Recent Cryptosporidium Outbreak Changes New Mexico's Mild Trends, 2004-2008

Since 2004, New Mexico has been collaborating with the New Mexico Department of Health and CDC's Emerging Infections Program FoodNet (FN) to perform active, population-based surveillance of selected pathogens, including Cryptosporidium. Analyzing information collected from 2004 to 2008, we found recent NM cryptosporidiosis rates far exceed the Healthy People 2010 goal of a 50% reduction from the 1997 national baseline. From 2004 to 2008, 373 cases of laboratory-confirmed cryptosporidiosis were reported, with 292 (78%) reported for years 2007 and 2008. In 2007, 119 (32%) of case etiologies were unclear; however, some may have reflected state-specific laboratory testing issues and/or missed outbreak/s. In 2008, 173 (46%) of cases reflected a community pool-associated outbreak. For years 2004-2006, FN (10 states) annual rates were 1.4, 2.9, 1.9 per 100,000, respectively, compared to NM-only annual rates of 1.2, 0.9, 1.8 per 100,000 for the same years. However, for years 2007 and 2008, the NM rates increased to 5.9 and 8.7 per 100,000, respectively. Children nineteen years and younger comprised 40% of the cases in 2007, and 54% in 2008. For 2007-2008, 14% of cases were hospitalized and there were no deaths. Higher percentages of cases in 2007 (50%) and in 2008 (52%) were reported from counties classified as metropolitan statistical areas (containing two-thirds of the state's population) compared to only 35% in previous years. The 2008 Cryptosporidium outbreak investigation revealed that revised city and state recreational water- associated goals and guidelines are likely necessary in order to assist in the reduction of cryptosporidiosis