a1 Centers for Disease Control and Prevention, Atlanta, GA, USA
a2 Unidad de Vigilancia Epidemiologica, Hermosillo, Sonora, Mexico
a3 Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
a4 Dirección General de Epidemiología, Mexico City, Mexico
a5 Servicios de Salud, San Luis Río Colorado, Sonora, Mexico
a6 Yuma County Health Department, Yuma, AZ, USA
a7 Arizona Department of Health Services, Phoenix, AZ, USA
a8 Atlanta Research and Education Foundation, Decatur, GA, USA
In June 2011, a cluster of suspected cases of Guillain–Barré syndrome (GBS), which can follow Campylobacter jejuni infection, was identified in San Luis Río Colorado (SLRC), Sonora, Mexico and Yuma County, Arizona, USA. An outbreak investigation identified 26 patients (18 from Sonora, eight from Arizona) with onset of GBS 4 May–21 July 2011, exceeding the expected number of cases (n = 1–2). Twenty-one (81%) patients reported antecedent diarrhoea, and 61% of 18 patients tested were seropositive for C. jejuni IgM antibodies. In a case-control study matched on age group, sex, ethnicity, and neighbourhood of residence, all Arizona GBS patients travelled to SLRC during the exposure period vs. 45% of matched controls (matched odds ratio 8·1, 95% confidence interval 1·5–∞). Exposure information and an environmental assessment suggested that GBS cases resulted from a large outbreak of C. jejuni infection from inadequately disinfected tap water in SLRC. Binational collaboration was essential in investigating this cross-border GBS outbreak, the first in mainland North America since 1976.
(Received April 15 2013)
(Revised June 25 2013)
(Accepted July 10 2013)
† Additional members of the GBS Outbreak Investigation Team are listed in the Appendix.