NIH communications with patients have faded in late 2021, although Nath says work continues behind the scenes. The withdrawal caused bewilderment and dismay among patients who spoke to Science, who said NIH researchers were the only ones helping them.
Now, a small number of other researchers around the world are beginning to investigate whether the still poorly understood Long Covid biology itself overlaps the mysterious mechanisms that drive some post-vaccine side effects.
More discreet side effects linked to COVID-19
vaccines have been recognized, including a rare but severe bleeding disorder occurring after the AstraZeneca and Johnson & Johnson vaccines and cardiac inflammation, documented after messenger RNA (mRNA) vaccines.
produced by Pfizer and Moderna. Investigating possible side effects presents a dilemma for researchers: they risk fueling the rejection of vaccines that are generally safe, effective and crucial to saving lives.
You have to be very careful” before tying COVID-19 vaccines to complications, warns Nath. “You can draw the wrong conclusion. … The implications are enormous ”. And complex and persistent symptoms like Dressen’s are even more difficult to study because patients may not have a clear diagnosis.
At the same time, understanding these issues could help those currently suffering and, if a link is unmasked, help guide the design of the next generation of vaccines and possibly identify those at high risk for serious side effects. “We shouldn’t be against adverse events,” says William Murphy, immunologist at the University of California, Davis.
In November 2021 in the New England Journal of Medicine, he proposed that an autoimmune mechanism triggered by the SARS-CoV-2 spike protein could explain both Long Covid symptoms and some rare vaccine side effects, and called for more background research to investigate. probe possible connections.
“Reassuring the public that everything is done, from a research perspective, to understand vaccines is more important than simply saying that everything is safe,” says Murphy. Like others, he continues to urge vaccination.
Echoes of Long Covid?
The frequency with which side effects such as Dressen’s occur are unclear. Online communities can include many thousands of participants, but no one is publicly monitoring these cases, which are variable and difficult to diagnose or even classify. Symptoms also include fatigue, severe headaches, nerve pain, changes in blood pressure, and short-term memory problems. Nath believes they are “extremely rare”.
Long Covid, by contrast, affects anywhere from 5% to about 30% of people infected with SARS-CoV-2. Researchers are making tentative progress with several ideas about the underlying biology.
Some studies suggest that the virus can in some cases linger in the tissues and cause permanent damage. Other evidence indicates that the side effects of the original infection may play a role even after the body has cleared the virus.