Tag: elimination

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?

How Many People Have Died from Measles in 2019?

As measles cases climb, some folks are interested in just one thing, how many people have died from measles this year?

A lot of people are dying from measles this year.
A lot of people are dying from measles this year.

The rest of us?

We understand that as we see more and more cases, it simply increases the chances that someone might eventually die.

How Many People Have Died from Measles in 2019?

So far, we have been very lucky that there have been no measles deaths, even as we are well past 1,000 cases.

Not that 1,000 cases is some magic number where you start to see deaths.

Consider that we only had 188 cases in 2015, when we had the last measles death in the United States. That year, a woman got caught up in a small outbreak in Washington.

Where Are People Dying of Measles in 2019?

There are also many countries with rather small numbers of cases that are seeing measles deaths.

In Samoa, a country that stopped vaccinating last year after two infants tragically died when they got a powerful anesthetic instead of the diluent for the MMR vaccine, four people have died already. Four deaths among about 314 cases, including a 14-month-old, 12-month-old, and an 8-month-old.

And don’t forget that the last death in France, in April 2019, occurred after only 852 cases were reported.

In Romania, the first death of 2019, in January, came after just 133 cases.

Measles acts quickly. Do your part to protect yourself and others.

And since the outbreaks in Europe started in 2016, there have been deaths in:

  • Bulgaria – only 416 cases
  • Portugal – only 202 cases
  • Spain – only 457 cases
  • Switzerland – two deaths and only 197 cases!
  • Hungary – only 24 cases!

Of course, there are more deaths in countries that are seeing more cases.

Again, since 2016:

CountryDeathsCases
Romania6418,502
Greece43,270
Italy139,277
France44,138
UK12,000
Germany35,000 (since 2015)
Israel34,292 (since 2018)
Ukraine41115,000 (2017)
Serbia155,797 (since Oct 2017)
Brazil1219,036 (since 2018)
Tunisia303,141 (2019)
Malaysia62,129 (since 2017)
Thailand235,893 (since 2018)
Guinea141,359 cases (2019)
Liberia51,357 cases (2019)
Uganda51,584 cases (2019)
Samoa4314 (2019)

And a lot more deaths in some countries:

  • Madagascarat least 1,233 reported deaths among over 150,000 registered cases
  • Philippines – at least 676 deaths since 2018, with over 55,000 cases.
  • Venezuela – at least 134 deaths since 2017, with over 9,585 cases
  • Democratic Republic of Congo – over 4,000 deaths this year, with over 200,000 cases
  • Nigeria – at least 275 deaths this year, with over 54,000 cases
  • Chadat least 241 deaths this year, with over 24,000 cases
  • South Sudan – 91 deaths among 2,472 cases since November 2018
  • Niger – 53 deaths among 9,741 cases in 2019
  • Angola – at least 64 deaths this year, with over 3,000 cases

Measles is on the rise.

Measles is on the rise in many parts of the world and so are measles deaths.
Measles is on the rise in many parts of the world and so are measles deaths.

Measles deaths are on the rise too. While the risk of complications of measles can be reduced with vitamin A treatment, that doesn’t eliminate them. And the benefit is mostly in those who are already vitamin A deficient. Vitamin A has a much more modest effect in developed countries, where measles deaths still occur.

What to reduce your child’s risk of dying from measles?

Get them vaccinated and protected.

Tragically, this all comes after we were making progress towards measles elimination, reaching a record low for global cases and deaths just a few years ago.

How will we respond? An even stronger effort to finally get measles under control? Or continued worsening, with more cases and more deaths?

More on Measles Deaths in 2019

Is Measles Still Eliminated in the United States?

Do you remember when measles was eliminated in the United States?

You probably should.

Remember when we eliminated measles and we used to only have about 100 cases of measles in the United States each year?
Remember when we eliminated measles and we used to only have about 100 cases of measles in the United States each year? Pensacola News Journal July 2000

It wasn’t that long ago…

When Measles Was Eliminated in the United States

After several years of declining numbers of measles outbreaks in the United States, the endemic spread of measles was declared eliminated in March 2000.

“The data indicated that, during 1997–1999, measles incidence has remained low (<0.5 cases per 1,000,000 population) and that most states and 99% of counties reported no measles cases. In addition, measles surveillance was sensitive enough to consistently detect imported cases, isolated cases, and small outbreaks. Evidence of high population immunity included coverage of >90% with the first dose of measles vaccine in children aged 19–35 months since 1996 and 98% coverage among children entering school. In 48 states and the District of Columbia, a second dose of measles vaccine is required for school entry. A national serosurvey indicated that 93% of persons aged >6 years have antibody to measles.”

Measles — United States, 1999

What did that mean?

It is easy to understand when you note that we still had 86 cases of measles in the United States that year.

So, measles wasn’t gone yet. It was just that most cases were imported from outside the country. Only imported strains of the measles virus were causing outbreaks.

“The end of endemic measles transmission in the United States has both domestic and international importance. Domestically, the absence of endemic exposure to measles means few persons in the United States will be infected and risk complications of measles. This decreased risk of exposure provides protection to groups not protected directly by vaccination: children too young for routine vaccination; the few persons who, although vaccinated, are not protected, primarily from failure to mount an adequate response to vaccine; persons for whom vaccine is contraindicated (e.g., those with immunodeficiency); and persons who choose not to be vaccinated.”

Wharton on Measles Elimination in the United States

Unfortunately, the “choose not to be vaccinated” group might be endagering our claim to have eliminated measles.

