Transmission of invasive XXXX type b disease in day care settings.

@entity1 @entity34200 @entity66 @entity327 @entity6932 @entity1215 @entity6476
We prospectively studied the risk of secondary transmission of invasive @entity327 type b (Hib) disease among @entity1 in day care in @entity6476 . We established a statewide surveillance system for the reporting of all forms of invasive @entity6932 from physicians, clinical laboratories, county health departments, and infection control practitioners from all hospitals in and bordering @entity6476 . For the 2-year period March 15, 1984, to March 15, 1986, there were 409 culture-confirmed cases of invasive @entity6932 in @entity1 12 years of age or younger; 147 (37%) case- @entity1 attended day care. When a case- @entity1 attended day care during the week before illness, we prospectively identified and observed all classroom contacts (n = 2147) for the next 60 days. Of 1253 classroom contacts younger than 4 years of age, seven (0.6%) secondary cases were identified. Isolates from all paired index and secondary cases had identical @entity34200 ( @entity34200 ) patterns. Strains causing @entity66 were indistinguishable by @entity34200 distribution from those causing secondary disease. Of 685 classroom contacts younger than 2 years of age from whom @entity1215 use was ascertained, five (1.7%) of 292 who did not receive @entity1215 became secondary cases, compared with one (0.3%) of 393 who received @entity1215 (rate ratio 6.7; 95% confidence limits 1.1, 42.5; P less than 0.05). Of 495 classroom contacts 24 to 47 months of age for whom @entity1215 use was ascertained, one (0.5%) of 194 who did not receive @entity1215 became a secondary case, compared with none of 301 who received @entity1215 . This experience indicates that secondary transmission of invasive @entity6932 can be appreciable in day care settings, particularly in @entity1 younger than 2 years of age, and that @entity1215 prophylaxis reduces this risk.
