At CHOP, our doctors have been responding to a steady stream of questions from concerned parents who want to better understand the latest measles outbreak in Texas and New Mexico, how they can keep their kids protected and what the truth is in the debate about vaccinations.
The number one thing for parents to know: The most important thing you can do to protect your family is make sure all children and adults in your household are up to date on their recommended vaccinations and that children get their measles, mumps and rubella (MMR) vaccine at the recommended age (first dose at 12 months and a second dose at 4 to 6 years of age). The vaccine for measles is extremely effective — about 95 to 99 of 100 people who have been vaccinated will be protected — and it is our best defense against this highly contagious, serious disease.
What is happening now?
Since late January, public health officials in Texas have identified 146 cases of measles in Northwest Texas, starting in Gaines county. One child has died. There are also 9 additional measles cases in adjacent New Mexico Lea county. Additional cases of measles have been reported in California, Alaska, Kentucky, and New Jersey (Bergen county) as well as a recent case in a returned traveler in Pennsylvania (Montgomery county). (Data as of February 28, 2025.)
What is measles?
Measles is a highly contagious, viral respiratory illness. It is one of the most infectious viruses that we see. To put it in context – when a person has norovirus (the infamous highly contagious stomach virus), they typically infect approximately 2 other people. When a person has measles, they infect approximately 12-18 other people.
Measles can cause:
- Cold-like symptoms, such as runny nose/congestion, cough or fever
- Red, watery eyes, also known as pink eye (conjunctivitis)
- Small white spots, known as Koplik’s spots, inside the mouth that develop about two to four days before rash onset but quickly disappear after rash appears
- A distinct blotchy, red rash that appears two to four days after the first symptoms (though this can vary) and starts on the face and neck and spreads downward
Why is measles so serious?
Some people with measles may experience complications, such as pneumonia, swelling of the brain, seizures and — in extreme cases — death.
- 1 in 20 children with measles get pneumonia
- 1 in 5 children with measles are sick enough to need hospitalization
- Approximately 1 to 3 in 1,000 children who get measles die from their infection
Once a common childhood illness that affected mostly preschool- and school-aged children, measles has been relatively nonexistent in the U.S. in recent years. This low incidence of measles is the result of widespread vaccination. Measles vaccination is highly effective in preventing infection. Unfortunately, we are seeing rising cases of measles in the last few years because of decreases in vaccination rates.
There is no cure for measles. There are no antibiotics or antiviral medications that treat measles.
How can I protect my family during measles outbreaks?
The most important thing you can do is make sure all children and adults in your household are up to date on their recommended vaccinations — all of them.
Because measles is highly contagious, it’s also important for parents to take precautions with children who are either too young to be vaccinated, have weak immune systems, or who cannot get the vaccine for medical reasons.
For non-immune (including infants under 1 year) or immunocompromised individuals, it is strongly recommended to avoid travel to areas with active community transmission. If you live in or cannot reschedule your visit to an area where multiple cases of measles have recently been reported, it’s important to limit your susceptible child’s exposure to other people and public areas where infected people might have visited.
During periods when outbreaks are not occurring, it’s safe to run normal errands with your baby — just be sure to practice the usual precautions to keep your child from getting sick: Don’t allow strangers to hold or play with your baby; keep your child away from anyone with a fever, cough, or other respiratory symptoms; and make sure you and your family wash your hands regularly.
What should you do if you think you have been exposed to or infected with measles?
Due to the highly contagious nature of measles, please contact your healthcare provider before you go to a doctor’s office or care center if you believe you have been exposed to or may be infected with measles. They will give advice on precautions to take before entering any facility to avoid potentially exposing others.
Can my child get vaccinated before they’re 12 months old?
A mother who has been immunized with the measles, mumps and rubella (MMR) vaccine or previously had measles passes on antibodies to her unborn baby. These antibodies provide protection for up to six months, and possibly longer. Babies are not routinely recommended to get the vaccine before 1 year of age because the antibodies they’re getting from their mom might interfere with how well the vaccine works before that time.
