The Ministry of Health made the announcement on Monday. It issued a circular on September 17 in this regard.

Antigen-based testing has been permitted at all government hospitals, district hospitals, government PCR labs and all health institutes as per the proposal of the Directorate General of Health Services (DGHS) and the interim guideline of the World Health Organization, according to the circular.

On July 5, the DGHS wrote to the Health Ministry to allow antigen-based Covid-19 testing. The National Technical Advisory Committee on Covid-19 also recommended it several times.

According to the DGHS proposal, antigen tests would be carried out on patients with symptoms. If anyone is found positive, the patient would be isolated.

But if anyone is found negative in the antigen tests, they would be tested again by RT-PCR or GeneXpert machine for confirmation.

Antigen-based tests

Rapid antigen tests are commonly used in the diagnosis of respiratory pathogens, including influenza viruses and respiratory syncytial virus, according to US Centres for Disease Control and Prevention (CDC).

Antigen tests are immunoassays that detect the presence of a specific viral antigen, which implies current viral infection. They are relatively inexpensive and can be used at the point-of-care. Devices used in the tests can return results in about 15 minutes.

Antigen tests for SARS-CoV-2 are generally less sensitive than viral tests that detect nucleic acid using reverse transcription polymerase chain reaction (RT-PCR).

Rapid antigen tests perform best when the person is tested in the early stages of infection with SARS-CoV-2 when viral load is generally highest, CDC says.

There are limited data to guide the use of rapid antigen tests as screening tests on asymptomatic persons to detect or exclude Covid-19, or to determine whether a previously confirmed case is still infectious, CDC notes.

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