Although there could be a chance that the virus was quite low enough to go undetected and appear negative on a test, only to increase and be picked up in the next test, the question arises as to whether the same virus has resurfaced again or is the current infection caused due to another viral event.
Determining reinfection is quite a challenging process. Genetic material gathered from the first and second swabs of the patient must be analyzed and sequenced by using genetic engineering. If there are differences that show up during sequencing, it means that reinfection has occurred. If the sequences match, then it means that there could be a relapse.
As of now, health officials in India are of the opinion that reinfection with COVID-19 is very rare. Observations till date have shown that only mild infections have occurred and therefore this issue is not of serious concern now.
What should be done once you have recovered from Covid-19?
Recovery from COVID-19 does not mean that you are immune to the disease. You should avoid getting complacent and continue maintaining hand hygiene, wearing masks and ensuring social distancing even after recovery.
Since COVID-19 is a relatively new disease, there is not much data available in order to understand the kind of long-term immunity that patients develop after they have recovered from the infection.