The current outbreak has not changed this recommendation. Your providers will continue to monitor guidance for vaccination recommendations if measles activity continues to rise regarding age of vaccination.
The MMR vaccine is still recommended for children 6 months and older at least two weeks prior to any international travel.
If the vaccine is so effective, and 90 percent of U.S. population has been vaccinated, why is measles spreading?
The MMR vaccine is extremely effective — about 95 to 99 of 100 people who have been vaccinated will be protected. However, measles is extremely contagious. Any place crowds of people are gathered, a person with measles could expose many others.
Unfortunately, some of those exposed may not be immune because:
- They are too young to be immunized.
- They have a medical reason why they cannot be immunized.
- They have a weakened immune system and may not be protected by the vaccine.
- Their parent/guardian chose not to get the measles vaccine for them as a child.
- They may never have received the vaccination by choice.
- They are one of the rare few for whom the vaccine didn’t work.
For these reasons, measles can quickly spread through a population when unvaccinated or susceptible persons are exposed. This is why staying up to date on vaccinations is so important: Vaccines break the chain of transmission.
Is the measles vaccine safe?
Yes. Like any medicine, vaccines do have side effects, yet scientific studies have long confirmed the safety of the MMR vaccine. Concerns about vaccines causing autism have been addressed by dozens of scientific studies and have shown that children who receive vaccines are at no greater risk for developing autism than those who do not receive vaccines.
On the flip side, children who do not receive vaccines are at increased risk of suffering from a vaccine-preventable disease.
Get more information about measles and the MMR vaccine from CHOP’s Vaccine Education Center.
- Watch "Doctors Talk: Measles"
- A Look at the Measles, Mumps and Rubella (MMR) Vaccine
- Measles: What You Should Know (Q&A) in English | Spanish | Japanese
- News & Views: What Should I know About the New MMR Vaccine, PRIORIX?
At CHOP, our doctors have been responding to a steady stream of questions from concerned parents who want to better understand the latest measles outbreak in Texas and New Mexico, how they can keep their kids protected and what the truth is in the debate about vaccinations.
The number one thing for parents to know: The most important thing you can do to protect your family is make sure all children and adults in your household are up to date on their recommended vaccinations and that children get their measles, mumps and rubella (MMR) vaccine at the recommended age (first dose at 12 months and a second dose at 4 to 6 years of age). The vaccine for measles is extremely effective — about 95 to 99 of 100 people who have been vaccinated will be protected — and it is our best defense against this highly contagious, serious disease.
What is happening now?
Since late January, public health officials in Texas have identified 146 cases of measles in Northwest Texas, starting in Gaines county. One child has died. There are also 9 additional measles cases in adjacent New Mexico Lea county. Additional cases of measles have been reported in California, Alaska, Kentucky, and New Jersey (Bergen county) as well as a recent case in a returned traveler in Pennsylvania (Montgomery county). (Data as of February 28, 2025.)
What is measles?
Measles is a highly contagious, viral respiratory illness. It is one of the most infectious viruses that we see. To put it in context – when a person has norovirus (the infamous highly contagious stomach virus), they typically infect approximately 2 other people. When a person has measles, they infect approximately 12-18 other people.
Measles can cause:
- Cold-like symptoms, such as runny nose/congestion, cough or fever
- Red, watery eyes, also known as pink eye (conjunctivitis)
- Small white spots, known as Koplik’s spots, inside the mouth that develop about two to four days before rash onset but quickly disappear after rash appears
- A distinct blotchy, red rash that appears two to four days after the first symptoms (though this can vary) and starts on the face and neck and spreads downward
Why is measles so serious?
Some people with measles may experience complications, such as pneumonia, swelling of the brain, seizures and — in extreme cases — death.
