25- to 30-nm virus particle associated with a hospital outbreak of acute gastroenteritis with evidence for airborne transmission.
Between November 1 and 22, 1985, an outbreak of acute, nonbacterial gastroenteritis occurred in a 600-bed hospital in Toronto, Ontario, Canada. Illness in 635 of 2,379 (27%) staff was characterized by fatigue, nausea, diarrhea, and vomiting and had a median duration of 24-48 hours. The finding of virus-like particles measuring 25-30 nm in six stool specimens and low rates of seroresponse to Norwalk virus (3/39) and Snow Mountain agent (1/6) suggest that a Norwalk-like virus was responsible for the outbreak. The outbreak was of abrupt onset and high incidence, affecting 79 people in a single day. No common food or water exposure could be identified. The attack rate was greatest (69%) for staff who had worked in the Emergency Room. Of 100 patients and their companions who visited the Emergency Room on November 11-12 for unrelated problems, 33 (33%) developed gastroenteritis 24-48 hours after their visit, versus 0 of 18 who visited the Emergency Room on November 8 (p less than 0.001). An analysis of housekeepers who worked at least once during the period from November 9-13, which included those who became ill during the period of November 9-14, showed that the risk of becoming ill was four times greater for those who visited or walked through the Emergency Room than for those who did not (p = 0.028). These data are consistent with the possibility of the airborne spread of a virus.
Sawyer
L A
LA
Division of Viral Diseases, Centers for Disease Control, Atlanta, GA 30333.
Murphy
J J
JJ
Kaplan
J E
JE
Pinsky
P F
PF
Chacon
D
D
Walmsley
S
S
Schonberger
L B
LB
Phillips
A
A
Forward
K
K
Goldman
C
C
D000328:Adult; D000391:Air Microbiology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D004196:Disease Outbreaks; D004636:Emergency Service, Hospital; D004812:Epidemiologic Methods; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D006757:Hospital Units; D006801:Humans; D008297:Male; D008875:Middle Aged; D009663:Norwalk virus / Q000302:isolation & purification*; D009864:Ontario; D014771:Virion / Q000302:isolation & purification; D014777:Virus Diseases / Q000453:epidemiology* / Q000635:transmission