Q&A with Dr. Chan: State epidemiologist answers your measles questions

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We like to get answers when we can. Here are answers to one reader’s measles questions.
State Epidemiologist Dr. Benjamin Chan.
State Epidemiologist Dr. Benjamin Chan.

MANCHESTER, NH – On April 29 the NH Department of Health and Human Services issued an alert regarding a case of measles in which an international exchange student from Massachusetts visited a Portsmouth restaurant. The alert was precautionary, says state epidemiologist Dr. Benjamin Chan.


Click here to read: Health Department alert: Measles exposure at NH restaurant

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That warning, posted on our site around noon on Wednesday was our top story for the day with thousands of clicks and hundreds of shares and comments on Facebook.

Among them were questions posed by reader Laura Condon, who is director of advocacy for the National Vaccine Information Center, via our online forum. Manchester Ink Link forwarded her questions to Dr. Chan, who responded Thursday with the following information:


Q: Which strain of measles was it? The wild strain or the vaccine-derived strain?

Dr. Chan: This was an international traveler, an unvaccinated exchange student coming from Western Europe where measles is circulating, so this would be the “wild” kind.

To clarify, there is no evidence I’m aware of that a measles vaccine causes measles, as polio vaccine could. The reader could be referring to attenuated symptoms you see in some people, where some of the symptoms from the vaccination can resemble the measles disease, such as fever or rash and joint pain. But we don’t think of that person as having measles, rather it’s the body’s immune system reacting to the vaccination.

Q. Was it the result of vaccination?

Dr. Chan: As answered in the previous question, no, it was due to somebody who was unvaccinated.

Q. If NH DHHS does not report on vaccination status the assumption is they don’t want to admit vaccine failure. Vaccination status is usually only mentioned if the person is unvaccinated.

Dr. Chan: It has been confirmed by the Massachusetts Department of Health that this individual was unvaccinated.

Q: Was this a young adult? This is the age that most measles cases are now occurring. In those who have been “fully vaccinated.” Vaccines do not result in true, life-long immunity. One shot didn’t work. Two shots don’t last. Now we have a young adult population at risk of an illness that is mild for children but more serious for adults.

Dr. Chan: That is a false statement. I don’t have specific information about the age of person except that it was an exchange student, which would indicate older teenager or young adult. But the point about the vaccine not producing lifelong immunity is false. What the reader is questioning is if a decade or two down road someone checks their immune status, sometimes antibodies will show as negative, but that person is still considered immune. Vaccination status trumps serologic evidence in a health care setting, where there is high risk of measles being transmitted. If a doctor or health care provider has documented evidence of two doses of MMR vaccine, that’s sufficient to document immunity.  Even if you were to test for antibodies, and if it came back negative, but there’s documentation that person got a vaccine, they are considered immune.

Q: Not sure what the 1957 date is all about. There was no measles vaccine before 1963. We all got natural measles and have had life-long immunity.

Dr. Chan: Your reader answered her own question here, but I’ll elaborate. If you were born before 1957, it’s assumed everyone before that year got measles naturally and should be immune. Those born later than 1957, even though there was not necessarily a vaccine until 1963, we still don’t assume somebody got measles between 1957 and 1963. So that five-year span is a buffer zone. Anyone who had measles before 1957 is considered immune.

Q: The CDC admits the measles vaccine used from 1963 to 1968 was a failure. So no “effective” vaccine before 1968. People were still developing measles and measles immunity … or was the disease experiencing a significant and natural decline like all illness during that time period?

Dr. Chan: That’s a nuance to vaccine recommendations we didn’t go into in the press release. The vaccine first introduced in 1963 was made from both killed and live vaccines. The killed version proved to not be effective, and so there’s a caveat that anyone who can show documentation of vaccination is immune – except for those vaccinated between 1963-1968, in which case we recommend they be revaccinated.

It was a brief period of time, and the current MMR is highly effective. One dose is 95 percent effective; two doses are 99 percent effective. The measles vaccine is one of the best we have, compared to the flu vaccine which we get every year, and on a good year, it may be only 50 percent effective.

Q: It is unfortunate that measles hysteria has spread to NH.

Dr. Chan: I wouldn’t say it’s hysteria. Rather, we’re being very cautious, for good reason. Before the measles vaccine was introduced, there were upwards of 5,000 U.S. cases a year. Some did have complications, which includes in children: pneumonia, encephalitis, and life-long deficits. People died from measles. It’s one of our great vaccine success stories. After it was introduced we saw a dramatic decline in the disease, and in the year 2000 it was declared eliminated in the U.S.  It’s still circulating in other parts of world, like Africa and Europe, and we’re now seeing it start to come back to the U.S. from imported cases and circulated in our country.

The reason we need to be cautious is measles is one of the most contagious infections out there. It’s spread easily through the air. Unlike some viruses where you have to be up close and coughing in someone’s face, measles can remain suspended in the air for up to two hours after someone leaves the room. If someone has measles in a household where everybody hypothetically is not immune or vaccinated, 90 percent of those will get the disease, so it’s highly infectious and complications can be severe. The thing is we have an easy and very good prevention strategy.

Manchester Ink Link: Do we have state statistics on the number of children opting out of vaccinations given the current trend among some circles?

Dr. Chan: We do have data on school children.  We have a medical and religious exemption here to vaccinations here in New Hampshire, not philosophical. Although there are some who should not get vaccinated, such as those who are pregnant or compromised in some other way because it is a live vaccine, there is no philosophical exemption. And we do have very good school vaccination rate. In fact, New Hampshire is No. 1 in the country for preschool- age vaccination rate – 96.3 percent of our children are immunized, based on 2013 data.

What we don’t have in New Hampshire is good data on immunization of our adults, that’s something we’re trying to implement, an immunization registry. We’re the only state in the country that doesn’t have an immunization information system, or registry. Of course, the benefit of that is that, in a situation like this one,  where there is a case of measles or other vaccine-preventable disease or outbreak, we’d have more information to know how susceptible our population is, which is another reason we reached out to the community to make them aware of the science and symptoms of measles on Wednesday. 


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About Carol Robidoux 5600 Articles

Journalist and editor of ManchesterInkLink.com, a hyperlocal news and information site for Manchester, NH.