Measles cases are on the rise in the US

Measles is a highly contagious respiratory infection, and the virus can be spread through the air, infectious droplets, or on surfaces.

"If a person has not been exposed or vaccinated, then they generally get infected if they are exposed 90% of the time," said Katherine Baumgarten, medical director for infection control and prevention at Ochsner Health.

Some common symptoms of measles include high fever, coughing, runny nose, and red watery eyes. Measles patients may also develop small white spots inside their mouths, as well as a blotchy rash all over their body. According to CDC, symptoms typically appear between seven and 14 days after a person has been exposed to the virus.

Measles can also lead to severe complications, such as blindness or long-term vision problems, as well as death. Around one to three out of every 1,000 children who are infected with measles will die from respiratory and neurological complications.

In 1963, the first measles vaccine became available, and by 2000, the virus was declared to be eradicated in the United States. However, there have been sporadic outbreaks since then, largely linked to overseas travel to countries where measles is spreading. The largest outbreak since the early 1990s occurred in 2019 with 1,274 confirmed cases across 31 states.

So far this year, 35 measles cases have been reported across 15 states. The two biggest outbreaks have been in Florida, which recently confirmed its 10th case, and Pennsylvania, which has had nine cases between December and January.

Measles cases have also increased globally, with a report from the World Health Organization and CDC finding an 18% increase in cases from 2021 to 2022. "Measles is coming back, and with that there's more chance of importation into the United States," said Walter Orenstein, from Emory University School of Medicine.

Vaccination is key to protecting yourself from measles

Currently, CDC recommends people get two doses of the measles vaccine, with the first dose at 12 to 15 months and the second dose between the ages of 4 and 6. One dose is 93% effective against measles while two doses is 97% effective.

According to health experts, lagging vaccination rates, particularly during the pandemic, are likely behind the current measles outbreak in the United States. For almost 10 years, the measles vaccination rate among U.S. kindergarteners was 95%, but declined to 93% in the 2022–2023 school year.

"In order to prevent any pandemic or epidemic for measles, you really have to have an immunization rate of 95%," said Samir Midani, the division chief of pediatric infectious diseases and immunology at Nemours Children's Health in Jacksonville, Florida.

"The ones that are getting measles are those that are simply not vaccinated, for whatever reason, whether it's mistrust of the public healthcare system, [or] maybe they're having eroding confidence in their healthcare providers," said Steven Schweon, a member of the Emerging Infectious Diseases task force for the Association for Professionals in Infection Control and Epidemiology. "They may believe misinformation that's out there, as opposed to credible information."

To reduce the risk of infection, Schweon recommends healthcare providers ask if patients have been vaccinated, and if they haven't, vaccinate them as soon as possible. "Healthcare providers should be asking [patients] about their vaccine history, if they are up to speed with their vaccines," he said, "and if their patients aren't sure, depending on the vaccine and why, it's a great opportunity to vaccinate them right there in the office."

Orenstein also noted that healthcare providers should prioritize building trust with their patients to address any potential concerns and overcome vaccine hesitancy.

"It's important to try and explain that getting the measles vaccine is your protection -- and protects them from diseases -- that will prevent hospitalizations, pneumonia, ear infections and even encephalitis or brain damage," Orenstein said. "So we need to get that message across, and we need to find the right messengers." (Timsit/Sun, Washington Post, 2/29; Bendix, NBC News, 2/28; Park, TIME, 2/28)

In the wake of the COVID-19 pandemic, jurisdictions are re-evaluating the role and strength of their public health institutions. Advisory Board's Isis Monteiro examines Brazil's public health system and how its track record of running successful immunization campaigns have promoted "cultural faith" in vaccines.