With only a few days left to close the year of 2020, the time is right to reflect on how the year has gone by. The Covid-19 started spreading rapidly around the globe early this year and it is hard to realize that we have spent almost a year in this pandemic. Almost all of us have spent this year by social distancing, isolating, working remote, and limiting or restricting travel plans altogether to protect not just our loved ones but also our neighbours and even the people whom we don’t know — all to limit the spread of the contagious coronavirus. The deadly Covid-19 virus has infected nearly 80 million people worldwide so far and it has taken a toll on over 1.7 million lives (Source: Google).
Vaccines are biological machines or molecules that can power our immune system to offer protection against the deadly coronavirus. When a sufficiently large population is given the coronavirus vaccine, more people would have become immune to the virus. For Covid-19 to keep spreading, it needs to infect individuals who are not immune, but the virus would fail in this process if it infects individuals who are already immune from taking vaccines. The point at which the virus cannot spread anymore is referred to as having achieved the herd immunity. But to achieve the herd immunity on a large scale, we need vaccines in the first place and the entire world has been closely watching for these mighty molecular machines. In the past few months, there was a lot of discussion around the different vaccine technologies, their effectiveness and side effects, as well as the storage conditions and logistical challenges of keeping the vaccines in an active state before being delivered to the patients. So, where do we exactly stand in terms of developing a vaccine and when do we expect to achieve the herd immunity?
Who are the front runner candidates?
Several biotech and pharma companies around the globe have flocked to the race of developing vaccines to beat the novel coronavirus. Vaccine candidates are being developed and clinically tested using various technologies, for example, viral vector, DNA or RNA, or protein-based . Due to the faster development timeline, the mRNA-based vaccines developed by Pfizer/BioNTech and Moderna have gained early traction in the scientific community. To everyone’s surprise, these vaccines boosted effectiveness hovering around 95%, which is well above the 50% threshold set by the FDA and the 40% levels seen with the Flu vaccines .
Who can get the vaccines?
In the US, the FDA granted emergency use authorization (EUA) for Pfizer’s vaccine early December in individuals over 16 years, and shortly a week after, Moderna’s vaccine has also been granted the EUA for people over 18 years [3, 4]. While a EUA is not the same as the full approval, the emergency authorization cautiously grants the use of vaccines in certain individuals as determined by the regulatory body. Because there is insufficient information on the effectiveness of the vaccine in children and pregnant women, they are currently not eligible to receive the vaccines but clinical trials are underway for these patient groups . The UK and Canada were among the first set of countries to issue emergency use, which was followed by the US and the European Union. It is expected that more countries will join this list to make these vaccines available to their fellow citizens .
What to expect after getting vaccines?
The currently available Pfizer and Moderna vaccines’ need to be administered in two doses that are given at least 3 to 4 weeks apart, and it is essential to receive the two shots in order to get full protection from the virus. The clinical trial results from a two to three month follow up of participants have shown that these vaccines can cause mild to moderate symptoms, but experts say these symptoms are a result of the immune system working hard to protect us from Covid-19 . It should also be kept in mind that these symptoms are not specific to the coronavirus vaccines but other vaccines such as the flu vaccine can also cause side effects such as fever or fatigue .
Some individuals with a history of allergy could potentially experience anaphylaxis, a rare life-threatening allergic reaction, but it is unclear whether an ingredient in the vaccine causes this or people with allergies are especially sensitive to the vaccines. This has been reported in the UK in two individuals, who have successfully recovered after taking EpiPen, and as a result, the UK regulators have restricted access to the Pfizer vaccine for individuals with a past history of anaphylaxis.
The year of 2020 may have started on a negative note with Covid-19 spreading rapidly around the world, but we are ending this year on a positive note with at least two vaccines already having received the EUA and a few others that are in the late-stage clinical development expected to show results in early 2021. It is true these vaccines have side effects with some individuals experiencing mild to moderate symptoms, but as the experts suggest, the protection coronavirus vaccines offer far outweighs the side effects. Latest reports indicate that over 4 million vaccine doses have been administered successfully in nine countries and while we are far from reaching the herd immunity, this gets us one step closer towards that ambitious goal. Let us all hope, the year of 2021 will bring back the normalcy we all yearn for!!