Cod liver oil and Vitamin A will not prevent measles cases in the U.S.

Take it from a doctor who has cared for patients with measles and sadly had to watch as some children died from the most infectious disease in the world.

Dr. Edward Janoff studied complications associated with measles back when he was an infectious disease fellow in the late 1980s. As part of his research, he helped care for hundreds of patients in the Philippines and Thailand who suffered from measles. Some experienced challenging and heartbreaking complications ranging from breathing difficulties to diarrhea to death.

Janoff’s guidance about measles is utterly clear:

“The best treatment for measles is not to get measles. And the best way not to get measles is to get the vaccine,” said Janoff.

He’s an infectious disease expert at UCHealth University of Colorado Hospital and the Rocky Mountain Regional VA Medical Center and a professor of medicine, infectious diseases, microbiology and immunology at the University of Colorado School of Medicine on the Anschutz Medical Campus.

Unlike Janoff, most doctors in the U.S. — even pediatricians and infectious disease experts — have never seen or cared for patients who are sick with measles. That’s because this dangerous, highly infectious disease was largely eradicated in the U.S. in about 2000. But measles now is making a dangerous comeback.

And as measles cases continue to rise, misinformation about ways to prevent and treat measles is spreading too. Doctors in Texas — where the largest measles outbreak is taking place this year — now are seeing some children who are suffering from Vitamin A toxicity. Too much Vitamin A in people who do not have Vitamin A deficiency, which is very uncommon in the U.S., can cause liver damage and other medical problems.

Despite possible dangers of Vitamin A poisoning, the use of cod liver oil, a common source of Vitamin A, has been rising in parts of the U.S. because some health officials and parents have falsely claimed that doses of cod liver oil and Vitamin A are good substitutes for the safe and highly effective measles vaccine. Those claims are not true, and they are dangerous because — in addition to causing potential Vitamin A poisoning — people who don’t get measles vaccines are highly vulnerable to getting sick with measles.

So, what is the truth about measles? What are evidence-based treatments for people who get measles? What’s it like to be sick with this dangerous disease? Is it ever appropriate to give children doses of Vitamin A or cod liver oil? How can doctors help people if they get measles? And what are some of the complications that people can experience if they get measles?

Janoff answered many of the top questions people are asking about measles now. (For additional information, read about the current measles outbreaks and why measles is so dangerous.)

Do cod liver oil and Vitamin A work as cures or treatments to prevent measles?

Cod liver oil and Vitamin A do not prevent measles, but the vaccine does.  Cod liver oil is a type of fish oil that contains a lot of Vitamin A and Vitamin D. In parts of the world where children are undernourished, small doses of Vitamin A can be beneficial to treat some children with measles. But neither cod liver oil nor Vitamin A are necessary for children in the U.S. since nearly all kids here are well nourished, Janoff said

“Cod liver oil is certainly not a miracle cure for measles,” he said.

Parents used to give children spoonfuls of cod liver oil or regularly fed them liver to try to boost Vitamin A and iron in attempts to stave off illnesses before groundbreaking vaccines prevented dangerous diseases like measles.

Janoff reiterated that the measles vaccine — which is called the MMR — is safe, highly effective and long-lasting. Getting the measles vaccine is the No. 1 way to stay safe from measles. The vaccine can give you a mild sore arm and, infrequently, can cause a short-lived fever and rash. But a real measles infection is much worse.

Why is the measles vaccine called the MMR?

The measles vaccine is called the MMR because people get vaccinated for the measles, mumps and rubella. Learn more about the recommended doses.

Why are the new measles outbreaks especially concerning?

The new measles outbreaks are worrisome because measles is so contagious. Hundreds of people are getting infected, and so far, two children in Texas have died from measles this year. If an unvaccinated person is exposed to someone with measles, the unvaccinated person is almost guaranteed to get it.

“If you are not vaccinated, you are at risk. If you are unvaccinated and you are exposed to measles, there’s more than 90% chance of getting infected,” Janoff said.

“Measles has a very high ‘attack rate,’ meaning it’s very successful at spreading from one unvaccinated person to another. It’s the most transmissible infectious disease in the world, more contagious than influenza, COVID-19, RSV and even Ebola. And everyone who gets measles gets sick,” Janoff said.

What did you witness when you saw patients with measles? What’s it like for children to be sick with this disease?

“When I worked in a very poor and crowded area in the Philippines, kids with measles were very sick. They had very high fevers. Their mouths were sore. They had a hard time eating and drinking. They had shortness of breath. Their eyes were red and itchy. The rash started by the hairline and the face, then it moves down to the chest and arms,” Janoff said.

