COVID19, arguably, has become endemic in India
Context:
- The infectious disease ‘outbreaks’ or ‘epidemics’ or ‘pandemics’ usually run their course and fade away one day. However, a small proportion of epidemics or pandemics transitions to the stage of endemicity, i.e., a level of transmission which is not considered to be a major concern by the public or health authorities.
- It has been more than 2 years of COVID- 19 but the numbers of daily new COVID- 19 cases in many countries are more than what had been reported at the peak of the national waves in those countries before the emergence of Omicron as a variant of concern.
- However, the severity of COVID- 19 infections is low and the burden of health services due to intensive care units and hospital admission even lower. COVID- 19 vaccination coverage is increasing and, in many countries, COVID-19 related restrictions have either been removed completely or relaxed to a large extent.
Background of COVID 19:
- COVID 19 is caused by Severe Acute Respiratory Syndrome Coronavirus, or SARS-CoV-2. This disease has caused millions of deaths worldwide. COVID-19 is an infectious disease that spreads from person to person. Coming to its structure, the outer layer of this virus is covered with spike-like proteins which surround it like a crown, thus named Coronavirus
- It is a zoonotic outbreak, meaning that it originated in animals- probably bats or pigs- and then jumped to humans by crossing the species barrier.
Virus Variants
- Viruses change constantly through mutation and this causes variants of the virus to emerge. Mutation is a part of the evolution of the virus. Many times, mutations emerge and disappear while others persist.
- SARS-Cov-2 virus is a single-stranded RNA virus. Mutations are changes in the genetic sequence of the RNA.
- A virus starts replicating when it enters a host cell or a susceptible body. The rate of replication increases with the spread of the infection increasing.
Classifications of the virus variants:
- Variant under Investigation: when the mutations happen and if there is any previous association with any other similar variant which is felt to have an impact on public health.
- Variant of Interest (VOI): This includes variants with specific genetic markers that have been associated with changes to receptor binding, decreased neutralisation by antibodies generated against vaccination/previous infection, lessened efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity.
- Variant of Concern (VOC): When there is evidence for increased transmissions through field and clinical investigations, a variant becomes a VOC.
- Variant of High Consequence: A variant that has clear evidence that prevention measures or medical countermeasures have drastically reduced effectiveness relative to previously circulating variants.
Is COVID endemic in India now?
After the third wave in January 2022, India saw the lowest number of daily new COVID-19 cases in March and April this year. However, since then, daily cases have spiked to around 18,000 a day. In fact, in the last two months every rise and fall in daily cases in India revives the discussion on whether COVID-19 continues to remain pandemic or has become endemic.
Differences between outbreak, epidemic, pandemic and endemic:
- Outbreaks are a localised spread while an epidemic is when a disease affects a large geographical area within a country or a few countries.
- A pandemic is when multiple countries in different regions of the world are affected. The severity of the disease has no or very limited linkage with this classification and a disease could be mild; but if it is widespread, it could be termed a pandemic.
- COVID-19 began as an outbreak in China- officially acknowledged in December 2019- and became epidemic afterwards when more countries were affected, and then, finally, was declared a pandemic in March 2020.
- One of the ways to differentiate between ‘pandemic’ and ‘endemic’ is the socio-economic impact. Pandemics are not merely health events but also encompass the social and economic implications of infections and diseases.
- For nearly two years, a large number of SARS-CoV-2 infections were happening in a short period of time — by a novel virus in a population which was completely immunologically naive — illnesses required hospitalisation and health facilities were overwhelmed. The infections, illnesses and hospitalisations understandably resulted in fear, panic and economic and social disruption.
- The interventions to halt the transmission of SARS-CoV-2, i.e., lockdowns, quarantines, national and international travel bans and school closure were equally unprecedented. There was a loss for many in terms of their sources of income after the ensuing social disruption and economic slowdown.
Future of the pandemic:
- New diseases usually do not disappear completely. 29months into the pandemic, there is consensus that SARS-CoV-2 will stay with humanity for long, possibly for years and even decades.
- The risk of the social and economic impacts due to COVID-19 is minimal and close to zero. So it is fair to conclude that while the health challenges of SARS-CoV-2 remain, the socio-economic impact is blunted. Hence COVID-19 pandemic in India may have moved to its endemic stage. However, that does not mean that the pandemic is over.
- In epidemiology and public health, context (local setting, infection rate and vaccine coverage) determines the disease spread. Therefore, in the ongoing pandemic, every country would reach an endemic stage at different points of time.
- Countries that had higher vaccination coverage and higher natural infection (such as India) are likely to reach this stage early. Countries with low natural infection and vaccination coverage (as in Africa) would reach an endemic stage a little later.
The acceptable risk factor:
- Since pandemics have a social impact, the decision on when a country has reached an endemic stage is also determined by societal perspective of ‘the acceptable risk’. There are a number of countries across the world where societies have returned to ‘normalcy mode’ even though the per million daily cases in many settings are higher than cases at the peak of earlier waves.
- In June-July 2022, around 30 deaths are being reported every day on average in people who tested COVID-19 whereas on an average, daily deaths in India from other factors include 120 deaths from pregnancy-related causes; 350 to 600 deaths in road accidents etc. But we have ‘accepted’ these risks, which are statistically graver than COVID-19. Hence the pandemic is now reduced to an endemic.
Way forward:
We must integrate COVID-19 interventions in general health services. It is time people do a self-assessment of their COVID-19 risk and undertake voluntary precautionary measures. COVID-19 vaccination should become part of the routine immunisation programme.
Conclusion :
Every effort should be made to avoid any death that is preventable. No society should be overly fixated over only one disease or health challenge. Clearly, COVID-19 is one of the many challenges and cannot continue to be the top and the only health priority.