'I ate a slice of lemon and it did nothing'
says one Coronavirus sufferer as he tells of loss of smell/taste he experienced.
In May 2020, Anosmia (loss of smell/taste) was officially added to the symptoms of Covid-19! The link remained a mystery - until now!
Scientists discover why COVID-19 causes loss of smell
The symptom is one of the earliest indicators that a person has COVID-19, but the reasons for it have been unclear - until now.
The symptom is one of the earliest and most commonly reported indicators that a person has been infected with COVID-19, but the reasons for it have been unclear - until now.
Experts from Harvard Medical School in the US have identified the cell types used for smelling which are most vulnerable to infection by SARS-CoV-2, the virus that causes COVID-19. They found that sensory neurons that detect and transmit the sense of smell to the brain are not among the vulnerable cell types.
Instead, the team found that coronavirus attacks the cells that provide metabolic and structural support to the sensory neurons, as well as certain stem and blood vessel cells.
The findings suggest that in most cases coronavirus is unlikely to lead to persistent loss of smell - medically known as anosmia - a condition that can be associated with mental health issues including depression and anxiety.
Study author Sandeep Robert Datta, a professor of neurobiology at Harvard Medical School, said: "Our findings indicate that the novel coronavirus changes the sense of smell in patients not by directly infecting neurons but by affecting the function of supporting cells.
"I think it's good news, because once the infection clears, olfactory neurons don't appear to need to be replaced or rebuilt from scratch.
"But we need more data and a better understanding of the underlying mechanisms to confirm this conclusion."
Most COVID-19 patients experience some level of anosmia, which is usually temporary, according to the researchers.
COVID-19 patients are 27 times more likely to have smell loss than those without the disease, but are only around 2.2 to 2.6 times more likely to have fever, cough or respiratory difficulty, the experts said.
Some studies have also suggested that anosmia in COVID-19 differs from when the condition is caused by other viral infections, including other coronaviruses.
For example, COVID-19 patients typically recover their sense of smell over weeks, rather than the months it can take to recover from anosmia caused by other viral infections.
In May 2020, loss of taste and smell added to official list of COVID-19 symptoms.
Also, many viruses cause temporary loss of smell by triggering upper respiratory issues such as a stuffy nose.
However, some COVID-19 patients experience anosmia without any nasal obstruction.
The team behind the study hope their findings help efforts to better understand loss of smell in people with COVID-19, which could lead to treatments for anosmia.
Prof Datta said: "Anosmia seems like a curious phenomenon, but it can be devastating for the small fraction of people in whom it's persistent.
"It can have serious psychological consequences and could be a major public health problem if we have a growing population with permanent loss of smell."
Based on
https://news.sky.com/story/amp/coronavi ... l-12038574
[quote]'I ate a slice of lemon and it did nothing'[/quote] says one Coronavirus sufferer as he tells of loss of smell/taste he experienced.
[attachment=0]covid-19 loss of smell.jpg[/attachment]
In May 2020, Anosmia (loss of smell/taste) was officially added to the symptoms of Covid-19! The link remained a mystery - until now!
[size=150][b]Scientists discover why COVID-19 causes loss of smell[/b][/size]
The symptom is one of the earliest indicators that a person has COVID-19, but the reasons for it have been unclear - until now.
The symptom is one of the earliest and most commonly reported indicators that a person has been infected with COVID-19, but the reasons for it have been unclear - until now.
Experts from Harvard Medical School in the US have identified the cell types used for smelling which are most vulnerable to infection by SARS-CoV-2, the virus that causes COVID-19. They found that sensory neurons that detect and transmit the sense of smell to the brain are not among the vulnerable cell types.
Instead, the team found that coronavirus attacks the cells that provide metabolic and structural support to the sensory neurons, as well as certain stem and blood vessel cells.
The findings suggest that in most cases coronavirus is unlikely to lead to persistent loss of smell - medically known as anosmia - a condition that can be associated with mental health issues including depression and anxiety.
Study author Sandeep Robert Datta, a professor of neurobiology at Harvard Medical School, said: "Our findings indicate that the novel coronavirus changes the sense of smell in patients not by directly infecting neurons but by affecting the function of supporting cells.
"I think it's good news, because once the infection clears, olfactory neurons don't appear to need to be replaced or rebuilt from scratch.
"But we need more data and a better understanding of the underlying mechanisms to confirm this conclusion."
Most COVID-19 patients experience some level of anosmia, which is usually temporary, according to the researchers.
COVID-19 patients are 27 times more likely to have smell loss than those without the disease, but are only around 2.2 to 2.6 times more likely to have fever, cough or respiratory difficulty, the experts said.
Some studies have also suggested that anosmia in COVID-19 differs from when the condition is caused by other viral infections, including other coronaviruses.
For example, COVID-19 patients typically recover their sense of smell over weeks, rather than the months it can take to recover from anosmia caused by other viral infections.
In May 2020, loss of taste and smell added to official list of COVID-19 symptoms.
Also, many viruses cause temporary loss of smell by triggering upper respiratory issues such as a stuffy nose.
However, some COVID-19 patients experience anosmia without any nasal obstruction.
The team behind the study hope their findings help efforts to better understand loss of smell in people with COVID-19, which could lead to treatments for anosmia.
Prof Datta said: "Anosmia seems like a curious phenomenon, but it can be devastating for the small fraction of people in whom it's persistent.
"It can have serious psychological consequences and could be a major public health problem if we have a growing population with permanent loss of smell."
Based on https://news.sky.com/story/amp/coronavirus-scientists-discover-why-covid-19-causes-loss-of-smell-12038574