A year ago, I wrote an article for Conversation about a mysterious outbreak of pneumonia in the Chinese city of Wuhan, which turned out to be the beginning of the COVID-19 pandemic.
At the time of writing, very little was known about the disease and the virus that causes it, but I warned of concerns about emerging coronaviruses, citing SARS, MERS and others as important examples.
Since then – and every day since – we continue to learn so much about SARS-CoV-2 and COVID-19, finding new ways to control the pandemic and, no doubt, keep us safe for decades to come.
Here’s what we learned from January last year and what else we have to learn.
Lessons learned
Initially, the disease we now call COVID-19 has been described in terms of lung inflammation, or pneumonia, in the elderly. But we now know that SARS-CoV-2 infection can lead to a wide range of symptoms in people of all ages, from no symptoms to systemic inflammation and death.
And then there are the persistent symptoms that many suffer from – the so-called “long COVID”. We are also beginning to destroy the various stages 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 it did exist, it was thought to be similar to its cousin SARS-CoV-1 virus, which causes SARS, because the infection spreads relatively late in the disease, when symptoms are at their peak.
However, early studies have shown that the spread among humans has been extremely effective for SARS-CoV-2 and that it could happen quickly and before the worst of symptoms begin. This made control difficult without sensitive and specific tests now using the famous PCR test.
Social distancing, hygiene and masks would help limit the spread along with isolation and quarantine.
Initially, there were no treatments or vaccines against COVID-19 other than hospital support, such as oxygen supply when patients had difficulty breathing or antibiotics when they caught a secondary bacterial infection.
In the months following January, researchers quickly tested new therapies for COVID-19, identified dexamethasone, and developed many safe and highly effective vaccines against COVID-19 that are now in use.
Future questions
Although we learn daily about COVID-19, there remain some important scientific questions that will shape the future of SARS-CoV-2 and humanity for decades to come. The first is how will SARS-CoV-2 evolve, adapt and change over the next year in the face of natural or vaccinated immunity?
A second point, less academic, would be whether this is important. Our public health treatments and measures will continue to work, but what about our vaccines?
We continue to track, predict and understand the evolution of SARS-CoV-2 in terms of 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 must also pay attention to the chance that SARS-CoV-2 will settle in another species, such as mink.
Then there is the question of how SARS-CoV-2 will interact with other viruses circulating in humans. The human respiratory tract is home to several viruses that circulate together – often in a single person.
These viruses promote or prevent the infection of other viruses. We now know that due to social distancing, the spread of most of our respiratory viruses, such as influenza and RSV, has been severely restricted.
How will they “react” when mitigation measures, such as social distancing, end?
Finally, we need to identify the origin of SARS-CoV-2 to prevent the continued spread of SARS-CoV-2 (or indeed other pathogenic coronaviruses) in humans.
We know that SARS-CoV-2 probably appeared recently in Southeast Asia and that the virus was finally in a horseshoe bat. But the biological and ecological steps taken to reach people remain obscure.
Solving this puzzle will help protect our health in the coming decades, in the same way that swine and bird flu infections have been achieved.
As I said in my article a year ago, these epidemics “are a constant reminder of the need to invest in research into the biology and evolution of emerging viruses and, ultimately, to identify safe and effective drugs to treat – or vaccines to prevent – serious diseases ”.
The COVID-19 pandemic has shown that science and scientists can and will deliver results, given the right financial and societal support. How will we apply COVID-19 lessons and other serious issues, such as emerging infections, antimicrobial resistance, and climate change?
Connor Bamford, researcher, Virology, Queen’s University Belfast.
This article is republished from Conversation under a Creative Commons license. Read the original article.