Tag: hiding in the herd

Which Vaccines Don’t Prevent the Spread of a Disease?

As most folks know, Dr. Bob Sears has been put on probation by the California Medical Board.

Most vaccines don't prevent the spread of diseases?
Most vaccines don’t prevent the spread of disease???

Surprisingly, that hasn’t kept him from posting dangerous misinformation about vaccines, including his latest idea that “most vaccines don’t prevent the spread of a disease.”

Which Vaccines Don’t Prevent the Spread of a Disease?

If vaccines don’t prevent the spread of disease, then how did we eradicate, eliminate, and control so many diseases?

Dr. Bob Sears actually reassured parents that measles wasn't deadly in developed countries, neglecting to mention the dozens of people who have died in outbreaks in Europe - another well-nourished population with lower vaccination rates than the U.S.
At least seven people have died in Italy with measles over the last few years. That’s not so good for Italy.

When was the last time you saw someone with small pox, rubella, diphtheria, or polio, for example?

It is true that vaccines don’t prevent the spread of some infections though.

There is tetanus, for example, but guess what?

Tetanus isn’t contagious.

Any others?

Well, unlike most other vaccines, the meningococcal B vaccines are not thought to decrease nasal carriage of the meningococcal B bacteria. So if you are vaccinated and an asymptomatic carrier of the bacteria, you could theoretically spread it to someone else, as could someone who is unvaccinated.

Still, the MenB vaccines can protect you from getting actual meningococcal B disease, and if you don’t have meningococcemia or meningococcal meningitis, you won’t expose and spread it to someone else. That’s why the MenB vaccines are especially useful in outbreak situations.

Any others? After all, Dr. Bob did say that “most vaccines don’t prevent the spread of a disease.”

Vaccines That Don’t Prevent the Spread of a Disease

There are a few other examples of vaccines that don’t prevent the spread of a disease.

“I also warn them not to share their fears with their neighbors, because if too many people avoid the MMR, we’ll likely see the diseases increase significantly.”

Dr. Bob Sears in The Vaccine Book

Of course, any vaccine that is delayed or skipped won’t work to prevent the spread of a disease.

Just like they are seeing measles outbreaks and deaths now, because of low vaccination rates, in Ukraine there were 17,387 cases of diphtheria and 646 deaths from 1992 to 1997. Also high, were cases of measles (over 23,000 cases in 1993) and pertussis (almost 7,000 cases in 1993).

And because of waning immunity, vaccines don’t do as good a job of preventing the spread of pertussis and mumps as we would like. Still, that’s only when the vaccines don’t work, and even then, as Dr. Bob says, they do work to reduce the severity of symptoms.  During recent mumps outbreaks, the rates of complications are far below historical levels. The same is true for pertussis.

Have you ever seen or heard an unvaccinated child with pertussis? It is truly heartbreaking, especially when you realize how easily it could be prevented.

We typically see the same thing with flu. Even when the flu vaccine isn’t a good match or isn’t as effective as we would like, it still has a lot of benefits, including reducing your risk of dying.

“IPV induces very low levels of immunity in the intestine. As a result, when a person immunized with IPV is infected with wild poliovirus, the virus can still multiply inside the intestines and be shed in the faeces, risking continued circulation.”

Inactivated poliovirus vaccine

Does the fact that IPV, the inactivated polio vaccine, can sometimes lead to infections and shedding mean that it doesn’t prevent infections?

Of course not!

“IPV triggers an excellent protective immune response in most people.”

Inactivated poliovirus vaccine

Most people vaccinated with IPV will be immune, won’t get wild polio, and so won’t be able to get anyone else sick.

Vaccines reduce disease by direct protection of vaccinees and by indirect protection of nonimmune persons. Indirect protection depends on a reduction in infection transmission, and hence on protection (immunity) against infection, not just against disease. If a vaccine were to protect only against disease, and not at all against infection, then it would have no influence on infection transmission in the community and there would be no indirect protection (vaccination of one person would have no influence on any others in the community). It would be possible to reduce disease with such a vaccine but not to eradicate the infection.

Plotkin’s Vaccines

But because IPV doesn’t provide indirect protection, we still use OPV in parts of the world where polio is more of a problem.

Vaccines work. Even the few that don’t prevent the spread of infections, still help to reduce disease.

What’s the Difference Between Infections and Disease?

Wait, is there a difference between infection and disease?

Yes there is, something that Dr. Bob, who actually wrote a book about vaccines, seems to have overlooked.

An infection is simply the presence of a virus, bacteria, or other organism in your body.

A disease, on the other hand, is a virus or bacteria in your body causing signs and symptoms.

All vaccines work to prevent disease, or at least they do when you actually get vaccinated.

A very few don’t prevent infections and the spread of infections, but that is not a good reason to skip or delay your child’s vaccines. In fact, it is one of the reasons why it is important to have high vaccination rates! Even natural infections don’t always keep you from becoming asymptomatic carriers that can infected others. Many people who have natural typhoid (remember Typhoid Mary?) and hepatitis B infections go on to become chronic carriers without any symptoms, but still able to infect others.

If you understand that a few vaccines don’t prevent the spread of infections, then you should understand that you can’t hide in the herd and expect to be protected, even though most folks around you are vaccinated.

