The coronavirus omicron variant or B.1.1.529 was first detected in 2021. Since then, it has the globe, vanquishing other variants such as Delta. It began to branch into several subvariants: BA.2 and BA.5, which later became the dominant strains. Omicron subvariants B.Q.1 and B.Q.1.1 later became the dominant form of the virus in the U.S.A. Other subvariants such as XBB, BF.7 and BA.5 are still out there. WHO mentions the Omicron variant of Coronavirus as a variant of concern. It spreads more than any previous variants, and the associated risk related to this variant is also very high.
Subvariants of Omicron (B.1.1.529):
After the B.1.1.529 variant emerged in 2021, many subvariants of were observed. As the virus was circulating at an intense level, they are considered variants of concern. WHO-approved COVID-19 vaccination protects against severe illness or death, but spikes in cases are being observed globally.
It rapidly evolved into multiple subvariants. One such is a subvariant, BF.7. It has been recognised as the primary variant spreading COVID infections in China.
BF.7 is short for BA.220.127.116.11, a sub-variation of the B.1.1.529 variant BA.5. Reports from China indicate that it can have the most potent infection ability and shortest incubation period among other variants. The very high transmission rate and asymptomatic carriers cause significant difficulty in controlling the epidemic in China.
Symptoms of omicron (B.1.1.529) subvariants:
Typical symptoms of the B.1.1.529 and it’s subvariants are:
- Sore throat
- Runny nose
- Nasal congestion
- Muscle pain
Unlike the Delta variant, which affected the lungs, B.1.1.529 and its subvariants cause more upper respiratory symptoms. Symptoms include sore throat, congestion, and changes in taste and smell. The symptoms are very similar to any flu virus. Therefore, doctors urge people to get tested for flu-like or cold symptoms.
Vaccine protection against the omicron subvariants:
In August 2022, the FDA authorised a new version of the Covid booster. This booster dose targets the spike protein of BA.4 and BA.5 subvariants. Also, it targets the original strain of the virus, discovered in Wuhan, China, in 2019. By December, the booster has been authorised for anyone ages 6 months and older. People who were up to date with their vaccination showed mild illness during the first omicron(B.1.1.529) wave. Centre for Disease Control (CDC) research also found that the new boosters are more effective than the original booster, especially for people older than 65.
Subvariant incubation period:
It takes time for an infected person to develop symptoms after being exposed to the sub-variant or Coronavirus. It varies from 3-4 days to a week. The incubation period could be longer or shorter depending on variables such as age, underlying health problems and vaccination status.
How long do subvariant Symptoms last?
Symptoms appear milder and shorter in vaccinated people compared to the non-vaccinated population. Hospital stays are also typically shorter for vaccinated people with the subvariants.
How long one is contagious with a subvariant?
A person is generally contagious from two days before symptoms begin and three days after. After that, the immune system starts working, and contagiousness goes down. The CDC’s recommendation is to be in isolation during the first 5 days to avoid spreading the virus to others.
Omicron BF.7 strain:
BF.7 variant is a mutation of the Omicron and has the highest transmissibility amongst all Covid variants. The R0 value of this mutant is approximately 10-18.6, meaning one infected individual can infect 10-18.6 people around them.
BF. 7’s mutations:
BF.7 has a distinct mutation in the spike protein of SARS-CoV-2 called R346T. This mutation is also seen in variant BA.5, the parent of BF.7. It gives the variant the ability to evade vaccine or previous infection-generated antibodies.
Symptoms of Omicron subvariant BF.7:
The symptoms of subvariant BF.7 are very similar to other B.1.1.529 subvariants. Typical symptoms include
- Runny nose
- Sore throat
Precautions against BF.7 strain:
It is essential to follow COVID guidelines as Christmas and New Year’s celebrations are around the corner. The most crucial precaution should be getting the vaccination and booster shots. One should wash hands frequently, adhere to social distancing norms and wear a mask.
Omicron BF.7 strain has wreaked havoc in China and has already been found in India. Till now, 4 cases have already been detected in India. The variant is a new mutation of the Coronavirus. It is swift to transfer, and the incubation period is concise. It is expected that 60% of the Chinese population will be infected by the BF.7 variant within the next three months.
BF.7 around the world:
The variant has been found in countries like India, the United States, the United Kingdom, Belgium, Germany, France and Denmark.
Despite BF.7’s immune-evasive properties and panic signs in China, the variant is relatively steady in other places. Therefore, it isn’t easy to understand why the situation is different in China. BF. 7’s high R0 value could be due to low immunity, less exposure to the previous infection due to China’s Zero Covid Policy or insufficient vaccination.
An evolving virus:
Since the covid 19 outbreak and the emergence of SARS-CoV-2 almost 3 years ago, the virus has evolved and acquired rapid and unexpected mutations.
Though the emergence of BF.7 and other new variants is the reason for concern till now, vaccination is the best weapon to fight against COVID-19. And the recent approval by the UK drugs regulator of bivalent boosters, which target Omicron alongside the original strain of SARS-CoV-2, is very promising.
1. Araf, Y., Akter, F., Tang, Y.-D., Fatemi, R., Parvez, M. S. A., Zheng, C., & Hossain, M. G. (2022). variant of SARS-CoV-2: Genomics, transmissibility, and responses to current COVID-19 vaccines. Journal of Medical Virology, 94(5), 1825–1832. https://doi.org/10.1002/jmv.27588
2. CDC. (2022, August 31). Variants of the virus. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/variants/index.html
3. Coronavirus. (n.d.). variant: What we know so far about this COVID-19 strain. Ucdavis.edu. Retrieved December 23, 2022, from https://health.ucdavis.edu/coronavirus/covid-19-information/variant
4. Edwards, E., Kopf, M., Miller, S. G., Lewis, R., Lovelace, B., Jr, & Silva, D. (2021, December 21). subvariant symptoms: How quickly do symptoms appear? NBC News. https://www.nbcnews.com/health/health-news/symptoms-covid-what-to-know-rcna9469
5. Katella, K. (2022, December 9). Yale Medicine. https://www.yalemedicine.org/news/5-things-to-know
6. SARS-CoV-2 viral mutations: Impact on COVID-19 tests. (n.d.). U.S. Food and Drug Administration; FDA. Retrieved December 23, 2022, from https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/sars-cov-2-viral-mutations-impact-covid-19-tests
7. Update on Covid (n.d.). Who.int. Retrieved December 23, 2022, from https://www.who.int/news/item/28-11-2021-update-on
8. What we know about the Cvoid variant. (n.d.). Unicef.org. Retrieved December 23, 2022, from https://www.unicef.org/coronavirus/what-we-know-about-variant
9. Wikipedia contributors. (2022, December 21). SARS-CoV-2 variant. Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/w/index.php?title=SARS-CoV-2-variant&oldid=1128752044