red berries
The ultimate source of an outbreak of Hepatitis A traced to frozen berries hasn't yet been determined. (Digital Vision/Thinkstock)

At least 119 people have been sickened with hepatitis A as of June 21 in an outbreak that has affected seven states, the latest update on the case from the U.S. Centers for Disease Control and Prevention (CDC) has revealed.

The outbreak, whose source has been identified as frozen berries produced by Townsend Farms and sold in Costco outlets, has led to the hospitalization of 53 people so far. The product, called Townsend Farms Organic Antioxidant Blend, which is a frozen berry and pomegranate mix, was recalled on June 3 but hepatitis A takes a few weeks to show up on tests and cases have been reported since then. Apart from Costco, the frozen berries were also sold at Harris Teeter stores but all of the people with confirmed cases purchased the product from Costco.

California has the biggest number of people infected, having reached 61. There are 24 people sickened in Colorado, 16 in Arizona, five each in Hawaii, Nevada and New Mexico and three in Utah, the latest report by the CDC stated. The product was also distributed in Alaska, Idaho, Montana, Oregon and Washington but no hepatitis A cases that could be linked to the outbreak were reported. More than two in three of the confirmed cases are female, the data also showed.

FDA issues warning about Brooklyn-based juice manufacturer

The CDC is continuing its investigation along with the Food and Drug Administration (FDA) and local and state health departments. The FDA is currently inspecting Townsend Farms facilities in Oregon, where the contaminated product was manufactured.

Hepatitis A is a highly contagious liver infection caused by a virus. In many cases affected people are not aware of the disease because they have no symptoms, but fever, fatigue, nausea, vomiting, and abdominal and joint pain are commonly associated with it. In the most serious cases it can cause liver failure and may even require a transplant.

The disease is typically transmitted through fecal contamination. The most common method of contamination is when people consume food or water contaminated with feces from an infected individual. Another frequent way the disease is transmitted is when food prepared by an infected person who did not properly wash their hands after going to the bathroom is consumed.

European Hepatitis A outbreak linked to frozen berries

Overall, Hepatitis A rates in the United States have steeply decreased since 1995, when a vaccine was first introduced. The average number of affected people has dropped by 95 percent since then, the CDC stated.

According to Craig Wilson, Costco food-safety director, the company has taken all measures to protect its consumers. It voluntarily recalled its product as soon as it was aware of the problem and has called all its customers who bought the berry mix between February and May.