Measles outbreak in Illinois highlights the importance of vaccination

In a recent study published in Morbidity and Mortality Weekly Report (MMWR), Researchers in the US state of Illinois reported five measles cases among unvaccinated children who lived in the same building but did not interact with each other.

Notes from the field: Measles outbreak — Cook County, Illinois, October-November 2023. Image credit: adriaticfoto / Shutterstock

background

Although measles is an infectious disease that is preventable through vaccination, it poses serious health risks. In the United States, two doses of measles, mumps, rubella (MMR) vaccine are recommended for children, usually given between 12 and 15 months of age and between 4 and 6 years of age. They will be re-vaccinated in between. This study describes an alarming case of a measles outbreak among her five unvaccinated children from her two families who lived in the same building and had no interaction with each other. Masu.

Case

On October 5, 2023, Patient A, a 2-year-old immigrant from Yemen, was admitted to the emergency department (ED) of Hospital A after testing negative for influenza and coronavirus disease 2019 (novel coronavirus disease 2019). ) was diagnosed with an unspecified viral disease. 19), respiratory syncytial virus, etc. Patient A had not received her MMR vaccine and had symptoms of fever, cough, and coryza. On October 8, Patient A visited the emergency department of Hospital B due to worsening respiratory symptoms and tested positive for rhinovirus/enterovirus. Patient A was then re-admitted to Hospital A due to respiratory distress.

Specifically, patient A developed a maculopapular rash during hospitalization the next day. On October 10, the family revealed that they had been in contact with someone who had been diagnosed with measles before entering the United States. Measles was confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR) and the patient was discharged.

investigation

Between October 5th and 11th, the child was potentially exposed to 247 healthcare workers and 177 patients and relatives. These included 13 infants under 1 year of age, 5 immunocompromised children, and 1 of her unvaccinated children over 1 year of age. Two of these children received the MMR vaccine within 3 days of exposure, and 13 received immunoglobulin as a prophylactic measure.

Domestic contacts of patient A included two siblings who had not received the MMR vaccine and were found to be susceptible to measles by serology. The siblings were patient B, 4 years old, and patient C, 9 years old. While in quarantine, the brothers contracted measles and developed various symptoms. Patient B required her ED visit for supportive care, but neither child was admitted. A warning was issued to all occupants of the building on October 17th.

On October 30th, Patient D, another 2-year-old child, came to the emergency department complaining of symptoms and lived on a different floor of the same building as Patient A. The child was not vaccinated with the MMR vaccine because his parents were concerned about it and opposed it. Vaccine side effects. Measles was confirmed by RT-PCR.

Interestingly, despite living in the same building, the families of both patients had different cultural backgrounds and languages. Both families denied any contact. Their apartment units did not share ventilation, but did share laundry facilities and a building entrance.

On October 31, Patient D's unvaccinated 1-year-old sibling, Patient E, was evaluated for an isolated coryza. The child attended a day care facility on October 30th despite having symptoms, and the case was confirmed to be measles through an RT-PCR test. Susceptible individuals were given post-exposure prophylaxis, with one child receiving immunoglobulin and the other receiving an early second dose of MMR vaccine. Patient E did not have a fever until November 6, but developed a rash on November 9, 9 days after the child care facility was notified of the positive test result.

Testing for measles is usually done when prodromal symptoms such as cough, fever, coryza, and conjunctivitis occur, but the isolated coryza experienced by Patient E may not have been measles-related. . Because measles testing is rarely performed before a fever develops, it was difficult to accurately determine the duration of infection in this patient. Patient E did not require hospitalization.

discussion

In this outbreak, five children were infected with measles. They were not vaccinated despite being eligible for the MMR vaccine due to cultural barriers, limited access to health care, and refusal of the vaccine. Although outbreaks between close-knit communities have been observed before, the current family was not part of such a network. Public health responses typically include tailored approaches, such as culturally appropriate educational materials and translation services. However, these efforts are costly and time-consuming. This outbreak highlights the highly contagious nature of measles, even among children who have no contact with each other.

conclusion

In conclusion, this study highlights the need for all children and susceptible persons to receive two doses of the MMR vaccine at appropriate intervals. Clinicians should suspect measles in patients with febrile rash illness and ensure vaccination to prevent future outbreaks.