Measles: The Disease and Vaccination
by Tara Zandvliet, MD
Measles is a deadly disease that is very contagious. "In the old days, everyone had measles and most of them did fine with it" is the usual thought, but approximately 400 children a day still die of measles in the world. It is also one of the most contagious diseases out there, so if you are anywhere near a child with measles and you are not vaccinated, you are almost guaranteed to be infected. Measles was almost universal before the vaccine, and fell to about 150 cases a year in the US baseline afterward, mainly due to cases coming to the US from other countries. In 2014, we have had over 900 cases, so there is an upsurge in incidence that needs to be addressed.
Measles starts with fever, runny nose, sore throat, red and itchy eyes, and a cough. It generally looks like a cold. It can also have diarrhea and ear infection. Then the rash comes a week or two later. The rash starts at the hairline and temples, and then spreads to the face and chest and eventually all over the body. The skin feels like it is burning and raw, and patients have headaches, burning eyes, and body aches and generally feel miserable. About 1 in 1000 will get encephalitis, when measles infects the brain. This is 50% fatal. About 1 in 1000 get pneumonia when the measles infects the lungs, which also can be fatal. So the overall death rate is about 1 in 1000. (Compare this to chicken pox, another formerly universal childhood disease, which has a death rate of about 2-3 per 100,000, almost all adults). The encephalitis from measles is severe, and if the child survives, there is a high rate of deafness and developmental disabilities as well. There is a rare but horrendous condition that can occur with measles, which is a slow chronic brain infection with the virus called SSPE. It seems as though the patients come through the measles fine, but then about 10 years later they begin to degenerate in brain function. After about 10 years of steady decline and becoming unable to speak, eat or move, they die.
Contrary to popular belief, there is no treatment for measles. There is not a thing we doctors can do for your child who contracts the disease. You can give fever reducers and pamper them, we can give IV fluids if they can't eat, but there are no medicines that treat the virus itself. Neither antibiotics nor modern miracles work. The death rate is basically the same as it was earlier, and deaths occur despite the "best of modern medicine". Many think the death rate is old news and that with our great medical care here in the US, no kids would really die. This is completely wrong. We have had children die of measles as recently as 2010 here in the US with the best of care. Worldwide, over 400 children die of measles each day. Over 145,000 people died of measles last year alone. If the virus attacks the brain, it is just like West Nile or Rabies. Lethal.
The measles vaccine is a live virus vaccine. The vaccine makers took the measles virus and weakened it, creating a new strain that is not deadly, and rarely causes any disease. Occasionally the vaccine virus will cause "mini-measles" with a 3 day course of runny nose, red eyes, cough and rash. As it does not cause any deaths, nor is very serious, the vaccine is safer than having measles. It is approximately 95% effective with one shot if that shot is given alone. A booster shot is often given to catch the other 5%. Those people who have gotten measles despite both shots are very rare, and often were given the shots at the wrong ages or had a severe illness or many shots given at the same time, diluting the immune response to the vaccine. A second shot is not necessary if you get a blood test called a titer to confirm that the first shot protected you fully.
We vaccinate everyone in order to have what is called "Herd Immunity". If there is one person who is not vaccinated, perhaps because of a medical condition, or if there is someone for whom the vaccine didn't work, that person is protected from measles because everyone around has been vaccinated and can't bring home the disease. Or, if a person gets measles but if everyone around the person is immune, measles can't spread.
Despite what you may hear, children are not contagious after the measles shot even though it is a live virus. They do not shed the virus by coughing, sneezing, or shed it in their stool. They are not a threat to any people at home who have a weak immune system, like people on chemo, pregnant women, newborns, people on medicine that suppress the immune system like for rheumatoid arthritis or multiple sclerosis, or people born with an immunity disease. In addition, because they are not shedding the virus, and are not infecting them with a measles-like virus, so they are not protecting any of the people around them either. The thought had been that if one person gets the vaccine, and they shed the virus to the people around them, that those other people get the mild measles virus and are then immune also, so they wouldn't have to get the vaccine themselves. This does not happen. The only way to be protected from measles is to have the actual disease or to get the vaccine.
