Rapid Implementation of Universal MMR Vaccination to Control a Mumps Outbreak at a U.S. Immigration and Customs Detention Facility in Colorado

The goal and objectives of this emergent public health response were to manage the outbreak of mumps within the facility, end the ongoing transmission of mumps amongst detainees, prevent mumps transmission into the community, and develop solutions to prevent future mumps outbreaks at the Aurora facility. Controlling a mumps outbreak and implementing novel practices such as universal MMR vaccination required strong collaboration between TCHD, CDPHE, CDC and ICE federal partners, and facility leadership, health services staff, and corporate liaisons. At the time of initial outbreak notification, CDPHE took immediate steps, in coordination with TCHD, to contact the facility's leadership to review disease-reporting requirements, initiate disease surveillance and control methods, and recommend universal vaccination of all facility detainees and staff. Sharing standard public health outbreak recommendations for case ascertainment, isolation, and quarantine was an important component of disease control. But alone, those steps were not sufficient to successfully curb the outbreak in the detention center given the high proportion of mumps-susceptible detainees and detainee movement into and out of the facility. To establish a foundation of trust, TCHD facilitated a carefully coordinated on-site facility visit with representatives from public health, local facility leadership and health services staff, and (importantly) out-of-state corporate senior medical staff. Implementation of a mass MMR vaccination program and sustaining vaccination along with other disease control efforts required an understanding of the facility's layout, capacity, and limitations. Administering vaccine to 1140 detainees (plus new arrivals) and 219 staff was a monumental task. The resources needed to undertake a universal vaccination program required buy-in not only from facility leadership, but from their corporate liaisons and federal partners. Bulk vaccine for detainees was sourced through ICE Health Services Corp, and TCHD provided hands-on, customized support from our epidemiologists, medical epidemiologist, and immunization nurses. Training and references were provided to properly store and handle vaccine, educate detainees to obtain voluntary consent, screen for medical contraindications, document doses administered, and manage data so vaccination rates could be tracked. Within one week of sharing detailed recommendations and completing our on-site visit, mass vaccination began and by the following week 85% of detainees had been vaccinated.

During the first few weeks of the outbreak, TCHD and CDPHE worked with the facility daily or several days per week to ensure recommendations were being followed. We collaboratively addressed the feasibility and logistics of case identification, reporting to public health, testing of ill detainees, isolation, quarantine, and vaccination. Public health recommendations were outlined verbally and in writing to ensure our guidance was clearly communicated and understood. Our advocacy and direct outreach with corporate leadership made evident the importance of providing additional resources to support on-site surveillance and vaccination efforts. The facility's buy-in for disease control was robust. Corporate liaisons provided necessary staffing resources and vaccine was promptly sourced. Facility health services staff independently held ‘town-hall meetings' in each housing unit to share information and educate detainees about the voluntary MMR vaccination efforts. While facility staff led efforts to vaccinate their detainee population, TCHD immunization nurses concurrently worked to vaccinate 219 facility staff. TCHD utilized government-funded 317 vaccine to offer an outbreak dose of MMR vaccine at no cost to staff.

A formal cost benefit analysis was unable to be performed for this outbreak response. However, estimates of the burden and resources required for outbreak control included:

