had stillbirths after outbreaks of erythema infectiosum in area schools, none of the 20 patients or 26 controls were IgM positive at the time of delivery. The rate of infection, as demonstrated by IgM positivity, among 267 pregnant control subjects was approximately 1%. These studies suggest that among pregnant women unselected for exposure to B19, neither infection nor stillbirths are common.

Infection due to parvovirus B19 is common and usually resolves over several weeks. Prolonged infection has been reported primarily in immunodeficient hosts. The present report describes a chronic infection in an apparently immunologically healthy woman. The illness was characterized by recurrent episodes of paresthesia without anemia. Laboratory studies demonstrated persistence of parvovirus-specific DNA for nearly 4 years.