When a virus replicates, it can change very slightly every time. This change is usually so small that it has almost no effect on how ill you become and how the virus spreads. Sometimes a change does cause a virus to behave differently, for example allowing it to spread more easily. RIVMNational Institute for Public Health and the Environment closely monitors changes in the coronavirus SARS-CoV-2 in the Netherlands and the consequences of those changes. 

It is known that viruses change frequently. There are already thousands of variants of the coronavirus SARS-CoV-2. RIVMNational Institute for Public Health and the Environment is conducting laboratory research to see which variants are present in the Netherlands and what that means for the spread of the virus in the Netherlands. This is known as pathogen surveillance. It is mainly important to know whether the variants that are circulating also have new characteristics that pose additional risks. For example if they are more easily transmitted, if they make people more ill, or if the virus variants do not respond as well to vaccination.

Variants in the Netherlands

There are many variants of the coronavirus SARS-CoV-2 circulating worldwide, and a number of those variants are now being monitored and investigated.  At the end of February, the WHO identified which are considered Variants of Concern and which are Variants of Interest. These variants are carefully monitored and mapped due to their (potential) high-risk characteristics and degree of spread.  RIVM is following the recommendations of the WHO in this respect. Through the national pathogen surveillance research, we are also working with laboratories in this country to monitor the coronavirus variants present in the Netherlands.  

Research on variants of the virus is also taking place in the Netherlands. At the end of 2020, RIVM started pathogen surveillance for the coronavirus, with random samples being examined on a weekly basis. That started with dozens of samples every week. As more and more laboratories join the efforts, RIVM now analyses about 1200 samples a week, about one thousand of those from the samples randomly selected in the context of pathogen surveillance.  The table below shows the pathogen surveillance results. 

Week number Number of  samples tested UK variant* South African variant* Brazilian variant P1* UK variant  with E484K mutation** Variants B.1.525 + E484K + F888L**
2020/49 77 1        
2020/50 118 1        
2020/51 190 1        
2020/52 238 5 1      
2020/53 204 9 1      
2021/1 334 32        
2021/2 270 43 2      
2021/3 536 125 3 1    
2021/4 786 194 14      
2021/5 774 238 16   1 5
2021/6 479 169 15      
Totaal   818 52 1 1 5

*Designated ‘variants of concern’ by the WHO; **Designated ‘variants of interest’ by the WHO

Pathogen surveillance data is updated weekly. Additional reports from those weeks may still be added up to and including week 4 of 2021 from the submissions provided by the laboratories participating in pathogen surveillance. In any case, the figures for the last two weeks are not yet complete. These weekly figures are updated retroactively. 

Difference in proteins

The main difference in the UK, South African and Brazilian variants and the B.1.525 variant seems to be the changes in the ‘spike protein’, the lines bristling out from the coronavirus. The proteins of these virus variants may be able to attach themselves to human cells more effectively. 

The UK variant

The UK variant of the virus was also found in the Netherlands in December 2020. It was detected during research in the RIVM laboratory. Since then, the UK variant has been gaining ground in the Netherlands. More and more people are becoming infected with this UK variant. 

In the meantime, it has become clear from research in the United Kingdom that people infected with the UK variant in that country became more seriously ill and died more frequently compared to the old variants. The reproduction number for the UK variant is estimated to be higher than that of the old variant. The R number represents the average number of people infected by someone who has COVID-19.

Children can also become infected with the UK variant, although less frequently than adults. This was shown by research in the municipality of Lansingerland. It seems that children are somewhat more likely to develop (mild) symptoms if they become infected with the UK variant. The symptoms are generally milder in children than in adults. Infected children can pass on the virus within a household and also at school. It is not yet clear whether primary school children also present a lower transmission risk for the virus variants compared to adults, as is the case for the ‘old’ variant. For now, there are no indications the vaccination will not be effective against the UK variant of the virus. This is being monitored closely all over the world.

Concerning change in UK variant (E484K) 

Viruses are constantly mutating. Sometimes a virus variant benefits from certain mutations, for example by spreading faster. Mutations of this kind give the virus variants an advantage over the old variants that are already circulating. Some mutations may emerge independently in different variants around the world. The UK previously reported the occurrence of a new mutation (E484K) in the spike protein in the UK variant.  Considered cause for concern, this E484K mutation has been detected previously in the variants from South Africa and Brazil. The immune response following vaccination or previous infection with the virus may possibly be less effective against variants with this E484K mutation. The mutation is also likely to affect how strongly the virus can bind to the cell receptors in our bodies. This E484K mutation has also been identified in the Netherlands during pathogen surveillance

The South African variant 

The South African variant was detected in the Netherlands in early January 2021. This variant of the virus, like the UK variant, also appears to be more contagious than the variant that we had so far in the Netherlands. How the virus responds to current vaccines is currently being investigated worldwide. So far, there is no reason to assume that the course of illness from the South Africa variant will be different or more severe than the old variant. 

The Brazilian variants

Two new variants of the coronavirus SARS-CoV-2 have been found in the Netherlands, both originating from Brazil. This involves the P1 variant and the P2 variant. 

The P1 variant of the coronavirus was found mainly in outbreaks in and around Manaus, the capital of the Brazilian state of Amazonas. It is not yet clear whether the course of illness is different for this variant. Among other mutations, the variant has three changes in the spike protein, the lines bristling out from the coronavirus, that are considered cause for concern. These three changes are almost identical to the changes in the South African variant. The immune response due to vaccination or due to previous infection with the virus may possibly be less effective against this variant. This is currently being investigated at the national and international levels.

The P2 variant occurs throughout Brazil. The immune response due to vaccination or due to previous infection with the virus may possibly be less effective against this variant. There is still much to learn about the course of illness from this variant as well. 

The B.1.525 variant

In the context of pathogen surveillance, a new coronavirus variant (B.1.525) was found in the Rotterdam-Rijnmond region and in the Limburg Noord region. This variant was first reported in Denmark. This variant also has the E484K mutation, along with another mutation (F888L) that is being monitored. Further investigation is now taking place in Denmark and the Netherlands

Prevent infection with variants

Regardless of which virus variant is involved: follow the measures. Get tested as soon as possible if you have any (mild) symptoms and strictly follow isolation and quarantine measures. If an infection with one of the variants is found, the Municipal Public Health Services (GGDs) will launch source and contact tracing.