A year ago, I wrote an article for The Conversation about a mysterious pneumonia outbreak in the Chinese city of Wuhan that turned out to be the start of the COVID-19 pandemic.
At the time of writing, very little was known about the disease and the virus that caused it, but I cautioned against the concerns surrounding emerging coronaviruses, citing SARS, MERS, and others as important examples.
Since then – and every day since – we’ve been learning so much about SARS-CoV-2 and COVID-19, finding new ways to control the pandemic and no doubt keep us safer for decades to come.
This is what we have learned since January last year and what we have yet to learn.
Lesson learned
Initially, the disease we now call COVID-19 was described in terms of pneumonia, or pneumonia, in older people. But we now know that SARS-CoV-2 infection can lead to a wide variety of symptoms in people of all ages, ranging from no symptoms at all to systemic inflammation and death.
And then there are the lingering symptoms that bother many – the so-called “long COVID”. We are also starting to break down the different phases of the disease, damage to organs (such as the heart and brain) and the role of co-infections with bacteria and fungi.
As of January 2020, there was limited evidence of human-to-human transmission. If so, it was thought to be similar to its cousin virus SARS-CoV-1, which causes SARS by spreading the infection relatively late in the disease, when symptoms are at their peak.
Still, early studies showed that inter-human spread was very efficient for SARS-CoV-2, and that it could happen quickly and before the worst symptoms started. This made it difficult to control without sensitive and specific tests using the now famous PCR test.
Social distance, hygiene and masks would help limit the spread in addition to isolation and quarantine.
Initially, there were no treatments or vaccines for COVID-19, other than hospital support, such as providing oxygen if patients had difficulty breathing or antibiotics if they contracted a secondary bacterial infection.
In the months following January, researchers have been rapidly testing new therapies against COVID-19, identifying dexamethasone, and have developed many safe and highly effective vaccines against COVID-19 that are now in use.
Future questions
Although we learn about COVID-19 on a daily basis, there remain a number of important scientific questions that will determine the future of SARS-CoV-2 and humanity for decades. The first is how will SARS-CoV-2 develop, adapt and change in the coming year in light of natural or acquired immunity through vaccination?
A second, less academic point would be whether this is important. Our treatments and public health measures will still work, but what about our vaccines?
We continue to monitor, predict and understand SARS-CoV-2 evolution with regard to vaccine ‘escape’, and all our available evidence suggests that it is minimal at best and that our current vaccine platforms are robust enough to withstand any changes If necessary.
We also need to stay alert to the possibility of SARS-CoV-2 settling in another species, such as mink.
Then there is the question of how SARS-CoV-2 will interact with the other viruses circulating in humans. The human airways are home to several viruses that circulate together – often in one person.
These viruses promote or hinder the infection of other viruses. We now know that thanks to social distance, the spread of most of our respiratory viruses, such as influenza and RSV, is severely limited.
How will they “respond” when mitigating measures, such as social distancing, are ended?
Finally, we need to identify the origin of SARS-CoV-2 to avoid the continued spillover of SARS-CoV-2-like (or even other pathogenic coronaviruses) to humans.
We know that SARS-CoV-2 probably surfaced recently in Southeast Asia and the virus ended up in a horseshoe nose. But the biological and ecological steps required to reach humans remain unclear.
Solving this puzzle will help protect our health for decades to come, in the same way that swine and bird flu infections do.
As I said in my article a year ago, these epidemics are “a constant reminder of the need to invest in research into emerging virus biology and evolution, and ultimately to identify safe and effective drugs to treat – or vaccines to treat serious diseases. to prevent”. .
The COVID-19 pandemic has shown that science and scientists can and will deliver results with the right financial and social support. How then will we apply the lessons learned from COVID-19 to other serious problems, such as emerging infections, antimicrobial resistance and climate change?
Connor Bamford, Research Fellow, Virology, Queen’s University Belfast.
This article has been republished from The Conversation under a Creative Commons license. Read the original article.