How The Coronavirus Vaccines Affect Long-Haul COVID-19 Patients
SARAH MCCAMMON, HOST:
The vaccines now being widely deployed have been tested and assessed to be highly effective. What about for people who've already contracted coronavirus, have COVID-19 and are still experiencing symptoms like coughing, fatigue, shortness of breath and chest pains for weeks and sometimes months? These so-called long-haulers were not included in vaccine trials, so we'll ask Akiko Iwasaki about them. She's an immunologist at Yale, and she joins us now. Welcome to the program.
AKIKO IWASAKI: Thank you, Sarah, for having me.
MCCAMMON: So, first of all, what do you think causes the long-haul symptoms in some COVID-19 patients?
IWASAKI: I have a couple of theories about this. The long-haul symptoms can be caused by either a persistent viral infection or viral remnant that remains in the people who are essentially feeling this inflammation from responses to these remnants or reservoir. The second possibility is that long-haul is caused by autoimmune responses. So a person's immune response now attacking host cells or host factors - that is driving the symptoms that they're experiencing.
MCCAMMON: How much do we know about which patients might be the most susceptible to this?
IWASAKI: So we're learning a lot about the demographics of the long-haulers. And we're seeing that even people who suffer from milder symptoms who are never hospitalized go on to develop long symptoms. And these appear to be occurring more dominantly in women of younger age compared to the severe COVID and lethal COVID that we see in older age group.
MCCAMMON: In a survey of long-haulers, about a third reported that symptoms lessened after they received the vaccine. About a fifth said they got worse, and about half were about the same. From a scientific standpoint, what do you think the effect of the vaccine should be on COVID long-haulers?
IWASAKI: Before I started seeing these reports, I actually had no expectation that long-haulers would feel better after the vaccine, so I was delighted to see that 30 to 40% of the people are actually reporting improvement in their symptoms after getting the COVID vaccine. And so the reason for them getting better with the COVID vaccine - it can be - again, two different reasons can explain that.
One is that if there is this residual virus replication or viral remnants that's causing this long-haul symptom, then the vaccines are known to induce very robust immune response that can clear these reservoirs and essentially eliminate the cause of the problem. The second possibility is that the vaccine is stimulating the cytokines in the innate immune response that will, at least temporarily, dampen the autoreactive T cells or B cells, and they might be feeling better because of that.
MCCAMMON: So the vaccine is kind of helping along the body's immune system? Am I getting that right?
IWASAKI: That's right. So, yeah, it - the vaccines are helping the immune system fight off the residual viral infection or reprogram the autoreactive cells that are attacking our own cells.
MCCAMMON: The survey I mentioned a moment ago reported really disparate experiences, though, among COVID long-haulers after they got the vaccine. A lot of them said they were about the same, and some said they thought they got worse. I mean, how do you explain those different reactions?
IWASAKI: So I think we have to think about the long-hauler disease as not being caused by one reason, but there may be multiple reasons why people are feeling these symptoms for a long, extended time period. So let's say, you know, maybe a part of the long-haulers are feeling ill because of the residual viral infection, and others are feeling worse because of autoimmune reaction. So the fact that not everybody's feeling better after the vaccine indicate that there may be multiple reasons why people are suffering from long COVID.
MCCAMMON: Based on what you know right now, bottom line, do you think people who've had COVID-19 and are still feeling the effects should get vaccinated?
IWASAKI: Yes. People who've had the COVID and who recovered from it or people who are suffering still from the impact of COVID should get vaccinated because the studies have shown that there is no negative effect of getting the vaccine and that you might even feel better from getting the vaccine.
MCCAMMON: Akiko Iwasaki is an immunologist at Yale. Professor, thanks so much.
IWASAKI: Thank you, Sarah. Transcript provided by NPR, Copyright NPR.