• During February – April 2019, daily/weekly/biweekly communication (hours of phone calls, conference calls, emails) between TCHD epidemiologists (1-2) and medical epidemiologist; CDPHE vaccine-preventable disease epidemiologists (2-3) and Colorado's state epidemiologist; facility medical director, health services administrator, warden, and deputy warden; facility's corporate chief medical officer, vice president health services, regional health services manager, and chief of nursing; and ICE Health Services Corp field office medical coordinator and federal chief of public health, safety and preparedness unit.
• TCHD resources for vaccination clinics at the facility on multiple occasions:  TCHD's Immunization Program provided FTE and supplies to support five on-site vaccination clinics for staff — requiring 2-5 public health nurses and 1-2 clerical staff per clinic, and clinics lasted 4-5 hours each to administer between 20-100 doses of MMR vaccine. Additionally, TCHD provided nursing and clerical support for three ad hoc detainee vaccination clinics during May - June 2019.
• During May through September 2019, ad hoc time commitment from TCHD's lead outbreak epidemiologist and medical epidemiologist to respond to sporadic mumps cases and sustain vaccination efforts. 
• The facility's initial procurement of 1170 doses of MMR vaccine (federal cost not available, but local public health governmental cost is approximately $40 per dose). Subsequent procurement of hundreds of additional vaccine doses from ICE to sustain vaccination efforts.
• All public health resource commitments were in-kind. As a provisional estimate, TCHD epidemiology staff spent approximately 190 person-hours working with the facility and public health partners to prepare, develop, and implement the rapid universal vaccination program. Additionally, TCHD immunization nurses and clerical staff spent approximately 160 person-hours preparing for and administering MMR vaccine to the facility's staff.
  

Our partnership and collaborative efforts spanned beyond the last mumps case in early March and past the conclusion of the outbreak in late April. TCHD and facility leadership continued to work together to monitor for and promptly respond to new, sporadic mumps cases and to sustain universal detainee vaccination for several months through September 2019. Public health support and advocacy were instrumental for liaising with the facility's corporate leaders to maintain resources for vaccination. Clear and open communication, transparency, and advocacy were key to establishing an effective partnership between multiple public health agencies, the facility, and other stakeholders. In addition to meeting the shared goal and objectives to end the mumps outbreak, we set a precedent and created a strong foundation to address public health incidents in the future.

TCHD and CDPHE worked collaboratively 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 1, 2019, CDPHE received the initial report of mumps in a detainee at the Aurora ICE facility. CDPHE made initial contact with the facility to review the disease-reporting requirements and disease control measures. After those communications, it was apparent there was an outbreak of mumps at the facility and TCHD then served as lead of the investigation. Formal written recommendations prepared by TCHD and CDPHE were presented to the facility re-emphasizing best practices for enhanced surveillance, disease reporting, laboratory testing, isolation, quarantine, and universal vaccination. Over the next several weeks, TCHD and CDPHE engaged in daily/weekly/biweekly communication with the facility leadership, health services staff, and corporate liaisons to build trust, provide updated recommendations, and set up a mass vaccination program. By February 22, 2019, the facility received approximately 1170 doses of MMR vaccine from ICE Health Services Corp for universal vaccination of detainees. Prior to initiating vaccination, TCHD immunization nurses provided guidance regarding vaccine storage and handling, obtaining voluntary consent, screening for medical contraindications, and properly documenting administered doses.

Vaccination outcomes were tracked in facility medical records for detainees and by TCHD for vaccine administered to facility staff.

• During February 25 March 1, 2019, facility health services staff offered MMR vaccine to 1348 detainees, of which 1140 (85%) received a dose. Seventeen (57%) of the 30 housing units had MMR vaccine uptake ranging from 90-100% during the first five days of vaccination efforts.
• During February 28 March 20, 2019 simultaneous staff vaccination conducted by TCHD yielded high vaccination uptake; 219 (81%) of the 270 facility staff received MMR vaccine.

Surveillance for mumps cases was conducted by TCHD and CDPHE using standard protocols for case investigation and data were monitored in Colorado's electronic disease reporting system.

