Category: Vaccine Education

Do Pertussis Vaccines Work Against Pertactin-Negative Pertussis Bacteria?

Whooping cough is back!
This is not the first time that whooping cough has come back. We also saw a rise when folks got scared to use the DTP vaccine in the 1970s and 80s.

Pertussis vaccines aren’t perfect.

Few people claim that.

But what’s the problem with them?

Most experts think that the main issue is waning immunity.

While the acellular pertussis vaccines (DTaP and Tdap) that replaced the more effective whole cell pertussis vaccine (DTP) do work, the immunity they provide does not last as long as we would like.

They still work better than not getting vaccinated at all though.

Pertactin-Negative Pertussis Bacteria

What about the fact that we are starting to find pertactin-negative pertussis bacteria?

Does that mean that Bordetella pertussis, the bacteria that cause pertussis or whooping cough, have mutated and are causing a pertussis resurgence because they are resistant to the vaccine?

“CDC is currently conducting studies in the United States to determine whether pertactin deficiency is one of the factors contributing to the increase in the number of reported pertussis cases. CDC will continue to closely monitor the situation and evaluate all available scientific evidence before drawing any conclusions. There is also no suggestion that these new strains are causing more severe cases of pertussis.”

CDC on Pertactin-Negative Pertussis Strains

While an interesting theory that the anti-vaccine movement has latched on to, the answer seems to be no.

While pertactin-negative pertussis are certainly a thing, there is already evidence saying that they are not driving pertussis outbreaks – evidence that anti-vaccine folks like to ignore:

  • pertactin is only one of the components (antigens) of the pertussis bacteria that are in pertussis vaccines that help them to induce immunity. Others can include filamentous hemagglutinin, chemically or genetically detoxified pertussis toxin, and fimbrial-2 and fimbrial-3 antigens.
  • pertussis vaccines continue to be effective against pertactin-negative Bordetella pertussis bacteria
  • pertactin-negative Bordetella pertussis bacteria have not been found in all areas experiencing outbreaks of pertussis, as you would expect if they were driving these outbreaks
  • the first pertactin-negative Bordetella pertussis bacteria were found as early as the 1990s, long before we started using the current acellular versions of pertussis vaccines and before we started seeing an increase in outbreaks.

Also of note, pertactin-negative Bordetella pertussis bacteria do not cause more severe symptoms than pertactin-positive bacteria.

“Although pertussis vaccines aren’t perfect, vaccination remains our best prevention tool and we should continue to maintain high levels of DTaP coverage among children, sustain Tdap coverage in adolescents and increase Tdap coverage in adults and pregnant women. ”

CDC on Coughing up the Facts on Pertussis

Most importantly, it should be clear that pertussis vaccines work as we are not seeing pre-vaccine era levels of pertussis, even as we do see some outbreaks.

What To Know About Pertactin-Negative Pertussis

Pertactin-negative pertussis bacteria are not driving outbreaks of pertussis or whooping cough, and they have not become resistant to pertussis vaccines.

More About Pertactin-Negative Pertussis Bacteria

Answers to Anti-Vaccine Talking Points

Polio Vaccine - don't wait until it's too late.
You can sometimes wait too long to get a child immunized…

Anti-vaccine folks are very good at coming up with questions about vaccines.

And there is nothing wrong with that.

It is good to be skeptical about things.

Unfortunately, they tend to believe the answers that they make up and any “evidence” that agrees with their point of view (confirmation bias). They also will agree with any “expert” who agrees with them, even if 99.99% of experts don’t.

And tragically, they sometimes convince some vaccine-hesitant parents that their answers are right too.

Answers to Anti-Vaccine Talking Points

Most questions people have about vaccines have easy answers.

Anti-vaccine folks likely were not expecting answers when they came up with their “9 Questions That Stump Every Pro-Vaccine Advocate and Their Claims,” but they quickly got them, even after they came up with 9 new questions.

So folks were hardly stumped by these fallacious arguments…

“To say that the relationship that antivaccine activists have with science and fact is a tenuous, twisted one is a major understatement.”

