With the highly transmissible omicron variant of the coronavirus driving a surge in COVID-19 cases worldwide, experts have noted that the new strain is in some respects different from the older variant, Delta.

For starters, while extant two-dose COVID-19 vaccine regimens were effective against Delta, an increasing body of scientific evidence suggests that omicron bypasses the immunity offered by extant COVID-19 vaccines, which makes the strain particularly transmissible.

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In terms of symptoms, there also exist differences between the two variants, despite them sharing certain similarities.

Cough, cold, and fever are symptoms that are common to both omicron and Delta. A sore throat is also a common symptom of omicron, although it might also arise in case of a Delta infection. Similarly, headaches, fatigue, and body aches are primarily symptoms of omicron, although such symptoms may exhibit themselves in rare cases of Delta infections.

The biggest difference in terms of symptoms between omicron and Delta, however, is the existence or absence of severe breathing difficulties. While Delta infections often resulted in breathing difficulties among patients, extant scientific evidence suggests that breathing difficulties are an extremely rare symptom of omicron.

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Experts say that an indication of an omicron infection can be deduced from symptoms, with the most common symptoms of an omicron infection being upper respiratory system symptoms, such as cold, cough, and a sore throat, and gastrointestinal (GI) symptoms, such as nausea, vomiting, and diarrhoea. Fever coupled with body aches, especially in the lower back region and upper limbs, are also quite common for omicron infections.

However, while the aforementioned information is a general indication of the type of infection, it should not be seen as an absolute indicator. Experts have said time and again that symptoms vary from person to person, and the extent and severity of symptoms is dependent on various individual factors such as immunity, the existence or absence of underlying health conditions, and vaccination status.