What to Know About Vaccines and the Spread of Disease

Despite what Dr. Bob says, almost all vaccines work to prevent the spread of disease and infections, at least they do when you get your kids vaccinated.

More on Vaccines and the Spread of Disease

How Anti-Vaccine Are You? Take Our Quiz.

It’s easy to be anti-vaccine when you are hiding in the herd. You don’t get vaccinated and you don’t vaccinate your kids, and instead, you simply rely on the fact that everyone else around you is vaccinated to protect you from vaccine-preventable diseases.

Would you vaccinate your high-risk child?
Would you vaccinate your high-risk child? Photo by Janko Ferlic.

Of course, this is a terrible strategy, as we are seeing with the increase in cases of measles and pertussis, etc. It is much better to learn about the importance and safety of vaccines, get fully vaccinated, and stop these outbreaks.

This hasn’t seemed to have deterred most anti-vaccine “experts” yet, as they continue to spout their anti-vaccine myths and misinformation and push their anti-vaccine talking points.

But as they continue to tell you that vaccines don’t work, how about asking what they would do in these ten high-risk situations?

Amazingly, some folks continue to try and justify skipping vaccines and accept the risk of disease, even when that risk is much higher than usual and they could be putting their child’s life in immediate danger!

How will you do with our quiz?

Would you choose to vaccinate in these situations?

1. Baby born to mother with hepatitis B.

You are pregnant and have chronic hepatitis B (positive for both HBsAg and HBeAg). Should your newborn baby get a hepatitis B shot and HBIG?

Background information:
Many anti-vaccine experts tell parents to skip their baby’s hepatitis B shot, saying it is dangerous, not necessary, or doesn’t work (typical anti-vax myths and misinformation).

However, it is well known that:

  • from 10 (HBeAg negative) to 90% (HBeAg positive) of infants who are born to a mother with chronic hepatitis B will become infected
  • 90% of infants who get hepatitis B from their mother at birth develop chronic infections
  • 25% of people with chronic hepatitis B infections die from liver failure and liver cancer
  • use of hepatitis B immune globulin (HBIG) and hepatitis B vaccine series greatly decreases a newborn’s risk of developing a hepatitis B infection (perinatal transmission of hepatitis B), especially if HBIG and the first hepatitis B shot is given within 12 hours of the baby being born

Would your newborn baby get a hepatitis B shot and HBIG?

2. Your child is bitten by a rabid dog.

Your toddler is bitten by a dog that is almost certainly rabid. Several wild animals in the area have been found to be rabid recently and the usual playful and well-mannered dog was acting strangely and died a few hours later. The dog was not vaccinated against rabies and unfortunately, the owners, fearing they would get in trouble, disappeared with the dead dog, so it can’t be quarantined. Should your child get a rabies shot?

Background information:
Although now uncommon in dogs, rabies still occurs in wild animals, including raccoons, skunks, bats, and foxes. These animals can then expose and infect unvaccinated dogs, cats, and ferrets, etc.

To help prevent rabies, which is not usually treatable, in addition to immediately cleaning the wound, people should get human rabies immune globulin (RIG) and rabies vaccine.

The rabies vaccine is given as a series of four doses on the day of exposure to the animal with suspected rabies and then again on days 3, 7, and 14.

Although rare in the United States, at least 1 to 3 people do still die of rabies each year. The rabies vaccine series and rabies immune globulin are preventative, however, without them, rabies is almost always fatal once you develop symptoms. A few people have survived with a new treatment, the Milwaukee protocol, without getting rabies shots, but many more have failed the treatment and have died.

Would your child get a rabies shot? What if he had picked up a rabid bat?

3. Traveling to Romania.

You are traveling to the Romania to see family with your 9-month-old baby. Neither of you have had the measles vaccine. Should you both get vaccinated before making the trip?

Background information:

Over the past few years, over 100 people have died in measles outbreaks across Europe, with many in Romania.

Although the first MMR vaccine is routinely given when children are 12 months old, it is now recommended that infants get vaccinated as early as age six months if they will be traveling out of the country.

Since the endemic spread of measles was stopped in 2000, almost all cases are now linked to unvaccinated travelers, some of whom start very large outbreaks that are hard to contain.

Would you both get vaccinated before making the trip?

4. Tetanus shot.

Your unvaccinated teen gets a very deep puncture wound while doing yard work. A few hours later, your neighbor comes by to give you an update on his wife who has been in the hospital all week. She has been diagnosed with tetanus. She had gotten sick after going yard work in the same area and has been moved to the ICU. Do you get him a tetanus shot?

Background information:
Most children get vaccinated against tetanus when they receive the 4 dose primary DTaP series, the DTaP booster at age 4-6 years, and the Tdap booster at age 11-12 years.

Unlike most other vaccine-preventable diseases, tetanus is not contagious. The spores of tetanus bacteria (Clostridium tetani) are instead found in the soil and in the intestines and feces of many animals, including dogs, cats, and horses, etc.

