Long Covid

Covid-19

Coronavirus Goodbye Kiss

Light at the End of the Tunnel

On May 5, 2023, the World Health Organization announced that the SARS-CoV-2 pandemic is now “an established and ongoing health issue which no longer constitutes a public health emergency of international concern.”

Since it was first reported in China in December 2019, the coronavirus has infected over 767 million people around the world, and killed almost seven million.

As the Covid pandemic fades, its long-term aftermath continues to build in the form of so-called ‘Long Covid’.

Post COVID-19 Condition, as the WHO calls it, is defined as the “the continuation or development of new symptoms 3 months after the initial SARS-CoV-2 infection, with these symptoms lasting for at least 2 months with no other explanation.”

Common long-haul Covid symptoms include fatigue, shortness of breath and cognitive dysfunction. A dizzying number of other symptoms have also been reported, including hair loss and skin rashes.

According to the WHO, between ten and twenty percent of those infected by SARS-CoV-2 may develop Long Covid.

Health Canada reports that about fifteen percent of the 4.7 million Canadians who suffered one or more bouts of SARS-CoV-2 infection have experienced symptoms for three or more months following their encounter with the RNA virus. Almost half have had symptoms for a year or longer.

One of these long-haul Covid sufferers is Manali Mukherjee, an Assistant Professor of Medicine at McMaster University, in Hamilton, Ontario.

Mukherjee and her colleagues are now working with a cohort of 120 Long Covid patients, trying to tease out what’s causing their prolonged symptoms. The likely culprits: persistent, low-level infection by viral particles hiding inside cells, and — more likely — long-lived autoimmune responses to infection, after viral particles have been eliminated.

Their research task is devilishly complicated, all the more so given the difficulty of establishing a ‘control’ group.

In an ideal world, the presence or absence of signs and symptoms, alongside blood workups of Long Covid patients – before, during and after initial infection – would be compared with people who never got infected, over the same time period.

‘Longitudinal’ studies like this are the gold standard in infectious disease epidemiology, but challenging to assemble.

Among the primary aims of the McMaster researchers – to find out if there’s an association between Long Covid pathology and the presence of ‘rogue antibodies’ and ‘cytokines’ (‘cell movers’) in patients’ blood. Those antibodies would attack the patients’ own tissues, prompting an autoimmune response; cytokines would activate and mobilize blood cells that mediate inflammatory responses.

Among the most potentially troublesome cytokines – Interleukin (IL) 1-β, IL-6 and IL 8, and Tumor Necrosis Factor (TNF)-α.

From an entirely different angle, Mukherjee and her colleagues suspect that socioeconomic factors may play a role in prolonging Covid symptoms. People who drive themselves too hard, who don’t take time to rest and recover (perhaps because they can’t afford to do so), may be most susceptible to long-term Covid.

The epidemiology of Long Covid bears this out. Young adults — especially working women with families — are most likely to suffer long Covid.

But there’s light at the end of the tunnel, Mukherjee says. According to the McMaster immunologist, people should listen to their bodies, and be patient. Long Covid will almost certainly not last forever.

Listen to my conversation with Manali Mukherjee. Click on the SoundCloud link.