Dr. Shyam P Lohani

Let us hope that with the help of an ongoing massive immunisation drive, seasonality, and naturally acquired immunity, there will be a substantial decline in the number of deaths and hospitalisations related to COVID-19 in the coming days. The handling of the COVID-19 pandemic is different in different countries which have led to unequal impacts, and people in many countries have been disproportionately more impacted. The mortality rates are also significantly different among countries.

Crisis
The possibility of reaching herd immunity against SARS-CoV-2 is low simply because significant proportions of the population in our country are not eligible to be vaccinated and some percentages of eligible individuals will possibly decline to be immunised. With about 40 per cent of the population under the age of 18 and the vaccination of population between 12-18 years have not yet been initiated in our country will make herd immunity not possible soon.

Science has revealed much about SARS-CoV-2 and achieved extraordinary and unprecedented progress on the development of COVID-19 vaccines. But the world is still in great uncertainty as the pandemic continues to surge. COVID-19 vaccination drives are being rolled out in many countries, but this does not mean the crisis is close to ending. We are experiencing series of waves owing mainly to mutations of the virus into new and more contagious variants. Although, we are moving towards a new phase mainly due to a huge inoculation drive and millions of infections that may have resulted in acquired and/or natural immunity.
The future of pandemic depends on the ongoing mutations of the SARS-CoV-2 virus, on our behaviours, and on the decision of the government regarding steps to be taken in order to contain virus spread. The continuous impetus on new vaccine development and on new effective treatments of COVID-19 will determine when the pandemic will come to an end. Unless a huge population is covered with vaccines and acquired and/or natural immunity is long-lasting, the return of the world to normal will not be possible. Therefore, until vaccines roll out covers a significant proportion of the world’s population, it could be catastrophic to relax preventive public health measures prematurely.

With the current rates of vaccination, we must be prepared to live with current containment and preventive measures for at least a couple of more months. There are several determinants that may influence the course of pandemics. At this time, we should be focused to think a global vaccination campaign than a narrow nationalistic approach as coronavirus will continue to mutate among the susceptible populations and may evolve as more contagious as well as pathogenic. There is also the possibility that the available vaccines are less effective against new variants. The reduction of vaccine effectiveness is already seen with the Delta variant.
Owing to huge vaccination campaigns, false optimism about herd immunity can result in premature relaxation of preventive measures and thus lead to repeated outbreaks and surge in cases of SARS-CoV-2 infections. Even if SARS-CoV-2 becomes endemic, the ongoing preventive strategies should be continued. The uncertainty about the duration of vaccine protection and protection against new emerging variants may also lead to the need for booster dose with current or new COVID-19 vaccines. Although the unprecedented pace with which vaccines were developed, diagnostic improved, and treatment perfected are commendable, there are many uncertainties that still exist. Therefore, it is still premature to assume that pandemics will end soon.

The rational endeavour of international agencies and governments of all countries along with the behaviours of citizens of every country will greatly influence the course of the pandemic. There are many possible scenarios of the COVID-19 pandemic. One optimistic scenario is that the new generation COVID-19 vaccines are effective against all SARS-CoV-2 variants, including upcoming ones, and the vaccination drive is well coordinated to reach global control of the pandemic. The COVAX initiative is working to ensure vaccine equity as well as vaccine access, particularly to developing countries.
On the other hand, new and more contagious variants emerge repeatedly with the potential to escape vaccine immunity and only developed countries can afford to revaccinate their population with new adapted vaccines while less developed countries struggle with repeated waves and first-generation vaccines that are not well effective against new variants. In such a scenario, even high-income countries will have to face repeated outbreaks, and the time it takes to return to normalcy is much longer.

There are countries that are successful in keeping SARS-CoV-2 in check and countries where there are high levels of viral transmission will in time all probably reach a similar destination. Of course, the paths to reach a similar destination will be quite different because no country can remain permanently solitary from the rest of the world. Unfortunately, it is to be noted that countries working in isolation from each other and from global agencies will prolong the pandemic.

Modification of vaccines
If new mutant variants continue to appear, seasonal surges may become the norm in the future. Monitoring the epidemic and the emergence of new variants and accelerating the modification of vaccines to enhance their efficacy for emerging high-risk variants will be a challenge as time passes. At the same time, it is important to modify the behaviour of at-risk individuals. High-risk individuals such as people who are older than 65 years or people with co-morbidities such as diabetes, cancer, etc. should be motivated to change their behaviour. Behavioural modification such as mask-wearing, social distancing, and avoiding large gatherings, where the risk of transmission is high, will help protect most at-risk people. Besides, the global vaccination drive should be intensified.

Increased transmission of infection will heighten the likelihood of emergence of new and often more contagious and pathogenic variants anywhere in the world. COVID-19 has burdened intensive care units (ICUs) and ventilators. It is known that a social distancing measure reduces COVID-19 transmission, thus help reduce pressure on healthcare facilities. Hospitals may need to develop a greater capacity to respond to frequent surges with sufficient bed capacity, particularly ICUs and ventilators, and personnel.

(Prof. Lohani is the founder and academic director at Nobel College. lohanis@gmail.com)