Although the tetanus spores are common in soil, they need low oxygen conditions to germinate. That’s why you aren’t at risk for tetanus every time your hands get dirty. A puncture wound creates the perfect conditions for tetanus though, especially a deep wound, as it will be hard to clean out the tiny tetanus spores, and there won’t be much oxygen at the inner parts of the wound.

These types of deep wounds that are associated with tetanus infections might including stepping on a nail, getting poked by a splinter or thorn, and animal bites, etc. Keep in mind that some of these things, like a cat bite, might put you at risk because you simply had dirt/tetanus spores on your skin, which get pushed deep into the wound when the cat bites you.

Symptoms of tetanus typically develop after about 8 days and might include classic lockjaw, neck stiffness, trouble swallowing, muscle spasms, and difficulty breathing. Even with treatment, tetanus is fatal in about 11% of people and recovery takes months.

Would you get your teen a tetanus shot?

5. Cocooning to protect baby from pertussis.

Both of your unvaccinated teens go to school with a personal belief vaccine exemption. You are due in a few months and are a little concerned about the new baby because there have been outbreaks of pertussis in the community, especially at their highschool. Should everyone in the family get a Tdap shot?

Background information:
Pertussis, or whooping cough, classically causes a cough that can last for weeks to months.

While often mild in teens and adults, pertussis can be life-threatening in newborns and infants. In fact, it is young children who often develop the classic high-pitched whooping sound as they try to breath after a long coughing fit.

In a recent outbreak of pertussis in California, 10 infants died. Almost all were less than 2 months old.

Since infants aren’t protected until they get at least three doses of a pertussis vaccine, usually at age 6 months, experts recommend a cocooning strategy to protect newborns and young infants from pertussis. With cocooning, all children, teens, and adults who will be around the baby are vaccinated against pertussis (and other vaccine-preventable diseases), so that they can’t catch pertussis and bring it home.

There is even evidence that a pregnancy dose of Tdap can help protect infants even more than waiting until after the baby is born to get a Tdap shot.

Would everyone in your family get a Tdap shot?

6. Nephew is getting chemotherapy.

Your nephew was just diagnosed with leukemia and is going to start chemotherapy. Your kids have never been vaccinated against chicken pox and haven’t had the disease either. Your brother asks that you get them vaccinated, since they are around their cousin very often and he doesn’t want to put him at risk.

Do you get your kids vaccinated with the chicken pox vaccine?

Background information:
Kids with cancer who are getting chemotherapy become very vulnerable to most vaccine-preventable diseases, whether it is measles, flu, or chicken pox.

According to the Immune Deficiency Foundation, “We want to create a ‘protective cocoon’ of immunized persons surrounding patients with primary immunodeficiency diseases so that they have less chance of being exposed to a potentially serious infection like influenza.”

Would your get your kids vaccinated with the chicken pox vaccine?

7. Outbreak of meningococcemia at your kid’s college.

Your child has just gone off to college. There is an outbreak of meningococcemia in her dorm (8 cases already). It is the strain that is included in the Menactra and Menveo vaccines, although she has not been vaccinated. Do you encourage her to get vaccinated?

Background information:
Neisseria meningitidis is a bacteria that can cause bacterial meningitis and sepsis (meningococcemia).

Depending on the type, it can occur either in teens and young adults (serogroups B, C, and Y) or infants (serogroup B).

Although not nearly as common as some other vaccine-preventable diseases, like measles or pertussis, it is one of the more deadly. Meningococcemia is fatal in up to 40% of cases and up to 20% of children and teens who survive a meningococcal infection might have hearing loss, loss of one or more limbs, or neurologic damage.

Meningococcal vaccines are available (Menactra and Menveo) and routinely given to older children and teens to help prevent meningococcal infections (serogroups A, C, Y and W-135). Other vaccines, Bexasero and Trumenba, protect against serogroup B and are recommended for high risk kids and anyone else who wants to decrease their risk of getting Men B disease.

Would you encourage her to get vaccinated against meningococcemia?

8. Cochlear implants.

Your preschooler has just received cochlear implants. Should he get the Prevnar and Pneumovax vaccines?

Background information:
Cochlear implants can put your child at increased risk for bacterial meningitis caused by the Streptococcus pneumoniae bacteria (pneumococcus).

Would he get vaccinated with Prevnar and Pneumovax, as he is no at high risk for pneumococcal disease?

9. Splenectomy

Your child is going to have his spleen removed to prevent complications of hereditary spherocytosis. Should he get the meningococcal and pneumococcal vaccines first?

Background information:
Without a spleen, kids are at risk for many bacterial infections, including severe infections caused by Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis bacteria.

In addition to their routine vaccines, kids with asplenia might need Menveo or Menactra, Bexsero or Trumenba (Men B), and Pneumovax 23.

Would your child get these vaccines that are recommended for kids with asplenia?

10. Ebola

Ebola is returning, but this time an experimental vaccine is available.

Background information:
There were nearly 30,000 cases and just over 11,000 deaths during the 2014-16 Ebola outbreak in West Africa.

You are in an area that is seeing an increasing number of Ebola cases and there is still no treatment for this deadly disease. An experimental vaccine is being offered.

Do you get the vaccine?

How Anti-Vaccine Are You?

It’s easy to be anti-vaccine when you are hiding in the herd – seemingly protected by all of the vaccinated people around you.

