(CNN) – Health officials said a new, slightly modified Delta version of the coronavirus is circulating in several countries, including the United Kingdom, the United States and India.
This strain, which has generated a great deal of global media attention, is called B.1.617.2.1 or AY.1, Delta Plus for short, a version of the delta variant first discovered in India in February.
This was first reported by Public Health England, a government health agency, on 11 June. But the first cases in the UK were sequenced on April 26, suggesting a variant may have been present and spreading in the spring.
The Indian government said it has sent the surrogate to the Global Data System with samples for genetic testing.
About 200 cases have been detected in 11 countries. Health experts are researching whether Delta Plus is more transmissible than other breeds such as alpha or delta variants, but it is too early to determine their effects.
Here’s what we know so far and the unanswered questions.
How is delta plus different from the delta variant?
All variants carry combinations of mutations. Delta plus has an additional mutation called K417N, which distinguishes it from the regular Delta variant. This mutation affects the skeletal protein, which is the part of the virus that attaches itself to the cells it infects.
Francois Ballou, director of the Institute of Genetics at University College London (UCL), said the K417N mutation is not entirely new: it has “emerged independently in several viral strains”.
He explained that the mutation was seen in a strain found in Qatar in March 2020, and is also found in the beta variant, which was first discovered in South Africa last fall. Media Science Center Wednesday.
“The mutation may contribute to immune escape, although its effect on transmissibility is not well defined,” he added.
All viruses constantly mutate. Some of these changes make viruses infect cells better or reproduce better, while others have little or even a detrimental effect on the virus.
So far, about 160 strains of the coronavirus have been sequenced globally, Ballox said.
On Wednesday, the Indian government said there were also “other delta-plus variants with other mutations,” adding that AY.1 was simply the most well-known.
Maria Van Kerkhove, WHO technical lead on COVID-19, added that the team was “looking at these specific mutations and what they mean in terms of transmission, in terms of severity and what is really important: what they mean in terms of our medical countermeasures.”
Meanwhile, the normal delta variant, also known as the B.1.617.2 strain, spread rapidly. It has been reported in dozens of countries and is 40% to 60% more transmissible than the alpha variant first identified in England, the European Center for Disease Prevention and Control (ECDC) said.
Is it more contagious or fatal?
According to the Indian government’s covid-19 genome sequence body, the delta plus variant shows several worrisome features, such as increased transmissibility, stronger binding to lung cell receptors, and a possible decrease in antibody response.
It is not yet clear what effect the mutation will have on the vaccine’s efficacy, but Julian Tang, professor of respiratory sciences at the University of Leicester, cautioned that it could give the variant “significant vaccine escape properties”.
Most coronavirus vaccines are designed to train the body to recognize the spike protein, or parts of it, where there is an extra delta-plus mutation.
However, there is still not enough evidence to determine anything conclusively and other experts have expressed caution. The Indian government said on Wednesday that the mutation’s role is in “immune escape, disease severity, increased transmissibility, etc.” He is under constant surveillance.
For now, experts are largely warning people and governments to remain vigilant and calm.
Besides the beta variant, none of the other strains carrying the K417N mutation have been “particularly successful so far,” Ballou said. “It has been found in many countries, but has been kept very low…There is no evidence that the strain is currently circulating in any country.”
WHO’s Van Kerkhove said the organization has been tracking Delta Plus to determine its transmissibility and severity.
Where was it found?
To date, Delta Plus has been reported in 11 countries, but the number of cases per country reflects only the samples that have been sequenced and more data is needed to determine the actual rate of prevalence.
The US has sequenced and confirmed the largest number of cases to date, with 83 as of June 16, according to Public Health England.
The UK is next, with 41 cases as of June 16. Downing Street confirmed Thursday that contact tracing, testing and isolation has been improved in areas where Delta Plus has been reported.
The first cases to be sequenced in the UK were people who had traveled or transited through Nepal and Turkey, according to Public Health England.
On Wednesday, the government said India was monitoring 40 cases. The cases were distributed in three states: Maharashtra, Kerala and Madhya Pradesh. On Tuesday, India’s health ministry classified it as a “variable of concern” and put all three states on alert.
The government said the number of cases remained low, but urged states with cases to “improve their public health response” by ramping up testing, screening and priority vaccination.
The rest of the cases were distributed among Canada, India, Japan, Nepal, Poland, Portugal, Russia, Switzerland and Turkey.