- 1 in 20 children with measles get pneumonia
- 1 in 5 children with measles are sick enough to need hospitalization
- Approximately 1 to 3 in 1,000 children who get measles die from their infection
Once a common childhood illness that affected mostly preschool- and school-aged children, measles has been relatively nonexistent in the U.S. in recent years. This low incidence of measles is the result of widespread vaccination. Measles vaccination is highly effective in preventing infection. Unfortunately, we are seeing rising cases of measles in the last few years because of decreases in vaccination rates.
There is no cure for measles. There are no antibiotics or antiviral medications that treat measles.
How can I protect my family during measles outbreaks?
The most important thing you can do is make sure all children and adults in your household are up to date on their recommended vaccinations — all of them.
Because measles is highly contagious, it’s also important for parents to take precautions with children who are either too young to be vaccinated, have weak immune systems, or who cannot get the vaccine for medical reasons.
For non-immune (including infants under 1 year) or immunocompromised individuals, it is strongly recommended to avoid travel to areas with active community transmission. If you live in or cannot reschedule your visit to an area where multiple cases of measles have recently been reported, it’s important to limit your susceptible child’s exposure to other people and public areas where infected people might have visited.
During periods when outbreaks are not occurring, it’s safe to run normal errands with your baby — just be sure to practice the usual precautions to keep your child from getting sick: Don’t allow strangers to hold or play with your baby; keep your child away from anyone with a fever, cough, or other respiratory symptoms; and make sure you and your family wash your hands regularly.
What should you do if you think you have been exposed to or infected with measles?
Due to the highly contagious nature of measles, please contact your healthcare provider before you go to a doctor’s office or care center if you believe you have been exposed to or may be infected with measles. They will give advice on precautions to take before entering any facility to avoid potentially exposing others.
Can my child get vaccinated before they’re 12 months old?
A mother who has been immunized with the measles, mumps and rubella (MMR) vaccine or previously had measles passes on antibodies to her unborn baby. These antibodies provide protection for up to six months, and possibly longer. Babies are not routinely recommended to get the vaccine before 1 year of age because the antibodies they’re getting from their mom might interfere with how well the vaccine works before that time.
The current outbreak has not changed this recommendation. Your providers will continue to monitor guidance for vaccination recommendations if measles activity continues to rise regarding age of vaccination.
The MMR vaccine is still recommended for children 6 months and older at least two weeks prior to any international travel.
If the vaccine is so effective, and 90 percent of U.S. population has been vaccinated, why is measles spreading?
The MMR vaccine is extremely effective — about 95 to 99 of 100 people who have been vaccinated will be protected. However, measles is extremely contagious. Any place crowds of people are gathered, a person with measles could expose many others.
Unfortunately, some of those exposed may not be immune because:
- They are too young to be immunized.
- They have a medical reason why they cannot be immunized.
- They have a weakened immune system and may not be protected by the vaccine.
- Their parent/guardian chose not to get the measles vaccine for them as a child.
- They may never have received the vaccination by choice.
- They are one of the rare few for whom the vaccine didn’t work.
For these reasons, measles can quickly spread through a population when unvaccinated or susceptible persons are exposed. This is why staying up to date on vaccinations is so important: Vaccines break the chain of transmission.
Is the measles vaccine safe?
Yes. Like any medicine, vaccines do have side effects, yet scientific studies have long confirmed the safety of the MMR vaccine. Concerns about vaccines causing autism have been addressed by dozens of scientific studies and have shown that children who receive vaccines are at no greater risk for developing autism than those who do not receive vaccines.
On the flip side, children who do not receive vaccines are at increased risk of suffering from a vaccine-preventable disease.
Get more information about measles and the MMR vaccine from CHOP’s Vaccine Education Center.
- Watch "Doctors Talk: Measles"
- A Look at the Measles, Mumps and Rubella (MMR) Vaccine
- Measles: What You Should Know (Q&A) in English | Spanish | Japanese
- News & Views: What Should I know About the New MMR Vaccine, PRIORIX?
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Measles (Rubeola)
Measles, also called rubeola, is a viral illness that usually consists of a fever with cough, runny nose and pink eye (conjunctivitis), followed by a distinct rash.