Canadians worried about the British variant of the virus that causes COVID-19 can take comfort from a study in England which shows that infection rates have fallen by 67 per cent in the past month.
Interim monthly tracking figures released Thursday by researchers at London’s Imperial College found that the number of people in England who tested positive for COVID-19 had fallen by more than two-thirds from mid-January to Feb. 13. Infections dropped in every region and fell by 80 per cent in London.
The survey, known as the Real-time Assessment of Community Transmission, or REACT, is based on swab tests from around 160,000 people selected randomly each month across England. Early results from just over 85,000 tests found that the infection rate was 51 in 10,000 in February compared with 157 in January. The reproduction number, or R, has fallen below one in every region and dropped to a low of 0.61 in London. When the R number is below 1, the virus will eventually stop spreading.
“This is a better decline than many people would have hoped for,” said Steven Riley, professor of infectious disease dynamics at Imperial College. “Many scientists who look at this [data] regularly would have been more pessimistic about what we would see.” He added that the infection rate had dropped to the same level as last September.
The British variant, known as B1.1.7, was first detected in late November in Kent outside London. It spread quickly and now accounts for more than 80 per cent of all COVID-19 cases in the U.K. Studies have found that the variant is up to 70 per cent more transmissible and around 30 per cent deadlier than the original version of the virus.
The mutation has led to a surge in new cases which topped 60,000 across the U.K. on some days during December and January. The number of deaths and hospital admissions has also reached the highest levels since the pandemic began. However, the daily case total has fallen below 13,000 this week and hospital admissions have also slowed.
“I think it is reassuring that despite the greater transmissibility of that variant we are seeing this large reduction,” said Paul Elliott, director of the REACT program. He added that a national lockdown imposed shortly after Christmas was likely the main reason for the drop in infections. The data was “testimony to the lockdown and to the fact that we have reduced social contact, which is resulting in less transmission,” he said.
Dr. Riley said the survey results did not reflect the country’s mass-vaccination program which began in early December and picked up pace in January and February. Nearly 16 million people have been given at least one dose of vaccine so far, equalling roughly one quarter of the population.
The survey found that infections had declined in all age groups, including the elderly, who were first to receive jabs. “We have not observed a very strong drop in prevalence among older age groups, many of whom have been vaccinated,” Dr. Riley said, but added that the final results could yet reveal an impact.
Earlier this week, another tracking study found signs that the vaccination program was having an effect. Blood-testing results released by the Office for National Statistics (ONS) on Tuesday found that people over the age of 80 were more likely to have antibodies against the COVID-19 virus. That group was the first to be vaccinated and health officials said recently that around 90 per cent of them have been inoculated.
The ONS works in conjunction with researchers from several universities as well as public health officials who take blood samples from a random selection of people. The latest study found that 41 per cent of people 80 and over in England tested positive for antibodies. That was higher than any other age group and it was up from 26 per cent in a similar survey two weeks ago. The ONS said the finding was “most likely due to the high vaccination rate in this group.”
Dr. Elliot said that while the study findings were good news, he noted that the infection rate was still high across the U.K., at around one in 200, and that lockdown measures should be eased carefully. “We can take a lot of encouragement from the decline that we’re seeing,” he said. “But I would say we’re not out of the woods yet.”
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