Measles infections in the U.S. typically are not as severe as the illnesses Janoff saw in children abroad. Even so, the illness here often is much worse than a bad cold, he said.

“It can last a week to 10 days or as long as three weeks,” Janoff said.

Unlike chicken pox, where the rash can be very itchy and uncomfortable, the rash in measles is a sign of the illness, but the rash that comes with measles is not generally itchy or painful. Other symptoms can be much more uncomfortable and scarier in people who suffer severe cases of measles.

“With measles, you feel bad. You can be listless, very tired and short of breath with a lot of coughing. Some kids end up in the hospital because they can’t eat or drink easily. With the children I saw, dehydration was the biggest problem. They needed fluids and some needed oxygen.

“When kids died, they had respiratory failure or profound dehydration,” Janoff said. “Dealing with all of these phenomenally sick kids was really difficult and so sad, but not as difficult as it was for their parents and families.”

Are there any treatments or cures for measles?

There are no cures for measles. For people who are sick, doctors can provide fluids, oxygen and comfort measures to try to ease the symptoms. Vitamin A has been used with variable success in Africa to lower mortality with measles. Vitamin A may be used, but it has not been studied for treatment in the U.S.

For unvaccinated people who have been exposed to measles but do not yet have symptoms, doctors can give a dose of the measles vaccine within three-to-four days of exposure, and that vaccine dose can prevent the exposed person from getting sick, Janoff said.

Similarly, a therapy called “immunoglobulins” can stimulate a person’s body to fight the infection better and faster and prevent some people from getting sick soon after exposure. These immunoglobulins are made from antibodies, which are like arrows targeting the measles virus.

It’s much wiser to get affordable, accessible measles vaccines to prevent the illness in the first place, Janoff said.

How long is the incubation period for measles? How would I know if I was exposed?

The incubation period is long: from a week to three weeks. So, it’s possible for people to have been exposed to measles and not realize it.  Measles is most easily spread to others from four days before to four days after the onset of the rash.

What are some of the complications you witnessed when patients got severe cases of measles?

Many children with measles got secondary illnesses, Janoff said.

“Some had pneumonia, and many had diarrhea. In that setting, among undernourished poor children living in crowded conditions, many died. There was at least a 5% mortality rate. These were sick, malnourished, underserved kids living in slums in Manila in the Philippines,” Janoff said.

The children he saw in Thailand came from higher socioeconomic groups and were in better health before getting sick. Those children experienced fewer complications with measles, Janoff said.

Janoff and other researchers learned that, in addition to making people sick acutely, measles also undermines people’s immune systems, which can cause additional health problems. On top of measles, it’s also common to get secondary infections like ear infections, bronchitis, pneumonia and diarrhea.

“In Africa, diarrhea is a common complication and cause of death related to measles,” Janoff said. “Measles is a profound immunosuppressant. Once you have measles, you are more likely to get other bacterial and viral infections.”

Influenza can cause similar complications. It harms the cells that line the lungs and makes it easier for bacteria to infect the lungs.

“If you get influenza, a week or two later, you can get bacterial pneumonia,” Janoff said.

Measles can also cause progressive neurological deficits.

“Some patients get brain inflammation,” Janoff said.

Along with short-term side effects, can measles also cause long-term side effects?

Measles can have long-term side effects. Along with an array of side effects at the time of infection — from pneumonia to diarrhea to brain inflammation, which is also called encephalitis — measles can also trigger a rare, terrible illness five to 20 years after the original infection.

A small percentage of people can get a fatal condition called SSPE, which stands for Subacute Sclerosing Panencephalitis.

“It’s a long-term complication that affects about 1 in 5,000 people who get measles. It causes confusion and seizures. It’s progressive. There are no treatments, and you end up dying,” Janoff said.

For infectious disease experts who have witnessed the dangers of measles, how tough is it to see spikes in measles outbreaks?

“It saddens me,” Janoff said. “It’s very clear that measles is a very bad infection. And any side effects from the vaccine are very minor compared to the effects you get from the disease.”

He said most people in the U.S. who are skipping vaccines have never seen the scary impacts of vaccine preventable diseases like measles, polio and diphtheria, which used to be common and routinely made millions of people sick every year.

“Most people don’t know how bad these diseases are. Instead, they might hear about minor side effects with a vaccine,” he said.

In Janoff’s own family, a disease that vaccines now prevent took a terrible toll.

“My father had 11 kids in his family, and two of them died of diphtheria,” Janoff said.

