A man in the United States (US) tested positive for Covid-19 for the second time and reported that the second infection was more dangerous than the first.
According to the BBC, the 25-year-old needed hospital treatment after his lungs did not get enough oxygen into his body.
The man involved did not have health or immunity problems that could make him vulnerable to Covid-19.
The Nevada man was confirmed positive for the first time on April 18. However, on May 9 and 26, he was confirmed negative.
However, on May 28, he experienced all the symptoms such as fever, dizziness, cough, vomiting and diarrhea. On June 5, the man was confirmed positive for the second time.
But a study in the journal Lancet Infectious Disease raises the question of how much immunity can fight the virus.
A group of scientists informed the man had two different Covid-19 viruses based on the genetic code of the virus being tested.
"Our findings show that previous infections do not necessarily protect the body from subsequent infections.
"The possibility of re-infection can have significant implications for our understanding of Covid-19 immunity," said Dr. Mark Pandori from the University of Nevada.
Pandori added that although Covid-19 patients have recovered, they need to continue to follow established health guidelines such as social incarceration, wearing face masks and frequent hand washing.
