Tag: Tdap

What Percentage of Adults Are up to Date on Their Immunizations?

Are you up to date on your vaccines?

What about everyone else?

What Percentage of Adults Are up to Date on Their Immunizations?

Can you guess why this question comes up so often?

Yup.

There is no plan to force adults to get vaccinated...
There is no plan to force adults to get vaccinated…

It’s about herd immunity.

If most adults aren’t immune because they haven’t been vaccinated or don’t get boosters, then since we aren’t seeing that many outbreaks, herd immunity itself must be a myth.

The thing is though, adults were either born in the pre-vaccine era and likely earned their natural immunity or were born in the vaccine era and are vaccinated and immune.

It is also important to understand that herd immunity is disease specific, so when we talk about herd immunity for measles, it doesn’t matter if everyone has herd immunity levels of protection against hepatitis A or Hib.

And adults do get a few boosters and some vaccines that are only recommended for adults, including the shingles vaccine.

In addition, some vaccines, like Hib and Prevnar, have indirect effects, protecting adults even though they aren’t vaccinated, because vaccinated kids are less likely to become infectious.

But back to the original question, how many adults are up to date on their immunizations?

“While modest gains occurred in vaccination coverage for pneumococcal, Tdap, hepatitis A (persons with chronic liver conditions), herpes zoster, and HPV vaccination, coverage did not improve for other vaccinations and many adults remained unvaccinated with recommended vaccines. “

Vaccination Coverage Among Adults in the United States, National Health Interview Survey, 2016

While most adults are immune to what were once common childhood diseases, like measles and mumps, because they were either vaccinated or had the disease naturally, many could do better with newer vaccines that weren’t available when they were kids.

More on Adult Vaccination Statistics

Making a Better Pertussis Vaccine

So we know that we need a better pertussis vaccine.

DTaP and Tdap just aren’t doing the job that they should be doing.

Whooping Cough is back, again.
Whooping Cough is back, again.

So when will we get one?

Making a Better Pertussis Vaccine

Since anti-vaccine folks are always talking about the 300 new vaccines in the pipeline, you would think that we would have had several new pertussis vaccines by now…

Unfortunately, we don’t.

What we do have is some good candidates, including:

  • new acellular pertussis vaccines, either with more antigens or an adjuvant
  • a new live attenuated nasal vaccine, BPZE1
  • new whole-cell vaccines with reduced endotoxin contents (so should have fewer side effects that then original whole-cell pertussis vaccine – DTP)

Before you get too excited, keep in mind that none of these vaccines will be available in your pediatrician’s office any time soon. Developing a new vaccine takes a lot of time.

BPZE1 has started phase 2a trials though.

What do we do until we get new pertussis vaccines?

“We should be more vigilant than we have been in the past to recognize and treat pertussis in all age groups so that transmission to young infants is reduced. Most important (although not discussed in this review) is to ensure that all pregnant women receive the Tdap vaccine between 27 and 36 weeks’ gestation with each pregnancy. Also, we should consider routinely administering Tdap vaccine every 3 years to all adolescents and adults who were primed with a DTaP vaccine.”

James D. Cherry on The 112-Year Odyssey of Pertussis and Pertussis Vaccines—Mistakes Made and Implications for the Future

We should keep using the pertussis vaccines we have!

Vaccines work, even when they aren’t as effective as we would like.

More on Making a Better Pertussis Vaccine

When Was the Last Case of Diphtheria?

Believe it or not, measles isn’t the only vaccine-preventable disease that is still around.

While you likely aren’t too surprised about the flu deaths and the cases of meningococcal disease, did you know that kids still get Hib, babies still get hepatitis B, and that there were three cases of human rabies and a case of diphtheria in the United States last year?

When Was the Last Case of Diphtheria?

Yes, diphtheria.

Diphtheria strikes unprotected children.

That’s despite the fact that the diphtheria vaccine has been around for over 100 years, long before it was combined with the first whole cell pertussis vaccine and the tetanus vaccine to form the DPT vaccine.

A vaccine that helped control respiratory diphtheria, which could lead to the formation of a pseudomembrane in a child’s airway, giving diphtheria the nickname of the “strangling angel.”

The last big outbreaks of diphtheria in the United States occurred in the 1970s, although sporadic cases had continued since, albeit at lower and lower levels each year. Eventually, endemic respiratory diphtheria was declared eliminated in 2009.

Still, we know that there have been some recent cases of diphtheria in the United States.

In April of 2014, a teen from Montgomery County, Ohio developed diphtheria.

And again in April of 2018, someone in Oklahoma developed diphtheria.

Why do we care about a few isolated cases?

Because we know how quickly diphtheria can come back if we stop vaccinating our kids!

Just look at what is happening in many other countries that once had these diseases under good control:

  • a 22-year-old unvaccinated women who died in Australia (2011)
  • an unvaccinated 3-year-old who died in Belgium (2016)
  • a family that became infected in South Africa in which at least one child died (August 2017)
  • at least 7 cases of diphtheria in Ukraine (2018)
  • an unvaccinated man in Australia who died (2018)
  • a case in Canada (2018)
  • 8 cases and 3 deaths in Columbia (2018)

Not to mention the large number of diphtheria deaths in Yemen, Venezuela, Haiti, and among Rohingya refugees.

Let’s not bring these diseases back. Vaccines are safe, with few risks, and obviously necessary.

More on the Last Case of Diphtheria

Are the Tdap and DTaP Vaccines the Same Thing?

You have probably already figured out the Tdap and DTaP aren’t the same vaccine, after all, if they were, why would they have different names, right?

Are the Tdap and DTaP Vaccines the Same Thing?

I bet you don’t know the difference between the two vaccines though.

Yes, they both are both combination vaccines that protect against diphtheria, tetanus, and pertussis.

The difference is that one (DTaP) is used as the primary series for infants and younger children (age 6 years and under) and the other (Tdap) is given to older children (age 7 years and above), teens, and adults.

Okay, that’s not the only difference.

The DTaP vaccine actually contains more diphtheria and pertussis antigens than Tdap, which is why it has the capital “D” and “P” in its name. The amount of tetanus toxoid antigens are about the same in both vaccines.

So Tdap contains the same amount of tetanus toxoid, plus a reduced amount of diphtheria and acellular pertussis antigens, as compared to DTaP.

While you would think that older children and adults would get the vaccine with the higher amount of antigens, since they are bigger, that’s not how this works. Vaccines typically start working at the injection site, so body size isn’t a key factor in determining the amount of ingredients.

As a booster dose of vaccine, the lower amount of antigens works just fine and helps reduce the risk of side effects from repeated doses that you might get with higher antigen counts.

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