The Delta variant of the coronavirus is becoming more prominent in many countries - including Belgium - and according to new research, the symptoms are slightly different from previous strains of the virus.
Several virologists, both internationally and in Belgium, have said this will be a mutation to watch. Here's what you need to know about the Delta variant.
What are the symptoms and how do they differ from the traditional ones?
Based on data from the ZOE Covid symptom study, an app-based research in the United Kingdom, where the Delta variant accounts for 90% of the cases, people testing positive with this particular strain are reporting new symptoms.
According to the World Health Organisation (WHO), the most common symptoms for the original strain are:
- A fever,
- A dry cough,
- Fatigue,
- A loss of taste and smell.
With the Delta variant, however, fever and cough are less common symptoms, whilst loss of smell doesn't appear in the top 10 of the most common symptoms list.
As such, the most common symptoms of the Delta strain are:
- A headache,
- A sore throat,
- A runny nose.
This similarity in symptoms with the common cold is the reason this particular variant is being flagged as one to watch.
"Covid is acting differently now. Young people might think they just have a seasonal cold and can still go to parties. We think that's a major cause of the spread of the variant," genetic epidemiology professor Tim Spector, who studied the spread of the variant in the United Kingdom, said in a video last week.
The symptoms linked to the Delta strain are also very similar to those connected to hay fever, which typically causes a runny nose, cough, shortness of breath (in case of asthma), and at times a sore throat if pollen levels are high enough (which they currently are in Belgium).
If you are unsure about whether you have Covid, it is best to get tested just in case.
Is the Delta strain more contagious or deadly?
The Delta variant is 60% more contagious than the Alpha variant, and it is more likely to lead to hospitalisation, according to a study by the British health authorities, Public Health England (PHE), published last Friday.
The PHE highlighted that it was "encouraging" that this increase is not accompanied by an increase in hospitalisations in the same proportions as seen in the UK.
However, according to doctors in China, people infected with this variant are becoming sicker and their conditions are worsening much more quickly than people who have been infected with the initial strain of the virus first detected in Wuhan.
So far, no research has been published on whether the mutation is more deadly.
How prominent is the variant in Belgium?
In Belgium, the Delta variant still accounts for just 3.9% of all infections, according to the most recent update from health institute Sciensano, however, it noted the prevalence of this strain is increasing.
The spread of the variant in Belgium could go two ways, according to Piet Maes, a virologist at KU Leuven's Rega Institute.
"In Belgium, the overall infections are decreasing steadily, the vaccination rate is very high, which are positive signs at the moment. However, it is not abnormal that this variant would take the upper hand, it is difficult to estimate. So it is important to keep the number of infections as low as possible," he told Radio 1 on Tuesday.
Virologist Steven Van Gucht agrees that an increase in the spread of the strain is not inconceivable, but he told VRT News that he doesn't "expect a big impact on hospitals."
"It will become more important in the infections in the coming weeks. But it remains a very low number," he said.
Are the current vaccines effective against the Delta variant?
According to another study carried out by PHE, both the Pfizer and AstraZeneca coronavirus vaccines are effective against the Delta variant, but only after both doses have been administered.
- The Pfizer-BioNTech vaccine is 96% effective against hospitalisation after 2 doses
- The Oxford-AstraZeneca vaccine is 92% effective against hospitalisation after 2 doses
Whilst one dose of both vaccines reduced the risk of developing Covid symptoms by about 51% in the case of the Alpha variant, the protection after just one dose was lower (34%) against the Indian variant, according to Van Gucht.
Last Tuesday, Belgium’s Vaccination Taskforce stressed the importance of getting both vaccination doses in time, mainly as a result of the increasing circulation of the Delta coronavirus variant.
The UK's vaccination strategy focused on giving as many people as possible the first dose first, which could have played a part in this particular variant spreading more quickly.
Additionally, Belgium's task force has also argued for the threshold for herd immunity should be raised due to the Delta variant.
"Higher than the 70% that was assumed at the start of the vaccination campaign [will be needed]. Only in this way can we sustainably return to normal life," said the task force's spokesperson Gudrun Briat.