David Gorski on How Not To Debate a Pro-Vaxxer

How about all of the graphs they made proving that vaccines don’t work?

Or the 14 studies that they think say vaccines cause autism?

It should be obvious by now that folks who push anti-vaccine misinformation have a poor understanding of science and a “poor understanding of how vaccination works.”

Parents who are hesitant about vaccinating and protecting their kids shouldn’t though.

Johns Hopkins Medicine, which includes the Johns Hopkins University School of Medicine and the The Johns Hopkins Hospital and Health System went out of their way to correct this anti-vaccine misinformation.
Johns Hopkins Medicine, which includes the Johns Hopkins University School of Medicine and the The Johns Hopkins Hospital and Health System went out of their way to correct this anti-vaccine misinformation.
  • Learn what package inserts really say and don’t say.
  • Review common contraindications to getting vaccinated, so that you can understand that there are actually very few reasons to not vaccinate your kids.
  • Understand that shedding isn’t the big risk that some folks claim it to be, certainly doesn’t cause outbreaks, and doesn’t routinely restrict kids from visiting cancer patients.
  • Know that vaccines worked to eradicated smallpox, helped control measles, diphtheria, rubella, and other vaccine preventable diseases, and have helped get us very close to eradicating polio.
  • Understand that kids get more vaccines today so that they are better protected, but that it is still not too many and that they don’t get them too soon.
  • Review why vaccine ingredients are not toxic.
  • Know that no major religion is against you getting your kids vaccinated.

Getting educated about vaccines and vaccine-preventable diseases will help you make a truly informed decision so that you don’t fall for the tactics and tropes of the anti-vaccine movement.

After all, once you get educated about vaccines, you will know that:

  • Andrew Wakefield has never been proven right
  • the movie VAXXED is pure propaganda
  • the CDC Whistleblower didn’t really blow the whistle on the CDC
  • herd immunity is real
  • they vaccinated folks at Leicester, it wasn’t all about quarantines
  • unavoidably unsafe does not mean that vaccines are dangerous
  • while almost $3.5 billion dollars have been paid out by the Vaccine Court since 1988 for about 5,555 compensated awards, it is important to understand that at least 2.8 billion doses of vaccines have been given just since 2006, and almost 80% of the compensated cases were settled, without an admission that a vaccine caused an injury.
  • the anti-vaccine movement harms autistic kids and their families
  • your pediatrician, with the CDC and Big Pharma, and doctors all over the world, are not part of a conspiracy hiding evidence that vaccines cause autism or any other vaccine induced diseases
  • while waning immunity is a problem with some vaccines, we are still in much better shape than we were in the pre-vaccine era, so even these vaccines are working, if not working perfectly well.
  • an unvaccinated child can more easily get measles, chicken pox, mumps, or pertussis because they don’t have immunity, not because we think these vaccine-preventable diseases will spontaneously pop up in their bodies.
  • natural immunity is great, as long as your child doesn’t suffer any of the complications of having a life-threatening disease.
  • you can sometimes wait too long to get your child immunized – long enough for them to get a vaccine-preventable disease that could have been prevented by a vaccine they didn’t get.

Most importantly,  realize that no matter what decision you make, no one is going to force you to vaccinate your child. You always have a choice, even if your choice is to skip or delay your child’s vaccines and put those around you at increased risk for getting a vaccine preventable disease.

What To Know About Anti-Vaccine Talking Points

Get educated about vaccines and vaccine-preventable diseases so that you will understand that vaccines are safe, necessary, and that they work, and so you will be able to counter any anti-vaccine talking point you hear.

 

Is the HPV Vaccine a Savior or the Most Dangerous Vaccine Ever Made?

I’m still surprised at the responses some parents have when I mention that it is time for their kids to get their HPV vaccine.

Despite what you might read on the Internet, the HPV vaccines are safe and necessary.
Despite what you might read on the Internet, the HPV vaccines are safe and necessary.

While most say things like, “good, I was wondering when they would start it,” a minority still use arguments that could come straight off of any anti-vaccine website or forum.