When the vaccines for diphtheria, polio and measles came out, most people were overjoyed and relieved. Parents were thrilled when their children could receive vaccines in schools.

“We went from every child in the country getting measles to fewer than 200 cases a year. That’s pretty dramatic and an amazing success story,” Janoff said.

Now, misinformation is reversing years of progress, Janoff said.

He cited declining child mortality rates as a public health victory that could erode over time.

Global child mortality rates have declined dramatically in recent decades, dropping from nearly 13 million deaths a year in children under age 5 in 1990 to about 5 million deaths in young children in 2022, according to the World Health Organization.

And since the measles vaccine was developed in 1963, it has literally been a lifesaver.

“The measles vaccine has prevented about 25 million deaths. It’s been an effective and safe vaccine. Some people don’t get it because they don’t have access to it,” Janoff said.

But people who do have access to the measles vaccine should definitely get it, he said.

“Measles selects vulnerable people. It can be mild or terrible or fatal. It’s a very serious worldwide disease.”

Tell us more about the eradication of measles in the U.S.

Prior to 1963, measles was extremely common in the U.S. and around the world.

“It was a serious worldwide disease,” Janoff said. “Every child in America got it.”

According to experts at the U.S. Centers for Disease Control and Prevention (CDC):

• About three to four million people were infected with measles in the U.S. every year.
• Among those who got measles each year prior to widespread use of the measles vaccine:
  • 400 to 500 children died.
  • 48,000 were hospitalized.
  • 1,000 suffered encephalitis (swelling of the brain).

Concerted efforts to require at least 95% of children to get vaccinated for measles by the time they started school helped sharply reduce the number of measles cases in the U.S. By 2000, health experts declared that measles had been eradicated in the U.S., meaning there were no longer any endemic cases in the country.

After the eradication of measles in the U.S., a handful of cases of measles cropped up each year, but all of those could be traced to people who were exposed to measles by those from outside the U.S. and later got sick. Measles outbreaks in the U.S. began increasing before the COVID-19 pandemic due to increased misinformation and accompanying vaccine hesitancy. Vaccine refusal increased during the pandemic. Today, homegrown cases are spreading in Texas, New Mexico, Oklahoma and elsewhere.

Who should get a measles vaccine or a booster shot now?

Here is some helpful guidance based on the year in which you were born, according to the CDC and the Wall Street Journal:

• Anyone who was born before 1957 is presumed to have been exposed to the measles as a child.
• Once you get the measles, you have lifelong immunity.
• People who were born between 1957 and 1963 — when the measles vaccine came out are likely to be protected. Many people born during these years are likely to have been infected as children. Some might have been vaccinated later. If you can track down your vaccination records, you can check. Otherwise, you can consult with your doctor who can do a test to measure immunoglobulin G or IgG to see if you have immunities to measles in your blood. Or you can get a booster shot.
• People born between 1963 and 1967 may have received a less effective version of the measles vaccine and might wish to get a booster shot of the current vaccine.
• People born between 1967 and 1989 likely got one dose and generally don’t need a second dose.
• People born after 1989, who were fully vaccinated, should have received two doses and should be well protected.
• If you were never vaccinated as a child, work with your doctor to get vaccinated now.
• If you don’t know your vaccine history, it’s wise to check with your doctor on the best plan to stay protected.

Measles is extremely contagious. How did you stay safe while caring for patients who were sick with the disease?

Janoff is a rare person who is 100% sure that he had measles. That’s because his parents shot a home movie of him on his 4th birthday in May of 1958. And instead of having a party or playing outside, Janoff is hanging out in a red bathrobe, holding a sign that says, “Happy 4th Birthday! Eddie has measles.”

Janoff doesn’t recall what it was like to have measles, but since he knew he had had the disease — and therefore had lifelong immunity — he was able to study the disease and care for patients with measles without worrying about getting the disease again himself.

What about pregnant women and newborns? Can they get vaccines to prevent measles?

People who hope to get pregnant should get vaccinated before they get pregnant. Pregnant women and newborns who are less than six months old cannot get the measles vaccines. That’s also true for some people who are immunocompromised, like people with leukemia or those with advanced HIV.

If parents are struggling with decisions about vaccines, what would you tell them?

Janoff’s advice is quite simple: protect your children and protect other people’s children. Getting measles is worse than getting the vaccine. If enough people get vaccines to prevent illnesses like measles, entire communities will be healthier and safer. We are lucky in the U.S. that vaccines are safe, effective, affordable and accessible.

“Getting measles is not a good thing,” Janoff said. “It’s a serious, aggressive virus for people of any age. Get vaccinated.”