By Elizabeth Weise, USA TODAY
The nationwide outbreak of hepatitis A linked to frozen berries grew to 79 Friday, but is sparing children.
Of the 79 people in seven states who have become ill with the deadly liver disease, only one was a child.
Health officials initially feared that the youngest would be hit hardest because the contaminated frozen berries are used in smoothies, popsicles and other warm-weather treats popular among children.
They credit routine vaccinations against hepatitis A since 2006 with protecting children.
"The very, very small number of children involved in this outbreak probably reflects the high vaccination coverage as the result of the routine immunization," said John Ward, who directs the viral hepatitis program at Centers for Disease Control and Prevention (CDC).
The one child who did become ill, a 2-year-old, was not vaccinated, Ward said.
Eleven of the 61 people have been hospitalized; no deaths have been reported, the CDC said. Officials expect the number of illnesses to grow. People have gotten sick in Arizona, California, Colorado, Hawaii, Nevada, New Mexico and Utah.
Hepatitis A is a highly contagious liver infection caused by a virus. Some people have no symptoms, but many have fever, fatigue, nausea, vomiting, and abdominal and joint pain. In severe cases it can cause liver failure and require a transplant.
The hepatitis A vaccine is given to children twice, first between 6 and 12 months and then six months later, said CDC's Trudy Murphy, a hepatitis expert. The vaccine became available in 1996. In 2006 CDC recommended that all children be vaccinated against the virus.
Widespread vaccination is having an impact. In 1995 there were 31,582 hepatitis A cases in the United States. In 2010, the most recent year for which numbers are available, there were 1,670, according to CDC.
"It's a very powerful vaccine, it gives you several decades of protection," said Ward.
CDC officials have linked the outbreak to Townsend Farms Organic Antioxidant Blend frozen berry and pomegranate mix sold by Costco and Harris Teeter stores. The Harris Teeter product was labeled "Harris Teeter Organic Antioxidant Berry Blend, 10 oz. bag."
Townsend Farms of Fairview, Ore., voluntarily recalled its frozen Organic Antioxidant Blend on June 3.
Costco has called all 50,000 customers who bought the berry mix between February and May, said Craig Wilson, the company's food safety director. The Issaquah, Wash., company is reimbursing the cost of hepatitis A vaccination for everyone who bought the frozen berry mix at Costco and ate it in the last 10 days. All Costco pharmacies are making the vaccine available to affected customers, Wilson said.
The strain of hepatitis A found in the berry mix is rare in the United States but known to circulate in North Africa and the Middle East. According to the label, the Townsend Farms Organic Antioxidant Blend mix associated with this outbreak contained fruit from the United States, Argentina, Chile and Turkey.
The first victims fell ill on April 29. The most recent case was reported May 27.
The virus is most often transmitted when an infected food handler prepares food with dirty hands. Food contaminated with hepatitis A can transmit the disease to people who eat or handle it.