New Delhi: People across the world are taking a COVID negative test as their ticket to living a normal life and taking part in festivities. But experts say a negative report does not guarantee that the person will not spread COVID-19.
On the contrary, scientists say that it creates false hope. Their advise is that a person who has been exposed to Sars-Cov-2, the virus which causes the coronavirus disease, should still follow the mandated guidelines as a precautionary measure, Hindustan Times (HT) reported.
“You should not rely on test results alone to safely socialise in person. A test can only tell you if you are positive at a given moment in time, and can also fail to detect cases if you are infected but not yet shedding substantial virus,” Dr Angela Rasmussen, a virologist affiliated with Georgetown Center for Global Health Science and Security, was quoted as saying by news agency Reuters.
Incubation period
A person who has been exposed to the virus can take days to actually show symptoms of the viral disease. Experts say a test result could fail to detect the presence of the virus in the body if the exposed person is tested shortly after getting infected. The virus needs to reproduce enough copies of itself for it to be detected in the COVID-19 tests. The incubation period for COVID-19 is up to 14 days. And before that, a person can test negative and have no symptoms at all.
There is also a possibility that a person may contract the virus after getting the test done. Hence it is advisable for the exposed person to stay under quarantine for at least a week after exposure to the virus, the report added.
The various types of tests
Antigen test: This is a rapid test and gives you results within an hour or so. It is performed with nasal swabs and looks for the presence of a specific protein on the surface of the virus. As the person gets results within hours, the test is widely being used to test asymptomatic persons. But there is a high chance of getting a false negative report with this test.
Molecular tests: This is the RT-PCR test that looks for the genetic material of the virus in the body. This test is performed with nasal swabs or throat swabs or both. An RT-PCR test is more credible but it takes longer to give you results.
