What we know about the Covid breakthrough in Washington state – and what we don’t know

How common are breakthrough cases in Washington State?

Not common at all.

From January 17 to July 24, only 0.1% of fully vaccinated Washingtonians tested positive for Covid.

And only 52 of the estimated 4 million Washingtonians who were fully vaccinated died from Covid. Thirty-seven of them had pre-existing conditions and, for 15 of them, it is not known whether they had pre-existing conditions or not. Their median age was 83 years old.

Getting vaccinated is the surest way to avoid the disease.

Are all breakthroughs counted?

Probably not.

There are likely asymptomatic infections among fully vaccinated people that the state is unaware of, but some health experts say we shouldn’t call these “breakthrough cases.”

This is because after receiving the vaccine, you can still come into contact with the virus, inhale it, and test positive – but not get sick. And in this case, the vaccine does its job. It prepared your immune system to kill the virus before it caused Covid.

So these experts say we shouldn’t call it a breakthrough ‘case’ until there are real symptoms, because that’s when the virus actually went through the vaccine.

But can these people who have the coronavirus in their nostrils transmit it?

That’s a question researchers are working on right now: how often fully vaccinated people unknowingly pass the virus on to unvaccinated people – like their children, for example. We do not know yet.

But we do know that the virus slows down a lot in communities where most people are vaccinated, so it seems the vaccine makes transmission less likely.

And we know that even when vaccinated people get an infection, they usually have less virus in their bodies – so they’re less likely to pass it on.

Some researchers worry that this is less true for the delta variant: that perhaps vaccinated people may have a high “viral load” in their nasal passages (even though the virus never reaches their lungs and makes them sick) and may therefore easily pass this variant on to others.

Most studies on this topic end this fall, but each new variation will bring new uncertainty to the question.

What about long term symptoms if you are a breakthrough Covid case?

There is reason to believe that you are unlikely to contract long-distance Covid if you have been vaccinated.

One explanation for the long Covid is that it is a deregulated immune response, and the immune system of those vaccinated should, on the whole, be able to respond fairly effectively to the coronavirus.

But a small study of fully vaccinated health workers in Israel found some long-haul Coviders, particularly people with persistent fatigue after a fairly mild infection.

So this is worrying, because it seems like it’s possible – we just don’t know how likely it is – that fully vaccinated people will have Covid for a long time.

Are public health officials doing something to try to curb the breakthrough of Covid?

The main thing they do is focus on vaccinating people. We know that vaccinated people are well protected against hospitalization and death, and they are probably much less likely to transmit the virus.

So the more people are vaccinated, the less the virus will circulate in the population, and the more everyone will be protected.