Six years ago, two communities in New York – one in Brooklyn and one in Rockland County – were facing the worst measles outbreaks the United States had seen in decades. Measles had been declared eliminated from the country in 2000, but 2019 brought the nation the closest it has been to losing that status.
Now, measles outbreaks are growing in West Texas and New Mexico. Testing sites and vaccine clinics have opened in outbreak areas and the US Centers for Disease Control and Prevention arrived in Texas last week to support the response. Still, local health officials say spread could continue for months.
Back in 2019, swift, sustained efforts to curb the measles virus brought the country back from the brink. The response centered on the unique needs of communities that were most at risk, powered by hands-on public health work that was supported by formal policy changes. Experts say the way the outbreak played out in New York underscores the importance of an all-hands-on-deck approach to stop the spread in other outbreaks.
The most important tool
The outbreaks in New York, which started at the end of 2018 and persisted through most of 2019, were concentrated in Orthodox Jewish communities that had been targeted with anti-vaccine disinformation for years.
Public health experts who were part of the on-the-ground response say that building trust within the community was perhaps the most important part of their work because it created opportunities to better utilize the most important tool available: vaccines.
“Vaccination is the most important way to prevent the devastating disease that measles can be,” said Dr. Neil Vora, executive director of Preventing Pandemics at the Source, a coalition of organizations focused on reducing risk from novel viruses. He was heavily involved in responding to the measles outbreak in 2018 and 2019 as a US Centers for Disease Control and Prevention employee working out of the New York City health department at the time.
Two doses of the measles vaccine are 97% effective at preventing disease, and immunity from the shot is long-lasting. Because measles is so contagious, federal health agencies say that a 95% vaccination rate is needed to prevent outbreaks.
“We were up against quite a bit of resistance in terms of getting people vaccinated as quickly as we would have liked,” said Dr. Oxiris Barbot, president and chief executive officer of the United Hospital Fund, a nonprofit organization focused on improving health care in New York City. She was the city’s health commissioner during the measles outbreak between 2018 and 2019.
“I think it took more time than we would have anticipated, but that just really spoke to the degree of how hardened the disinformation had become in that community and what we were fighting against,” she said. “That’s why it’s so important to rely on trusted messengers to make it easy for people to get vaccinated and to have leaders that lead with the importance of vaccination. I can’t really overstate the importance of that.”
New York City also benefited from a strong vaccine registry that helped public health workers identify the people who were most at risk and focus their efforts, Vora said.
“One of my big concerns is that other jurisdictions in the country are not as well-resourced as we are in New York City, so when they face outbreaks, they’re going to have even more trouble than we had in getting those outbreaks under control,” he said.
The work required a highly individualized approach, with workers knocking directly on doors and making time to answer questions about vaccination one-on-one, Barbot said.
“There were certainly many people where we went to their homes to be vaccinated. There were instances where we went in essentially undercover, so that their neighbors wouldn’t know that they were getting vaccinated,” she said.
Vaccine campaigns avert larger crisis
The measles vaccine can build immunity quickly – it takes just a few weeks to reach its full effectiveness – and the efforts in New York paid off.
A retrospective modeling study found that vaccination campaigns during the measles outbreak in New York City averted an even larger spike in cases. The outbreak could have been at least 10 times worse than it was, with up to 8,100 people infected instead of the 649 cases reported by the city, according to the report by Dr. Wan Yang, an assistant professor of epidemiology at Columbia University’s Mailman School of Public Health.
But once an outbreak starts, experts say, increasing vaccination rates isn’t the only factor to consider. Findings from Yang’s study also suggest that “measles parties” – where children are brought together to intentionally spread the disease with the goal of creating immunity – accelerated spread.
Infants are typically most susceptible to a measles infection because they are typically not eligible to be vaccinated until age 1. At the beginning of the outbreak in September 2018, Yang’s work suggests, more than half of infants in the community were susceptible, along with about a quarter of young children between the ages of 1 and 4 who were the second most susceptible.
The initial vaccination campaigns lowered susceptibility rates by about 10 percentage points by the end of December, and the efforts “appeared to effectively contain the outbreak at the time,” according to Yang’s study; estimates suggest that each new case was linked to just one additional case at the end of the year, low enough to potentially avoid an epidemic.
But the chains of transmission grew quickly in the early months of 2019, faster than changes in susceptibility from vaccination rates could explain, suggesting that close contact rates were had increased, especially among young children.
Measles outbreaks are “dynamic,” Yang said. “It’s not just susceptibility that is determining how many new cases you are going to get. It also has to do with how people are interacting with each other.”
Data shows that were surges in the numbers of vaccines administered at certain key points: around the start of the school year, for example, and when the city issued a mandate that children living in certain ZIP codes be vaccinated to attend school or day care.
This intensive work required a persistent, all-hands-on-deck approach, Barbot said. The only situation that required a comparable amount of dedicated staff and time was the Covid-19 response.
Forging crucial relationships
In April 2019, about five months after the initial measles cases were reported in New York, officials in both New York City and Rockland County declared a state of emergency due to measles – a move that was also quite extraordinary before the Covid-19 pandemic.
“The emergency declaration gave us the resources that we needed on an ongoing basis to make sure that lack of resources wasn’t a reason why we couldn’t bring the outbreak to an end,” Barbot said.
But official mandates and emergency declarations supported the more informal work that had already been happening on the ground, experts say. Strong relationships that were forged between public health workers and trusted community leaders helped with broader communication strategies to dispel disinformation about the vaccines, as well as misconceptions about measles being a benign disease.
Dr. Blima Marcus, a nurse practitioner at the Bellevue Hospital Center, used her expertise as a health care provider and a member of the Orthodox Jewish community to forge inroads with a culturally sensitive approach.
“I think that the only thing that really can help is when your own community can find the resources to mobilize and start knocking on doors, literally and figuratively, to reach people where they’re at and start slowly changing the narrative,” she said. “The notion that there’s no one to ask and there are no answers to these deep vaccine questions – that’s false, and [that notion] is part of what we were hoping to change.”
Marcus helped develop a pamphlet with information about the measles-mumps-rubella (MMR) vaccine that was distributed to about 10,000 homes, a plan specifically designed to address anti-vaccination messaging that had been infiltrating the community and to reach individuals who might be less inclined to find information through digital media.
She and other community members knew that they had to be nimble in responding to a rapidly changing situation – strategically addressing misinformation as it arose and focusing on particular parts of the community most in need – and they were often moving faster than formal government systems would allow.
“Even if you have emergency funding, it’s not as emergent as we actually need,” Marcus said.
When the outbreaks were declared over, Rockland County had 312 confirmed cases and New York City had 649. No deaths from measles were reported during the outbreaks.
The current outbreaks haven’t reached that size yet. This year, nearly 230 measles cases have been identified in outbreaks in West Texas and a nearby New Mexico county, with the first case confirmed about a month and a half ago and two deaths of people with measles.
Much of the current outbreak is concentrated among a tight-knit Mennonite community, which faces some similar vulnerabilities as the Orthodox Jewish communities in New York did.
“What I felt was very effective in making connections, in forging inroads and, ultimately, in many places, increasing immunization rates is having that culturally competent teamwork because people are averse to being told what to do by others who they feel don’t understand them or their belief systems,” Marcus said.