Indiana chickenpox outbreak largest in US, official says TERRE HAUTE, Ind. - The chief medical officer of the Indiana State Department of Health says western Indiana's Vigo County is experiencing the largest known current outbreak of chickenpox in the U.S. Dr. Joan Duwve (DUH'-vee) told the Terre Haute Tribune-Star for a story this week that Vigo County usually has fewer than 10 cases per year but had had 84 since September. The Vigo County health Department has scaled back the number of cases after reporting more than 100 cases earlier in the week. Duwve says it's not clear why the county is having such a large outbreak. Neighboring Parke County has had cases at one school. Vigo County School Corp. officials excluded 230 students from school last week because of the outbreak.