The first human case of rabies in Iowa in more than 50 years was reported last year in a man who later died from the infection. The 20-year-old man is believed to have contracted a variant of the rabies virus that is commonly found in silver-haired Lasionycteris noctivagans and eastern pipistrelle bats. Cases of human rabies in the United States are extremely rare today. An average of 11 human cases of rabies were diagnosed annually in the 1950s, and the rate of infection dropped to less than three persons a year during the 1990s. Health officials attribute the decline mostly to the successful control of rabies in domestic dogs. The case in Linn County, Iowa, is the third report of human rabies to have occurred during 2002, and all three cases were linked to viruses identified as bat variants.