The Food and Drug Administration is investigating two brands of organic strawberries in connection with an outbreak of hepatitis A, a contagious virus that is generally mild but can cause liver disease in severe cases. In a statement, the FDA said the strawberries were sold at several large retailers, including Trader Joe’s, Walmart, Aldi, Kroger, and Safeway. The potentially tainted fruit, which is past its shelf life, carried a FreshKampo or H-E-B label, the agency said. H-E-B said in a statement on its website that its strawberries are safe to consume. The agency, however, is advising anyone who bought either brand between March 5 and April 25 and froze the strawberries to dispose of the fruit immediately. So far, 17 people in California, Minnesota, and Canada have fallen ill, and 12 have been hospitalized.