Cough first or high fever first? Each variant of the virus appears to have a different sequence of symptoms

This can also have consequences for the speed with which a particular variant spreads.

COVID-19 affects different people in different ways. Symptoms can vary a lot, or be mild at first. The most common symptoms are fever, cough and fatigue. You can also develop severe shortness of breath or shortness of breath. But what symptoms often appear first? Researchers discovered it.

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Earlier, researchers developed a mathematical model that predicts the sequence of COVID-19 symptoms. This model is based on data from the first coronavirus outbreak in China, early 2020. In The new study However, the research team wanted to know if the order of symptoms differed between patients from different geographic regions or with different personality characteristics. To determine this, they studied the symptom order of more than 370,000 US coronavirus patients diagnosed between January and May 2020.

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Researchers have made a surprising discovery. Because the most likely sequence of symptoms turns out to be very different between Chinese and American coronavirus patients. In China, most corona patients often develop a fever at first. Thereafter, a persistent cough was a common complaint, followed by nausea and sometimes vomiting. On the other hand, American corona patients in many cases were the first to deal with an annoying cough. Diarrhea is a third complaint often mentioned.

Geographical area… or not?
However, an intriguing question is whether these differences are actually related to geographic location, or whether they have another cause. The team analyzed additional data from Brazil, Hong Kong and Japan. This leads to an amazing discovery. The different symptom sequences do not appear to be related to geographic region, weather, or personal characteristics, but rather related to different virus variants.

Variant D614G
The so-called D614G variant was prevalent in the United States in early 2020. As mentioned, coughing was the first common phenomenon there. When the D614G variant replaced the original coronavirus in Japan, the order of symptoms changed here as well. The researchers hypothesize that this may be related to the increased prevalence of D614G.

Virus variants
Thus, the results of the study seem to indicate that each type of virus has a different arrangement of symptoms. A very surprising result. Peter Kuhn said in an interview with Scientias. nl. “We haven’t seen or measured this before in other virus outbreaks.”

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According to the researchers, the discovery could have consequences for the speed at which a particular virus type spreads. “For example, if a fever is the first symptom, the patient becomes incapacitated very quickly,” explains Kuhn. “The patient stays at home and cannot pass the virus on to others. However, if coughing, loss of smell or fatigue is the first symptom, it may take longer for the patient to realize they have the virus. Then it also takes longer before they can be tested.” In this way, this virus variant can spread to many people.

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What exactly causes the difference in symptoms for different viral variants? Kun still owes us the answer. “It’s not clear yet,” he says. It may be related to the mutation or change in the spike protein. But the exact mechanism has not yet been clarified.”

Kuhn stresses that it is very important to map the symptom sequence of emerging virus variants. “Our study provides the necessary evidence that the sequence of symptoms is changing and that we can model this accurately,” he says. “The next step is to keep doing that for the new variants.”