Notes from the Field: Aseptic Meningitis Outbreak Associated with Echovirus 30 Among High School Football Players — Los Angeles County, California, 2014

Curtis Croker, MPH1, Rachel Civen, MD1, Kathleen Keough2, Van Ngo, MPH1, Amy Marutani1, Benjamin Schwartz, MD1 (Author affiliations at end of text)

On August 4, 2014, the Acute Communicable Disease Control Program of the Los Angeles County Department of Public Health received a report of three aseptic meningitis cases among football players at a county high school. An investigation was conducted to determine the extent of the outbreak, identify potential exposures, and recommend control measures. An outbreak-associated aseptic meningitis case was defined as an illness of any team or family member with onset during July 28–August 11 with 1) cerebrospinal fluid pleocytosis and negative bacterial culture or 2) an emergency department visit with headache, fever, and stiff neck. Ten cases were identified; nine in males, and one in a female; patient ages ranged from 13 to 17 years. All the patients sought care at an emergency department, and five were hospitalized, resulting in 12 total hospital days. All 10 patients have recovered. Eight patients were football players, and two were siblings of football players. The most affected subgroup was the junior varsity football team, with seven cases out of 57 players (attack rate = 12.3%); the relative risk for aseptic meningitis was higher among players who were linemen than among those who were not linemen (relative risk = 5.4 [p = 0.03]). Of the 10 patients, eight tested positive by polymerase chain reaction for enterovirus, and two were not tested. Echovirus testing was performed at the California Viral and Rickettsial Disease Laboratory. Of the eight specimens testing positive for enterovirus, seven tested positive for echovirus 30, and one specimen could not be typed because of insufficient quantity.

Echovirus 30 accounted for 4.5% of nonpolio enterovirus serotypes reported in the United States during 2006-2008 (1). Echovirus types 5, 9, 16, and 24 have been associated with aseptic meningitis outbreaks in football teams (2,3). However, this appears to be the first documented echovirus 30 aseptic meningitis outbreak in the United States among members of a sports team.

Investigators from the Acute Communicable Disease Control Program determined the most likely factors resulting in transmission included water bottles shared among football players, inadequate washing of water bottles, and poor hand hygiene. School staff members notified parents of the outbreak and likely mitigated infection sources. Summer football league games between the affected high school and nearby schools posed a risk for spread of infection; however, investigators pursued active case-finding in area hospitals and schools and identified no additional cases. School staff members were asked to encourage proper hand hygiene and discourage shared water bottles to avoid future outbreaks.

1Acute Communicable Disease Control Program, Los Angeles County Department of Public Health, California; 2Office for State, Tribal, Local, and Territorial Support, CDC (Corresponding author: Curtis Croker, ccroker@ph.lacounty.gov, 213-240-7941)

References

1. CDC. Nonpolio enterovirus and human parechovirus surveillance—United States, 2006–2008. MMWR Morb Mortal Wkly Rep 2010;59:1577–80.
2. Turbeville SD, Cowan LD, Greenfield RA. Infectious disease outbreaks in competitive sports. A review of the literature. Am J Sports Med 2006;34:1860–5.
3. Baron RC, Hatch MH, Kleeman K, MacCormack JN. Aseptic meningitis among members of a high school football team: an outbreak associated with echovirus 16 infection. JAMA 1982;248:1724–7.