With twice as many measles cases confirmed in the US this year compared to last, parents are increasingly opting to give their children the second dose of the MMR vaccine far earlier than the standard timeline, sometimes just weeks after the first.
The US Centers for Disease Control and Prevention (CDC) typically recommends the first MMR shot after a child turns one and the second between the ages of four and six. But the CDC also says giving the second shot as soon as four weeks after the first is an option, a practice recommended in countries including Germany, the United Kingdom and France.
"There's no reason to wait, measles is here now," said Elias Kass, a naturopathic physician and vaccine advocate in Seattle, Washington. He began recommending the combined MMRV shot at 15 months when cases began rising a few years ago, and said more parents are now taking the advice.
Margot Taylor, a mother of three in Chicago, said the vaccination schedule had to be accelerated because of increasing cases. Her eldest received the shots at ages one and four, but her second child was given the second dose at age two during a measles outbreak in Chicago. Her third received the first shot after her first birthday and the second just three months later.
Taylor worried the shots might not work as well if given so early, but evidence shows the vaccines still work well at earlier ages. The recommendation to give the second dose between four and six years is based more on logistics, ensuring children have both shots before kindergarten and cutting down on doctors’ visits, since other shots are typically given at those ages.
"There's absolutely no indication so far that any kid that has been vaccinated twice in any rhythm would have a higher risk of measles than someone who's been vaccinated according to the old rule," said Catherina Becker, a scientist in Germany. She argued the CDC should "absolutely" consider a stronger recommendation to give the second shot earlier.
Becker pointed to past outbreaks to illustrate the vaccine's effectiveness. In a 1998 outbreak in Alaska, only 17 people were sickened at a school where nearly all of some 2,186 students were vaccinated. She contrasted this with a 2010 outbreak at a Waldorf school in Germany, where nearly half of the 300 students were unvaccinated and 71 people were sickened.
"It shows you what the measles vaccine does for you – it protects you from getting this thing," Becker said.
Analysis
Why This Matters
- The shift away from the standard MMR schedule reflects growing urgency among parents to contain a preventable disease as outbreaks accelerate.
- The scientific evidence supporting early vaccination could prompt the CDC to formalise a recommendation that is currently only an option.
- How the US responds to this outbreak may determine whether its vaccination schedule aligns permanently with countries that moved to earlier dosing after their own outbreaks.
Background
The standard US schedule for the MMR vaccine (first dose at 12–15 months, second at 4–6 years) was established primarily for logistical convenience, ensuring children are protected before starting school. Countries like Germany, the UK and France already recommend the second dose within months of the first. The CDC allows the early schedule as an option, but does not strongly recommend it.
Key Perspectives
Parents like Margot Taylor: They accelerated their children's vaccination schedules because local outbreaks made the risk of waiting feel unacceptable, even if it meant learning the vaccine schedule themselves.
Scientists and physicians like Kass and Becker: They argue the evidence clearly shows early vaccination works well and the logistics-based standard schedule should be updated to reflect the current threat level.
What to Watch
- Whether the CDC issues a formal recommendation to move the second MMR dose significantly earlier.
- The trajectory of the current US measles outbreak, and whether it reaches the scale that prompted permanent policy changes in Europe.
- Whether the accelerated vaccination trend affects overall immunisation coverage rates.
Checked
12 claims in this story checked against 1 source: 12 supported.
Show each claim
- SupportedUS families are opting for earlier measles vaccinations amid an outbreak.World news | The Guardian: “Families in the US are opting for earlier measles vaccinations amid outbreak.”
- SupportedThe second dose can be given as soon as four weeks after the first, as some countries recommend.World news | The Guardian: “the second dose of the measles, mumps and rubella (MMR) vaccine, which can be given as soon as four weeks after the first. Giving the second shot soon after the first aligns with what some other countries, such as Germany, the United Kingdom and France, recommend”
- SupportedThe US has twice as many confirmed measles cases this year as last year.World news | The Guardian: “Measles cases are accelerating in the US, with twice as many confirmed cases as last year”
- SupportedKass said, “There's no reason to wait, measles is here now.”World news | The Guardian: ““There’s no reason to wait, measles is here now.””
- SupportedKass began recommending the MMRV shot at 15 months when measles cases began increasing a few years ago.World news | The Guardian: “Kass began recommending the MMRV shot, which combines the second MMR and chickenpox (varicella) into one, at 15 months of age when measles cases began increasing a few years ago.”
- SupportedThe CDC typically recommends the first MMR shot after age one and the second between ages four and six.World news | The Guardian: “The CDC typically recommends giving the first MMR shot after age one and the second between the ages of four and six.”
- SupportedTaylor's second child received the second dose at age two during a measles outbreak in Chicago.World news | The Guardian: “Taylor was surprised when the pediatrician recommended the second shot at age two. Chicago was battling a measles outbreak , so they went ahead with it.”
- SupportedBecker said there was no indication that children vaccinated twice on any schedule had a higher measles risk than those vaccinated according to the old rule.World news | The Guardian: ““There’s absolutely no indication so far that any kid that has been vaccinated twice in any rhythm would have a higher risk of measles than someone who’s been vaccinated according to the old rule,” said Catherina Becker, a scientist in Germany.”
- SupportedBecker said the CDC should “absolutely” consider a stronger recommendation for an earlier second dose.World news | The Guardian: “The CDC should “absolutely” consider a stronger recommendation to give the second shot earlier, Becker said.”
- SupportedIn a 1998 Alaska outbreak, 17 people were sickened at a school where nearly all of about 2,186 students had received measles shots.World news | The Guardian: “In a 1998 outbreak in Alaska, only 17 people were sickened at a school where nearly all students – some 2,186 in total – had received measles shots.”
- SupportedIn a 2010 outbreak at a Waldorf school in Germany, nearly half of 300 students were unvaccinated and 71 people were sickened.World news | The Guardian: “She compared it with a 2010 outbreak at a Waldorf school in Germany where nearly half of the 300 students were unvaccinated and 71 people were sickened.”
- SupportedBecker said, “It shows you what the measles vaccine does for you – it protects you from getting this thing.”World news | The Guardian: ““It shows you what the measles vaccine does for you – it protects you from getting this thing,” she said.”
