In the early days of COVID-19, it was too difficult to get infected for the second time. And two years on, it is not the same now. Many people who had the disease earlier are affected it for the second or the third time. Reports suggest that it is mostly due to three key reasons: (a) the waning of vaccine immunity; (b) omicron variant; and (c) the sheer number game.

Waning of Vaccine Immunity

As the COVID-19 vaccine weakens over time, the risk of re-infection of the COVID-19 increases. The World Health Organization (WHO) has also indicated that this can happen, which is why we take more than one vaccine in order to get maximum protection against COVID-19 and its variants.

“As we enter the 3rd year of the pandemic, we expect to see some waning over time. It depends on the type of vaccines you have taken, the number of doses and also age and underlying conditions,” WHO’s Maria Van Kerkhove said.

Omicron Variants

Omicron variants, both BA.1 and BA.2, are biologically very different from previous strains. These differences provide an excellent opportunity to transcend the body’s early defenses based on the manifestation of previous COVID-19 infections. A BBC report said, “And so the rates of reinfection have been about 10 times higher this year compared with rates seen earlier in the pandemic.“

The Sheer Number Game

Part of it is the numbers game. Many of us have already become infected at some point, and the rising rate of new infections is a second bout, the report too points out. However, experts point out that even if you get a positive test a second time it is unlikely to cause a serious infection. Immunology expert Prof. Eleanor Riley said in cases like this, “it means there is virus in your nose and throat.“

WHO has penned down the three possible ways the COVID-19 virus and its variants will evolve in the future and also explained the key strategies that, if implemented in 2022, would allow the world to end the emergency phase of the pandemic. WHO Director-General Tedros Adhanom Ghebreyesus said in a media briefing that the virus will keep evolving, however, the severity will be far lesser when all persons have improved their own immunity and through proper vaccination.

Possible Ways COVID-19 Virus Will Evolve

The WHO Chief divided the possible ways the virus and its variants will evolve in the upcoming days into three categories:

• Base-case scenario
• Best-case scenario
• Worst-case scenario

Base-Case Scenario

According to the WHO chief, the base-case scenario is the severity of the virus. According to Tetros, the weaker the immune system, the more severe the outbreak with occasional spikes in the spread of the virus and its variants. In this scenario, countries may feel the need for booster doses, especially for those at high risk. In this scenario, the COVID-19 virus falls into a seasonal form, peaking only in the colder months, which is similar to the flu.

Best-Case Scenario

The second is a best-case scenario. Of these, future variants of COVID-19 will be significantly less severe, resulting in a lower number of infections and fewer hospital admissions. Without the need for boosting in the future, people will be protected from all serious diseases for a long time to come. No changes need to be made to existing antiviral vaccines.

Worst-Case Scenario

In the worst-case scenario, WHO chief said that the world will see the emergence of some of the deadliest, most contagious and deadly virus variants. Under these circumstances, most vaccines against COVID-19 and its variants will be less effective and the immune system will rapidly decline from serious illness and death. Explaining what would happen in this case, Tetros said that the need for an updated version of the current COVID-19 vaccine and the widespread campaign for booster shots for all people to handle this situation.

Needs to be Done

The WHO chief said that everything can be managed with well-planned strategies. These include the following steps:

• All countries should continue or increase virus surveillance capabilities to allow early warning signs of significant changes in the virus and its variants.
• WHO has called for an improvement in the process of diagnosing patients with long COVID-19 disease. In this way, authorities can help monitor and mitigate long-term disability once the pandemic is over.
• Countries also must continue to do diagnostic testing for COVID-19, which helps identify individual cases and guide community-level decision making.
• WHO also urged the countries to compulsory track the evolution of the COVID-19 and its variants’ evolution within animal populations.

Meanwhile, 1,225 new COVID-19 cases have been reported in India on April 1st, bringing the total number of cases in the country to 4,30,25,775, while the number of active cases has dropped to 13,672. This comes at a time when global COVID-19 cases have been on the rise over the past few days, primarily due to severe mutations in its spike protein due to the highly contagious BA.2 Omicron variant, which easily affects the strain to infect fully vaccinated individuals.

Source: Medindia