The more transmissible coronavirus strain B1617 has spread to nearly 50 countries and regions around the world. The World Health Organization urges more research to understand the severity of the strain and its propensity to cause reinfection.
B1617 first appeared in India in October last year and is believed to be one of the reasons for the explosive growth of confirmed cases of coronary disease in India.
The WHO said on Tuesday (May 11) that more than 4,500 coronavirus samples uploaded to an open database have been tested for the B1617 strain. These samples come from 44 countries and cover the six major WHO regions, namely Africa, America, Southeast Asia, Europe, Eastern Mediterranean, and Western Pacific.
The WHO also revealed in its weekly report on the coronavirus epidemic that five other countries have notified the WHO that the B1617 strain has been detected. The report says that outside of India, the UK has reported the most cases of B1617.
Three variant strains derived from B1617
There are currently three variant strains derived from the B1617 strain, namely B16171, B16172 and B16173. The WHO said that the three derived variant strains may have important differences, but the available evidence is too limited to define their characteristics. The organization is temporarily unable to determine whether this will affect the effectiveness of vaccines or treatments.
Preliminary analysis shows that the reproduction rate of B16171 and B16172 is much higher than that of other variant strains circulating in India, indicating that B16171 and B16172 may have a stronger transmission ability. The WHO said that these two variant strains quickly emerged in multiple countries.
However, the WHO also said that so far, only 0.1% of confirmed cases in India have been genetically sequenced and uploaded to the Global Influenza Shared Database (GISAID) to identify which variant strain they belong to. As of the end of April, B16171 and B16172 accounted for 21% and 7% of all sequencing samples in India, respectively.
The World Health Organization just listed the B1617 strain as the fourth “concerned” type of coronary disease in the world on Monday. The first three are B117, which was first discovered in the UK, B1351, which was discovered in South Africa, and P1, which was discovered in Brazil. They are considered more dangerous than the original virus because they are more transmissible and lethal, and may resist the protective effects of certain vaccines.
B1617 is also called “dual variant” because its spike protein has two mutations. The rapid deterioration of the coronavirus epidemic in India is believed to be inseparable from B1617.
At the beginning of March this year, the number of daily confirmed cases in India had dropped to less than 20,000. Unexpectedly, the number of cases suddenly increased afterwards, with more than 300,000 cases per day lasting for nearly three weeks.
India adds another 350,000 confirmed cases
India added nearly 350,000 confirmed cases and 4,205 deaths on Wednesday, bringing the cumulative number of confirmed cases to over 23 million and the cumulative number of deaths to over 250,000.
The WHO said that in addition to the raging variant of the virus, “several religious and political gatherings” and the people’s non-compliance with social distancing measures have also made this wave of epidemic in India out of control. However, “the exact impact of these factors on the intensification of the epidemic in India is unclear.” In addition, the WHO reported that preliminary laboratory studies have shown that the ability of antibodies to neutralize B1617 is low, which means that the effectiveness of certain vaccines may be weakened. But the report also said that more relevant research is necessary.