2020 is closed year because of Covid, 2021 is the year of vaccines and 2022 is the year of reopening worldwide. 2023 will be the year of variant predictions. The first Covid variants that cause concern have been identified — from Alpha in the UK to Beta in South Africa — confusing the picture of the next course of the pandemic. Alpha is inherently better at transmitting, while Beta can evade pre-existing immunity to some extent. What will the long-term evolutionary model look like?
The picture becomes clearer in 2022, with the Omicron variant BA.1 causing major epidemics. This leads to accumulation of immunity in populations, followed by diminished transmission, only when a new sub-variant, BA.2, emerges, that immunity is less effective. . This is followed by major epidemics and the cycle begins again, with another in mid-2022 when BA.5 emerges.
If this evolutionary trajectory continues, we should see this cyclic pattern in 2023 and beyond. It’s a similar dynamic to the seasonal coronaviruses that have plagued epidemics for decades. A 2021 study by researchers at Fred Hutchinson Cancer Research Center discovered that the coronavirus gradually evolved over time, so previous immunity was less effective.
This will create challenges for Covid-19 vaccination campaigns; if the virus evolves this way, ideally we should update the vaccine, so the viral protein in the vaccine closely resembles the protein our body would encounter in the variants stored onion. But updating vaccines takes time. For the flu, World Health Organization makes recommendations twice a year on what variations should be in that season’s vaccines in each hemisphere. Due to production and distribution timelines, decisions on winter vaccines are made six months earlier. That makes vaccine selection a matter of prediction.
When it comes to selecting flu vaccines, the teams use a variety of data, from the growth rates of circulating variants in genomic data to tests for their immune properties. Another complication is variation in what different populations have previously been exposed to. Some countries may have more preexisting immunity than others, and therefore variants that can evade this immunity have more advantages. We often see different influenza viruses dominating in different continents and countries.
In 2023, this prediction challenge will also become routine for Covid. Some countries have approved photo adjusted for sub-variant Omicron BA.1. But how well will these new vaccines fit into variants circulating further afield? Decisions for the winter of 2023–24 in the northern hemisphere will likely have to be made as early as 2023. Making the right choices can have a major impact on the size and severity of the waves. Covid in the future. For the H3N2 influenza subtype, which tends to cause the largest seasonal outbreaks, the challenges surrounding the selection and production of vaccines that are effective against symptomatic disease are: usually less than 50 percent.
Farther in the future, there is hope for progress on “universal” coronavirus vaccine, will be highly effective for a wide range of variants. But the history of developing other universal vaccines, such as the flu vaccine, shows that success is not entirely guaranteed. Therefore, next year will be the beginning of the long game of cat and mouse, given vaccine updates against an evolving virus. Addressing this prediction question—and rolling out the resulting vaccines—will be one of the major health challenges of 2023.