Is the HPV Vaccine Dangerous?

The HPV isn’t dangerous, but it is easy to see why some parents still think that it is.

How many myths about the HPV vaccine have you heard?

“I don’t like this vaccine… Heaven help us if we have a generation of kids who get a hepatitis B vaccine and a HPV vaccine and they think that now unprotected sex is okay…

I don’t think it is really clear that this vaccine is really as safe as they say it is and it is certainly not as dangerous as they say it is, but I recommend against it in my practice.”

Dr. Jay Gordon discussing the HPV vaccine on the Ricki Lake Show

You can rest assured that they aren’t true.

Deciding to Get an HPV Vaccine

The HPV vaccines are well studied and in continuing studies have only been found to cause mild side effects, just like most other vaccines.

Still undecided?

“The manufacturers of Cervarix and Gardasil are following patients in Scandinavia for at least 15 years to verify that protection from both vaccines lasts at least that long.”

National Cancer Institute on HPV Vaccines

Parents who are still hesitant should know that:

  • Gardasil, the first HPV vaccine, was approved by the FDA in 2006. The first phase 1 and phase 2 trials began in 1997. It has been given to over 200,000,000 children, teens, and young adults for over 10 years now all over the world.
  • while fainting might occur after vaccination, it is also not uncommon after other vaccinations and medical procedures, especially in teens. It is not a specific issue caused by the HPV vaccine or any vaccine, for that matter.
  • the HPV vaccine does not cause primary ovarian failure, venous blood clots, behavior problems, multiple sclerosis, autoimmune disorders, or any of the other serious side effects you read on the Internet
  • while the HPV vaccine won’t protect against all forms of HPV, it protects against the forms that are most likely to cause cervical cancer. Just two types of HPV, types 16 and 18, cause 70% of cervical cancers, and another two types, types 6 and 11, cause 90% of genital warts. All are included in the Gardasil vaccine and Cervarix includes the types most likely to cause cervical cancer.
  • HPV is not rare – in fact, it is the most common sexually transmitted infection in the United States. While many infections do go away on their own, spontaneously, others linger and can cause cervical cancer.
  • HPV doesn’t just cause cervical cancer though, it can also cause vaginal, vulvar, penile, and anal, and oropharyngeal cancer, and genital warts
  • the HPV vaccines seem to provide long lasting protection, although, as with any new vaccine, we won’t know just how long the true duration of protection is until the vaccines have been out even longer. So far, Gardasil and Cervarix are providing protection that lasts at least 8 and 9 years.
  • boys need the HPV vaccine too, as there are around 11,000 cases of HPV induced cancer in men each year, including anal cancer and cancers of the mouth/throat and penis.
  • you want your child to get the HPV vaccine before they are having sex, to prevent them from ever getting infected with HPV, which is why it is routinely recommended when kids are 11 to 12 years old. That they are not sexually active yet is the whole point! As with other vaccines, if you continue to wait, you might eventually wait too long, although you can still get the vaccine if they are already sexually active, even if they are already infected with HPV, as it might protect them against another strain that they don’t have yet.
  • getting the HPV vaccine does not make it more likely that a teen will have sex
  • using condoms will not prevent all HPV infections. HPV can also spread through nonpenetrative sexual contact.
  • cervical cancer is serious, with about 4,200 women dying of cervical cancer each year, even in this age of routine pap tests
  • although you may hear that the HPV vaccine has been banned in some places, it is still offered in Japan, Utah, and other places where they talk about these bans, and since 2014, at least 64 countries have added the HPV vaccine to their immunization schedule

Get educated about vaccines and get your kids their HPV vaccine series. Remember that if you start the series before your kids are 15 years old, they only need two doses of the vaccine. After 15 years, they need 3 doses.

What To Know About Deciding to Get an HPV Vaccine

The HPV vaccines are safe, they work, and are necessary, which are beliefs shared by experts and most parents who decide to get their kids vaccinated and protected against HPV.

