Antigen tests for screening corona in Lucknow and NCR districts

LUCKNOW: In a bid to ramp up Covid-19 surveillance, Uttar Pradesh is all set to roll out antigen tests for screening at important centres, including NCR districts and the state capital. This pregnancy kit-like device can reveal the presence of coronavirus in about 30 minutes.
Additional chief secretary, health and family welfare, Amit Mohan Prasad, said on Sunday that the tests will begin in a few days.The Indian Council of Medical Research and All India Institute of Medical Sciences approved the Korean antigen test kit on June 15 week.
“The tests will begin from select cities, including NCR districts of Gautam Budh Nagar and Ghaziabad, besides Lucknow, Kanpur, Varanasi, Gorakhpur and Prayagraj,” Prasad said.
While a positive outcome from this antigen test is deemed as a confirmation of the infection, in case of a negative result, the patient’s sample will be sent for the RT-PCR test to confirm or rule out the presence of virus.
As recommended by ICMR, said officials in UP health department, the kit will be used in containment zones to test suspected persons with influenza-like symptoms and asymptomatic direct and high-risk contacts of confirmed cases.
The kit will also be used for healthcare providers, cancer inflicted patients in need of chemotherapy or those suffering from malignant diseases, besides elderly persons.
Health officials told TOI that the kit contains a pregnancy test kit-like Covid antigen test device, viral extraction tube with a solution (viral lysis buffer) to decode the coronavirus cells, and sterile swab for sample collection.
“Unlike antibody tests which require drawing of blood, the antigen test needs a nasal swab. This swab is collected using the customised sample collection swab provided along with the kit. No other swab, throat or bronchoalveolar lavage or sputum, is needed,” explained an additional chief medical officer with the state surveillance team.
“The swab sample is exposed to the solution provided to see the presence of the covid-19 virus. If the virus is present then lines will appear on the kit just the way it appears on the pregnancy test kit,” he added.
Briefing media about the kit last week, ICMR officials said that specificity (or the kit’s accuracy in detecting true negatives) ranges between 99.3% to 100% based on validation done at two sites while its sensitivity (or the rate of detecting infections correctly) ranged from 50.6% to 84%, based on two independent evaluations. The viral load of the patient may also alter specificity and sensitivity.