Over 500 people in western Pennsylvania have been affected by an outbreak of hepatitis A, and the number is expected to continue to rise for another week, according to officials in the Pennsylvania State Health Department. So far three people have died as a result of the infection, which is believed to be the largest single outbreak of the disease in the United States.
Authorities in Pennsylvania and at the Centers for Disease Control in Atlanta, Georgia, traced the outbreak to contaminated food at a popular Mexican restaurant, Chi-Chi's, which has chains throughout the country.
Initially they thought the outbreak was due to unsanitary practices, such as an infected worker's poor hand washing, but now the chief culprit has been found to be contaminated spring onions imported from Mexico. The Centers for Disease Control noted that imported spring onions were the cause of smaller hepatitis A outbreaks in Georgia and Tennessee in September. North Carolina also had an outbreak associated with spring onions.
Spring onions are often used in preparing spicy Mexican dishes. Meanwhile, federal authorities are monitoring imports of spring onions from Mexico, and an investigation is ongoing to trace the source. The Centers for Disease Control is advising consumers to avoid lightly cooked spring onions and to consume only those that are thoroughly cooked.
In the wake of the outbreak, record numbers of people are lining up for gammaglobulin injections in Pennsylvania and for the hepatitis A vaccine. Gammaglobulin is effective in preventing onset of hepatitis A if given within two weeks of exposure to the virus, and the hepatitis A vaccine can be given for primary prevention of the disease.