Would you still delay or skip a vaccine in a high-risk situation?

More on The Anti-Vaccine Quiz

Comparing Lightning Strikes to Measles Deaths

Have you ever heard that your child has more of a chance of getting hit by lightning than getting measles?

Since getting struck by lightning is rare, folks like to use it in comparisons to other things that they also think are low risk when trying to make a point.

There are problems with this type of argument though.

Understanding Risk Perception

In an age when many folks are overly anxious about things, it is important to understand the difference between real and perceived risks. Unfortunately, our biases often lead us to worry about the wrong things, sometimes with tragic consequences.

“No intervention is absolutely risk free. Even the journey to a physician’s office with the intention to receive a vaccination carries the risk of getting injured in an accident. With regards to risks of vaccination per se, one has to distinguish between real and perceived or alleged risks.”

Heininger on A risk–benefit analysis of vaccination

Vaccines have risks, but they are small risks, as we know that vaccines are safe and necessary and the decision to skip or delay your child’s vaccines carries with it a much greater risk.

Comparing Lightning Strikes to Vaccine Preventable Diseases

How common or rare do you think it is to get hit by lightning?

  • odds of being hit by lightning – 1 in 1,171,000 (each year)
  • odds of ever being hit by lightning – 1 in 14,600 (lifetime risk)
  • on average, 26 people die after being struck by lightning each year (since 2007), which is down from a recent historical average of 45 deaths per year (30 year average) and way down from when we used to see 400 lightning strike deaths each year before 1950
  • on average, 252 people are injured after being struck by lightning each year
Actually, just since 2000, at least 5 people have died of measles in Canada.
Actually, just since 2000, at least 6 people have died of measles in Canada.

Although 26 people dying after lightning strikes sounds like way too many to me, especially since one recent death was a 7-year-old boy in Tennessee playing under a tree, with 1 in 1,171,000 odds of getting hit, it sounds like we are pretty safe.

But is it fair to use those odds to justify your decision to keep your kids unvaccinated?

Of course not!

Why is our risk of getting struck by lightning so low?

What happens when we hear thunder or see lightning?

When Thunder Roars, Go Indoors!

What happens when a thunder storm approaches and you are at your kids soccer or baseball game?

“Postpone or suspend activity if a thunderstorm appears imminent before or during an activity or contest (irrespective of whether lightning is seen or thunder heard) until the hazard has passed. Signs of imminent thunderstorm activity are darkening clouds, high winds, and thunder or lightning activity.”

UIL on Lightning Safety

Many ball fields now have lightning detectors to alert officials of nearby storms. And just about everyone has access to weather apps on a smart phone that can alert them to an approaching thunder storm or nearby lightning strikes.

The point is that most of us understand that lightning is dangerous, so we go far out of our away to avoid getting hit. The risk of getting hit by lightning isn’t 1 in 1,171,000 with folks running around outside waving golf clubs in the air during thunder storms or sitting on their roofs under an umbrella watching the storm.

The risk of getting hit by lightning is 1 in 1,171,000 because most of us go inside once we know lightning is nearby.

“Based on the media reports of the fatal incidents, many victims were either headed to safety at the time of the fatal strike or were just steps away from safety. Continued efforts are needed to convince people to get inside a safe place before the lightning threat becomes significant. For many activities, situational awareness and proper planning are essential to safety.”

A Detailed Analysis of Lightning Deaths in the United States from 2006 through 2017

And the same is true with measles and other vaccine-preventable diseases. They aren’t as common as they once were because most of us are vaccinated and protected.

If you skip or delay your child’s vaccines, you will increase the risk that they will get one of these vaccine-preventable diseases. And you will increase the risk that they will get someone else sick.

“I also warn them not to share their fears with their neighbors, because if too many people avoid the MMR, we’ll likely see the diseases increase significantly.”

Dr. Bob Sears in The Vaccine Book

And if enough people don’t get vaccinated, herd immunity fails, and we will see a return of pre-vaccine era levels of disease.

What to Know About Vaccines and Risk Perception

Folks often misuse lightning strikes when they think about risks, not understanding that the risk of getting hit by lightning is low because we take a lot of precautions to avoid getting hit by lightning.

More on Vaccines and Risk Perception

Are Anti-Vaccine Folks Smarter Than the Rest of Us?

For the overwhelming majority of us, it seems like a simple decision – get your kids vaccinated and protected and avoid all of the risks of vaccine-preventable diseases.

After all, we understand that vaccines are safe and necessary.

But folks who choose to skip or delay vaccines want to do what is best for their kids too, even as they come to the exact opposite decision, so who is making the smarter choice?

Are Anti-Vaccine Folks Smarter Than the Rest of Us?

Not surprisingly, anti-vaccine folks think they are smarter.

Why?

“In the end we are left with a powerful sense of knowledge – false knowledge. Confirmation bias leads to a high level of confidence, we feel we are right in our gut. And when confronted with someone saying we are wrong, or promoting an alternate view, some people become hostile.

