Availability of Rapid Antigen Test (RAT) kits for home use has made it possible for citizens to detect Covid and go for early treatment. On the flip side, due to its lower sensitivity, it often gives false negative results. It means a person whose test is negative becomes assured that he or she does not have Covid, which can prove fatal in certain cases and spread it further among family and friends.
Doctors opine that if the RAT test comes negative but Covid symptoms like fever, sore throat persist then itâ€™s better to consult your physician.
According to medical experts and pulmonologists, the sensitivity (accuracy) of RAT kits, available over the counters at medical stores, is 60 per cent while specificity is 100 per cent. A 100 per cent sensitivity means that if the test comes positive then thereâ€™s no need to go for further confirmatory tests like RT-PCR.
Dr Amit Patel, a consulting pulmonologist at CIMS Hospital, said, â€œThe sensitivity of the RAT kit is 60 percent which means greater chances of missing the diagnosis. If the RAT kit gives a positive result, then it must be considered positive. In that case one must immediately start Covid treatment under a doctorâ€™s supervision.â€
Dr Patel opined that RAT kits can be used for screening at home (primary investigation) as most of his patients, who used it, were positive. The RT-PCR tests have better sensitivity or accuracy.
Dr Saurabh Vanzara, a consultant pulmonologist at Krishna Shalby Hospital said, â€œOf the 10 Covid patients I attended in the last three weeks, five had conducted RAT at home. If RAT is positive then one must not waste money for retesting. Itâ€™s better to get isolated and start treatment by consulting a doctor.â€
The kits are mostly used by youngsters, say chemists in the city. People stock it for their maids/house helps and family members for immediate testing, if they show tell-tale Covid symptoms.
Shailja Kushwah, an IT consultant, recently suffered from a sore throat and fever. Realising the danger, she bought a RAT kit and it gave a positive result.
â€œI did not want to take the chance of spreading the infection to my parents and siblings. So, I took the RAT and immediately started treatment. The kit helped me assess the situation in time so that I could isolate myself, break the chain and safeguard my family from the infection.â€
In the last three weeks, the sale of self-testing RAT kits has gone up 2,000 per cent. Federation of Gujarat State Chemist and Druggist Association (FGCDA) data says Ahmedabad accounts for 50% of RAT kitsâ€™ sales in Gujarat.
President of FGCDA Alpesh Patel said, â€œTill first week of January hardly 5,000 RAT kits were sold per day in Gujarat. The figure went up to 1 lakh kits per day in the last three weeks.â€
Giving reasons for highest sales in Ahmedabad, Patel said, â€œThe awareness about RAT kits is high here compared to other places.â€
Ankit Shah of Shree Gajanand Medical Store in Jivraj Park said, â€œI sell 10 to 15 kits per day at present. People have become aware and itâ€™s convenient to use. Depending upon the brand, it costs between Rs 250 to Rs 350.â€