More Information on Deciding to Get an HPV Vaccine

 

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How to Read a Package Insert for a Vaccine

The highlights of prescribing information of the package insert offers a nice summary of each section, with more details in the full prescribing information section that follows.
The Highlights of Prescribing Information of the package insert offers a nice summary of each section, with more details in the Full Prescribing Information section that follows.

Show me the package insert!

If you are going to ask for a package insert, you should know what’s in it and how it should be read.

Otherwise, it is easy to get misled by antivaccine propaganda, like when Mike Adams claimed he discovered “a vaccine document on the FDA’s own website that openly admits vaccines are linked to autism.”

He really just found the widely available vaccine package insert that said no such thing.

How to Read a Package Insert for a Vaccine

What goes into a package insert is dictated by the FDA, specifically the Code of Federal Regulations Title 21, and Section 314 of the NCVIA, after consultation with the Advisory Commission on Childhood Vaccines.

Much like the package inserts for other medicines, a vaccine package insert includes up to 17 major sections, including:

  1. Indications and Usage – what the vaccine is used for
  2. Dosage and Administration – the recommended dose of vaccine, when and where it should be given, and how to mix it
  3. Dosage Forms and Strengths – available dosage forms
  4. Contraindications – all situations when the vaccine should not be given
  5. Warning and Precautions – all adverse reactions and safety hazards that may occur after getting the vaccine and what you should do if they occur
  6. Adverse Reactions – this section includes clinical trials experience, postmarketing experience, and voluntary reports, and it is very important to understand that it is not always possible to establish a causal relationship to vaccination for these adverse effects. So just because something is listed here, whether it is SIDS, autism, drowning, or a car accident, doesn’t mean that it was actually caused by the vaccine.
  7. Drug Interactions – any reactions you might expect between the vaccine and other drugs
  8. Use in Specific Populations – can include recommendations for use in pregnancy, nursing mothers, pediatric use, and geriatric use
  9.  Drug abuse and dependence – usually blank
  10.  Overdosage – usually blank
  11. Description – general information about the vaccine, including how it was made and all vaccine ingredients.
  12. Clinical Pharmacology – how the vaccine works, including how long you might expect protection to last
  13. Nonclinical Toxicology – must include a section on carcinogenesis, mutagenesis, impairment of fertility, even if it is to say that the vaccine “has not been evaluated for the potential to cause carcinogenicity, genotoxicity, or impairment of male fertility.”
  14. Clinical Studies – a discussion of the clinical studies that help us understand how to use the drug safely and effectively
  15. References – when necessary, a list of references that are important to decisions about the use of the vaccine
  16. How Supplied/Storage and Handling
  17. Patient Counseling Information – information necessary for patients to use the drug safely and effectively

In addition to not having sections 9 and 10, some vaccines don’t have a section 13. It is not a conspiracy. Some older vaccines, like Varivax, do not have to have a section 13 per FDA labeling rules.

Myths About Package Inserts

Just as important as what’s listed in a vaccine package insert, is what the package insert doesn’t say.

Or what you might be led to believe it says.

“To ensure the safety of new vaccines, preclinical toxicology studies are conducted prior to the initiation of, and concurrently with, clinical studies. There are five different types of preclinical toxicology study in the evaluation of vaccine safety: single and/or repeat dose, reproductive and developmental, mutagenicity, carcinogenicity, and safety pharmacology. If any adverse effects are observed in the course of these studies, they should be fully evaluated and a final safety decision made accordingly. ”

M.D. Green on the Preclinical Toxicology of Vaccines

When reading a package insert, don’t be misled into thinking that:

  • you should be worried if a package insert states that a vaccine has not been evaluated for carcinogenic (being known or suspected of being able to cause cancer) or mutagenic (being known or suspected of causing mutations in our DNA, which can lead to cancer) potential or impairment of male fertility. Vaccines don’t cause cancer or impair male fertility, or female fertility for that matter. And as you probably know, many vaccines actually prevent cancer. Formaldehyde is the only vaccine ingredient on the list of known carcinogens, but it is the long-term exposure to high amounts of formaldehyde, usually inhaled formaldehyde, that is carcinogenic, not the residual amounts you might get in a vaccine over short amounts of time.
  • any vaccine actually causes SIDS or autism
  • pediatricians are trying to keep parents from reading package inserts. Your pediatrician is probably just confused as to why you want it, as the VIS is designed for parents, not the package insert. But if even if your pediatrician doesn’t hand you a package insert for each and every vaccine your child is going to get, they are readily available from the FDA and many other websites.

