Tag: epidemic

Understanding Flu Season

Flu season starts.

A lot of folks get sick as flu season peaks.

Flu season eventually ends.

What’s to understand?

Understanding Flu Season

While we see flu activity at epidemic levels every year, some years are clearly much worse than others.

What kind of flu season will we have this year?
What kind of flu season will we have this year?

And while the severity of a flu season is easy to see after it is over, many of us could use a little help making sense of things when we are still in the middle of it.

  • Geographic Spread of Influenza Viruses – when you hear that there is widespread flu activity in a lot of states, this is what they are talking about. The only problem is that this doesn’t really tell you anything about the severity of a flu season. We get widespread flu activity in all states, or almost all states, each and every year as flu season peaks.
  • ILI Activity Indicator Map – like the maps showing the geographic spread of the flu, the ILI activity indicator map can help you tell where flu is spreading, but since it doesn’t necessarily represent the whole state, it can be misleading.
  • Influenza-like Illness Surveillance – the proportion of outpatient visits for influenza-like illness (ILI), or basically, how many people are going to the doctor with flu symptoms. Once we get above the national baseline of 2.2%, we know that flu season is starting in an area. How high can ILI get? Recently, it has peaked between 3.6% (2015-2016) and 7.5% (2017-2018). But that’s nationally. Because of wide variability in regional level data, you might see much higher ILI numbers in your state. For example, the regional baseline in Texas is 4%, while it is just 1.1% in Idaho. Still, widespread flu activity with a high ILI likely means a bad flu season.
  • Flu-Associated Hospitalizations – laboratory-confirmed influenza-associated hospitalizations. Overall, as flu season peaks, this can range from 4 to 5 per 100,000 population in a typical flu season, to 9 or 10 in a more severe flu season. This is also reported by age group. During a bad flu season, flu-associated hospitalizations will be high.
  • Mortality Surveillance – the proportion of deaths attributed to pneumonia and influenza. At some point in flu season, we get above an epidemic threshold and more people die with the flu, especially during a bad flu season.
  • Pediatric Deaths – pediatric influenza-associated deaths have been a nationally notifiable condition since the 2004 flu season and since then, on average, about 118 kids die with the flu each year. Last season was especially bad, with 185 pediatric flu deaths.

So how do you really know if it is a bad flu season?

Look for a high ILI%, high flu-associated hospitalizations, which will almost certainly be followed by a high mortality surveillance.

You also want to check viral surveillance data. Are the majority of influenza viruses being tested antigenically and genetically similar to the cell-grown reference viruses representing the 2018–2019 Northern Hemisphere influenza vaccine viruses? If not, that could mean a vaccine strain mismatch and a worse flu season.

And don’t be surprised by reports of widespread flu activity or rising ILI. That’s just flu season.

More on Understanding Flu Season

Flu Season Predictions

No, I can’t see into the future…

I predict that I will continue to get a flu shot each year, at least until they come out with a universal flu vaccine.
I predict that I will continue to get a flu shot each year, at least until they come out with a universal flu vaccine.

But some things are very easy to predict.

Flu Season Predictions

Here are some predictions for this year’s flu season.

  1. We will have a flu season epidemic in the United States this year. Surprised by that prediction? Don’t be. Flu activity reaches epidemic levels each and every year. What we don’t always have are flu pandemics, during which flu activity is very high in multiple parts of the world. By definition, flu season is an epidemic.
  2. Almost all states will eventually report having widespread influenza activity as flu season peaks. Again, this is not a bold prediction. It happens every year. How severe is flu season going to be? No one can really predict that, but we can look at the proportion of people seeing their health care provider for influenza-like illness (ILI) and laboratory-confirmed influenza-associated hospitalization rates as flu season moves along to get some idea. Remember, measures of the geographic spread of the flu don’t really tell you anything about the severity of flu activity.
  3. Dozens of kids will die with the flu – most of them unvaccinated. Remember, 37 kids died in the mildest flu season we had.
  4. A little under half of adults will get a flu vaccine, even though the current recommendation is that everyone who is at least six months old without a true contraindication get vaccinated each year.
  5. A little over half of parents will get their kids a flu vaccine.
  6. Some people who get a flu vaccine will still get the flu. You know the flu vaccine isn’t the most effective, but it still has plenty of other benefits, so even if you did still get the flu, hopefully you got a milder case, weren’t hospitalized, and didn’t die.
  7. Some people who get a flu vaccine and get the flu will blame their flu shot, even though it is well known that the flu shot can’t give you the flu.
  8. Many people who aren’t high risk will be prescribed Tamiflu. Or Xofluza, because it is new.
  9. Tens of thousands of adults will die with the flu. Even in a mild flu season, the flu is very deadly.
  10. Some folks will continue to push the idea that there is a vaginal spermicide in flu shots, even though that anti-vaccine talking point has been refuted a thousand times already.