The Dunning-Kruger effect is not just a curiosity of psychology, it touches on a critical aspect of the default mode of human thought, and a major flaw in our thinking. It also applies to everyone – we are all at various places on that curve with respect to different areas of knowledge. You may be an expert in some things, and competent in others, but will also be toward the bottom of the curve in some areas of knowledge.”

Steven Novella on Lessons from Dunning-Kruger

While it is easy to blame it on the Dunning-Kruger effect, a study that appeared in the July 2004 issue of Pediatrics, Children who have received no vaccines: who are they and where do they live?, is often used by anti-vaccine folks to reinforce the idea that they are smarter.

“Undervaccinated children tended to be black, to have a younger mother who was not married and did not have a college degree, to live in a household near the poverty level, and to live in a central city. Unvaccinated children tended to be white, to have a mother who was married and had a college degree, to live in a household with an annual income exceeding 75,000 dollars, and to have parents who expressed concerns regarding the safety of vaccines and indicated that medical doctors have little influence over vaccination decisions for their children”

Children who have received no vaccines: who are they and where do they live?

But the part of the study that is often quoted is comparing unvaccinated vs undervaccinated.

In the same study, the education level of unvaccinated vs vaccinated is virtually the same.

And the differences for the unvaccinated vs undervaccinated kids was about their living near the poverty level. If these families grew up with less money, they likely had less opportunities to go to school, and unfortunately, had less opportunities to keep their kids up-to-date on their vaccines.

One study, Maternal characteristics and hospital policies as risk factors for nonreceipt of hepatitis B vaccine in the newborn nursery, did seem to associate a higher education level with refusing the newborn hepatitis B vaccine, but an even bigger factor was being born in a facility that actually had a policy that offered the vaccine.

“Likewise, vaccine refusal now appears to be less a function of socioeconomic status than it once was. Previously, maternal education was strongly associated with vaccine refusal, but now mothers without a high school diploma are even more likely than college graduates to have unvaccinated children . Also, unvaccinated children are no longer found primarily in the highest income households (perhaps a function of income data being top-coded at $50,000), but now are equally likely to live in households with more moderate (or even below poverty) incomes.”

Laura Blakeslee on Trends and Characteristics of Unvaccinated Children in the United States : The National Immunization Survey, 2002 − 2010

Other studies have either showed a higher level of college graduates for those who vaccinated their kids or no difference.

What about all of the experts in the anti-vaccine movement? Remember that the heroes and so called experts of the the anti-vaccine movement mostly includes celebrities, some doctors and scientists who are practicing way out of their field of expertise when they talk about vaccines, and others whose work is not supported by the great majority of experts in their field.

That’s not necessarily the end of the story though.

Yet another study (a small survey), Parental Delay or Refusal of Vaccine Doses, Childhood Vaccination Coverage at 24 Months of Age, and the Health Belief Model, found that as compared to parents who vaccinated their kids, those who delayed or refused vaccines:

  • were less likely to think that vaccines were necessary
  • were less likely to think that their kids would get a disease if they weren’t vaccinated
  • were less likely to believe that vaccines are safe
  • were more likely to believe that vaccines caused serious side effects
  • were more likely to believe that children get too many vaccines

And surprisingly, considering that the above things are basically anti-vaccine talking points that are easily disproven, they were actually more likely to have gone to college and to be a college graduate. It is not a surprise that they were less likely to have a good relationship with their doctor and were less likely to believe that their doctor had their child’s best interest at heart.

Parents unknowingly gave their infants teething powder made with mercury, causing pink disease or mercury poisoning.
Parents unknowingly gave their infants teething powder made with mercury, causing pink disease or mercury poisoning. Ironically, a decrease in illiteracy levels might have been the cause.

So maybe some anti-vaccine parents are indeed well-educated about some things, but that just gets us back to the Dunning-Kruger effect, as they certainly aren’t making smart decisions about vaccines.

Fortunately, this is still a very small, although very vocal, minority of people, as most parents vaccinate and protect their kids.

What to Know About Anti-Vaccine Intelligence and Education

Parents who choose to skip or delay their child’s vaccines are not making smart decisions about vaccines.

More on Anti-Vaccine Intelligence and Education

How Can the Unvaccinated Spread Diseases They Don’t Have?

Folks who are intentionally unvaccinated often have a hard time understanding why the rest of us might be a little leery of being around them.

That’s especially true if we have a new baby in the house, younger kids who aren’t fully vaccinated and protected, or anyone with a chronic medical condition who can’t be vaccinated.

Why? Of course, it is because we don’t want them to catch measles, pertussis, or other vaccine-preventable diseases.

“How can you spread a disease that you don’t even have?”

It’s true, you can’t spread a disease that you don’t have.

But infectious diseases don’t magically appear inside our bodies – we catch them from other people. And if you have skipped or delayed a vaccine, then you have a much higher chance of getting a vaccine-preventable disease than someone who is vaccinated and protected.

So, just avoid other people when you are sick, right?

“…the increased risk of disease in the pediatric population, in part because of increasing rates of vaccine refusal and in some circumstances more rapid loss of immunity, increases potential exposure of immunodeficient children.”

Medical Advisory Committee of the Immune Deficiency Foundation

That works great in theory, but since you are often contagious before you show signs and symptoms and know that you are sick, you can very easily spread a disease that you don’t even know that you have.