Better yet, just don’t be misled by anti-vaccine misinformation.

“Based on previous experience, carcinogenicity studies are generally not needed for adjuvants or adjuvanted vaccines.”

WHO Guidelines on Nonclinical Evaluation of Vaccine Adjuvants and Adjuvanted Vaccines

Vaccines are thoroughly tested for both efficacy and safety before they are approved.

It is also important to understand that the WHO Guidelines on Nonclinical Evaluation of Vaccine Adjuvants and Adjuvanted Vaccines and the European Medicines Evaluation Agency both state that mutagenicity and carcincogenicity studies are typically not required for vaccines.

Why not?

It is because vaccines have a low risk of inducing tumors.

There are also very specific guidelines and rules for when a manufacturer needs to perform fertility studies.

So, as expected, there are no surprises in vaccine package inserts. You can be sure that everything that needs to be tested to show that a vaccine is safe has been done. If it has “not been evaluated,” it is simply because it was not necessary.

Get educated about vaccines and get your family vaccinated and protected against vaccine preventable diseases.

What to Know About Reading Vaccine Package Inserts

Learn how to read vaccine package inserts so that you aren’t misled by many of the myths about what they do and don’t say, including why they are likely missing information on the vaccine’s potential to cause carcinogenicity, mutagenicity, or impairment of fertility.

More on How to Read a Package Insert for a Vaccine:

Where are the Double Blind Placebo Controlled Randomized Trials about Vaccines

Have you ever heard that there are no double-blind, placebo-controlled randomized clinical trials for vaccines?

It isn’t true.

There are many double-blind, placebo-controlled randomized clinical trials that involved:

  • flu shots
  • pneumonia shots
  • HPV vaccines
  • potential HIV vaccines
  • malaria vaccines
  • rotavirus vaccines
  • Dengue vaccine
  • Staphylococcus aureus vaccine

That’s good, because double-blind, placebo-controlled randomized clinical trials are considered the “gold standard” when you do medical research.

“Placebo Control – A comparator in a vaccine trial that does not include the antigen under study. In studies of monovalent vaccines this may be an inert placebo (e.g. saline solution or the vehicle of the vaccine), or an antigenically different vaccine. In combined vaccines, this may be a control arm in which the component of the vaccine being studied is lacking.”

WHO on the Guidelines on clinical evaluation of vaccines: regulatory expectations

Tragically, many more folks got pneumonia and died if they got the saline placebo instead of the vaccine in this study.
Tragically, many more folks got pneumonia and died if they got the saline placebo instead of the vaccine in this study.

But do they all use a saline placebo?

No, not always, which typically leads anti-vaccine types to dismiss them outright and push anti-vaccine misinformation, including that they are never done.

It seems that they aren’t worried so much about the antigens in vaccines anymore (the Too Many, Too Soon argument), but are now more concerned about other vaccine ingredients. They will only be satisfied with a saline placebo, but they must miss the part about wanting the trial to be double-blinded, which gets harder to do if the placebo doesn’t look and “feel” like the vaccine.

And they miss the part that “not always” doesn’t mean never.

Gardasil is a good, recent example of a vaccine that had a double-blind, placebo-controlled (using a saline solution without an adjuvant) trial for safety.

Others vaccine trials use a saline control too, including efficacy and safety trials for a new recombinant, live, attenuated, tetravalent dengue vaccine (it worked and had a good safety profile), a malaria vaccine (a phase I dose escalation study), a universal flu vaccine, a Staphylococcus aureus vaccine, etc.

The Ethics of Placebo Use in Vaccine Trials

So why haven’t placebo control studies been done even more routinely then?

Why isn’t every vaccine on the immunization schedule or every combination of vaccines tested using a double-blind, placebo controlled study?

