Home / Science / Omicron symptoms but didn't test Covid positive? Doctor explains reasons

Have symptoms of Covid-19? Did you get yourself tested? Was the report negative despite the symptoms? Doctors have been observing rising cases of negative RT-PCR tests and patients complaining of symptoms. According to them, there are a multitude of reasons why tests are turning back negative

Dr. Bharesh Dedhia, Chief Consultant, Critical Care at P. D. Hinduja Hospital & Medical Research Centre, Khar Unit says this might be due to the fact that certain testing methodologies are improper, swabs are not collected properly, and sample storage during the transportation is not done appropriately.

“Some Omicron variants may test negative on RT PCR, particularly the RAT, as we know that the RAT's sensitivity is approximately 50%," says Dr Bharesh Dedhia.

One of the most important factors, in my opinion, is that the viral load is quite low. So we have what is called a CT value, also known as a cyclic threshold value. And, according to ICMR guidelines, if the CT value is greater than 35, the test is considered negative. So, if a person's viral load is very low, his or her cyclic threshold will be greater than 35, and the test will be reported as negative. Lastly, in RT-PCR, some Omicron variants could test negative, he adds.

The new variant is detected by the majority of RT-PCR tests. “If the S gene drop is seen in the RT PCR test, it is most probably Omicron, and if the S gene is present, it is most likely a Delta variant. This is how the RT-PCR detects the new variant. However, confirmation has to be done via Gene Sequencing," he explains.

Genome sequencing helps in understanding the difference between two variants of the same virus and makes treatment more effective.

If an individual has typical Covid symptoms and the RT PCR is negative, he or she should isolate for at least seven days. The individual can also repeat the home test and the RT PCR at the end of the fifth or sixth day to check if it is now turning positive or if it is still showing negative.

Symptoms of Omicron

According to US CDC analysis, the five most common symptoms of the Omicron variant are cough, fatigue, congestion, runny nose and generalised body ache. 

Dr Harish Chafle, Senior Consultant - Pulmonology and Critical Care at Global Hospital, Parel, Mumbai says symptoms are classified into most common symptoms, less common symptoms and serious symptoms.

Most common symptoms of Omicron

Fever, cough, tiredness, loss of taste or smell.

Less common symptoms of Omicron

Sore throat, headache, aches, pains, diarrhoea, a rash on the skin, discolouration of fingers or toes red or irritated eyes.

Serious symptoms of Omicron

Difficulty breathing or shortness of breath, loss of speech or mobility, or confusion or chest pain.

Meanwhile, India reported a down surge in coronavirus infections as the country recorded 255,874 new Covid cases today.





Sangeeta Ojha

Sangeeta is a Chief Content Producer at Livemint. Writes on personal finance, banking and real estate. She has over 12 years of experience as a journalist with television and digital media
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