1617. Mumps in Detention Facilities that House Detained Migrants—United States, September 2018–April 2019

Abstract Background Starting in September 2018, an unusually high number of mumps cases were reported in US adult detention facilities. Detention facilities usually involve close contact among detainees, facilitating transmission of mumps. Detainees in close contact with a mumps patient are at increased risk for acquiring mumps and should be offered a dose of MMR vaccine. We summarize the epidemiologic, clinical, and laboratory data for mumps cases in adult detention facilities during September 2018-April 2019. Methods Data were collected by health departments and US Immigration and Customs Enforcement (ICE) Health Services Corps and reported to CDC. Cases were classified according to the CSTE case definition for mumps and confirmed by RT-qPCR; molecular sequencing was performed on mumps-positive specimens. Results From September 2018-April 2019, 389 confirmed and probable mumps cases in adult migrants detained by ICE in 44 detention facilities were reported in 16 states (figure). The median age of patients was 24 years (range: 18–66); 94% were male. Vaccination status was unknown for all patients. Most (80%) patients were exposed while in custody of ICE or other US legal agency, 7% were exposed before apprehension, and custody status at exposure was unknown for 13%. Among 265 patients with data on complications, 15% had orchitis; at least 3 were hospitalized. Mumps genotype G, the most common genotype in US, was identified in specimens from 70 patients. This mumps response included >7,000 MMR vaccine doses distributed to affected facilities, and hundreds of exposed detainees placed under restricted movement in their facility each week. The response is ongoing as new cases continue to be reported. Conclusion This is the first report of mumps outbreaks occurring in multiple states and detention facilities during the same period. These outbreaks are costly and challenging to control. Identifying target groups for vaccination is challenging since detainees are frequently transferred and MMR vaccine does not prevent mumps in persons already exposed and infected. Effective public health interventions require an understanding of detention settings. Development of national guidance and resources for public health response to mumps and other infectious diseases in detention facilities would be beneficial. Disclosures All authors: No reported disclosures.