RT-PCR coronavirus tests and false negatives: Why is that happening?

As Covid-19 case numbers increase rapidly, and people are finding it hard to get RT-PCR tests done, get a sense of what is happening on the ground

Earlier this month, Arjun Sharma (name changed on request) visited three hospitals in Delhi with his father, trying to get an oxygen bed for him. His father had tested negative for Covid-19 on an RT-PCR test, but was showing symptoms of the disease--his oxygen levels had dropped and a CT scan showed infection and pneumonia in his lungs.

"Doctors who we consulted said that my father most likely has Covid-19 and should get admitted to a hospital to get oxygen support. But the test was negative despite his serious symptoms, and maybe this was a false-negative test result," said Sharma, a