Could Those Vaccinated for MMR Put Others at Risk? Measles Update.

measles rash on face of infant patientWe reached a point with polio eradication where the only cases of polio were those acquired from the oral live polio vaccine. It was at that time a couple decades ago that we switched to the slightly less effective injectable polio vaccine (IPV). We still have not had a single new case of polio in the USA acquired here since 1979.

The MMR is a vaccine with three live viruses- measles, mumps, and rubella. In our race to eradicate these diseases, might we be reaching a point where the vaccine is contributing as much to the disease we are seeing as the wild type diseases they are intended to prevent? I don’t have the answer to that question, but it may be time we start looking at the sources of the measles cases we are seeing.

In the study, “Detection of Measles Virus RNA in Urine Specimens from Vaccine Recipients,” (which you can read here…) measles virus RNA was detected as early as 1 day or as late as 14 days after vaccination. This study was on individuals who received the Moraten strain of measles vaccine as measles-mumps-rubella vaccine. Authors point out that, “the changing epidemiology of measles, in the form of mild measles cases in previously vaccinated individuals, suggests that more asymptomatic or subclinical cases might be occurring. The frequency of such infections, which would not meet the standard case definition of the Centers for Disease Control and Prevention, is not known. Also, it is not known whether individuals who do not display the full range of clinical signs characteristic of measles infection are capable of transmitting the virus to other susceptible individuals. In one previous study, urine samples from 5 of 12 measles case contacts were positive for measles virus antigen even though only 1 of these 5 contacts developed clinical signs.”

I would add that we no longer know to what extent, measles transmission may occur to vulnerable individuals such as those who are immunocompromised, by recently vaccinated children. Clearly they are shedding live virus. It makes a joke of the laws being enacted such as the recent California SB 277 that would exclude the unvaccinated or partially vaccinated, but would allow all the adults who work in the schools who may bring infections into the school and clearly allows those recently vaccinated and shedding live virus to come to school and potentially sicken some poor immunocompromised child. The unvaccinated child they are excluding is probably the least likely to bring measles into the school, since they likely have a robust immune system.

During the recent 2014 measles outbreak, a large percentage of these cases were linked to infections arriving from the Philippines. “This year alone, there were at least 48 U.S. importations of measles from more than 30 countries — most notably, the Philippines, which saw an outbreak involving more than 47,000 cases and was the source of an estimated 22 importations to the United States.” You can read more here…

The world health organization (WHO) is implementing a massive program to reduce measles deaths. “In 2013, about 84% of the world’s children received 1 dose of measles vaccine by their first birthday through routine health services– up from 73% in 2000. Two doses of the vaccine are recommended to ensure immunity and prevent outbreaks, as about 15% of vaccinated children fail to develop immunity from the first dose.” (Read more here… ) Sadly, the program is giving the first dose too early to get a good immune response which improves as you get older.

The World Health Organization (WHO) reports that around 145,700 children worldwide died from measles in 2013, 23,700 more than in 2012. Clearly measles is still a public health challenge.

You can read more about how measles is making a comeback by following this link.


Dr. Paul




  • Janay

    Thank you so much for this information. Very informative. Your blog is something I look forward to every time you send one out.

  • Krissy Rowan

    So do I ask all my friends to give me a heads up when they give their children the MMR vaccine? How long should I keep my child away from them?

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