New variants of COVID-19: What if they hit the world again?
We do have the bitter experience of not being able to develop a dengue vaccine till date. The reason behind this is the presence of multiple serotypes. When there is an infection of one serotype, it may confer safety to that serotype but not to others. Similar may be the case with COVID-19
The world is still suffering from the COVID-19 pandemic that started a year back, affecting all continents and claiming more than 1.6 million lives. With the approval of COVID vaccines for public use, the hope of becoming free from the disease has elevated though there is no certainty that the people in all parts of the world will get the vaccines on time.
On the one hand, there are currently more than 50 COVID-19 vaccine candidates on trial. On the other hand, a new variant of the coronavirus that has been found growing fast in some parts of the world is causing concern. The new COV- ID-19 strain, which is said to be up to 70 per cent more transmissible than the original, has already compelled several countries to shut down their borders and implement lockdowns.
The genetic information in many viruses changes or mutates very rapidly, and sometimes these changes can benefit the virus by allowing it to transmit more efficiently as vaccines may not work for all the variants.
So, vaccines need to be frequently updated.
Coronaviruses evolve more slowly than viruses like the flu but do pick up mutations as they spread.
SARS-CoV-2 has been adding one or two changes a month to its RNA genome since it emerged in China.
Today, at least eight strains of the coronavirus are making their way around the globe, creating a trail of deaths and diseases.
The changes or mutations involve the spike protein - the part that helps it to infect cells, and the target COVID vaccines are designed around this. Two distinct sets of mutations in the virus have been identified that cause COVID-19, the H69/V70 deletion and the D614G, both affecting the spike protein, which helps the virus to bind to the human cell and infect it. And a new strain of the coronavirus, B.1.1.7, has been confirmed in the Netherlands, Denmark, Italy, Iceland and Australia.
There are many problems associated with the rise of new variants of COV- ID-19. The first is that vaccines recently made available could be ineffective against them. As the new variant is seen, the targeted portion of the spike protein may not work effectively by vaccination due to altered responses in them. The leading vaccines were designed to trigger the immune system to make antibodies that can recognise and block the spike proteins, so it is possible that changes to the spike could alter how well the vaccines work.
The second issue is there could be more severe symptoms or varied symptoms that could be more deadly. The third may be their fast replication, or maybe their transmission or mutability rate could be higher as compared to other strains. So, the transmission of new variants may bring much distress in people as the second wave of transmission to larger numbers of people in a single day indifferent parts of the world has been a matter of concern.
There arises a huge question regarding the efficacy of the vaccines developed.
As the recent vaccines have been developed targeting the eight mutants that are seen today, if new variants are seen, the recent vaccines may not function.
Also, no clear study has been made to see if such vaccination will provide long-term immunity or not. The chances that the antibodies that were built in the first infection might not work against the new variants pose a great threat and is becoming a matter of concern to scientists all over the world.
Different countries may have a different mutated form of the virus, and the vaccine targeted towards one strain of the virus may not work effectively on others.
Hence, it is necessary to study genetic changes that have been seen in different strains of the virus and know their actual pathogenicity.
Only after this, targeted vaccination can be developed with increased efficiency.
We do have the bitter experience of not being able to develop a dengue vaccine till date. The reason behind this is the presence of multiple serotypes.
When there is an infection of one serotype, it may confer safety to that serotype but not to others.
Also, new versions of the influenza vaccines are developed twice a year, as the influenza virus changes rapidly. Similar may be the case with COVID-19, if a mutation occurs and there are multiple variants, this may cause havoc to the health system.
In Nepal, many COVID patients are found recovering in 7-10 days while some are still virus-positive for 22-26 days. This might be due to two factors: one due to the type of immune response they have developed and the other due to the different strain of the virus circulating.
Nepal lacks a coordinated sequencing system and a national database to ensure that viral samples are being collected and sequenced from groups of patients in a way that’s representative of the geography and demographics. We are still unable to identify which strain of COVID-19 is circulating and don’t know if the vaccines being developed will work.
Besides these, our country is still dilly-dallying to purchase the vaccines and we have not come up with well-equipped laboratories for storage and transport.
Learning from last year’s pandemic, we need to formulate strategies to protect ourselves from such pandemics in the future. Keeping in mind the onset of new variants of COVID-19 in different parts of the world, we must be well prepared to tackle them. Research should be focussed on finding the circulating mutants in time so that an effective vaccination programme can be introduced.
Thus, it is necessary to make all out efforts to control the disease by launching an effective vaccination programme at the earliest.
Since our country depends on other countries for the vaccines, it is necessary to get all the logistics in place.
Lamsal is in-charge of TU Biotech Corona Laboratory