BRIEF REPORTS ASSOCIATION OF REGULATORY ISSUES WITH AN ECHOVIRUS 18 MENINGITIS OUTBREAK AT A CHILDREN’S SUMMER CAMP IN ALASKA Joseph B. McLaughlin, MD, MPH,* Bradford D. Gessner, MD, MPH,† Tracey V. Lynn, DVM, MS,† Elizabeth A. Funk, MD, MPH,† and John P. Middaugh, MD† Abstract: We document an echovirus 18 meningitis outbreak oc- curring at a remote overnight children’s camp in Alaska. The outbreak involved 26% of 113 camp residents, was associated with building overcrowding and occurred in a camp with a contaminated drinking water source. Lack of specific children’s camp regulations and failure to implement and enforce existing regulations may have contributed to the outbreak. Key Words: meningitis, outbreak, camp, regulations Accepted for publication April 20, 2004. From the *Epidemic Intelligence Service Program, Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, GA; and the †Division of Public Health, Alaska Department of Health and Social Services, Anchorage, AK Address for reprints: Joseph McLaughlin, MD, MPH, Division of Public Health, Alaska Department of Health and Social Services, 3601 C Street, Suite 540 Anchorage, AK 99503. Fax 907-562-7802; E-mail joe_mclaughlin@health.state.ak.us. Copyright © 2004 by Lippincott Williams & Wilkins DOI: 10.1097/01.inf.0000136867.18026.22 O n August 8, 2001, a physician notified the Alaska Department of Health and Social Services, Section of Epidemiology, of 4 hospitalized children with presumed viral meningitis. During July, all 4 of the children attended a multiweek summer camp, located on an otherwise uninhabited island in Prince William Sound, Alaska. Although camp outbreaks have been frequently reported, 1–3 the existence, compliance with and enforcement of legal guidelines that may have contributed to these outbreaks have not been well- documented. METHODS Retrospective Cohort Study. A primary case of viral meningitis was defined as onset of headache in a camp resident within 21 days of leaving the camp, 4 with at least 2 of the following additional symptoms: photophobia; stiff neck; nausea; self-reported fever or chills; or myalgias. During the second week of August, we con- ducted onsite investigations in 3 communities where case patients were identified after returning home from the camp. We adminis- tered a questionnaire by telephone or in person to all persons who attended the camp during July 9 –30, 2001. For each person inter- viewed, we recorded basic demographic information, illness char- acteristics and information regarding risk factors for illness. Over- crowding was defined as a dwelling that housed 1 occupant per 400 ft 3 , as per Alaska legal standards (18AAC30.410b1). 5 The camp was conducted in three 8-day sessions during July 9 –30. Eighty-nine camp residents (79%) attended 1 session, 5 (4%) at- tended 2 sessions and 19 (17%) attended all 3 sessions. Environmental Investigation. During the first week of September, we visited the camp, obtained measurements and occupancy data for camp dwellings and counted the number of toilets, sinks and showers in bathroom facilities. Water samples from bathroom fau- cets, kitchen faucets, lake water and mountain water runoff were tested for fecal coliform analysis. Testing camp water for echovirus was not feasible because of the remote location of the camp and the high volume of water necessary. In addition, we reviewed the existence and implementation of Alaska state regulations pertaining to children-specific institutions such as schools, day-care facilities and children’s camps. Laboratory Investigation. Clinical samples including cerebrospinal fluid, rectal swabs and nasopharyngeal swabs were collected from a convenience sample of case-patients and sent to the Alaska State Public Health Virology Laboratory for enteroviral isolation and identification. Three viral isolates were forwarded to the Centers for Disease Control and Prevention (CDC) enteroviral laboratory for serotype confirmation. Statistical Analysis. Risk ratios and their Taylor series 95% confi- dence intervals (CI) were calculated using Epi-Info 2000 version 1.1.2 statistical software. 6 SPSS version 11.0.1 statistical software was used for backward stepwise multiple logistic regression analy- sis. 7 Variables with P  0.05 were removed from the model. RESULTS Retrospective Cohort Study of Camp Residents. A total of 113 persons (including students, staff and children of staff) with a median age of 14 years (range, 3 months– 81 years) resided at the summer camp during July 9 –30, 2001. The telephone questionnaire response rate was 100%. Twenty-nine (26%) camp residents met the case definition for viral meningitis. Four (14%) of the case-patients developed symp- toms while at the camp. For the 25 case-patients who became ill after departing the camp, the median time from camp departure to illness onset was 7 days (range, 1–17 days). In addition to headache and nausea or vomiting, symptoms included self-reported feverish- ness or chills (79%), myalgia (55%), photophobia (38%), neck pain (24%) and sonophobia (17%). Seven (24%) case-patients were evaluated in a clinic by a health-care provider, and 5 (17%) were hospitalized; none died or were known to have developed prolonged sequelae. Of 20 camp dwellings, 4 met our definition for being over- crowded during at least 1 of the 3 camp sessions. Twenty-three (79%) of the case-patients at the camp resided in an overcrowded dwelling. Twenty-one (72%) case-patients shared housing with another case-patient at the camp. Bivariate analysis documented that age and living in an overcrowded dwelling were significant risk factors for illness (Table 1). In addition, there was a trend toward higher attack rates for persons attending later camp sessions. With a backward stepwise multiple logistic regression model, which included all bivariate risk factors in Table 1, age 18 years (adjusted odds ratio, 6.9; 95% CI 1.49 –31.79) and residing in an overcrowded dwelling (adjusted odds ratio, 4.1; 95% CI 1.47–11.55) remained independent risk factors for illness. Laboratory Investigation. Specimens were collected from a total of 17 case-patients who attended or were contacts of someone who attended the summer camp. Positive samples were collected from 3 primary and 8 secondary case-patients. Echovirus 18 was isolated from 3 of 3 CSF samples, 7 of 9 rectal swabs and 1 of 15 nasopharyngeal swabs. All 3 of the viral culture isolates sent to the CDC enteroviral laboratory for isolation confirmation were sero- typed as echovirus 18. Environmental Investigation. The original drinking water system was a well, approved by the Alaska Department of Environmental Conservation in May 1998. After increased water usage, the well water volume decreased substantially. Consequently the camp man- The Pediatric Infectious Disease Journal • Volume 23, Number 9, September 2004 875