The highly contagious variant of COVID-19 which originated in India, now named the Delta variant by the World Health Organisation, is officially the dominant strain in Britain and is spreading rapidly.

On Thursday, Public Health England announced that the number of laboratory-confirmed Delta coronavirus cases had risen by 79 percent over the last week to 12,431 and overtaken the number of cases of the Kent, or Alpha, variant.

The government has gone into overdrive to portray the virus as under control, claiming that its vaccine rollout means everything must still be allowed to return to normal. But not only is the Delta variant on the rampage, on Thursday the government admitted that a Nepalese strain of the Delta variant which has acquired a new mutation is present in the UK.

Delta was first detected in Britain on April 1, but the government did not make its existence public until April 15, of a piece with its overriding aim of doing nothing to prevent a further opening of the economy.

This reckless reopening, ongoing for months and set to be completed in less than three weeks on June 21, has allowed a comparatively successful vaccination rollout to be derailed by the spread of a highly contagious variant. On May 17, most of the economy was reopened, including cafes, restaurants, gyms, cinemas and most non-essential sectors.

Cases of Delta infections and deaths have been steadily increasing from a base of just a few infections. For the last seven days there have been at least 3,000 cases daily. On Friday May 28 this reached 4,000 cases and by Thursday had reached nearly 6,000 daily cases (5,774)—the highest number since the UK was still under a limited national lockdown in late March. On Friday, new cases reached a new high of 6,238. Deaths from Covid have also begun to rise again from the zero deaths reported on Monday—a figure the media insisted justified ending remaining lockdown restrictions without delay. Twelve deaths were reported on Wednesday, 18 on Thursday and 11 Friday.

More dramatically at this point, coronavirus cases are on the increase in all but three regions of Britain, with the R (reproduction) rate rising to between 1 and 1.2—up from between 1 and 1.1 last week. Delta cases are rising at among their fastest rate in London, with the Evening Standard reporting Friday that more than two thirds of Covid-19 cases in the capital are believed to be the Delta strain.

According to the Office for National Statistics (ONS), there was a 76.5 percent surge in coronavirus cases nationally in the week to May 29. Announcing its weekly survey yesterday, the ONS said that one in 640 people (86,000) in private households in England had COVID-19 in the week to May 29—up from one in 1,120 (48,500) in the previous week.

Cases appear to be rising even faster among Scotland’s 5 million population. On Thursday, Scottish National Party First Minister Nicola Sturgeon announced another 992 people had tested positive—the highest daily figure since February 17—with new Covid cases more than tripling in the last month.

All the evidence shows that the Delta variant is, as feared, far more transmissible than the Alpha (Kent) variant discovered last year, which quickly became dominant in the UK and spread rapidly around the globe.

On Thursday, Neil Ferguson, a leading epidemiologist at Imperial College London and previously a member of the government’s Scientific Advisory Group for Emergencies (SAGE), warned on BBC Radio 4’s Today programme that Delta is “between about 30 percent and maybe even up to 100 percent more transmissible.” Data was pointing in a “negative direction” and “The best estimate at the moment is this variant may be 60 percent more transmissible than the Alpha [Kent] variant.”

Ferguson is derided in the right-wing media as “Professor Lockdown”. His warnings that the government’s declared herd immunity agenda could result in up to 500,000 deaths were central in forcing the first lockdown last year.

If it transpires that the transmissibility of Delta is in the order of 60 percent higher, this could have a catastrophic impact under conditions in which only 50 percent of the population is fully vaccinated and virtually all children and millions of adults under 40 totally unvaccinated. According to SAGE modelling, a strain of COVID that is 50 percent or more transmissible than the Kent strain will lead to between 10,000 and 20,000 hospital admissions per day by the summer and 1,000 deaths daily by August. SAGE predicted that such numbers would rapidly overwhelm the National Health Service. Ten thousand hospitalisations a day is more than double the UK peak of hospitalisations in the pandemic so far.

In its technical briefing issued Thursday, Public Health England estimated that the Delta variant is as much as 2.5 times more likely to lead to hospitalisations than the Alpha (Kent) variant.

This could have further terrible consequences under conditions in which an estimated 1 million people in private households in the UK reported experiencing “long Covid” in the four weeks to May 2. Of these, over a third (376,000) contracted the virus, or thought they were first infected, over a year ago.

Of extreme concern, on Thursday the Francis Crick Institute and the UCLH Biomedical Research Centre published a study noting that the current generation of vaccines may be on the point of being outstripped by the new variants. Those who have received two doses of the Pfizer vaccine had levels of neutralising antibodies that were more than five times lower against the Delta variant when compared to the original strain. For those who had only received one dose, antibody levels against Delta were even lower. Moreover, the levels of antibodies were lower with increasing age and those levels dropped over time.

One Pfizer jab resulted in 79 percent of people having a quantifiable neutralising antibody response against the original strain. Against the Alpha (Kent) strain this fell to 50 percent, to 32 percent for the Delta strain and as low as 25 percent for the Beta (South African) strain.

Throughout the pandemic, the government, aided by the Labour Party and the trade unions, have insisted that schools were not vectors of transmission and that children and educators should be in classrooms so parents can go to work and generate profits for the corporations.

Yet again these lies are being refuted. Public Health England data this week covering April 26 to May 30 showed 140 cases of the Delta variant already in schools. At the end of April there were just three Delta clusters in primary and secondary schools, but by the end of May this had shot up to 39 clusters. With a total of 97 outbreaks in schools with at least one of the variants detected, this equates to around one in 250 schools nationally.

Professor Christina Pagel, director of the clinical operational research unit at University College London, told the Guardian the figures were evidence that schools were now “a major source” of transmission.

Just a few days after Conservative Prime Minister Boris Johnson said he saw no reason not to plough on to remove “all legal limits on social contact” on June 21, the government was forced to take Portugal off its “green list” of holiday destinations due partly to what Transport Secretary Grant Shapps said was the discovery of a “Nepal mutation of the so-called Indian variant”. Shapps said that at this stage it could not be ruled out that the mutation is “vaccine defeating”.

On Thursday, it was announced that all UK holidaymakers currently in Portugal had to return to the UK by Tuesday and undergo 10 days of quarantining.

A small number of Delta variants, including the Nepalese, have an extra mutation, K417N, of which around 90 cases have been identified worldwide—12 in Portugal, 36 in the UK, 12 in the US and four in India. According to virus sequencing by Public Health England, there may in fact be 43 cases in Britain.

Despite the emerging public health disaster, the government still insists that its June 21 “Liberation Day” must go ahead, only offering the “advice” that people work from home if possible.