10% of Dutch coronavirus infections last week tied to B117 mutation

Some 38,776 people in the Netherlands tested positive for the SARS-CoV-2 coronavirus for the week ending Tuesday morning, the RIVM said in its weekly analysis. It said that despite a near 22 percent drop in infections, and a further decrease in the rate of people testing positive, the agency was increasingly concerned about the rise of the B117 coronavirus mutation.

The variant, which first surfaced in the United Kingdom, was believed to have infected 10 percent of those who tested positive in the Netherlands last week. "That is double compared to the week before. It is expected that this will rise to at least half of all new infections by mid-February," the RIVM said in a statement.

The B117 variant pushed the basic reproduction (R) number in the Netherlands up to 0.98, meaning that 100 contagious people will infect 98 others. "We are dealing with two virus variants that seem to spread at different rates in the Netherlands. As a result, there are actually two separate coronavirus epidemics. An epidemic with the 'old' variant, in which the number of infections is falling, and an epidemic with the British variant, in which the number of infections is increasing," the RIVM stated.

The fear of a new wave of coronavirus infections caused by the B117 mutation was likely pushing the Dutch Cabinet to impose new coronavirus restrictions on a country already under lockdown for over a month. The new restrictions could include a curfew and a stricter policy about receiving guests at home. Outgoing Health Minister Hugo de Jonge was expected to announce the restrictions on Wednesday.

Of all those tested by public health service GGD last week, 11.0 percent of people tested positive for the coronavirus infection. However, that figure was corrected to 11.7 percent by excluding the thousands of residents of Lansingerland who were tested in a study to determine the spread of B117. Not including the Lansingerland study, over 293 thousand people were tested by the GGD last week, down about ten percent from the week before.

Hospitalizations and deaths linked to Covid-19 were also down last week. Some 1,348 people were admitted into regular care for treatment of the disease, down 17 percent. There was also a 16 percent drop in intensive care admissions to 252. The RIVM was also notified of 18 percent fewer deaths caused by Covid-19, which totaled 608.

The RIVM stressed that the B117 variant does not make people more sick, nor should it affect the percentage of people who will require hospitalization for Covid-19. "The difference is that this variant is more contagious. If social contact between people and compliance with the measures remains the same as now, this will therefore lead to a much higher number of infections. Due to more infections with the 'new' variant, the number of hospital admissions and deaths will also be higher than we currently see," the RIVM stated.

"This will mean that the pressure on healthcare will increase again instead of decrease."

To date, 921,580 people have tested positive for SARS-CoV-2 in the Netherlands, including 13,162 who were known to have died from Covid-19. Of those infected, 35,187 were treated in the regular care department of a hospital, and 7,481 required intensive care.