The Union health ministry on Tuesday said that 795 people in India have been infected with the coronavirus variants, first detected in the United Kingdom, South Africa and Brazil, NDTV reported.

Till March 18, as many as 400 people in India had contracted the three mutant versions, which have now spread to dozens of countries. The nearly 50% rise in cases of new strains came as many states in India report a sharp surge in daily infections. There have been fears that new variants of the virus might be the reason for the uptick in cases.

Of the 395 mutant virus cases reported since last week, at least 326 are from Punjab and have been identified as the UK variant, according to NDTV.

Earlier in the day, Punjab Chief Minister Amarinder Singh had also flagged that 81% of the 401 samples sent by the state for genome sequencing tested positive for the UK variant. The chief minister urged Prime Minister Narendra Modi to widen the country’s immunisation drive and immediately begin vaccinating the younger population.

Hours later on Tuesday, the Centre announced that all those above 45 years can be vaccinated from April 1. After inoculating healthcare and all other frontline workers in the first phase, the government began vaccinating its older population, with people above 60, and those who are 45 or more and suffering from certain medical conditions, eligible for the vaccinations.

The British variant is responsible for a chunk of new infections in the United States and Europe. German Chancellor Angela Merkel on Tuesday said the UK variant “is much deadlier, much more infectious” and had a longer effect, AFP reported.

Known as the B.1.1.7 variant, it has spread to more than 50 countries. It was first detected in September and has 23 mutations in its genetic code a relatively high number of changes. Experts say it appears to be 40%-70% more transmissible than previously dominant variants.

India reported 40,715 new coronavirus cases in the past 24 hours, with Maharashtra contributing more than 60% of the total. Deaths rose by 199 to 160,166. The active cases in the country jumped for a 13th straight day and stood at over 3.45 lakh.