• Prior to vaccination efforts, there was evidence of ongoing mumps exposure and transmission within the quarantined housing units. In total, 15 outbreak cases of mumps (13 confirmed cases and two probable cases) were reported and no community cases were identified. Of the 15 cases, 13 (87%) were detainees and two (13%) were facility staff. Fourteen of the 15 cases were male. Case ages ranged from 20 to 50 years old (median 26 years). Case onset dates of salivary gland swelling ranged from January 9 March 9, 2019. Four (13%) of the 30 housing units at the facility were impacted by one or more mumps cases and were placed in quarantine after a case was identified. Two housing units had one or two generations of new cases with incubation periods ranging between 14 to 20 days. One case was hospitalized and there were no deaths associated with the outbreak.
• Once universal MMR vaccination was implemented, achieving high facility-wide vaccination rates likely interrupted transmission and led to the expeditious end of the mumps outbreak. The illness onset date of the last mumps case was on March 9, 2019, which occurred 12 days after universal MMR vaccination efforts began. 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.
• The outbreak which was officially declared to have ended on April 29, 2019, following two full mumps incubation periods with no new cases.
• As mumps cases among detainees in ICE detention facilities continued to increase across the country, TCHD and facility leadership recognized the risk of future outbreaks from introduction of new mumps cases into the facility. The stakeholder group managing the outbreak agreed that sustained vaccination efforts were the best method to mitigate this risk. During and after the outbreak, MMR vaccine was offered to incoming detainees within 72 hours of initial intake. From March through September 2019, facility-wide detainee vaccination rates ranged from 55-85%. While the vaccination rate fluctuated over time, the facility did not have any subsequent outbreaks of mumps even though four additional sporadic cases were identified during May 20 October 7, 2019.

Modification of practices post universal vaccination. Prior to implementing mass vaccination, the facility's primary disease control method was to quarantine housing units with a mumps case for a full incubation period (25 days) after the last exposure to the mumps case. Furthermore, the 25-day quarantine period would be reset if new cases of mumps arose within the same housing unit. To prevent transmission in other areas of the facility, detainees in quarantine were restricted from moving outside of the housing unit, they preferably were not transferred, and no new detainees were permitted to be housed in a quarantined unit. However, it became evident that challenges were arising regarding visitation and access to legal services, particularly for detainees who might have been placed in extended periods of quarantine. Recognizing these were important issues for social and legal support, TCHD took another innovative approach to address these challenges. Once universal MMR vaccination was well established for detainees and staff, facility-wide vaccination rates were high, and mumps cases markedly declined, TCHD worked with CDPHE, CDC, and the facility to revise quarantine recommendations. Detainees who received a documented MMR vaccine were not required to remain in quarantine even if a case of mumps was introduced into their housing unit. Vaccinated detainees living in quarantined housing units were permitted movement throughout the facility to access social and legal services under specific criteria (e.g., symptom screening, proper disinfection and cleaning, etc). These adapted quarantine recommendations proved to be highly beneficial for detainees and less disruptive to the facility's operations for managing detainee services.

The Aurora ICE facility was the first in the U.S. to proactively offer an outbreak dose of MMR vaccine to all detainees and staff as a primary disease control measure. As a novel and innovative practice in this setting, universal vaccination proved to be a highly effective method to rapidly curb the outbreak of mumps in a highly susceptible population, while also mitigating risk of disease spillover into the community. Sustained vaccination efforts prevented subsequent outbreaks even as new sporadic cases of mumps were introduced into the facility. Up to the present time, we have streamlined communication between TCHD, CDPHE, and the facility to promptly respond to any new detainee suspected of having mumps. TCHD will quickly work with facility health services staff to clinically assess the detainee, submit a sample for testing at the CDPHE laboratory, implement active surveillance for additional cases, and determine appropriate disease control measures including a reassessment of detainee vaccination rates. It was critical for public health to look beyond the standard, conventional methods of outbreak response given the novel setting and unique population. Gaining a better understanding of the facility's infrastructure, organization, population, capabilities, and limitations were essential to achieve our public health objectives while also setting the facility up for success for outbreak mitigation. The response brought together multiple disciplines, areas of expertise, and perspectives that worked collaboratively towards a shared goal. Providing education on the role of public health and key principles of disease control, including disease reporting, enhanced surveillance, isolation, quarantine, immunizations, etc., were critical first steps in fostering a partnership and cooperative approach.  Beyond the immediate efforts to control the outbreak, the lasting relationships, trust, and collaboration between public health, the facility, and surrounding stakeholders were true measures of sustainability. We feel confident in our ability to effectively and efficiently address future public health incidents that may occur at the facility as a result of the partnerships established during this response. We encourage other public health agencies in jurisdictions with facility-associated mumps outbreaks to engage with facility leadership to strengthen relationships and explore universal vaccination.