Why do some patients with Covid-19 show symptoms long after the virus has cleared? NIH aims to find out.

The National Institutes of Health have announced the first phase of their four-year, billion-dollar initiative to learn more about why some Covid-19 survivors show long-term symptoms, even after the virus left the body.

The group of patients is known as “long-haul”, although the NIH calls the condition “post-acute sequelae of SARS-CoV-2 infection” or PASC. (The word “sequel” comes from Latin, meaning a condition that occurs as a result of an illness. The word “sequel” has the same origin.)

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NIH research aims to learn how SARS-CoV-2, the virus that causes Covid-19, could eventually lead to lasting symptoms, such as deep fatigue, brain fog, headaches, fever, and shortness of breath.

Symptoms “can range from mildly bothersome to truly incapacitating,” Dr Anthony Fauci, director of the NIH National Institute of Allergy and Infectious Diseases, said in a White House briefing on Covid-19 on Wednesday.

“We believe that the knowledge we gain from this research will also improve our knowledge of the basic biology of how humans recover from infection and improve our understanding of other chronic post-viral syndromes. and autoimmune diseases, ”NIH Director Dr. Francis Collins said in a statement Tuesday.

Congress previously allocated $ 1.15 billion to the NIH to study long-haul. This money will be spent over four years. The research announced this week is the first in a series of such projects.

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The researchers “will be looking at large databases for resources, such as electronic health records and health symptoms, and they will study a number of biological specimens,” Fauci said.

The research initiative also hopes to answer questions as to how many Covid-19 survivors might be affected, who might be the most vulnerable, as well as what might be the underlying cause of the symptoms in the long term.

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A study from Wuhan, China, published last month, found that symptoms of Covid-19 could persist for up to six months.

Of about 1,700 patients, 63% said they were still suffering from fatigue or muscle weakness six months later, and about a quarter reported persistent anxiety or depression, as well as trouble sleeping.

“We don’t yet know the extent of the problem, but given the number of individuals of all ages who have been or will be infected,” Collins wrote, “the impact on public health could be profound.”

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