Rubella outbreak among hospital employees.

A rubella outbreak among medical staff on the obstetric service of a large Los Angeles hospital was studied. Fifteen cases of suspected rubella were reported among hospital personnel during a 2-month period in 1978. Of these, 4 were confirmed, 2 by viral isolation and serology and 2 by serologic study alone. A fifth case, the index, had a convalescent-phase serum with an elevated rubella hemagglutination inhibition (HAI) antibody titer. A list of 231 pregnant women who may have been exposed to any of the 15 suspect cases was assembled. The authors succeeded in contacting and obtaining postexposure sera for only 140 (61%) of the exposed women. Thirty-five (25%) of these women were without detectable rubella HAI antibody. A second serum sample was obtained from 93 women 2 to 3 weeks after the first, and no fourfold rises in titer were observed. To evaluate those with suspicious high stationary titers, 60 specimens were selected for immunoglobulin M (IgM) testing. Only 1 was positive for IgM antibody. A postexposure illness survey revealed that 20 (15%) of 130 women reported various rash-like illnesses after their visit to the hospital. There were no reports of affected offspring in any of the exposed women. Four hundred ten staff members submitted sera for antibody testing; 76 (19.2%) were without detectable rubella HAI antibody. This outbreak is discussed in light of recent changes in rubella epidemiology, and several recommendations for hospital policy are proposed.