“Placebo use in vaccine trials is clearly acceptable when (a) no efficacious and safe vaccine exists and (b) the vaccine under consideration is intended to benefit the population in which the vaccine is to be tested.”

Placebo use in vaccine trials: Recommendations of a WHO expert panel

Of course, the answer is that in order to do this type of study, you would have to have a very good justification for leaving many of the kids unprotected and at risk for a vaccine-preventable disease.

Instead, as is discussed in the article “Current topics in research ethics in vaccine studies,” if a vaccine is “already in use in some other country or community which is more or less comparable to site where the trial is planned, that vaccine should be used as the comparator.”

So instead of a placebo, it is more common “to give another vaccine that provides comparable benefit against another disease, or more willingly, against similar disease caused by different agents.”

When can you use a placebo control?

The article states that “placebo controls are ethically acceptable when there is no proven vaccine for the indication for which the candidate vaccine is to be tested.”

But get educated and don’t be fooled, many double-blind, placebo-controlled randomized clinical trials have been done with vaccines.

What to Know About Placebo Use in Vaccine Trials

When it is ethical to do so, placebos have been used in vaccine trials, even saline placebos.

More on Placebo Use in Vaccine Trials

Which Vaccines Are Vegan

The rabies vaccine is made with gelatin. Are you going to skip it if your vegan child is bit by a rabid dog?
This rabies vaccine is made with gelatin. Are you going to skip it if your vegan child is bit by a rabid dog?

Vegans do not eat meat, fish, poultry, etc., and also do not use animal products or their by-products.

So in addition to eating a plant-based diet, like vegetarians, you also don’t eat eggs or cheese, drink milk, or wear leather, etc.

Are Vaccines Vegan?

Since many vaccines contain some ingredients, like gelatin, that are derived from animals, they aren’t considered to be vegan.

Still, since there aren’t many vegan vaccines, it isn’t possible or practical to avoid getting vaccinated, so most vegans do seem to get their families vaccinated and protected against vaccine-preventable diseases.

Although people argue both ways, you should consider that:

  • many medicines, like Tamiflu, aren’t vegan, so what happens if you get sick with a vaccine-preventable disease?
  • many of the ingredients in vaccines that aren’t considered to be vegan are removed in final processing and aren’t present in the final vaccine, except in residual amounts
  • vaccines save lives, both human lives and animal lives
  • if you are not vaccinated and you get sick, you put others at risk for getting sick too

And mostly understand that just like people abuse religious exemptions and medical exemptions, many vegans don’t vaccinate solely because they are against vaccines.

Which Vaccines Are Vegan

So are any vaccines really vegan?

A newer flu vaccine, FluBlok, definitely is. It is produced using an insect cell line and grown in serum-free medium.

What To Know About Vaccines and Vegans

You can be vegan and feel comfortable about your decision to get your family vaccinated and protected against vaccine-preventable diseases. You can be a pro-vaccine vegan.

More About Vaccines and Vegans

 

Measles Vaccines vs Measles Strains

Most people understand that for every virus or bacteria, their can be multiple strains of the same organism that cause disease.

For example, there is flu A and B, swine flu, bird flu, and even dog flu.

In the case of flu, those different strains are a problem, because having immunity to one, doesn’t mean that you will have immunity to others. In fact, usually you won’t, whether it is natural immunity from a previous infection or immunity from a vaccine.

Pains with Strains

Do we have the same issues with other diseases?

We certainly have situations in which vaccines don’t cover all disease strains, including:

  • Gardasil – now covers nine strains of HPV that cause 90% of cervical cancers
  • Hib – only covers Haemophilus influenzae type b, which causes invasive disease, like meningitis, pneumonia, and sepsis, but not other Haemophilus influenzae strains that can cause ear infections
  • Polio – originally protected against three serotypes of polio, but monovalent (one strain) and bivalent (two strains) oral poliovirus vaccines have also been available to respond to outbreaks and bOPV is the one used for routine immunization, except in industrialized, polio-free countries that use the IPV shot
  • Prevnar – now covers 13 strains of Streptococcus pneumonia
  • Rotavirus – protects against severe disease caused by rotavirus strains that aren’t even in the vaccine

Fortunately, even when a vaccine doesn’t cover all strains, it does cover those that most commonly cause disease.