Is Measles Still Eliminated in the United States?

As we break more and more measles records this year, it would be easy to just say that the endemic spread of measles is no longer eliminated in the United States.

“Endemic measles transmission is the existence of any continuous indigenous chain of transmission of measles virus that persists for >1 year in any defined geographic area (e.g., the United States).”

Orenstein on Defining and Assessing Measles Elimination Goals

Still, when you look at the numbers, technically, measles isn’t yet spreading endemically in the United States.

Although we are seeing measles cases in 27 states, about 70% of them are in just two outbreaks in one state - New York.
Although we are seeing measles cases in 27 states, about 70% of them are in just two outbreaks in one state – New York.

We are getting close though.

The outbreaks in Rockland County and Brooklyn started in September and October 2018. If they aren’t stopped soon, will it be easier to make a case that measles is no longer eliminated in the United States?

“Outbreaks in New York City and Rockland County, New York have continued for nearly 8 months. If these outbreaks continue through summer and fall, the United States may lose its measles elimination status.”

U.S. measles cases in first five months of 2019 surpass total cases per year for past 25 years

It sounds like it.

One thing to consider though, after an unvaccinated visitor introduced measles to Brooklyn from Israel back in October, measles has been reintroduced into the community at least seven other times! This includes travelers from Israel, UK, and Ukraine.

So the outbreak isn’t necessarily a “continuous indigenous chain of transmission of measles virus.”

It is multiple chains in the same community.

“There have been additional cases of measles from international travelers to Rockland, exposing more people to measles.”

2018 – 2019 Measles Outbreak in Rockland County

The same thing has happened in Rockland County after the initial importation from Israel in September.

Measles Elimination Criteria

Does that matter?

It likely should, but let’s also look at how we do with other criteria that are often used to assess the absence of the endemic spread of measles:

  • Few measles cases/low measles incidence – we will have the most cases in 2019 since 1992, but most cases are clustered in just a few big outbreaks
  • The duration of outbreaks is short – outbreaks are getting longer and harder to contain, but part of the problem is the global rise in measles and the reintroduction of measles into existing outbreaks
  • Most cases are associated with international importation – still very true
  • No endemic measles virus strain – outbreaks this year have been associated with strains that are commonly seen in Ukraine, the Philippines, and a few other areas
  • Long periods with no unknown-source cases – most cases are linked to international travel
  • High population immunity – except for pockets of susceptibles, folks who intentionally don’t vaccinate their kids or get themselves vaccinated, we do have high population immunity
  • Low levels of transmission from reported cases – in most outbreaks, that it is still true, unfortunately, there are more outbreaks this year
  • Adequate measles surveillance system – definitely true

What is the best argument that the endemic spread of measles has still been eliminated in the United States?

“A small number of cases have occurred outside of these neighborhoods but have, to date, not resulted in sustained transmission of measles.”

Measles Cases Rise to 466 Including in Two Unvaccinated Children Spending Time in Areas with Measles Activity

Even where there are big outbreaks, measles isn’t spreading outside of very specific communities of intentionally unvaccinated children and adults.

And that’s because most people are vaccinated and protected and aren’t letting measles spread endemically!

Losing Measles Elimination Status

If we did lose our status of having eliminated measles, we wouldn’t be the first.

“As of 30 June 2018, measles transmission in Venezuela has been ongoing for over one year. Therefore, endemic transmission of measles is considered to have been reestablished in Venezuela.”

Fourth ad hoc Meeting of the Technical Advisory Group (TAG) on Vaccine-preventable Diseases

Tragically, since their outbreaks began a few years ago, there have been nearly 10,000 cases and at least 78 deaths. Cases have also spread to many other countries in South America.

Venezuela isn’t the only country where we have seen the return of measles though.

In 2017, the European regional verification commission verified the reestablishment of the endemic spread of measles in the Russian Federation and in Germany.

“Countries in all six WHO regions have adopted goals for measles elimination by 2020.”

Progress Toward Regional Measles Elimination — Worldwide, 2000–2017

Surprisingly, some other countries in Europe, like Belgium, France, and Italy, never eliminated measles.

What’s next?

Hopefully, instead of a new normal, the rise in cases gets us back on track to eliminating and one day eradicating measles.

More on When Measles Was Eliminated in the United States

If Measles Was Eliminated, Why Do We Still Have Measles?

Measles has been declared eliminated in the United States.

Unfortunately, that doesn’t mean that we totatly got rid of measles.

When Was Measles Eliminated in the United States?

That becomes clear when you realize that there were 86 cases of measles in the United States when measles was eliminated.

When was that?

Back in March 2000.

What Does Measles Elimination Really Mean?

So why do we still have measles if it was eliminated already?

It’s because elimination is not eradication.

Measles is much more contagious than smallpox, which is part of the reason we are stuck in the measles elimination phase.
Measles is much more contagious than smallpox, which is part of the reason we are stuck in the elimination phase.

And even then, technically measles itself hasn’t been eliminated in the United States.

The Endemic Spread of Measles

Only the endemic spread of measles has been eliminated.

“Endemic measles transmission is the existence of any continuous indigenous chain of transmission of measles virus that persists for >1 year in any defined geographic area (e.g., the United States).”

Orenstein on Defining and Assessing Measles Elimination Goals

That’s why we still have measles. All of the cases we do now have are either imported or linked to a case that was imported.

Unfortunately, as our measles outbreaks get longer and harder to control, it could be that we soon lose our designation of having eliminated measles and all of the progress that went with it.

More on Measles Elimination in the United States