Tag: waning immunity

Does Measles Protection from the MMR Vaccine Wane Over Time?

Why do some parents think that measles protection from the MMR vaccine might wane over time?

Yup – misinformation from the usual suspects.

Does Measles Protection from the MMR Vaccine Wane Over Time?

Wait, how can this be misinformation if they are citing a source and it is a study published by the CDC?

“The results, published in Archives of Pediatrics and Adolescent Medicine, show that even after being previously vaccinated twice for measles, about 35% of vaccinated 7-year-olds and 60% of vaccinated 15-year-olds are susceptible to subclinical infection with measles virus.”

Physicians for Informed Consent: CDC Data Shows Immunity from the MMR Vaccine Wanes Over Time

While that doesn’t sound good, that’s not what the study really says!

“A rise in the proportion of persons with low antibody levels suggests an increase in potential susceptibility, but low titers are unlikely to represent the same risk of illness or viral transmission as absent antibodies.”

LeBaron et al on Persistence of Measles Antibodies After 2 Doses of Measles Vaccine in a Postelimination Environment

They are clearly misinterpreting what the study does say and mean.

“In summary, we found that, in a population of children who had received 2 doses of measles vaccine at ages and intervals consistent with US policy and who were unlikely to have been exposed to wild-type measles, potential susceptibility rates were low for as long as 10 years after the second dose.”

LeBaron et al on Persistence of Measles Antibodies After 2 Doses of Measles Vaccine in a Postelimination Environment

The funny thing is that the study is about what happens to vaccine induced immunity in the absence of exogenous boosting.

In other words, what happens when vaccines get diseases under good control so that we are no longer exposed to wild disease which can give our antibody levels a little boost.

So they are highlighting a study that proves that vaccines work and fortunately, it concludes that “measles antibody persists,” even without exogenous boosting.

The other study they cite discusses a measles outbreak in Japan.

In the 2018 outbreak, 99 people got measles.

“A recent outbreak of measles in Okinawa Prefecture, Japan ended with 33 measles cases whose symptoms were masked because of insufficient protection against the disease (modified measles).”

Mizumoto et al on Transmission potential of modified measles during an outbreak, Japan, March‒May 2018

Only 10 were fully vaccinated with two doses of measles vaccine. An additional 20 had one dose.

“Symptoms in modified measles cases are masked, so they do not present with the full (typical) symptoms of measles (fever, maculo-papular rash and catarrhal symptoms such as cough, coryza or conjunctivitis) and their transmission risk is reported to be lower.”

Mizumoto et al on Transmission potential of modified measles during an outbreak, Japan, March‒May 2018

While many vaccines do lead to milder disease, even if the vaccine doesn’t provide full protection, we don’t typically see that with measles, except for rare case reports.

So instead of modified measles, it is possible that many of these folks were simply very recently vaccinated, likely in response to the outbreak, and were having a vaccine reaction.

Remember, measles containing vaccines do commonly cause a fever and rash as a side effect. That’s why we sometimes see vaccine strain measles in outbreak reports. These aren’t typically people with measles or modified measles.

“This case report adds further evidence for lower infectivity of modified measles with no secondary cases and highlights the potential requirement for updated contact tracing recommendations in this scenario. Other case reports have shown that individuals with modified measles and history of prior vaccination have more robust levels of plaque reduction neutralisation (PRN) titre, reflecting an immunity booster response. These case studies also identified no secondary cases. In measles outbreak reports in healthcare workers with two documented MMR vaccines, no onward transmission of measles has been reported.”

Uren et al on Modified measles with an atypical presentation

Still, although it would be better if vaccines prevented disease and you would get sick at all, when they don’t, isn’t a modified case better than getting full blown measles?

And the bottom line is that the so-called Physicians for Informed Consent is once again misleading people if they are trying to make them think that the MMR vaccine will wane and that “Nearly 50% of Vaccinated U.S. Schoolchildren Can Become Infected With and Spread Measles.”

The only school where you will find that nearly 50% of the kids are susceptible to measles is likely a Waldorf school. But that’s only because they won’t be vaccinated and protected.

More on Waning Immunity

Are Reported Pertussis Cases up by 114% Since 1967?

We know that we are seeing more pertussis cases these days.

Although the last few years have been better, 2012 was an especially bad year, with at least 48,277 cases and tragically, at least 4 deaths.

Are Reported Pertussis Cases up by 114% Since 1967?

How does that compare to the the pre-vaccine era?

Cases are still well below what they were in the pre-vaccine era, before we were routinely using DPT and DTaP vaccines.

Reported cases of pertussis are still down from the prevaccine era and there are far fewer deaths, from 37 deaths in 1967 to 6 in 2015.
Reported cases of pertussis are still down from the prevaccine era and there are far fewer deaths, from 37 deaths in 1967 to 6 in 2015.

What about the idea that pertussis cases are up 114% since 1967?

While that may be true, the first thing you should ask yourself when looking at Lauren Novelli’s little graph, is why did she choose 1967?

Reported Pertussis Cases Are Down Since the Pre-Vaccine Era

We did start using a new vaccine in 1967, but it was the measles vaccine, not the DPT vaccine. Vaccines against diphtheria, pertussis, and tetanus had been available for some time and were used more routinely beginning in the 1950s.

And that explains the drop in pertussis cases from just over 120,000 in 1950 to about 40,000 in 1959.

More importantly, even as pertussis cases are increasing again, we aren’t seeing as many people dying from pertussis.

In 2018, there were 13,439 reported pertussis cases and 10 deaths.
In 2018, there were 13,439 reported pertussis cases and 10 deaths.

Is that because of better hygiene, sanitation, and nutrition?

No.

