Intramuscular injections within 30 days of immunization with oral @entity9925 vaccine--a risk factor for vaccine-associated XXXX .

@entity1 @entity66 @entity3328 @entity9925 @entity221 @entity912
BACKGROUND: In Romania the rate of vaccine-associated @entity3328 is for unexplained reasons 5 to 17 times higher than in other countries. Long ago it was noted that intramuscular injections administered during the incubation period of wild-type @entity9925 infection increased the risk of @entity66 (a phenomenon known as "provocation" @entity3328 ). We conducted a case-control study to explore the association between intramuscular injections and vaccine-associated @entity3328 in Romania. METHODS: The @entity1 were 31 young @entity1 in whom vaccine-associated @entity3328 developed from 1988 through 1992. Eighteen were vaccine recipients, and 13 had acquired the disease by contact with vaccine recipients. Each of these @entity1 was matched with up to five controls according to health center, age, and in the case of vaccine recipients, history of receipt of the live attenuated oral @entity9925 vaccine. Data were abstracted from medical records that documented the injections administered in the 30 days before the onset of @entity912 . RESULTS: Of the 31 @entity1 with vaccine-associated disease, 27 (87 percent) had received one or more intramuscular injections within 30 days before the onset of @entity912 , as compared with 77 of the 151 controls (51 percent) (matched odds ratio, 31.2; 95 percent confidence interval, 4.0 to 244.2). Nearly all the intramuscular injections were of antibiotics, and the association was strongest for the @entity1 who received 10 or more injections (matched odds ratio for > or = 10 injections as compared with no injections, 182.1; 95 percent confidence interval, 15.2 to 2186.4). The risk of @entity66 was strongly associated with injections given after the oral polio virus vaccine, but not with injections given before or at the same time as the vaccine (matched odds ratio, 56.7; 95 percent confidence interval, 8.9 to infinity). The attributable risk in the population for intramuscular injections given in the 30 days before the onset of @entity912 was 86 percent (95 percent confidence interval, 66 to 95 percent); that is, we estimate that 86 percent of the cases of vaccine-associated @entity3328 in this population might have been prevented by the elimination of intramuscular injections within 30 days after exposure to oral @entity9925 vaccine. CONCLUSIONS: Provocation @entity912 , previously described only for wild-type @entity9925 infection, may rarely occur in a @entity1 who receives multiple intramuscular injections shortly after exposure to oral @entity9925 vaccine, either as a vaccine recipient or through contact with a recent recipient. This phenomenon may explain the high rate of vaccine-associated @entity3328 in Romania, where the use of intramuscular injections of antibiotics in @entity1 with @entity221 is common.
