Measles Outbreak at a Privately Operated Detention Facility: Arizona, 2016

Measles Outbreak Associated with a Migrant Shelter - Chicago, Illinois, February-May 2024

Measles, a highly contagious respiratory virus with the potential to cause severe complications, hospitalization, and death, was declared eliminated from the United States in 2000; however, with ongoing global transmission, infections in the United States still occur. On March 7, 2024, the Chicago Department of Public Health (CDPH) confirmed a case of measles in a male aged 1 year residing in a temporary shelter for migrants in Chicago. Given the congregate nature of the setting, high transmissibility of measles, and low measles vaccination coverage among shelter residents, measles virus had the potential to spread rapidly among approximately 2,100 presumed exposed shelter residents. CDPH immediately instituted outbreak investigation and response activities in collaboration with state and local health departments, health care facilities, city agencies, and shelters. On March 8, CDPH implemented active case-finding and coordinated a mass vaccination campaign at the affected shelter (shelter A), including vaccinating 882 residents and verifying previous vaccination for 784 residents over 3 days. These activities resulted in 93% measles vaccination coverage (defined as receipt of ≥1 recorded measles vaccine dose) by March 11. By May 13, a total of 57 confirmed measles cases associated with residing in or having contact with persons from shelter A had been reported. Most cases (41; 72%) were among persons who did not have documentation of measles vaccination and were considered unvaccinated. In addition, 16 cases of measles occurred among persons who had received ≥1 measles vaccine dose ≥21 days before first known exposure. This outbreak underscores the need to ensure high vaccination coverage among communities residing in congregate settings.

Measles IgG Avidity Assay

Measles IgG avidity assays determine the overall strength of molecular binding between measles-specific IgG antibodies and measles virus antigens. Avidity results can distinguish recent from distant measles virus infections. Individuals who are immunologically naïve to measles virus develop low-avidity antibodies upon measles virus infection or first-time vaccination. Within 4-6 months, antibodies mature to high avidity. Measles avidity assays are most useful in the context of measles elimination. In such settings, avidity and epidemiological and clinical information are used to classify measles breakthrough infections for control and surveillance purposes and to assist in case confirmation when other laboratory results are inconclusive or nonexistent. We present a highly accurate end-titer measles avidity assay that delivers results based on IgG quality (avidity) that are independent of IgG concentration.

Management and Control Issues Related to Two Mumps Outbreaks in Houston: Future Implications

BACKGROUND

Mumps is a highly contagious disease spread by airborne droplets, making control especially difficult in congregate, crowded settings such as shelters and jails. A mumps outbreak in Honduras, starting in 2018 among adults who were unvaccinated, spread northward with Central Americans migrating to the United States. We describe 2 mumps outbreaks in Houston during 2019 among migrants at the Houston Contract Detention Facility (HCDF) and among inmates at the Harris County Jail (HCJ).

METHODS

We investigated cases of acute onset parotitis. Three or more mumps cases in a facility was considered an outbreak. Confirmed cases had positive polymerase chain reactions (PCR). Probable cases were linked epidemiologically to a confirmed case in the same unit and a positive serology for serum anti-mumps immunoglobulin M (IgM) antibody. Outbreak control measures included enhanced surveillance, isolation of housing units, educational outreach, and immunization with Measles, Mumps, Rubella (MMR) vaccine.

RESULTS

At HCDF, during a 10-month period, we investigated 42 possible cases. Of the possible cases, 28 were lab-confirmed with 9 probable, 4 ruled out, and 1 vaccine reaction. All were migrants. At HCJ, during a 3-month period, we investigated 60 suspect cases; 20 cases were lab-confirmed, 13 probable and 27 ruled out. All but 2 were inmates. Only about a third of those offered MMR vaccination accepted.

CONCLUSIONS

Successful outbreak resolution required close cooperation with HCDF and HCJ with ongoing surveillance, isolation of units with cases and MMR vaccination. Such facilities will have outbreaks; regular communications with local public health could improve response.

Etiological analysis of discarded measles in the context of a measles outbreak among a highly immunized population

BACKGROUND

Measles can lead to serious complications and remains an important cause of morbidity and mortality worldwide. In this study we aimed to assess the etiological diagnosis of discarded measles cases in the context of an outbreak among a highly immunized population.

METHODS

We conducted a retrospective observational study of discarded measles cases from an outbreak that occurred from October 2006 to July 2007 in Catalonia. A confirmed case was defined as having a positive measles serum IgM result and/or a positive result by RT-PCR in urine and/or nasopharyngeal swab; or an epidemiological link to a confirmed case. Serum specimens were tested by a commercially available indirect-format and by an in-house capture-format measles IgM enzyme immunoassays.

RESULTS

Testing of 89 samples discarded for measles determined the etiologies for 10 (11.2%), including one rubella, three human herpes virus 6, and six measles infections. Of 381 confirmed cases in the outbreak, 10% had received at least one dose of the measles-mumps-rubella vaccine versus 54% of the discarded for measles (OR: 0.09; 95% CI: 0.06, 0.14; p < 0.001).

CONCLUSIONS

Highly sensitive surveillance systems are critical to identifying cases, responding to outbreaks and verifying progress towards measles elimination. Molecular tools for measles detection and differential diagnosis, and collection of appropriate specimens for molecular and serological testing are essential to correctly diagnose suspected measles infection.