We had those in most of the United States in the 1950s and 60s. The big change is that even though the current pertussis vaccine might not be perfect, having issues with waning immunity, it can still protect you from severe disease.

Vaccinating against pertussis is far from useless and there is absolutely no evidence of dormant bacteria carriers being triggered into becoming active infections.

This is pure propaganda, but you should expect no less from someone who describes themselves as an intuitive nurse and sells CBD oil.

More on Reported Pertussis Cases

Do Vaccinated Kids Who Get Sick Have Milder Disease?

There is another benefit of vaccines that you might not be aware of.

Vaccines are typically very effective, but of course, they aren’t perfect.

Fortunately, even when they don’t work and you do get sick, vaccinated kids will often have milder disease than those who are unvaccinated.

Do Vaccinated Kids Who Get Sick Have Milder Disease?

While no one expects to get a vaccine-preventable disease if they have been vaccinated, it is nice to know that often, you will at least have a milder disease.

“Disease may occur in previously vaccinated individuals. Such breakthroughs are either primary – due to vaccine failure – or secondary. In such cases, the disease is usually milder than in the non-vaccinated.”

Vaccination greatly reduces disease, disability, death and inequity worldwide

Milder mumps and pertussis?

“The number of previous vaccine doses was inversely associated with clinical severity.”

Zamir et al on Characteristics of a large mumps outbreak: Clinical severity, complications and association with vaccination status of mumps outbreak cases

Yes!

And that’s good news for all of the folks concerned about waning immunity with these vaccines.

“A protective effect of vaccination was noted when mean duration of symptoms and hospital stay are analysed, comparing unvaccinated, partially vaccinated and fully vaccinated children. We showed a vaccination dose effect trend, with fully vaccinated children having less-severe RVGE than not vaccinated and partially vaccinated children.”

Justino et al on Clinical Severity and Rotavirus Vaccination among Children Hospitalized for Acute Gastroenteritis in Belém, Northern Brazil

Consider that, in addition to preventing disease:

  • two doses of MMR has been found to have a significant preventive effect against mumps complications, including orchitis, meningitis, and encephalitis, and hospitalization for mumps
  • two doses of the chickenpox vaccine has been found to be very effective at preventing severe disease, in fact, kids with breakthrough chickenpox often don’t have fever, have fewer than 50 spots, and they go away quicker than kids who are unvaccinated.
  • vaccinated kids who get pertussis typically don’t cough as long as those who are unvaccinated
  • the rotavirus vaccine series, in addition to protecting most kids from getting rotavirus infections in the first place, protected all of the vaccinated kids from getting severe infections
  • the flu vaccine reduces the risk of severe disease, especially if you are hospitalized with the flu

What does this all mean?

Two kids with smallpox - one vaccinated and one unvaccinated. Can you guess which is which? The vaccinated child on the right only has one or two spots...
Two kids with smallpox – one vaccinated and one unvaccinated. Can you guess which is which? The vaccinated child on the right only has one or two spots…

It means that vaccines work, even when they don’t work as well as we would like them to!

More On the Severity of Breakthrough Infections

How Do You Know If You Have Measles Immunity?

With all of the measles cases, you might be wondering if you have immunity to measles?

Are you worried that you might get measles?

Should you get a booster dose of MMR?

Or a titer test?

How Do You Know If You Have Measles Immunity?

Fortunately, most of us can feel confident that we do have measles immunity and that we won’t get caught up in any of the ongoing outbreaks.

Why?

If you have had two doses of MMR, then you can be confident that you have measles immunity.
If you have had two doses of MMR, then you can be confident that you have measles immunity.

Because we are vaccinated and protected!

If you haven’t had two doses of MMR (or any measles containing vaccine since 1967), then understand that two doses is your best protection against measles.

Is There a Blood Test for Measles Immunity?

What about titer tests?

While there is a blood or titer test for measles immunity, it isn’t routinely used.

The one situation in which a measles titer test might be useful though, is for those born before 1957 to confirm that they really had measles.

For others considering a titer test in place of vaccination, it is typically better to just get another dose of MMR, but only if you haven’t already had two doses.

Why Was My Measles Titer Negative?

A positive measles titer does mean that you are immune, but what about a negative measles titer?

“For HCP who have 2 documented doses of MMR vaccine or other acceptable evidence of immunity to measles, serologic testing for immunity is not recommended. In the event that a HCP who has 2 documented doses of MMR vaccine is tested serologically and determined to have negative or equivocal measles titer results, it is not recommended that the person receive an additional dose of MMR vaccine. Such persons should be considered to have presumptive evidence of measles immunity. Documented age-appropriate vaccination supersedes the results of subsequent serologic testing.”

Immunization of Health-Care Personnel: Recommendations of the Advisory Committee on Immunization Practices (ACIP)

If you have had two doses of MMR and have a negative measles titer, you don’t need another dose of MMR. You are likely immune, even with that negative titer.

“Most vaccinated persons who appear to lose antibody show an anamnestic immune response upon revaccination, indicating that they are probably still immune.”

Epidemiology and Prevention of Vaccine-Preventable Diseases

And since you would need a second dose if you had a negative titer after having just one shot, you might as well just get the second dose instead of checking your titer.

Do You Need a Measles Booster?

Have you had two doses of MMR?

If so, then you don’t need another dose.

The second dose isn’t technically a booster anyway. It is just for those who might not have responded to their first dose.

And two doses of MMR are about 97% effective at preventing measles.

That’s why most of the people in measles outbreaks are unvaccianted.

Neither primary nor secondary (waning immunity) vaccine failure are common with the measles vaccine.

What’s the biggest issue with the MMR? Folks who are still too scared to get their kids vaccinated and protected!

More on Measles Immunity