Abstract
Outbreaks of measles increased in the United States in 2019. Occupational health nurses need to be aware of this highly infectious disease, disseminate accurate information, and emphasize the benefits of immunization to workers.
Beginning January 1 to September 12, 2019, the Centers for Disease Control and Prevention (CDC) confirmed 1,250 individual cases of measles in 31 states—the highest number in nearly three decades. More than 75% of the cases are linked to outbreaks in New York, and most cases were among people not immunized; measles spreads where groups of people lack immunizations (CDC, 2019). An outbreak is defined as three or more cases and ends after two incubation periods with no new cases.
Although outbreaks in the United States ended in September, measles remain common in many parts of the world. Outbreaks may occur when international travelers with the disease enter the country, or when unimmunized workers traveling abroad for business or pleasure contract measles while abroad and bring the disease back home (CDC, 2019). Measles is caused by a single-stranded, enveloped RNA virus, and humans are its only natural hosts. The virus stays on surfaces and in the air for up to 2 hours and causes a highly contagious respiratory disease primarily spread by coughing or sneezing. If one person has measles, up to nine of 10 susceptible people will be infected (CDC, 2019).
Prodromal symptoms include fever, cough, coryza, and conjunctivitis. Two to three days after symptoms begin, tiny white spots (Koplik’s spots) may appear inside the mouth (CDC, 2019). A maculopapular rash begins at the hairline and face and spreads downward to the neck, trunk, and extremities; measles is contagious 4 days before and 4 days after the rash appears, which lasts approximately 6 days (CDC, 2019). People at highest risk for measles include infants and children under age 5 years, adults over age 20 years, pregnant women, and people with compromised immune systems. Common complications include otitis media, bronchopneumonia, laryngotracheobronchitis, and diarrhea (CDC, 2019).
As a vaccine-preventable disease, measles immunizations are given in combination with those for mumps and rubella (MMR; The College of Physicians of Philadelphia, History of Vaccines, 2019). MMR is safe and two doses are about 97% effective at preventing measles; one dose is 93% effective (CDC, 2019). The CDC recommends adults born after 1956 receive at least one MMR dose if they never had measles or never been vaccinated against measles (https://www.cdc.gov/vaccines/vpd/mmr/hcp/recommendations.html). Health care personnel, students at post-secondary schools, and international travelers should receive two doses (CDC, 2019). A blood test can confirm immunity when uncertain of vaccination status, or workers can safely get another dose. Laboratory confirmation information is available at https://www.cdc.gov/measles/lab-tools/serology.html. Immunization contraindications include a history of severe allergic reaction to any part of the vaccine, pregnancy, and immunosuppression. Post-exposure MMR vaccine and use of immunoglobulin may supply some protection in susceptible persons (CDC, 2019). Herd immunity or high population coverage with MMR vaccine provides protection for those where immunization is contraindicated and is the most effective strategy to limit transmission and end measles outbreaks (CDC, 2019).
Occupational health nurses need to be vigilant about measles outbreaks and help raise immunization coverage rates to control future outbreaks. Occupational health nurses should provide evidence-based information on the safety and efficacy of vaccines for workers and their families plus ways to prevent transmission, specifically for international travelers and families with young children. Suspected measles must be reported to the local health department within 24 hours. Measles should be considered in any febrile rash illness with clinically compatible measles symptoms, especially if the person recently traveled internationally or was exposed to a person with febrile rash illness. Occupational health nurses can obtain resources and guidance from the CDC (https://www.cdc.gov/measles/index.html), the World Health Organization (2019) (https://www.who.int/immunization/diseases/measles/en/), and from individual state health department websites.