An infant hospitalized during a measles outbreak in the Philippines in which 110 people died.
Children with measles are contagious 4 days before through 4 days after their rash appears, but you often don’t recognize that it is measles until they get the rash! Photo by Jim Goodson, M.P.H.

There’s the trouble:

  1. being unvaccinated, you or your child are at higher risk to get sick
  2. when you get sick, you can be contagious several days before you have obvious symptoms
  3. you can spread the disease to others before you ever know that you are sick, or at least before you know that you have a vaccine preventable disease

This makes intentionally unvaccinated folks a risk to those who are too young to be vaccinated, are too young to be fully vaccinated, have a true medical exemption to getting vaccinated, or when their vaccine simply didn’t work.

measles-santa-clara-county
Folks with measles often expose a lot of other people because they don’t yet know that they have measles and aren’t showing signs and symptoms yet.

In fact, this is how most outbreaks start. Tragically, kids too young to be vaccinated get caught up in these outbreaks.

Keep in mind that these parents didn’t have a choice about getting them protected yet. Someone who decided to skip their own vaccines made that choice for them.

And remember that while you can’t spread a disease that you don’t even have, you can certainly spread a disease that you don’t realize that you have.

What to Know About The Unvaccinated Spreading Disease

If you aren’t going to get vaccinated or vaccinate your kids, understand the risks and responsibilities, so that you don’t spread a vaccine-preventable diseases to others that you might not even know that you have yet.

More on the Unvaccinated Spreading Disease

Pertussis Outbreaks

Like measles and mumps, pertussis, or whooping cough, is another vaccine-preventable disease that has been increasing in recent years.

Pre-Vaccine Era Pertussis Outbreaks

Pertussis has been known since at least the Middle Ages, although the bacteria that causes pertussis, Bordetella pertussis, wasn’t discovered until 1906.

Like measles, pertussis was a top killer of young children in the pre-vaccine era.
Like measles, pertussis was a top killer of young children in the pre-vaccine era.

That discovery led to the later development of the first pertussis vaccines, but before then, pertussis was a big killer, with epidemic cycles every 2 to 5 years.

During one of these cycles in the United States, from 1926 to 1930, there were:

  • 909,705 cases, and
  • 36,013 deaths

Unfortunately, even natural infection doesn’t provide life-long immunity, so adults would get pertussis and give it to susceptible kids, who were most likely to die during these epidemics.

But even in non-epidemic years, a lot of folks got pertussis. The number of reported cases ranged from “just” 161,799 in 1928 to 202,210 in 1926. And during one of the biggest years, 1934, there were 265,269 cases!

Post-Vaccine Era Pertussis Outbreaks

That changed in the vaccine era.

The first pertussis vaccines were developed in the 1930s and became more widely used in the 1940s when it was combined into the whole-cell DTP vaccine.

This was replaced with the acellular DTaP vaccine in 1997, with the Tdap vaccine being added to the vaccine schedule in 2006.

These vaccines helped to greatly reduce how many people got pertussis and how many people died from pertussis:

  • 1940 – 183,866 cases
  • 1950 – 120,718 cases and 1, 118 deaths
  • 1960 – 14,809 cases and 118 deaths
  • 1970 – 4,249 cases and 12 deaths
  • 1980 – 1,730 cases and 11 deaths
  • 1990 – 4,570 cases and 12 deaths
  • 2000 – 7,867 cases and 12 deaths
  • 2010 – 27,550 cases and 26 deaths

They never eradicated pertussis though, and as you can see, recently, pertussis cases have started to rise again.

Is it a coincidence that whooping cough came back as more folks began to skip and delay vaccines for their kids?
Is it a coincidence that whooping cough came back as more folks began to skip and delay vaccines for their kids?

In 2012, there were 48,277 cases of pertussis in the United States, the most since 1950, when we had 68,687 cases. Unfortunately, with the rise in cases, we are also seeing the tragic consequences of this disease – 20 deaths in 2012, mostly infants under age 3 months.

Pertussis cases remained steady, but high, in 2013 and 2014, at around 30,000 cases in the United States.

In California, pertussis reached epidemic levels. The California Department of Public Health reported at least 11,114 cases in 2014 – the highest numbers of pertussis cases in the state in 70 years!

And as expected with the rise in cases, there were 3 pertussis related deaths in California that year – all infants who had contracted pertussis when they were less than 8 weeks old. Two of the infants became sick in 2013, but the third, a 5-week-old baby, got infected in 2014.

Another baby, only 25 days old died in early 2015, but will be counted as the 2nd death of 2014 since that is when the illness started. About 383 patients, mostly infants who are less than 4 months old, were hospitalized in California that year, including 80 who required intensive care. And according to the California Department of Public Health, about 82% of the cases in infants were born to mothers who did not receive a dose of Tdap during their third trimester of pregnancy.

What’s happened since then?

Pertussis cases are continuing to fall each year! In fact, with about 16,000 cases in the United States, 2017 may have ended with the lowest number of pertussis cases since 2008.

Still, with just 1,830 pertussis cases in California in 2016, there were two deaths – both infants who were younger than 3 months of age when they got sick. And there was at least one death in 2017, with similar rates of disease, although reports are still preliminary.