Control of a nosocomial measles outbreak among previously vaccinated adults in a population with high vaccine coverage: Korea, 2019

We describe a measles outbreak among previously vaccinated healthcare workers (HCWs) and inpatients and the control measures implemented at a tertiary care hospital in 2019. Case-patients were laboratory-confirmed measles with throat swabs tested by quantitative polymerase chain reactions (PCR), during April-May 2019. Medical histories and documented immunization records were obtained. We compared attack rates (ARs) among HCWs by occupational subgroup and age and examined the outbreak-associated costs. The index case was not ascertained. Among 26 measles case-patients (22 HCWs, four inpatients) aged 18-28 years, 25 had previously received measles-mumps-rubella (MMR) vaccine (12/26, 46% (two doses); 13/26, 50% (one dose)), and 16 (62%) had positive results of measles IgG prior to measles diagnosis. ARs were higher among HCWs aged < 30 years (1.88%), especially in the subgroup under 25 years of age (2.22%). Control measures included work restrictions for seronegative HCWs (218/2320, 9.4%) in immunity verification, administration of the MMR vaccine (207 HCWs) or intravenous immunoglobulin (2 HCWs and 11 inpatients), enhanced health surveillance of HCWs, and mandatory assessment of patients with measles-like symptoms at the infectious diseases screening units. The hospital spent 90,417,132 Korean won (US $79,733) in response to the outbreak. Measles outbreaks can occur in healthcare settings despite high population immunity, highlighting the importance of stronger vaccination policies, particularly among young HCWs. Moreover, an effective outbreak response comprising immunization activities and enhanced surveillance of HCWs and patients to rapidly detect measles-like symptoms at a prodromal phase is essential to control nosocomial measles outbreaks.

Influenza, Varicella, and Mumps Outbreaks in US Migrant Detention Centers

This study uses US Immigration and Customs Enforcement (ICE) Health Service Corps data to describe incident cases and outbreaks of influenza, varicella, and mumps in 22 US ICE detention centers between 2017 and March 2020.

Managing outbreaks of highly contagious diseases in prisons: a systematic review

BACKGROUND

There are reports of outbreaks of COVID-19 in prisons in many countries. Responses to date have been highly variable and it is not clear whether public health guidance has been informed by the best available evidence. We conducted a systematic review to synthesise the evidence on outbreaks of highly contagious diseases in prison.

METHODS

We searched seven electronic databases for peer-reviewed articles and official reports published between 1 January 2000 and 28 July 2020. We included quantitative primary research that reported an outbreak of a given contagious disease in a correctional facility and examined the effects of interventions. We excluded studies that did not provide detail on interventions. We synthesised common themes using the Synthesis Without Meta-analysis (SWiM) guideline, identified gaps in the literature and critically appraised the effectiveness of various containment approaches.

RESULTS

We identified 28 relevant studies. Investigations were all based in high-income countries and documented outbreaks of tuberculosis, influenza (types A and B), varicella, measles, mumps, adenovirus and COVID-19. Several themes were common to these reports, including the public health implications of infectious disease outbreaks in prison, and the role of interagency collaboration, health communication, screening for contagious diseases, restriction, isolation and quarantine, contact tracing, immunisation programmes, epidemiological surveillance and prison-specific guidelines in addressing any outbreaks.

DISCUSSION

Prisons are high-risk settings for the transmission of contagious diseases and there are considerable challenges in managing outbreaks in them. A public health approach to managing COVID-19 in prisons is required.

PROSPERO REGISTRATION NUMBER

CRD42020178827.

Interventions to reduce the burden of vaccine-preventable diseases among migrants and refugees worldwide: A scoping review of published literature, 2006-2018

BACKGROUND

Disparities in vaccine-preventable disease (VPD) burden and immunisation coverage between migrants and refugees and their host populations have been described in numerous countries worldwide. Effective strategies are required to reduce the health disparities and immunisation inequities experienced by migrants and refugees.

METHODS

Using Arksey and O'Malley's framework, we conducted a scoping review to identify available literature on interventions aimed at reducing VPD burden among migrants and refugees worldwide. We searched for relevant empirical, peer-reviewed literature published in English between 2006 and 2018 using MEDLINE, Ovid EMBASE, CINAHL, Sociological Abstracts, and Web of Science databases. Relevant information from the studies, including intervention type, details and outcomes, were charted in Microsoft Excel and results were summarised using a descriptive analytical method.

RESULTS

Seventy studies met the inclusion criteria. The number of published studies increased over the years. The majority of studies were conducted in high-income countries. More studies were conducted among migrants (not including refugees) (n = 48, 66%) than specifically among refugees (n = 25, 34%). Interventions were implemented in a variety of settings, including health care (n = 31, 42%), community (n = 29, 39%), off-shore (n = 7, 9%), national (n = 4, 5%), school (n = 2, 3%), and workplace (n = 1, 1%). Studies reported interventions focused at the individual (to facilitate uptake of health services) (n = 4, 5%), community (to raise awareness) (n = 25, 34%), provider (to offer health services) (n = 12, 16%) and/or system (to increase compliance with recommendations) (n = 33, 45%) level. To be effective, interventions were designed to overcome commonly identified barriers to accessing services related to language, culture, distance and cost. Engagement with community members and organisations was an effective way to co-design interventions that address migrants' specific needs.

CONCLUSIONS

Studies emphasised the importance of interventions that address the heterogeneity within and between migrant and refugee populations. Considerable variation in practice remains, therefore more evaluation of interventions is needed to inform policy and programme decision-making.

Control of measles in a juvenile custodial setting in the wake of the recent US outbreak

The recent US measles outbreak is the largest since 1992. It is just a matter of time before measles is introduced into a juvenile custodial setting. Are we prepared? Should we be prepared? This short article addresses steps institutional settings should take to prevent the spread of measles in a contained setting.