A year ago, I wrote an article for The Conversation about a mysterious outbreak of pneumonia in the Chinese city of Wuhan, which appeared 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 warned of concern about emerging coronaviruses, citing SARS, MERS, and others as important examples.
Since then – and every day since – we continue to learn about both SARS-CoV-2 and COVID-19, finding new ways to control the pandemic, and certainly keeping them safer in the decades to come.
This is what we have learned since last January and what we still need to learn.
Lessons learned
Initially, the disease we now call COVID-19 was described in terms of lung inflammation, or pneumonia, in the elderly. But we now know that SARS-CoV-2 infection can cause a wide range of symptoms in people of all ages, ranging from no symptoms to systemic inflammation and death.
And, in addition, there are the persistent symptoms that many suffer from, the so-called “long CVVID”. We also begin to separate the different phases of the disease, the damage caused to organs (such as the heart and brain) and the role of co-infections with bacteria and fungi.
In January 2020, there was limited evidence of human transmission. If there was, it was thought to be similar to its cousin SARS-CoV-1 virus, which causes SARS, as the infection spreads relatively late when the symptom is at its peak.
However, early studies showed that diffusion between people was very efficient for SARS-CoV-2 and that it could happen quickly and before the worst of symptoms began. This made control difficult without sensitive and specific tests using the famous PCR test.
Social distancing, hygiene, and masks would help limit spread alongside isolation and quarantine.
Initially, there were no COVID-19 treatments or vaccines other than hospital support, such as providing oxygen when patients had difficulty breathing or antibiotics when they detected a secondary bacterial infection.
In the months following January, researchers quickly tested new therapies for COVID-19, identifying dexamethasone, and have developed many safe and highly effective COVID-19 vaccines that are now in use.
Future questions
Although we are learning daily about COVID-19, there are still several important scientific issues that will shape the future of SARS-CoV-2 and humanity for decades. The first is how will SARS-CoV-2 evolve, adapt, and change over the next year to natural or acquired immunity through vaccination?
A second less academic point would be if this is important. Will our public health treatments and measures continue to work, however, and our vaccines?
We continue to track, predict and understand the evolution of SARS-CoV-2 in terms of the “leakage” of the vaccine, and all our available evidence suggests that, at best, it is minimal and that our Current vaccines are solid enough to withstand any change if needed.
We must also be alert to the possibility of SARS-CoV-2 being established in another species, such as mink.
Then there is the question of how SARS-CoV-2 will interact with other viruses circulating in humans. Human airways are home to several viruses that circulate together, often in a single person.
These viruses favor or prevent the infection of other viruses. We now know that thanks to social distancing, the spread of most of our respiratory viruses, such as the flu 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 emerged recently in Southeast Asia and that the virus was eventually found in a horseshoe bat. But the biological and ecological steps he took to reach humans remain obscure.
The solution to this puzzle will help safeguard our health for decades to come, just as it has been achieved for swine and bird flu infections.
As I said in my article a year ago, these epidemics “constantly remind us of the need to invest in research on the biology and evolution of emerging viruses and ultimately identify safe and effective drugs to treat – or vaccines for prevent – serious diseases “.
The COVID-19 pandemic has shown that science and scientists can and will yield results, given adequate financial and social support. How will we apply COVID-19 lessons to other serious issues, such as emerging infections, antimicrobial resistance, and climate change?
Connor Bamford, researcher, Virology, Queen’s University of Belfast.
This article is republished from The Conversation under a Creative Commons license. Read the original article.