Allegheny County Health Department Alert
Over the past couple of months, the Allegheny County Health Department (ACHD) has identified slightly more than 20 county residents with Shigella infection. We usually see about one to two cases over this same time period. When coupled with reports of larger outbreaks in Philadelphia, PA, Berks County, PA and neighboring states, we felt it prudent to encourage you to test for Shigella in persons with bloody diarrhea. While no common exposure has been identified to date, increased testing may identify additional cases and assist in better characterization of risk factors for infection to help target control efforts.
Shigella testing may be conducted through your normal lab protocol. Commercial labs routinely report positive results to ACHD, so no further reporting of positive tests is required on your part. However, we are always happy to receive reports from practitioners, especially when they have clinical information which might be useful in prevention efforts. You also may consider testing close contacts of confirmed cases regardless of symptoms since mildly ill persons may also transmit the disease reducing the effectiveness of control efforts. For uninsured patients, stool specimens may be sent directly to the ACHD laboratory and the testing will be conducted free of charge.
While no outbreak has been identified in a daycare setting, we have taken the added precaution of alerting daycares to the increase in cases and have emphasized the need to follow good hand hygiene and to exclude persons diagnosed with Shigella from daycare settings until they have at least two negative stool cultures taken at least 24 hours apart and 48 hours after the last dose of antibiotic. Food handlers are also at high risk for transmitting Shigella if ill and should similarly be excluded from food preparation until they have at least two negative stool specimens obtained as described above.
We appreciate your assistance in this matter. Please call us at 412-687-ACHD if you have any questions or concerns.
Bruce W. Dixon, M.D.
Allegheny County Health Department
3333 Forbes Avenue
Pittsburgh, PA 15213
Phone: (412) 687-2243 (ACHD)
Fax: (412) 578-8325