Measles Genotypes

Knowing the genotype of a measles strain can help you understand where measles outbreaks are coming from.
Knowing the genotype of a measles strain can help you understand where measles outbreaks are coming from.

What about measles?

There are at least 24 different genotypes of measles that come from 8 different clades (A-H), with even more wild type virus strains (based on those genotype).

These genotypes include A (all vaccine strains are genotype A), B2, B3, C1, C2, D2, D3, D4, D5, D6, D7, D8, D9, D10, D11, G2, G3, H1, and H2.

In general, genotypes are restricted to a specific part of the world, such as:

  • African Region – B2, B3
  • Eastern Mediterranean Region – B3, D4, D8
  • European Region – D4, D5, D6
  • Southeast Asian Region – D4, D5, D8, D9, G2, G3, H1
  • Western Pacific Region – D5, D9, G3, H1

In countries that have eliminated measles, like the United States, the genotypes that are found will depend on from where the measles strain was imported.

Additionally, five genotypes, B1, D1, E, F, and G1 are now inactive.

Measles Strains

Specific strains of measles viruses include the vaccine strains (Edmonston, Moraten, Zagreb, Schwarz, AIK‐C, CAM, Leningrad-16, and Shanghai-191, etc.) plus wild strains, like:

  • MVi/NewYork.USA/94 – a wild strain of B3 genotype
  • Johannesburg.SOA/88/1 – a wild strain of D2 genotype
  • Manchester.UNK/30.94  – a wild strain of D8 genotype
  • Hunan.CHN/93/7 – a wild strain of H1 genotype

Why so many vaccine strains?

It may come as a surprise to some people, but the whole world doesn’t use the same vaccines. For example, unlike the United States, Japan has used measles vaccines derived from AIK‐C, CAM, and Schwarz strains of the measles virus.

And just how many wild strains of measles are there? It’s hard to know, but consider that a study of 526 suspected measles cases from 15 outbreaks over 3 years in one state of India found at least 38 different strains.

Myths About Measles Strains

Do the measles vaccines cover all of the measles strains that cause outbreaks around the world?

Yes they do, despite the myths you may hear about mutated measles strains.

This came up a lot during the Disneyland measles outbreak, when folks first tried to place blame on a vaccine strain and then on the fact that the outbreak strain didn’t match the vaccine strain.

“…California patients were genotyped; all were measles genotype B3, which has caused a large outbreak recently in the Philippines…”

CDC Measles Outbreak — California, Dec 2014–Feb 2015

And it is coming again in the latest measles outbreak in Minnesota. Could that outbreak be caused by a vaccine strain? Anything is possible, but it’s not. A communication’s director for the Minnesota Department of Health has confirmed that “that the virus strain making people sick in this outbreak is the B3 wild-type virus.”

Of course, none of these outbreaks are started by a vaccine strain of measles shed from someone who was recently vaccinated. It also had nothing to do with the fact that the strains didn’t match – after all we aren’t talking about the flu.

These outbreaks are imported from other countries by folks who typically aren’t vaccinated or are incompletely vaccinated and mostly spread among other people who are unvaccinated.

So what’s the most important thing to understand when considering all of these vaccine strains and wild strains of measles? It is that “there is only 1 serotype for measles, and serum samples from vaccinees neutralize viruses from a wide range of genotypes…”

In other words, the measles vaccine works against all strains of measles in all genotypes of measles. That makes sense too, because the measles virus, unlike influenza, is monotypic.

There is only one main type of measles virus, despite the many small changes in the virus that can help us identify different strains and genotypes. And these changes don’t affect how antibodies protect us against the measles virus.

What To Know About Measles Strains

The best way to get protected against all measles strains is to get vaccinated with two doses of the MMR vaccine.

More About Measles Strains

Updated May 23, 2017