Virus World

The symptoms suggest SARS-CoV-2 might infect neurons, raising questions about whether there could be effects on the brain that play a role in patients’ deaths, but the data are preliminary. Nearly two weeks ago, Alessandro Laurenzi, a biologist working as a consultant in Bologna, Italy, was mowing the grass in his garden when a friend stopped him and said the mower reeked of fuel. “I couldn’t smell anything at all,” he tells The Scientist. That was in the morning. A few hours later, he went to have lunch and realized he couldn’t smell the food he was about to eat and when he took a bite, he couldn’t taste it either. Within a few days, he developed symptoms of COVID-19 and called his doctor to ask if he could get tested. Because his symptoms were mild, Laurenzi says, his doctor said no. Laurenzi had heard anecdotally that many COVID-19 patients in Italy suffered from a loss of smell, so he started reading all the scientific papers he could find to see if his anosmia and ageusia would ever abate. One of the papers, a review published March 13, mentioned that SARS-CoV-2, like other coronaviruses such as SARS-CoV and MERS-CoV, could target the central nervous system, possibly infecting neurons in the nasal passage and disrupting the senses of smell and taste. 

 

Reading this, Laurenzi immediately reached out to the corresponding author, Abdul Mannan Baig, a researcher at Aga Khan University in Pakistan, and asked if his symptoms were reversible. The evidence, Mannan told Laurenzi and reiterated to The Scientist, indicates they will abate, possibly because the loss of sense is caused by inflammation in the area as the body fights the virus, so those symptoms could disappear in seven to 14 days. “Let’s hope so,” Laurenzi tells The Scientist. Documenting such peculiar symptoms is important, Mannan tells The Scientist, because the loss of smell and taste could be an early warning sign of SARS-CoV-2 infection. Based on the literature, British ear, nose, and throat doctors have now called for adults who lost those senses to quarantine themselves in an attempt to tamp down the spread of the disease, The New York Times reports. The symptoms, Mannan adds, also suggest that the virus has the ability to invade the central nervous system, which could cause neurological damage and possibly play a role in patients dying from COVID-19.