Category: Vaccine Preventable Diseases

When is Measles Season?

For a while, especially once we eliminated the endemic spread of measles, we weren’t thinking about measles seasons anymore.

In addition to the recent rise in measles cases, this slide shows the patterns of measles seasons in different parts of the world.
In addition to the recent rise in measles cases, this slide shows the patterns of measles seasons in different parts of the world.

Unfortunately, with ongoing outbreaks and rising cases, many people are asking again – just when is measles season?

When is Measles Season?

Traditionally, the time when measles case counts are the highest occurs:

  • during the late winter and early spring (temperate climates, like the United States)
  • after the rainy season (tropical climates)
  • when kids are in school

So just like flu season, it’s always measles season somewhere…

And in areas of the world where measles is still highly endemic, you can expect cycles of larger measles epidemics every 1 to 4 years.

Can you guess why?

“As higher uniform population immunity is achieved the scale of epidemics, both their duration and absolute number of cases, progressively decreases. Epidemic frequency simultaneously decreases with increasing time intervals between epidemics. Another uniform feature as elimination is approached is the loss of epidemic seasonality.”

Durrheim et al on Measles – The epidemiology of elimination

I’ll give you a hint – there is nothing different about the measles virus during those years.

Eventually though, as the number of people susceptible to measles builds up, there is the opportunity for bigger outbreaks. Of course, that doesn’t happen if most people are vaccinated and protected.

When is Measles Season in the United States?

What about in the United States in the post-vaccine era?

Visiting a place with a lot of measles, especially if you aren't vaccinated and protected, increases the risk that you will bring measles home with you and start an outbreak.
Visiting a place with a lot of measles, especially if you aren’t vaccinated and protected, increases the risk that you will bring measles home with you and start an outbreak.

We don’t really have a measles season, as all of our cases are now imported from other parts of the world.

  1. Where and when are folks traveling?
  2. Where is measles on the rise?

That’s when we will see more measles cases here.

“Source countries included Philippines (14 cases), Ukraine (8), Israel (5), Thailand (3), Vietnam (2), Germany (2), and one importation each from Algeria, France, India, Lithuania, Russia, and the United Kingdom.”

Increase in Measles Cases — United States, January 1–April 26, 2019

In the early part of 2019, we saw a lot of cases because unvaccinated travelers were returning from Philippines, Ukraine, and Israel, countries in peak measles season.

Are Europe's measles outbreaks slowing down yet?
Are Europe’s measles outbreaks slowing down yet?

As cases in those countries hopefully slow down over the summer, unfortunately, we might see a rise in other parts of the world.

Of course, there is an easy way to end our measles seasons once and for all.

Two doses of MMR is your best protection against measles.

Get vaccinated and protected, especially before traveling out of the country.

More on Measles Season?

An Unvaccinated Girl in Italy Has Tetanus

Remember the story of the unvaccinated boy in Oregon who recently had tetanus?

He spent nearly two months in the hospital, nearly all of it in the ICU, and his care cost just over $800,000. All for a disease that is easily vaccine-preventable.

An Unvaccinated Girl in Italy Has Tetanus

That boy in Oregon wasn’t the first intentionally unvaccinated kid to have tetanus recently and tragically, he won’t be the last.

An Unvaccinated Girl in Italy Has Tetanus
The girl fell and skinned her knee. Unvaccinated, she ended up in the ICU with tetanus.

The latest case is an unvaccinated girl in Verona, Italy.

An Unvaccinated Girl in Italy Has Tetanus

The girl, from Povegliano, is intubated and sedated and in critical condition.

Her family is being investigated to see why she wasn’t vaccinated.

Unbelievably, she joins a growing list of kids who have gotten tetanus for no good reason in the post-vaccination era.

  • an unvaccinated 4-year-old who developed tetanus after a toenail injury. He was intubated for over two weeks.
  • an unvaccinated 10-year-old in Sardinia, Italy who cut his forehead after crashing his bike
  • an unvaccinated 7-year-old in New Zealand who had a small cut his foot
  • an unvaccinated 7-year-old in Australia who cut her foot while playing in the garden

Wondering why it doesn’t happen more often?

Most kids are vaccinated and protected!

And most parents, even those who are scared to vaccinate their kids, understand that tetanus is basically everywhere and almost impossible to avoid.

More on Unvaccinated Kids with Tetanus

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