The term coronavirus was not frequently used in daily lexicon until the novel strain of virus, scientifically known as SARS-CoV-2, dramatically spread across the globe. The worldwide pandemic has impacted many ‘normal’ day-to-day activities and continues to cause widespread disruption, even as ‘lockdown’ measures are gradually eased.
In a relatively short period of time, our understanding of factors of the COVID-19 disease have changed.
Dr Daniel Atkinson, Clinical Lead at Treated.com, said, ‘Whilst the scientific world has seen other strains of coronavirus before, this particular strain of coronavirus is new and so our knowledge base has had to be built almost from the ground up. As more studies are completed and the results analysed, researchers are able to get a better picture of how this virus works and managed to reach pandemic-level.’
Here we will take a brief look at:
- What we’ve learned about how coronavirus is transmitted
- Why the rules on face masks have changed
- How many people carry the virus but don’t show symptoms
- Which treatments are working
- When we can expect a vaccine
- And when we can expect to return to ‘normal’
How coronavirus is transmitted
Chinese health officials initially thought that the virus was not easily passed between humans. It soon transpired however that this was incorrect, as the number of infected people dramatically increased.
The virus is thought to be mainly contracted by coming into contact with an infected droplet, whether this is through your eyes, nose or mouth. Initially there was heightened concern that the virus could potentially live for several days on surfaces. However, the laboratory results that suggested this were not conducted using live virus and were under lab conditions.
When is it passed on?
The rapid spread of the coronavirus has indicated that it can transmit very early on in the infection period. Unlike the disease known as SARS, which was found mostly to transmit once people were experiencing severe symptoms and often hospitalised.
One study suggested that around 43% of infectors passed on the virus before the onset of their symptoms. The time between exposure to the virus and symptom onset is estimated to be between three and 14 days. However, symptoms typically appear four to five days after exposure.
As more data and knowledge has been gathered, it has become apparent that there is a higher risk of transmission in poorly ventilated spaces, as infected particles may remain suspended in the air. Further data has suggested that it could be possible for the infection to be passed on when simply talking or breathing. These particular characteristics of coronavirus may have had an impact on the change in advice when it comes to face masks.
The efficacy of face masks
At the beginning of the pandemic, many authorities took the stance that face masks would only be beneficial for those who are sick or presenting symptoms. However, over time there has been further evidence to suggest that it is possible to have the virus, and be contagious, whilst asymptomatic. This means that unsuspecting carriers can spread the disease.
Scientists know that it is possible for a simple face covering to stop the spread of some droplets from the wearer’s mouth and nose. This means that if you already have the virus, but do not have symptoms and are therefore not self-isolating, you can significantly reduce your chances of transmitting it to other people by wearing a mask. It is also possible that wearing a mask does offer some protection to the wearer as well.
When should I wear a mask?
In England, face masks must be worn inside shops from 24th July. The information on the wearing of face masks in public places has gone through periods of change. The wearing of face masks was only initially implemented in hospital settings, and then from 15th June they became mandatory on public transport.
Now that lockdown restrictions have been eased further and the general public is potentially mixing more, the use of face masks has become more important. Especially in places where the 2-metre distancing rules cannot be maintained.
There is limited clinical data on exactly how effective wearing a face mask is in the fight against a disease such as COVID-19. However, according to a report by The Royal Society, ‘There have been no clinical trials of coughing into your elbow, social distancing and quarantine, yet these measures are seen as effective and have been widely adopted.’
Countries where citizens already frequently wear masks when in public have reported encouragingly lower infection rates.
The guidance on wearing face masks differs depending on the country you are in. Please check with your local government authority for further information.
How many people don’t develop symptoms?
The exact percentage of people who contract coronavirus but don’t go on to develop symptoms is difficult to pin down.
The scientific community is still trying to understand why some people exhibit an extremely strong reaction to the virus while others don’t notice that they’ve been infected. One study published in April plotted the number of asymptomatic carriers at close to 80%.
A study that focused on an Italian village found asymptomatic cases to be between 50%-75%.
Research carried out by Imperial College London found that 69% of those involved did not report symptoms on the day of the test or during the previous week. However, some did report that they went on to develop symptoms later.
Dr Atkinson says: ‘The fact that coronavirus can be carried without symptoms means that the social distancing and hand-washing aspects of protection are still extremely important.
‘Those with coronavirus symptoms are able to adhere to the self-isolation guidelines, whereas those who are unaware that they have the virus can remain active in society and unknowingly infect others.’
There are still numerous estimates on how many people have coronavirus and don’t develop symptoms. Even armed with data on how many people have antibodies to the virus, it is still unclear what level of protection (if any) they can offer.
What treatment is effective?
As the worldwide number of cases surpasses 16 million, there are still numerous trials taking place to establish an effective treatment for the condition.
The timeline for a new drug to go from conception to market can be an extremely long one. Therefore, one of the quickest ways to establish a treatment is to try ones that are already being used to treat other conditions.
Some treatments have gone through the trial process and have subsequently been written off, whereas others have gained further interest.
- Antiviral drugs (such as remdesivir and arbidol) are being studied to see if they can help patients at the early onset of the virus before it has had time to rapidly multiply.
- Dexamethasone is a corticosteroid drug used to treat several inflammatory conditions and has shown promising results in the treatment of hospitalised coronavirus patients. There are significant risks if dexamethasone is taken unsupervised, so people with coronavirus symptoms shouldn’t take it if they’re recovering at home.
- A formulation of ibuprofen has gone on to be investigated to see if it can help combat acute respiratory distress syndrome (ARDS), an inflammatory response triggered in the body whilst trying to fight the virus.
When will we see a vaccine?
Research into a coronavirus vaccine continues across the world, with over 40 vaccines under different stages of development. However, the timescale for an effective vaccine to become readily available is still unknown. Some experts suggest that a vaccine may become available by mid-2021, but this may prove to be overly optimistic.
It was only back in May that we were told that the worst case scenario would be that we would never find a vaccine. However, more recently scientists in Oxford have made significant progress with human trials of a promising vaccine. The Phase I/II trial of the vaccine was found to provoke both a T cell and an antibody response. The strongest immune response was noted in participants who were given a second booster and this may form part of the immunisation strategy we eventually adopt.
Dr Atkinson says: ‘A vaccine against coronavirus will be undoubtedly important and the results from The University of Oxford vaccine trials are looking promising. However, it is still difficult to estimate when we are likely to see a vaccine programme being rolled out across the country. If we draw similarities to the influenza vaccine, we might expect that a coronavirus vaccine offers some protection against the disease but does not completely eradicate it.’
The next stage of trials are taking place in countries across the world and will include people over the age of 55.
When can we go back to ‘normal’?
As mentioned at the start of this article, the coronavirus pandemic has dramatically changed how we conduct our day-to-day lives. For the time being, it is difficult to say when or if things will ever go back to the way they used to be.
Maintaining social distancing measures, more frequent washing of hands, wearing of face masks in enclosed spaces and a heightened awareness of not touching one’s face could all become part of the new ‘normal’. As we continue to learn more about this virus, the measures we have in place to keep safe could change or be reinforced as we navigate the waves of the disease.