(BPT) - Measles outbreaks continue to be reported throughout the United States. The increased risk of outbreaks can be largely attributed to the drop in pediatric vaccination rates from 2020 to 2022. Vaccination rates steadily declined over the course of the COVID­-19 pandemic, placing certain populations at a greater risk for vaccine-preventable infectious diseases and outbreaks.

'Vaccines have helped to protect millions of people worldwide against many serious diseases.' shared pediatric vaccine expert Michelle Goveia, M.D., MPH, and Global Medical and Scientific Affairs Executive Director at Merck. 'But vaccines only work when people get vaccinated.' Though measles was declared eliminated in the United States in 2000, cases of measles have been on the rise in recent years. In fact, 2019 saw the highest number of reported cases since 1992.

When the COVID­-19 pandemic caused initial stay-at-home orders in March-May 2020, families were hesitant to go to the doctor's office for fear of being exposed to coronavirus, thus, pediatric vaccination rates dropped substantially compared with the same period in 2018 and 2019. During this time, the routine vaccination programs in the United States were not able to work as well as they should have, which meant that many children did not get vaccinated or did not receive all the vaccines they needed.

Among the vaccination rates that saw a decline since the start of the pandemic is the vaccine against measles, mumps, and rubella. Dr. Goveia agreed and noted 'the decline in measles vaccination rates has resulted in outbreaks due to the extremely infectious nature of the virus. Outbreaks are happening as travel and social interactions continue to increase by children attending daycare and schools, interacting on playgrounds, and gathering in large groups.' From January to March 2024, 58 cases of measles were confirmed in the U.S. across seven outbreaks. Among these cases reported, 93% were linked to international travel.

Measles, also known as rubeola, is a serious illness. Measles spreads through the air when an infected person coughs or sneezes. It is so contagious that if one person has it, 9 out of 10 people around him or her will also become infected if they are not immune. Symptoms of measles including high fever, cough, and rash usually begin 10-14 days after exposure to the virus. It can cause pneumonia and in rare cases encephalitis (infection and swelling of the brain). This could lead to seizures, hearing loss, intellectual disability, and even death. Measles is often the first disease to resurge when pediatric vaccination rates drop because it is the most contagious of all vaccine-preventable diseases. This places communities at heightened risk for measles outbreaks.

M-M-R^®_II (measles, mumps, and rubella virus vaccine live) is a vaccine that is given as a shot. This vaccine is usually given to people one year old or older. It is meant to help prevent measles (rubeola), mumps, and rubella (German measles) and contains weakened forms of measles virus, mumps virus, and rubella virus. The vaccine works by helping the immune system prevent measles, mumps, or rubella infections. However, it may not provide complete protection for everyone who receives it. It is important to note that the vaccine does not treat measles, mumps, or rubella once someone has already contracted these diseases.

People should not get M-M-R^® _II if they are allergic to any of its ingredients, including gelatin; have a weakened immune system (which includes taking high doses of steroids by mouth or in a shot); have a fever; have active tuberculosis that is not treated; or are pregnant or plan to get pregnant within the next month.

While routine vaccinations help to protect millions of children from vaccine-preventable infectious diseases, immunocompromised people may not be able to receive certain vaccinations, like the measles vaccine, putting them at risk for severe disease.

Jen, a mother of two in Seattle, has experienced this firsthand. Her daughter, Zoe, received a heart transplant at 5 weeks old, precluding her from receiving her measles, mumps, and rubella vaccination due to the immunosuppressant regimen required to prevent rejection of the donor heart. When a measles outbreak began in Seattle in 2019, Zoe was at high risk for infection. As infections increased in certain areas of the city, Jen needed to remain in close contact with Zoe's doctors to determine the safest course of action for her daughter.

When diseases circulate in the community, unvaccinated people are at greater risk of getting those diseases.

That includes people like Zoe, who can't get vaccinated against measles. 'When these measles outbreaks happen, it's frustrating that we have to consider pulling Zoe from simple activities, like going to school," shared Jen. "If immunocompromised individuals like Zoe are exposed to a disease like measles, it can be really serious.'

'A five-minute exposure to measles can put unvaccinated and vulnerable people at risk,' shared Rabia Agha, M.D., Division Director, Pediatric Infectious Disease at the Maimonides Children's Hospital in Brooklyn, New York. Dr. Agha and her team helped to manage a Brooklyn-based measles outbreak that took place in 2019. 'Many people don't realize how contagious measles really is. The virus can stay in the air for up to two hours after an infected person has left the room.'

The perceived risks given the lower prevalence of vaccine-preventable infectious diseases in the United States today can lead to questions about the need for vaccinations. However, exposure to a virus can lead to an outbreak if introduced to a susceptible community. 'The decisions we make as individuals can potentially put others at risk and impact the health of the community we live in,' said Dr. Agha. 'Keeping up with routinely recommended vaccinations is a good place to start.'

If your child gets M-M-R^® _II (measles, mumps, and rubella virus vaccine live) when he or she is one year or older, a second dose is recommended. Often, the second dose is given right before the child goes to elementary school (4 to 6 years of age) but may be given earlier as long as the second dose is at least one month after the first dose.

It is important to speak with your child's health care provider and schedule any catch-up vaccinations that may have been missed due to COVID-19.

Talk to your child's doctor today to make sure your child is up to date with all their recommended vaccines.

Important Safety Information for M-M-R^®_II (Measles, Mumps, and Rubella Virus Vaccine Live)

Measles, mumps, and rubella virus vaccine live should not be given if you or your child are allergic to any of its ingredients, including gelatin; have a weakened immune system (which includes taking high doses of steroids by mouth or in a shot); have a fever; have active tuberculosis that is not treated; or are pregnant or plan to get pregnant within the next month.

Before getting the vaccine, tell your health care provider if you or your child: have or have had any medical problems; have a history of seizures or someone in your family has a history of seizures; have received blood or plasma transfusions or human serum globulin; take any medicines (this includes nonprescription medicines and dietary supplements); have any allergies; had an allergic reaction to any other vaccine; have or have had a low blood platelet count; or are allergic to eggs.

The most common side effect of vaccination with the measles, mumps, and rubella virus vaccine live is pain at the site of the shot for a short time. Other side effects may include fever or rash. Other side effects may also occur.

Your doctor has a more complete list of side effects. Contact your doctor or health care provider if you or your child have any new or unusual symptoms after receiving the vaccine. Report exposure to the measles, mumps, and rubella virus vaccine live during pregnancy or during the month before getting pregnant.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-­800-FDA-­1088.

Please read the accompanying Patient Information for M-M-R^®_II and discuss it with your doctor. The Prescribing Information also is available.

Patient Product Information: https://www.merck.com/product/usa/pi_circulars/m/mmr_ii/mmr_ii_ppi.pdf.

Prescribing Information: https://www.merck.com/product/usa/pi_circulars/m/mmr_ii/mmr_ii_pi.pdf

This information is provided by Merck.

Copyright © 2024 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved. US­-MMR-­00422 04/24