Reported Cases of Lyme Disease by Year, United States, 1996-2010
*National Surveillance case definition revised in 2008 to include probable cases; details at http://www.cdc.gov/osels/ph_surveillance/nndss/casedef/lyme_disease_2008.htm
*National Surveillance case definition revised in 2008 to include probable cases; details at http://www.cdc.gov/osels/ph_surveillance/nndss/casedef/lyme_disease_2008.htm