In 2013, an outbreak of hepatitis A made 162 people in 10 states sick after they ate a berry blend product purchased at a national chain store.

CDC detected the outbreak on May 15. Scientists promptly applied whole genome sequencing and other advanced analytic methods to establish that not only were the infecting strains identical, but also belonged to an unusual hepatitis A virus genotype that is rare in the United States.

CDC completed its analysis within a week of receiving samples from the first 20 cases. This automated technology proved to be quicker, simpler and more sensitive than if the samples had been processed by previous methods. As the outbreak spread, other cases also were found to be infected by the same viral strain.

Advanced molecular detection helped CDC and the U.S. Food and Drug Administration (FDA) link this specific strain of the virus with the outbreak investigation data to identify quickly a shipment of pomegranate seeds from Turkey as the source of the outbreak. With this information FDA was able to identify the company selling the seeds and take action to ensure shipments were stopped until checked. FDA worked with pomegranate seed distributors to make sure all recipients were notified.

A public announcement about the risk related to the product was made on May 31. Local public health departments and the retail chain that sold the product vaccinated more than 10,000 people as a precaution in case someone had been exposed.

Advanced molecular detection methods helped stop this outbreak in its tracks in record time, better protecting the health of the public.