The COVID-19 vaccine is right around the corner, and it won’t be one vaccine, but several…maybe lots.
What do we know about them?
The old school way to get immunity to a disease is to get the disease. When I was a kid and had the mumps, all the neighbors sent their kids to visit, so they could get the mumps, too. Safer to get mumps as a child than as an adult.
Another way to get immunity is to be exposed to a weakened form or inactive actual virus—which promotes the immune system to respond, but doesn’t actually make you sick. Measles and chickenpox vaccines are these. But that’s not what we’re dealing with in most COVID-19 vaccine trials likely to be used in the U.S.
If you need to stop a car from getting to its destination, you have many options: remove the driver, drain the fuel, blow out a tire, blockade the road, poke a hole in the radiator.
There are also lots of different ways the body fights a virus, and different vaccine approaches tackle the problem in different ways.
There are dozens of different vaccine trials underway. They go through a range of trials to prove they work and that they’re not dangerous. Some fall by the wayside due to problems of various kinds, including side-effects, not a strong enough immune response, and any of a lot of other issues.
The companies whose vaccines seem nearest approval in the United States are Pfizer, AstraZeneca, Moderna and Johnson&Johnson, not necessarily in that order. Pfizer and Moderna have already asked for emergency FDA approval for release in the United States.
Russia and China have actually released and are using vaccines, but these have not gone through all the safety and effectiveness trials that most Western medical officers recommend.
Pfizer and its partner BioNTech have actually released a vaccine in England. It is BNT162b2, which is approved for emergency use in the United Kingdom, and which they say is more than 90 percent effective and has few side effects (like fatigue or fever). One bonus is that it has high effectiveness in elderly people, who sometimes don’t respond well to vaccines.
But there are many more vaccines in the pipeline.
So how are vaccines different? (Caveat: This is hyper complicated, so these brief paragraphs are more place markers than useful descriptions.)
There are the nucleic acid vaccines, which use bits of the genetic code of the virus (but not the actual virus) to train your immune system to recognize and fight the virus. The Pfizer and Moderna vaccines use this technology.
Viral vectored vaccines use a harmless virus to ferry a fragment of the COVID genetic material to the immune system, so it can recognize and fight the virus if you’re exposed. The AstraZeneca/University of Oxford and Johnson&Johnson vaccines use this technology.
Protein subunit vaccines introduce isolated COVID-19 proteins from the virus into the body. They can’t introduce the disease, but they can produce an immune response. Novavax has the vaccine with this technology that’s closest to approval.
Chinese and Indian companies are leaders in working on inactivated or weakened virus vaccines, which is a more traditional vaccine technology, but the vaccine can take a long time to manufacture.
Here is a Washington Post piece on the various technologies, with a little more detail.
Some of the vaccines require two doses for full effectiveness. (Johnson&Johnson’s is a one-dose vaccine.) Some need special care in handling, like super cold temperatures—but while that can require specialized refrigeration units, they can generally be transported in coolers on dry ice to immunization facilities. So you don’t need all that many high-tech freezers.
If you’re following the vaccine issue, you know that one of the big issues is when vaccines will be available in large amounts and who gets a vaccination first. The AARP has a piece reviewing the state of vaccine issues here.
There is a fairly straightforward approval process. First, the Food and Drug Administration is authorized to issue an Emergency Use Authorization. As mentioned earlier, Pfizer and Moderna have already applied; others aren't far behind.
Emergency Use Authorization by the FDA is permitted in emergencies like a pandemic. The organization itself says it “may allow the use of unapproved medical products, or unapproved uses of approved medical products in an emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions when certain statutory criteria have been met, including that there are no adequate, approved, and available alternatives.” More data here.
Once the FDA does its part, the ball is the court of the Centers for Disease Control and its Advisory Committee on Immunization Practices, which not only decides whether to approve, but who should get it. The committee has already voted that the first recipients will be “health care personnel, other essential workers, adults with high-risk medical conditions, and adults aged ≥65 years (including residents of long-term care facilities.)”
It’s a big deal and there’s lots of pressure, so prognosticators are suggesting approval could happen before Christmas, or at least before the end of the year.
Meanwhile, officials in every state are setting up their vaccine distribution plans. And yes, that includes Hawai`i. You can learn more about our state's vaccination program here.
© Jan TenBruggencate 2020
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