Why So Many Pertussis Outbreaks?

Ever since a 2010 California pertussis outbreak, in which there were 9,154 cases of pertussis, the most in 63 years, and 10 infants died, many people, especially parents, began wondering why we were seeing more pertussis these days.

Is it because the pertussis vaccines simply don’t work, as the anti-vaccine movement would have you think?

Or is it because there are higher rates of unvaccinated kids these days and parents using alternative immunization schedules, instead of the standard immunization schedule from the CDC?

James Cherry, MD is an expert on pertussis and pertussis vaccines.
James Cherry, MD is an expert on pertussis and pertussis vaccines.

A commentary, Why Do Pertussis Vaccines Fail?, by James Cherry, MD, gave us some answers.

While the title of the article might have you think that all of the blame lies with the pertussis vaccines, that certainly isn’t the case. While there can be vaccine failures with the pertussis vaccines, just like any other vaccine, that doesn’t mean that the vaccine doesn’t work for most children.

One of the problems is that the DTaP vaccine likely isn’t as effective as the older DTP vaccine. So instead of efficacy of 84 to 85%, as was once believed, it is likely closer to just 71 to 78%.

Other issues, including waning immunity, the possibility of an incorrect balance of antigens in the vaccine that could create a blocking effect, and genetic changes in the B. pertussis bacteria, could also possibly lead to increased vaccine failure rates.

So it isn’t that the pertussis vaccines don’t work.

That should be easy to see when you look at the pertussis rates in California, when the highest rates by far were in infants less than 6 months of age (434 per 100,000 people). In contrast, children who were 6 months to 6 years old had a rate of only 62 per 100,000.

And the results of a study that were presented at the 49th annual meeting of the Infectious Diseases Society of America in Boston show just how important the pertussis vaccine is, as:

  • vaccine effectiveness was 98.1 percent among children who received their 5th dose within the past year
  • long term effectiveness – children who were five or more years past their last DTaP dose – was about 71 percent
  • children who had never received any doses of DTaP (unvaccinated children) faced odds of having whooping cough at least eight times higher than children who received all five doses

It is also important to note that the high rates seen in 2010 in California are still well below the rates that were seen in the pre-vaccination era, when the attack rate of pertussis in the United States was as high as 157 per 100,000 people, with about 200,000 cases a year.

What’s the answer?

“The present “resurgence of pertussis” is mainly due to greater awareness and the use of PCR for diagnosis. There are also many other factors which have contributed to the “resurgence.” New vaccines are clearly needed; with our present vaccines (DTaP and adolescent and adult formulated tetanus and diphtheria toxoids and acellular pertussis vaccine (Tdap)), if used correctly, severe pertussis and deaths in infants can be prevented.”

James D. Cherry, MD on The History of Pertussis (Whooping Cough); 1906 – 2015: Facts, Myths, and Misconceptions

It certainly isn’t for more kids to follow non-standard, parent-selected, delayed protection vaccine schedules or to simply skip vaccines all together. Since natural immunity isn’t going to keep newborns and infants from getting pertussis, the ages which are most at risk for life-threatening infections, they can catch pertussis from people around them, including those working on their natural immunity. Natural infections don’t even provide life-long protection against pertussis, as some people believe. That natural immunity wanes fairly quickly too.

Not Vaccinated? No Kisses!
Not Vaccinated? No Kisses!

The future of pertussis control is more likely going to be in maximizing our current vaccination program, including getting more teens and adults to get the Tdap vaccine, especially when women are pregnant.

That’s the best strategy, at least until new pertussis vaccines are developed. It provides a lot of benefits. According to the CDC, like with the flu vaccine, when you get a pertussis vaccine, in addition to protecting yourself and those people around you, “people who do catch whooping cough after being vaccinated are much less likely to be hospitalized or die from the disease.”

Unfortunately, not everyone has gotten the message. And because of waning immunity, children who aren’t vaccinated against pertussis can’t “hide in the herd” and rely on the rest of us who do vaccinate our children to provide them with protection. Instead, since they are at a higher risk, they get pertussis and get even more people sick.

This slogan, during a whooping cough epidemic, reminded parents to get their kids vaccinated now.
This slogan, during a whooping cough epidemic, reminded parents to get their kids vaccinated now.

In one study, Parental refusal of pertussis vaccination is associated with an increased risk of pertussis infection in children, researchers found that “vaccine refusers had a 23-fold increased risk for pertussis when compared with vaccine acceptors, and 11% of pertussis cases in the entire study population were attributed to vaccine refusal.” The highly contagious nature of pertussis then means every primary case is probably going to infect as many as 17 other people. That’s why it makes sense that higher rates of children using vaccine exemptions could be at least one of the factors in these outbreaks.

In fact, several studies, including, Geographic Clustering of Nonmedical Exemptions to School Immunization Requirements and Associations With Geographic Clustering of Pertussis, found that “geographic pockets of vaccine refusal are associated with the risk of pertussis outbreaks in the whole community.”

Get educated. Vaccines are safe and as you can see with the rise in outbreaks, vaccines are necessary.

