- It is changing constantly. Since the beginning of the pandemic.
2. Total no. of variant till 2023:-omicron and subvariants, Delta, Delta AY 4.2, Beta (Beta may have been more likely than other variants to lead to hospitalization and death.) , Alpha,
3. Severity:-Studies have suggested the Alpha was more likely to land infected people in the hospital and was deadlier than the original virus.
4. contagious:-Omicron’s subvariants are considered the most transmissible strain of the virus so far. The original strain of Omicron was more transmissible than Delta and others.
5. vaccinations :- Pfizer, Moderna, and Johnson & Johnson all said their vaccines were effective in preventing severe disease and hospitalization in Alpha cases and others.
(This article was medically reviewed by Yale School of Public Health epidemiologist Nathan Grubaugh, PhD).