Calling all measles experts...

I don't study measles, but I study other infectious diseases, applying core principles here

There’s a lot of hoopla going around by this tweet from Secretary Kennedy:

This is shocking the medical freedom world, obviously. Let’s talk about what this says, what it doesn’t say, and what else is important to say.

What it says: The vaccine is the most effective way to prevent the spread of measles. So yes, every medical website (CDC, other medical sites, etc) say this. The claim is >90% efficacy (effectiveness? not sure). And there are some sites that show that the effectiveness wanes with time. Here’s the thing - when there is that strong a claim about a vaccine preventing infection/disease, there will never be any additional research about other great preventative efforts. Seriously - if a grant proposal came in for a project to examine other preventative measures and there was already an effective vaccine, that project ain’t getting funded.

What it doesn’t say: It doesn’t say anything about safety. The follow-up tweets are noteworthy:

Now, some of the sites that talk about measles vaccines mention post-exposure prophylaxis, using vaccines. This is where we need to be careful:

1. Are there safety studies, or even efficacy studies, of post-exposure prophylaxis?

2. Does this align with the CDC schedule? This is an important question. Remember, the CDC schedule is based on what the immune response can handle (that’s why things are specific by age, spacing, co-occurence, etc). According to this question, the first shot is given 12-15 months, and the next is given 4-6 years… and then there isn’t another one on the schedule after that. Is it a good idea to exceed the schedule? Has the safety been demonstrated beyond what is shown on this schedule? This is my biggest concern and it is important to point out.

How else to prevent measles? The research needs to be done. There are a lot of lips flapping about vitamin A not being proven… a quick lit search pulled up this meta-analysis that suggests there is at least some promise for vitamin A. I found that study in about 3 minutes… there are surely a bunch more.

Measles is always around. The CDC website has this lovely graph:

I’m willing to bet the number in 2020 is wrong because well we all know that there were no infectious diseases of any kind other than COVID that year (eye roll). And yes of course 2025 isn’t over yet… The CDC’s website futher says that measles was “eliminated” in 2000 “meaning there is no measles spreading within the country and new cases are only found when someone contracts measles abroad and returns to the country.” (CDC’s words) It’s rather interesting that CDC’s website emphasizes that it’s due to someone contracting measles abroad, when the general definition of elimination doesn’t say that: “In public health, elimination refers to the reduction of a specific disease's incidence to zero in a defined geographic area as a result of deliberate efforts, although continued interventions are necessary to maintain this status.” Does that graph demonstrate a cyclic time trend, even if irregular, maybe?

Those are this infectious disease epidemiologist’s thoughts.