What to Know About Pertussis Outbreaks

Many factors are responsible for the rise in pertussis outbreaks in recent years, but it is clear that being unvaccinated and unprotected put you at greatest risk for getting pertussis and passing it on to others.

More on Pertussis Outbreaks

Ask Amy About Intentionally Unvaccinated Kids at a Holiday Party

How do you avoid fighting with friends and family when you get together at the holidays?

Some say to talk about whatever you want, but just have empathy for others when you talk about controversial topics.

Other experts say to simply avoid talking about things like politics, religion, and sex.

Going that route, it is easy to imagine that the list of things that you can’t talk about can get pretty long in some families.

Topics Too Dangerous To Avoid

Are some topics too dangerous to avoid talking about?

I’m not talking about in the long-term, what’s going to happen to our world kind of dangerous, but short term dangers to your kids and the rest of your family.

For example, what if you instinctively think that you should avoid talking about guns when visiting your uncle’s house, because you remember seeing all of his Facebook posts about the NRA. But you want to make sure there aren’t any unsecured guns lying around the house that your toddler could find. Do you ASK about guns in the house?

Ask Amy About Intentionally Unvaccinated Kids

What about vaccines?

That’s another topic that’s too important to avoid talking about.

Ask Amy took on the issue of the risk of an intentionally unvaccinated child to the rest of the family.
Ask Amy takes on the risk of an intentionally unvaccinated child at a holiday party.

What’s the problem? Some family members don’t want to come to a family gathering if their sibling is going to bring their intentionally unvaccinated child.

And why is that a problem if they are all fully vaccinated (a common argument posed by anti-vaccine folks)?

It should be clear that they are not all fully vaccinated. At least one of the grandchildren is just 6-months-old, so is too young to be fully vaccinated. She will not get her first dose of MMR and chicken pox vaccine, for example, until she is at least 12 months old.

But she isn’t the only one at risk. The other children and adults could be at risk because no vaccine is 100% effective. Vaccines work and they work very well. They just aren’t perfect.

What Ask Amy Gets Right and Wrong

Ask Amy was smart to turn to a pediatrician for help on this question.

And Dr. Thoele is right, this intentionally unvaccinated child is getting away with hiding in herd (at least so far) and won’t get anyone else sick unless he is exposed first and gets sick himself.

“If you choose to delay some vaccines or reject some vaccines entirely, there can be risks. Please follow these steps to protect your child, your family, and others.”

CDC on If You Choose Not to Vaccinate Your Child, Understand the Risk and Responsibilities

Many of us would take exception to the part that it is “highly unlikely” that this child could get a vaccine-preventable disease though. There are usually one or more outbreaks of chicken pox, mumps, pertussis, and measles, etc., going on in different parts of the United States throughout the year. And because parents who don’t vaccinate their children often cluster together in groups, it increases the chances that their kids will catch something.

Have they traveled out of the country? Have they been exposed to someone who has? That increases their risk too.

And what about the flu?

“(Dr) Thoele and I both hope that everyone attends the family get-together and that all family members should try their best to be nice to one another. There is, fortunately, no vaccine preventing that.”

There is also nothing preventing those parents from vaccinating their child.

Unvaccinated Kids at a Holiday Party

So should this intentionally unvaccinated toddler come to the holiday party?

Should other kids come if the unvaccinated child will be there?

While no one wants a family to be split over such a matter or for grandparents to be put in the middle, it is a much more complicated issue than wishing that everyone play nice.

Not Vaccinated? No Kisses!
A billboard advocating that teens and adults get a Tdap booster.

Not surprisingly, pediatricians get asked about these kinds of situation all of the time:

  • Should new parents allow family members to visit if they won’t get a flu shot?
  • When can they allow a family member to see their new baby if they won’t get a Tdap booster?
  • What do they do about the family members who don’t get vaccinated and don’t even take their kids to the doctor for regular checkups?

And what’s the answer?

Understand that kids aren’t at least partially protected against:

  • pertussis until after the third dose of DTaP at six months
  • the flu until after getting a first flu shot at six months, keeping in mind that they are actually going to need a second flu shot for full protection, since it is the first time that they are being vaccinated against influenza
  • measles, mumps, and chicken pox until they get their first dose of MMR and the chicken pox vaccine when they are 12 months old

And that’s why many parents would not, if they had a choice, expose their children to an intentionally unvaccinated child until after they had at least had their 12 to 15 month vaccines. By this time, they have also gotten 3-4 doses of Hib and Prevnar, and have completed their rotavirus vaccines.

Of course, if the child, or any of the adults, had an immune system problem, were getting treated for cancer, or had any other condition that would put them at higher risk for getting a vaccine-preventable disease, then they would likely never voluntarily expose themselves to someone who was intentionally unvaccinated.

I say voluntarily, because we often don’t have a choice.

In most states, folks are allowed to send their intentionally unvaccinated kids to school and daycare. And those kids put us all at risk.

And yes, there are vaccines to prevent that.

What to Know About Unvaccinated Kids at a Holiday Party

Many parents would avoid voluntarily exposing their kids to an intentionally unvaccinated child until they have at least completed their primary series of vaccines, when they are 12 to 15 months old.

More on Unvaccinated Kids at a Holiday Party