Tri-County Health Department (TCHD) serves over 1.5 million people in Adams, Arapahoe, and Douglas Counties across 3,000 square miles in the Denver metropolitan area. TCHD's jurisdiction contains urban, suburban, and rural agricultural designations within 26 municipalities and three unincorporated counties; our county's neighborhoods are demographically and economically diverse.
From September 2018 - September 2019, mumps outbreaks occurred in U.S. Immigrations and Customs Enforcement (ICE) detention facilities in 20 states, with approximately 1000 mumps cases reported among adult migrants in ICE custody. Controlling these ongoing outbreaks of mumps within detention facilities posed unique and novel challenges to local, state, and federal public health agencies.
On February 1, 2019, CDPHE received an initial report of one mumps case in a detainee at the ICE Processing Center in Aurora, Colorado (hereto referred to as the ‘facility'). The Aurora facility is privately owned and contracts with ICE to house approximately 1500 detainees. CDPHE and TCHD determined that this private facility fell under state and local, not federal, public health jurisdiction for disease control purposes. Control of infectious diseases are inherently challenging in detention facilities where prolonged daily contact between detainees, close living quarters, and potential environmental contamination amplifies the risk of ongoing transmission.
More mumps cases ensued. TCHD and CDPHE conducted a joint investigation to achieve our goal of mumps outbreak control and accomplish four objectives 1) manage the mumps outbreak within the facility to prevent spillover into the surrounding community; 2) employ universal measles, mumps, rubella (MMR) vaccination as a primary disease control method; 3) end ongoing transmission of mumps among detainees at the facility; and 4) develop sustainable processes to mitigate the risk of future mumps outbreaks. On February 5, 2019, public health first recommended universal MMR vaccination for all detainees and facility staff. TCHD and CDPHE maintained daily communication to build trust with facility leadership, health services staff, and corporate liaisons and implement outbreak control measures, including setting up a universal vaccination program. Public health promptly instituted isolation of detainees with mumps and quarantine of exposed detainees, but in-facility transmission continued along with importation of new cases. On February 25, 2019, facility health services staff began a universal MMR vaccination program for all detainees. Concurrently, TCHD held five on-site vaccine clinics to provide an outbreak dose of MMR vaccine to staff using federally-funded vaccine for outbreak response. Within five days of implementing the detainee universal vaccination program, MMR vaccine was offered to all 1348 detainees, of which 1140 (85%) detainees received a dose. During February 28 March 20, 2019, 219 (81%) of 270 facility staff received vaccine from TCHD (other staff found previous vaccination records or elected to receive a vaccine from a private health care provider). According to the CDC, during this time period the Aurora facility was the first and only detention facility nationally to initiate universal MMR vaccination as a primary mumps outbreak control measure.
In total, 15 outbreak cases of mumps were reported and no community cases were identified. The illness onset date of the last mumps case was on March 9, 2019, which occurred 12 days after universal MMR vaccination efforts began — clearly demonstrating the impact and success of mass vaccination to curb the outbreak. However, since new detainees with sporadic mumps disease were expected to enter the facility at any time, sustaining high rates of MMR vaccination was necessary to prevent further disease spread. TCHD supported facility efforts to continue offering MMR vaccine to new incoming detainees. During February 25 April 29 (when the outbreak was officially declared over after two incubation period with no cases), detainee MMR vaccination rates were maintained between 55-85%.
Public health's objectives were met — rapid implementation of universal MMR vaccination for detainees and staff controlled the mumps outbreak in the facility within 2 weeks, prevented disease spread into the community, and sustained outbreak control for several months. TCHD and CDPHE communicated our success with CDC and other states facing similar outbreak scenarios in ICE detention centers, and strongly encouraged mass vaccination to curb outbreaks. Vaccination maintained herd immunity and mitigated the risk of mumps among this mobile population, as many detainees were transferred between ICE facilities. Addressing a mumps outbreak in a private ICE Processing Center required strong partnership between state and local public health, federal ICE partners, and the facility's leadership, health services staff, and corporate liaisons. Clear and open communication, transparency, and advocacy were key to establishing an effective collaboration with the facility.
Information on the communicable disease epidemiology program can be found on our website at: www.tchd.org/515/Infectious-Disease-Prevention.