Impact of Isolation and Exclusion as a Public Health Strategy to Contain Measles Virus Transmission During a Measles Outbreak.

Responding to measles outbreaks in the United States puts a considerable strain on public health resources, and limited research exists about the effectiveness of containment strategies. In this paper we quantify the impact of isolation, contact tracing, and exclusion in reducing transmission during a measles outbreak in an under-vaccinated community.

Demographic and Clinical Characteristics of Mpox in Persons Who Had Previously Received 1 Dose of JYNNEOS Vaccine and in Unvaccinated Persons - 29 U.S. Jurisdictions, May 22-September 3, 2022.

As of November 14, 2022, monkeypox (mpox) cases had been reported from more than 110 countries, including 29,133 cases in the United States.* Among U.S. cases to date, 95% have occurred among males (1). After the first confirmed U.S. mpox case on May 17, 2022, limited supplies of JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic) were made available to jurisdictions for persons exposed to mpox. JYNNEOS vaccine was approved by the Food and Drug Administration (FDA) in 2019 as a 2-dose series (0.5 mL per dose, administered subcutaneously) to prevent smallpox and mpox disease.† On August 9, 2022, FDA issued an emergency use authorization to allow administration of JYNNEOS vaccine by intradermal injection (0.1 mL per dose) (2). A previous report on U.S. mpox cases during July 31-September 3, 2022, suggested that 1 dose of vaccine offers some protection against mpox (3). This report describes demographic and clinical characteristics of cases occurring ≥14 days after receipt of 1 dose of JYNNEOS vaccine and compares them with characteristics of cases among unvaccinated persons with mpox and with the vaccine-eligible vaccinated population in participating jurisdictions. During May 22-September 3, 2022, among 14,504 mpox cases reported from 29 participating U.S. jurisdictions,§ 6,605 (45.5%) had available vaccination information and were included in the analysis. Among included cases, 276 (4.2%) were among persons who had received 1 dose of vaccine ≥14 days before illness onset. Mpox cases that occurred in these vaccinated persons were associated with lower percentage of hospitalization (2.1% versus 7.5%), fever, headache, malaise, myalgia, and chills, compared with cases in unvaccinated persons. Although 1 dose of JYNNEOS vaccine offers some protection from disease, mpox infection can occur after receipt of 1 dose, and the duration of protection conferred by 1 dose is unknown. Providers and public health officials should therefore encourage persons at risk for acquiring mpox to complete the 2-dose vaccination series and provide guidance and education regarding nonvaccine-related prevention strategies (4).

Identifying Vaccine-associated Rash Illness Amidst a Large Measles Outbreak: Minnesota, 2017.

Characteristics of vaccine-associated rash illness (VARI) and confirmed measles cases were compared during a measles outbreak. Although some clinical differences were noted, measles exposure and identification of the vaccine strain were helpful for public health decision-making. Rapid, vaccine strain-specific diagnostic assays will more efficiently distinguish VARI from measles.

Measles Outbreak - Minnesota April-May 2017.

On April 10, 2017, the Minnesota Department of Health (MDH) was notified about a suspected measles case. The patient was a hospitalized child aged 25 months who was evaluated for fever and rash, with onset on April 8. The child had no history of receipt of measles-mumps-rubella (MMR) vaccine and no travel history or known exposure to measles. On April 11, MDH received a report of a second hospitalized, unvaccinated child, aged 34 months, with an acute febrile rash illness with onset on April 10. The second patient's sibling, aged 19 months, who had also not received MMR vaccine, had similar symptoms, with rash onset on March 30. Real-time reverse transcription-polymerase chain reaction (rRT-PCR) testing of nasopharyngeal swab or throat specimens performed at MDH confirmed measles in the first two patients on April 11, and in the third patient on April 13; subsequent genotyping identified genotype B3 virus in all three patients, who attended the same child care center. MDH instituted outbreak investigation and response activities in collaboration with local health departments, health care facilities, child care facilities, and schools in affected settings. Because the outbreak occurred in a community with low MMR vaccination coverage, measles spread rapidly, resulting in thousands of exposures in child care centers, schools, and health care facilities. By May 31, 2017, a total of 65 confirmed measles cases had been reported to MDH (Figure 1); transmission is ongoing.

An Assessment of the Cocooning Strategy for Preventing Infant Pertussis-United States, 2011.

