2009-2010 Recreational Water-associated Outbreak Surveillance Report Supplemental Tables

These tables provide supplemental information not published in Recreational Water–Associated Disease Outbreaks — United States, 2009–2010 (MMWR Weekly).

TABLE 1. Waterborne Disease Outbreaks Associated with Treated Recreational Water (n = 57) and Untreated Recreational Water (n = 24), by Year and Jurisdiction — Waterborne Disease and Outbreak Surveillance System, United States, 2009–2010

Treated Recreational Water

Untreated Recreational Water

Abbreviations: AGI = acute gastrointestinal illness; ARI = acute respiratory illness; Ear = illnesses, conditions, or symptoms related to the ears; Eye = illnesses, conditions, or symptoms related to the eyes; Neuro = neurologic illnesses, conditions, or symptoms (e.g., meningitis); Skin = illnesses, conditions, or symptoms related to the skin.

* Based on epidemiologic, clinical laboratory, and environmental data (e.g., water quality data) reported to CDC. For more information, refer to the strength-of-evidence classification table.

† The category of illness reported by ≥50% of ill respondents. All legionellosis outbreaks were categorized as ARI.

§ No outbreak-related deaths were reported.

¶ Value was set to missing in reports when zero hospitalizations were reported and the reported number of people for whom these data were available was also zero.

** Etiology unidentified: Pseudomonas aeruginosa suspected based on reported venue(s) of exposure and clinical signs and symptoms.

†† Cryptosporidium was detected in stool specimens from multiple case-patients. Isolate from one case-patient was identified as Cryptosporidium hominis IaA28R4.

§§ Eleven case-patients reported earaches in addition to dermatologic symptoms.

¶¶ Etiology unidentified: chlorine (i.e., toxic chlorine gas or extremely elevated chlorine levels) suspected based on reported events.

*** Etiology unidentified: disinfection by-products (e.g., chloramines), altered water chemistry, or extremely elevated chlorine levels suspected based on reported data.

††† Isolates from stool specimens of six case-patients were identified as C. hominis IaA28R4; the isolate from another case-patient was identified as C. hominis IaA24R4; and the isolate from another case-patient was identified as C. hominis IdA15G1.

§§§ Etiology unidentified: norovirus suspected based on reported incubation period, symptoms, or duration of illness.

¶¶¶ Eight case-patients reported earaches in addition to dermatologic symptoms.

**** Pool is a manufactured venue that is filled with filtered but otherwise untreated hot spring water.

†††† Etiology unidentified: avian schistosomes suspected based on reported clinical diagnosis of cercarial dermatitis and environmental data.

§§§§ Etiology unidentified: copper suspected based on reported use of chemical treatment for algae.

¶¶¶¶ Etiology unidentified: cyanobacterial toxin(s) suspected based on reported clinical signs and symptoms, environmental data (e.g., confirmed algal bloom), and venue of exposure.

***** Microcystin toxin (≥20 ppb) detected in water samples collected during or within 1 day of dates of exposure. Other cyanobacterial toxin(s) suspected based on reported clinical signs and symptoms.

††††† Microcystin toxin (≥20 ppb), anatoxin-a, saxitoxin, and cylindospermopsin detected in water samples collected during or within 1 day of dates of exposure.

§§§§§ Microcystin toxin (≥20 ppb) detected in water samples collected during or within 1 day of dates of exposure.

¶¶¶¶¶ Etiology unidentified: microcystin toxin, saxitoxin, and other cyanobacterial toxin(s) suspected based on reported clinical signs and symptoms, environmental data (e.g., confirmed algal bloom), and venue of exposure. Microcystin toxin (<20 ppb) and saxitoxin detected in water samples collected during or within 1 day of dates of exposure.

****** Etiology unidentified: microcystin toxin, anatoxin-a, and other cyanobacterial toxin(s) suspected based on reported clinical signs and symptoms, environmental data (e.g., confirmed algal bloom), and venue of exposure. Microcystin toxin (<20 ppb) and anatoxin-a detected in water samples collected during or within 1 day of dates of exposure.

†††††† One or more case-patients reported symptoms in each illness category; however, no illness category was definitively reported by ≥50% of ill respondents. Therefore, all reported illness categories have been included.

§§§§§§ Etiology unidentified: microcystin toxin, anatoxin-a, and cylindrospermopsin suspected based on reported clinical signs and symptoms, environmental data (e.g., confirmed algal bloom), and venue of exposure. Microcystin toxin (<20 ppb), anatoxin-a, and cylindrospermopsin detected in water samples collected during or within 1 day of dates of exposure.

¶¶¶¶¶¶ Etiology unidentified: microcystin toxin based on reported clinical signs and symptoms, environmental data (e.g., confirmed algal bloom), and venue of exposure. Microcystin toxin (<20 ppb) detected in water samples collected during or within 1 day of dates of exposure.

Note: For more detailed information on harmful algal bloom–associated outbreaks, refer to Algal Bloom–Associated Disease Outbreaks Among Users of Freshwater Lakes — United States, 2009–2010 (MMWR Weekly).

 Top of Page

Table 2. Number of Waterborne Disease Outbreaks Associated with Recreational Water (n = 81*), by Predominant Illness† and Type of Water Exposure — Waterborne Disease and Outbreak Surveillance System, 2009–2010

Abbreviations: AGI = acute gastrointestinal illness; ARI = acute respiratory illness; Ear = illnesses, conditions, or symptoms related to the ears; Eye = illnesses, conditions, or symptoms related to the eyes; Neuro = neurologic illnesses, conditions, or symptoms (e.g., meningitis); Skin = illnesses, conditions, or symptoms related to the skin.

* No outbreak-related deaths were reported.

† The category of illness reported by ≥50% of ill respondents. All legionellosis outbreaks were categorized as ARI.

§ One or more case-patients reported symptoms in each illness category; however, no illness category was definitively reported by ≥50% of ill respondents. Therefore, all reported illness categories have been included.

 Top of Page