Delta variant: How dangerous is it and do vaccines work?

It is the nature of viruses to mutate. This means that, while they try to make a copy of themselves when they get into one’s body through a receptor cell like that in the respiratory system, they may make a mistake.

This mistake is called a mutant, or a variant. There are two classes of variants –variants of concern (VoC) and variants of interest.

The World Health Organization has named only four variants of concern: Alpha, Beta, Gamma and Delta whose origins are Britain, South Africa, Brazil and India respectively. Kenya has identified all the variants in the country but the Delta variant, which was first identified in Kisumu, has been the talk of town lately. Why is that?

Healthy Nation sought answers from two infectious disease experts, Prof Walter Jaoko and Prof Matilu Mwau.

What is the delta variant?

It is thought to be the main driver of the surge in cases in India and has now spread to about 80 countries including Kenya. It is a mutation of the coronavirus that has three substitutions in the spike protein. Because of these three substitutions, it now has an increased secondary attack rate and that means that one can be re-infected with Covid-19. It is more transmissible. It is also reasonable to assume that it is more difficult for vaccines to neutralise their spike proteins.

What does it do to one’s body?

When viruses mutate, they can either be less transmissible, some have no harm while others can be more transmissible. When the Delta variant gets into your body, it attaches itself to your cells easily compared to all the existing variants of concern or the original one. Its ability to attach to cells more easily is the reason for its high rate of transmission.

What happens when it attaches itself to a cell in one’s body?

For one to be affected with the coronavirus, the spike protein attaches itself to a cell and then makes its way into the cell. Once it is inside the cell, it starts to replicate and therefore causes Covid-19 disease infection.

Does this variant cause severity of disease

The fact that it can be easily transmitted does not mean that it also makes one very sick to the point of hospitalisation when it gets into their body. There is no evidence for that yet. What has been seen now in preliminary findings from the UK is that the clinical presentation seems to be slightly different.

What new symptoms/clinical presentations have been established?

The UK study has revealed new symptoms that were not in the original coronavirus but there is still no strong evidence that is specific to Kenya. They (UK) have a database where they gather all the symptoms of the people who have Covid-19. What has been established now is that the majority of the people who seem to be having the delta variant is not presenting with fever but have flu like symptoms: sore throat, running nose and headache. This, however, has not been confirmed. The more data we get, the stronger evidence we will have.

Is there anything different that the Delta variant does to the body compared to the original virus?

No. It is still the same coronavirus, the same family, nothing changes with how it affects the body. There is nothing that it does to the body that is different from the other variants or the original coronavirus.

Can vaccines help reduce its impact?

The vaccines have proven to work against these variants, albeit in preliminary studies. There is just a slight reduction in the number of people who are responding to the vaccine. That is why the world is concerned with the people who are not vaccinated. It seems to be causing a problem to people who have not been vaccinated compared to those that have received the jab. Concern, therefore, arises in countries that do not have enough vaccines for their citizens.

Is it responsible for the surge in parts of the country where it was first reported?

We could say that, but we need evidence. While we suspect that it could be the reason, we do not have scientific backing for that. Unlike in the UK where there is evidence since most people have already been vaccinated, our country is yet to meet that threshold and no research has been done yet. For us to be able to say that, then we will have to sequence every case of a positive Covid-19 result which is quite expensive for our country. We are only selecting a few cases for genome sequencing since it is quite an expensive affair.

Supposing there was evidence that the Delta variant is responsible for the surge in cases, what should the people living in the hotspot areas do?

Everyone should know that there is no different preventive measure for the original mutant and those that have changed and are of concern. The measures that we have been saying about preventing of Covid-19 will still work. If only people obeyed and followed the guidelines for the prevention of Covid-19, the cases would be very few.

Does the Delta variant have an age bias?

This is also suspected but there is no evidence. For example, in the UK, it is across all the age groups. The thing is, if the outbreak comes to a young population like Africa, and many Africans get affected by the new variant, then it will be because the population of Africa is young. So, there is no evidence that it particularly affects younger or the older people.

It is early to say this, but we will discover this in the fullness of time. It is only the British variant that was found to affect teenagers more but the Delta variant has not had any study done based on age yet.

What next?

Kenyans need to know that coronavirus has not gone away, and it may be coming back hard, and fast. There are measures that have been put in place by the Ministry of Health that you can do as a person and save your life like wearing of masks, practising social distancing and sanitising all the time.