BACKGROUND: Infants are at greatest risk for severe pertussis. In 2006, the Advisory Committee on Immunization Practices recommended that adolescents and adults, especially those with infant contact, receive a single dose of Tdap (tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine). To assess the effectiveness of cocooning, we conducted a case-control evaluation of infant close contacts. METHODS: Pertussis cases aged <2 months with onset between 1 January 2011 and 31 December 2011 were identified in Emerging Infections Program Network sites. For each case, we recruited 3 controls from birth certificates and interviewed identified adult close contacts (CCs) or parents of CCs aged <18 years. Pertussis vaccination was verified through medical providers and/or immunization registries. RESULTS: Forty-two cases were enrolled, with 154 matched controls. Around enrolled infants, 859 CCs were identified (600 adult and 259 nonadult). An average of 5.4 CCs was identified per case and 4.1 CCs per control. Five hundred fifty-four (64.5%) CCs were enrolled (371 adult and 183 non-adult CCs); 119 (32.1% of enrolled) adult CCs had received Tdap. The proportion of Tdap-vaccinated adult CCs was similar between cases and controls (P = .89). The 600 identified adult CCs comprised 172 potential cocoons; 71 (41.3%) potential cocoons had all identified adult CCs enrolled. Of these, 9 were fully vaccinated and 43.7% contained no Tdap-vaccinated adults. The proportion of fully vaccinated case (4.8%) and control (10.0%) cocoons was similar (P = .43). CONCLUSIONS: Low Tdap coverage among adult CCs reinforces the difficulty of implementing the cocooning strategy and the importance of vaccination during pregnancy to prevent infant pertussis.

Notes from the Field: Measles Transmission in an International Airport at a Domestic Terminal Gate--April-May 2014.

On April 22, 2014, the Minnesota Department of Health notified CDC of a case of measles in a child aged 19 months who had documentation of receiving 1 dose of measles, mumps, and rubella vaccine at age 12 months. The child's illness was clinically compatible with measles, which was confirmed by polymerase chain reaction and immunoglobulin M serology at the Minnesota Department of Health Public Health Laboratory. The child was febrile and developed a rash on April 17 while on an international flight from India to the United States before taking a connecting flight from Chicago to Minneapolis. Persons with measles are infectious from 4 days before to 4 days after rash onset. Therefore, travelers were exposed on both the international and domestic flights. CDC's Division of Global Migration and Quarantine was contacted and provided information on potentially exposed persons to relevant health departments for follow-up. No documented transmission was reported as a result of the two flight exposures.

Assessing the impact of a pertussis active surveillance program on provider testing behavior, Minnesota 2005-2009.

OBJECTIVES: The Minnesota Department of Health, in collaboration with the Centers for Disease Control and Prevention, implemented the Pertussis Active Surveillance Project to better understand pertussis epidemiology. We evaluated the program's impact. METHODS: Clinics in 2 counties were offered free diagnostic testing and an educational presentation covering pertussis epidemiology. Clinics were identified as either active or intermittent, with active clinics testing 33% or more of the total number of months enrolled. We used generalized estimating equations to assess changes in provider testing behavior over the project period. RESULTS: Ninety-seven clinics enrolled, with 38% classified as active. Active clinics were more likely to use the state lab for diagnostic testing and had a larger staff. During the project period, a decline in days coughing at the time of visit occurred in both jurisdictions. CONCLUSIONS: Providing clinics with free diagnostic testing influenced their participation levels. Among active clinics, results suggest changes in provider testing behavior over the course of the project. However, given the lack of robust participation, this resource-intensive strategy may not be a cost-effective approach to evaluating trends in pertussis epidemiology.

Public health responses during measles outbreaks in elimination settings: Strategies and challenges.

In late September 2016, the Americas became the first region in the world to have eliminated endemic transmission of measles virus. Several other countries have also verified measles elimination, and countries in all six World Health Organization regions have adopted measles elimination goals. The public health strategies used to respond to measles outbreaks in elimination settings are thus becoming relevant to more countries. This review highlights the strategies used to limit measles spread in elimination settings: (1) assembly of an outbreak control committee; (2) isolation of measles cases while infectious; (3) exclusion and quarantining of individuals without evidence of immunity; (4) vaccination of susceptible individuals; (5) use of immunoglobulin to prevent measles in exposed susceptible high-risk persons; (6) and maintaining laboratory proficiency for confirmation of measles. Deciding on the extent of containment efforts should be based on the expected benefit of reactive interventions, balanced against the logistical challenges in implementing them.

Comparison of defects identified through Minnesota's Birth Defects Information System And Vital Records, 2006-2008.

The purpose of this study was to examine the differences in birth defects identified through passive and active surveillance systems in Hennepin and Ramsey counties in Minnesota, 2006-2008. This was done by comparing birth defects identified on birth certificates through the Minnesota Department of Health's Office of the State Registrar's Birth and Death Registry (vital records) with those identified by the Minnesota Department of Health's Birth Defects Information System (BDIS), an active birth defects surveillance system. The study population included 73,059 babies born to residents of Hennepin and Ramsey counties. There were 1,882 babies that either vital records and/or BDIS identified as having 1 or more birth defects. Cases identified by BDIS were then linked with matching birth certificates found in the vital records database. Using BDIS as the gold standard, it was observed that the vital records database had an overall underreporting rate of 89% when all broad groups of defects were compared, and 72% when 11 specific defects tracked by both registries were compared. The sensitivity and positive predictive values of vital records to identify cases were also compared using BDIS as the gold standard, and demonstrated low sensitivities for most of the 11 comparable defects (range: 0% for tracheoesophageal fistula to 80% for anencephalus). These observations indicate that BDIS has significantly improved the quality of birth defects surveillance in Minnesota.