The outbreak of West Nile disease in the United States moved a step closer to becoming the second worst on record with federal health authorities reporting 280 cases of the virus-caused illness over the past week. According to the Centers for Disease Control and Prevention, there have now been 4,249 cases of West Nile recorded this year. 20 cases fewer than in 2006, the second-largest outbreak on record. The number of deaths rose by five to 168 since last week. More than 70% of the cases have been reported in eight states: Texas, Mississippi, Michigan, South Dakota, Louisiana, Oklahoma, Illinois and California. The worst year on record for West Nile disease was 2003, when 9,862 cases were reported.