At that time, it was called the L strain.
It didnt take long for COVID to start mutating enough that variants of the original virus emerged.
Illustration by Laura Porter for Verywell Health
Strains vs. Variants
Strains and variantsare different.
Illustration by Laura Porter for Verywell Health
All strains are variants, but not all variants are new strains.
Heres a look at the most notablestrainsand variants of the COVID virus throughout the pandemic.
The first highly publicized variantB.1.1.7, then called Alphashowed up in the United Kingdom in September 2020.
Alpha caused a surge of COVID infections around the world, starting before any vaccines were available.
This variant was more deadly than the original strain of the COVID virus.
The three major vaccines against COVIDPfizer, Moderna, and J&Jall were effective against Alpha.
It quickly spread to other countries.
The three main vaccines offered in the U.S.Pfizer, Moderna, and J&Jwere effective against Beta.
Some research suggests that some variants might be more likely to lead to long COVID symptoms than others.
For example,infection with Omicronmight be less likely to lead to long COVID than infection with earlier variants.
Gamma was not responsible for many COVID cases in the U.S. By the fall, experts considered it one of the variants to monitor.
Similarly, there were concerns that antibody treatments for COVID would not be as effective.
B.1.617.1 (Kappa)
B.1.617.1 was dubbed the Kappa variant.
It was first detected in India in the fall of 2020.
It spread to other countries and the WHO considered it a Variant Under Investigation.
However, global public health experts did not consider it to be a major variant of concern.
As of fall 2021, the WHO deemed it a variant to monitor.
Most of the reported cases of COVID linked to the Kappa variant were inIndia.
Researchsuggested that vaccines were at least somewhat effective against Kappa.
C.37 (Lambda)
C.37 was called the Lambda variant.
B.1.525 (Eta)
B.1.525, theEtavariant, was firstdetectedin the UK and Nigeria in December 2020.
When it did not spread further, the WHO dropped the variant of interest designation.
Multiple studies showed that the Delta variant caused more severe disease and hospitalizations in unvaccinated people than other variants.
Although the U.S. had launched a COVID vaccination campaign, the Delta variant was able to evade vaccine-induced immunity.
The surges prompted health authorities around the world to urge people to get a booster vaccine.
The most common symptoms of the Delta variant wereheadache, sore throat, runny nose, and fever.
Delta Plus
Delta AY.4.2 was an offshoot of the Delta variantnot a variant on its own.
Delta AY.4.2 had two mutations on its spike protein, which helped the virus to enter and infect cells.
The mutations appeared to make it 10%20% more transmissible.
Omicron BA.1 and BA.2
Omicron subvariant BA.1 closely followed B.1.1.529.
The WHO said that BA.2 had a growth advantage over the original Omicron variant.
Omicron BA.2 started spreading more in the northeastern U.S. around March 2022.
The most common symptoms of BA.1 and BA.2 were similar to those of B.1.1.529.
Vaccine makersstarted working onupdated versions of their vaccinesand more than one booster was suggested for most people.
Omicron BA.4 and BA.5
Omicron BA.4 and BA.5 showed up in the U.S. around May 2022.
B.1.640.2
In October 2021,researchers in Francefound a new COVID variant deemedB.1.640.2.
The most common symptoms of B.1.640.2 weresore throat, cough, and a hoarse voice.
As of August 2023, no variants are listed as variants of concern.
As of the end of August 2023, the WHO has listed 3 Omicron variants as variants of interest.
There are also several other Omicron variants under monitoring.
Again,no variants had been deemed variants of concern(VOC).
Omicron XBB and XBB.1
XBB variants of Omicron began circulating in late summer 2022.
It also did appear to be more resistant to antibodies from a previous infection or a vaccine.
The symptoms ofXBB variants were similar to other Omicron variantsmainly, cough and congestion.
Unlike the earliest COVID variants, XBB wasnt as likely to cause loss of taste and smell.
Omicrons newer variants have been broken down even more as new mutations have cropped up.
XBB.1.5 has some mutationsincluding EG.5, FL.1.5.1, XBB.1.16.6, and FE.1that are being monitored under this umbrella.
One exception is that they may have a higher impact on immunity.
In July 2023, the WHOconsidered it a variant under monitoring.
Current COVID tests appear to be capable of picking up BA.2.86.
However, a study from last September had suggested that antiviral treatments like Paxlovid did seem effective against BA.2.75.
Like EG.5, FL.1.5.1 appeared to have a mutation that made it spread more easily.
The fall also brought another XBB variant,HV.1, to the forefront.
By November, accounted for about one-quarter of COVID infections in the U.S.
It overtook EG.5, which had been dominant over the summer.
On December 19, the WHO announced it was classifying JN.1 as a variant of interest separate from BA.2.86.
It also didn’t appear to be causing more severe illness compared to previous variants.
KP.3, KP.3.1.1
More FLiRT variants,KP.3and KP.3.1.1 began appearing in early summer.
Experts haven’t seen any significant differences in the KP.3 variants in terms of causing new or worse symptoms.
KP.2.3 was slightly ahead at 14.2%.
LB.1
The newest COVID variant on the scene has been dubbed LB.1.
It’s an emerging subvariant similar to the FLiRT variants but withanother mutation.
It’s still possible that LB.
1 could overtake KP.2 and KP.3’s summer dominance.
But some early evidence from researchers in Japan suggested that it could be better at evading immunity.
New variants of concern will be added according to reports by the WHO and the CDC.
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