What else can you predict about flu season?

Some folks will think it is too late to get a flu shot.

It isn’t.

Get your flu shot if you haven’t and get protected for the rest of flu season.

Another bold prediction? Elderberry syrup and Oscillococcinum are not going to help prevent or treat your flu symptoms.

More Flu Season Predictions

Which Vaccines Do You Get When You Join the Military?

The oral adenovirus vaccine is approved to prevent adenovirus infections in military populations.

Believe it or not, many vaccines are available that we don’t routinely get.

Some we only get if we travel, like vaccines for yellow fever and typhoid. Others we only get in high risk situations, like if you get exposed to a bat with rabies.

And one, the adenovirus vaccine, you can only get if you join the military.

Which Vaccines Do You Get When You Join the Military?

But don’t folks get a lot of vaccines when they join the military?

It depends…

Whether you join the Army, Navy, Air Force, Marine Corps, or Coast Guard, health personnel will evaluate your immunity status by checking your titers to routine vaccine-preventable diseases. So no, if you were wondering, it doesn’t seem like they just check the vaccine records that you might bring from your pediatrician.

And then once they assess your immunization or immunity status, you will get vaccinated:

  • upon accession – adenovirus, influenza, meningococcal, MMR, Tdap, and chicken pox
  • during the first or second half of collective training – hep A, hep B, and polio (if needed, although a dose of IPV after age 18 is required) and other vaccines based on risk

So, in addition to getting caught up on all routine vaccines that they might be missing, there are other “military vaccines” that they might need, including:

  • Adenovirus vaccine – given to enlisted soldiers during basic training
  • Anthrax vaccine – only military personnel with extra risk, although some civilians can get this vaccine too
  • Smallpox vaccine – only military personnel who are high risk and smallpox epidemic response team members, although some civilians can get this vaccine too

Which vaccines you get in the military might be determined by where you are getting deployed to.
Which vaccines you get in the military will likely be determined by where you get deployed.

Like the recommendations for civilians, other vaccines are mainly given to military personal if they have extra risk based on where they are being deployed.

  • Cholera – only military personnel with extra risk based on deployment or travel to endemic areas
  • Japanese encephalitis – only military personnel with extra risk based on deployment or travel to endemic area in Eastern Asia and certain western Pacific Islands
  • Rabies vaccine – pre-exposure vaccination is only for military personnel with animal control duties or with extra risk based on deployment, including special operations personnel
  • Typhoid vaccine – only military personnel with extra risk based on deployment or travel to typhoid-endemic areas and other areas with poor sanitation.
  • Yellow fever vaccine – only military personnel with extra risk based on deployment or travel to yellow-fever-endemic areas in sub-Saharan Africa and tropical South America.

These are the same vaccines that we would get if we traveled to high risk areas.

Military Vaccines in Development

It shouldn’t be a surprise that the military does research on infectious diseases and vaccines.

Members of the military are often put at great risk for known and emerging diseases, like Ebola, Zika, and malaria.

That’s why some vaccines might have been given as an investigational new drug in special situations, typically when “individuals who have a high occupational risk – laboratory workers, facilities inspectors, vaccine manufacturers and certain military response teams.”

These vaccines, which were initially developed at US Army labs, are no longer being produced, but have included:

  • Argentine hemorrhagic fever (Junin virus) vaccine
  • Chikungunya fever vaccine
  • Eastern equine encephalitis vaccine
  • Q fever vaccine
  • Rift Valley fever vaccine
  • Tularemia vaccine
  • Venezuelan equine encephalitis vaccine
  • Western equine encephalitis vaccine

Today, the Walter Reed Army Institute of Research (WRAIR) “is a leader in global efforts against the world’s most pervasive and high impact infectious diseases.”

WRAIR is working on vaccines for HIV, Ebola, MERS, and Zika.

What to Know About Military Vaccines

You will need some extra vaccines when you enlist in the military, but how many will depend on if you are up-to-date when you join and your area of responsibility. So there is no one-size-fits-all military immunization schedule.

More on Military Vaccines