The measles vaccine is cultured in chicken embryo cells. So it contains some chicken proteins and should be given cautiously to those with egg and chicken allergy. Cow fetus proteins, as well as chick embryo cells are used in the making of the vaccine so it is not vegetarian. The culture to grow the vaccine contains sorbitol, gelatin and human albumin (protein). Neomycin (an antibiotic) is added to the culture, but not added to the actual vaccine, so the amount in the vaccine is very small (25 micrograms per dose). There is no preservative added. No thimerisal, mercury or aluminum. No formaldehyde either.
Side effects of the vaccine, if any, are usually mild - fever, rash, irritability, runny nose, generally feeling sick. There may be a local infection at the site of the injection, or bruising. The more serious side effects that occasionally occur are high fever which could cause a seizure (but not epilepsy or repeated seizures), "mini-measles", or an allergy. Deaths have been reported due to mainly a severe allergy.
Infants under a year old usually have passive immunity to measles from their mothers. It begins to wane at about 9 months. However if the shot is given that young, the effectiveness is less than 95%, so it is worth waiting to vaccinate until the child is 1 year old to get full immunity from the vaccine. The MMR vaccine appears very effective if given alone at 12-14 months. 14-21 months is the brain's critical period for development of social interaction and speech. If given after this period, the vaccine is even less likely to trigger any of the recently discovered latent genetic tendencies for developmental problems. (Other triggers include viral infections and traumas). If the first vaccination was not given at 1 year, the second best time to give the first vaccination is at 2 years old. The second vaccination (booster) can be given anytime between 4 and 6 years old. It is not considered "late" or "delayed" until the child is over 6 years old. This is because of the enormous protection of the first shot. Giving the booster shot alone is not as important as giving the first one alone. There is no longer a separate vaccine for measles only. There is only the combination vaccine of MMR (Measles, Mumps and Rubella).
There is no causal relationship between the MMR vaccine and Autism. Preliminary research is discovering autism has some genetic basis (at least one gene has been found), with a primer (environmental condition in utero or pre-conception in the parents) and then a trigger (vaccine, illness, trauma) to the child within the critical developmental window of 14-21 months. It is at least a 3 phase process, and while any vaccine could ultimately be the trigger, so could a common cold. More information will be forthcoming, I am sure, as more research is done.
Therefore, I do not doubt that some cases of autism were triggered by the MMR vaccine, but not caused by it, and some cases of autism were blamed on MMR, even though it wasn't the trigger, since it is the shot that is normally given right before autism would be diagnosed. Autism is usually diagnosed between 18 months and 3 years old, since that is when the children start to really interact, communicate with others, and understand nonverbal cues and social cues. So when it is diagnosed, people look for a cause, and the MMR has often been given just before the diagnosis. Because any vaccine could be a trigger if the genetic and other components are present, I do not recommend giving any vaccines between the ages of 14-21 months. I do not worry about giving vaccines at any other time of life in terms of autism risk.
One very important thing to note: An unvaccinated child is not a threat to your child if your child or you have been vaccinated. If an unvaccinated child is not sick, clearly the child is not a risk to anyone. If other children do get measles, they can only infect those that have not been fully immunized - infants under one year old whose passive immunity from mom has worn off, those whose families have chosen not to vaccinate, and those who can't get vaccinated or for whom the vaccine did not provide immunity. If you come in contact with someone who has measles, like the thousands at Disneyland, you will not become sick if you have been vaccinated. That's why there were not thousands of cases from the Disneyland outbreak. Most people there were already protected. The more people that are vaccinated, the smaller the outbreak.
Let me repeat that: If your child is vaccinated, then an unvaccinated child, even the one with measles, cannot infect your child and is not a danger to your child. You do not need to worry about your school's measles vaccination rate if you get your own children vaccinated.
Overall, given the upsurge in measles cases, I feel the small risk of MMR vaccination is outweighed by the benefit of protecting children against this disease.