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By Cheryl Kahla

Content Strategist


Delta variant symptoms: Here’s what to look out for

The symptom profile for the Delta variant differs from the initial Covid-19 symptoms and may slip under the radar.


Lara Herrero, a researcher at the Griffith University in Australia studying the glycobiology of vector-borne diseases, says people infected with the Delta variant experience symptoms different to those commonly associated with Covid-19.

The most common Covid-19 symptoms include fever and coughing along with a loss of taste and smell, while very few patients present with a headache and sore throat.

Delta variant symptoms

The Delta variant, however, follows a different set of rules. The loss of smell, for example, is not as prevalent with the Delta variant as it was with the variants driving the first two waves.

In addition, a medical specialist at the Western Cape health department, Professor Mary-Anne Davies, said the symptom profile for the Delta variant seemed to be more like the common cold.

That includes a runny nose and sneezing, even if the patient shows no signs of a fever. She said the new data was important “because people may think I just got a normal cold and may not realise that they are a case and they need to isolate”.

The top five symptoms at the time of publishing include:

  • Headache
  • Sore throat
  • Runny nose
  • Fever
  • Persistent cough

Why do the symptoms change?

When a virus is widely circulating in a population – especially when a rise in new infections is recorded – the likelihood of the virus mutating increases the further it spreads as it has more opportunities to replicate.

Herrero explained why symptoms change remained uncertain. However, there were a few possible contributing factors:

  • It could be related to the way in which data received from hospitals are processed. Herrero said, “patients presenting to hospital were likely to be sicker”.
  • Moreover, she says it could “also be because of the evolution of the virus, and the different characteristics (viral factors) of the Delta variant”.

“While we still have more to learn about the Delta variant, this emerging data is important because it shows us that what we might think of as just a mild winter cold – a runny nose and a sore throat – could be a case of Covid-19,” she warned.

ALSO READ: Limpopo residents urged to be careful as Covid-19 cases quadruple

Delta’s impact on Covid-19 vaccines

The Covid-19 vaccines currently in development offer some protection against new strains. This is because vaccines in general “elicit a broad immune response involving a range of antibodies and cells”, the World Health Organization (WHO) explained.

Professor Penny Moore on 2 July said existing laboratory data suggests “vaccines in use in South Africa will work better against the Delta variant than the Beta variant”.

In addition, Professor Glenda Gray said: “All the data we see indicate immediate and sustained immune response against Delta, and we see surprising durability in the immune response for the single-dose J&J [Johnson & Johnson] right up to eight months.”

It has thus far been reported both the Pfizer and AstraZeneca vaccines show greater than 90% protection in patients who required hospital treatment after contracting the Delta variant.

If an infection does occur after vaccination, the viral load will likely be lower, manifesting in milder symptoms.

At the time of publishing, Gauteng accounted for 60% of new cases recorded on Monday.

NOW READ: Vaccines in SA are effective against the now-dominant Delta variant

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