Then vs. Now: How COVID-19 symptoms have changed over time

COVID-19 in early 2020 vs. now surely looks different, not just in terms of how the virus itself has evolved, but also in the way people have started to approach it in recent times.

The Delta wave or the second coronavirus wave in India was extremely devastating and something none of us had ever witnessed. But with the Omicron variant, illnesses have taken a milder turn. Why? It's still impossible to give a specific reason. However, scientists believe both natural immunity and immunity acquired from the vaccines could have a role to play.

In addition, it is interesting to see how, with milder infections becoming more dominant, the COVID symptoms have changed over time...

Also read: Has India attained herd immunity against COVID? Experts answer

As the SARs-CoV-2 virus continues to mutate, the symptoms reported by COVID-infected patients are changing as well.

Earlier this year, a survey of 17,500 patients in the United Kingdom found that the loss of taste and smell were no longer predominant symptoms of COVID. Furthermore, fewer people reported high fever, shortness of breath, and loss of taste with the Omicron variant compared to the Alpha and Delta variants.

During the early stages of the pandemic, especially the Delta wave, loss of smell was reported by about half of COVID patients.

Also read: COVID, flu, cold: Distinct signs of these infections everyone should know

Sore throat, runny nose, nasal congestion, persistent cough, and headache are currently the reigning COVID symptoms, according to the Zoe Health Study.

The study found that the new list of COVID symptoms differs from the traditional more severe COVID-19 symptoms such as persistent cough, loss of smell, fever, and shortness of breath.

It involved participants, who tested positive between June 1 and November 27, 2021 (when the Delta variant was dominant) and between Dec. 20, 2021 to Jan. 17, 2022 (when the Omicron variant dominated).

Altogether, they collected 62,002 positive tests and analysed the symptoms experienced by each participant.

In addition, the study also revealed that the Omicron is far less likely to impact the lower respiratory tract, which is where the virus seems to cause more damage and give light to severe symptoms.

While scientists are yet to find answers to why there has been a shift in the kind of symptoms experienced by COVID patients, many believe it could be attributed to the mutating variants and how each affects the body differently.

As compared to the Delta variant, which attacks the lower respiratory system, the Omicron variant thrives on the upper respiratory tract.

While the upper respiratory tract consists of the nose, nasal cavity and the pharynx, the lower respiratory tract is associated with the larynx, trachea, bronchi and the lungs. This is why those infected with the Delta had more severe pneumonia-like symptoms, whereas Omicron patients often have symptoms similar to the common cold, says a June article by Infectious Disease Reports.

A recent ZOE Health study conducted by health science company ZOE and researchers from King’s College London, Massachusetts General Hospital, Harvard and Stanford University, found that COVID-19 symptoms may also differ depending on one's vaccination status.

Those who are fully vaccinated are likely to experience sore throat, runny nose, blocked nose, persistent cough, and headache.

People who have had only one COVID vaccine dose may develop headache, runny nose, sore throat, sneezing and persistent cough.

Unvaccinated individuals are likely to report headache, sore throat, runny nose, fever and persistent cough.

According to the study authors, "If you’ve been vaccinated and start sneezing a lot without an explanation, you should get a COVID test, especially if you are living or working around people who are at greater risk from the disease."

COVID-19 may have become milder for some, but it still is very prevalent and poses great risk to people who have pre-existing health conditions, immunocompromised people and older adults.

While previous infections and vaccine-induced immunity may have boosted our immune systems, there is still a great chance of re-infection.

That said, make sure to wear your masks, maintain social distance, maintain proper hand hygiene and stay isolated if you develop COVID-like symptoms.