Children’s noses can fight COVID-19 better than adults’ noses.
Dr Kirsty Short from the University of Queensland’s School of Chemistry and Molecular Biosciences says this may be one reason why immune responses in children have been shown to be more effective against the virus.
“Children have a lower COVID-19 infection rate and milder symptoms than adults, but the reasons for this are unknown,” she says.
“We showed that the nasal mucosa of children has a more pro-inflammatory response to ancestral SARS-CoV-2 than the nose of adults.”
Get Crikey FREE in your inbox every weekday morning with the worm crikey.
Dr. Short and his colleagues exposed cell samples from the nasal mucosa of 23 healthy children and 15 healthy adults to the virus.
The results showed that it replicated less efficiently in children’s nasal cells and there was an increased antiviral response.
“It could be an adaptation to increased threats from ‘foreign invaders’ such as viruses or bacteria seen in childhood,” she said.
“It’s also possible that increased exposure to these threats in childhood ‘triggers’ the nasal mucosa in children to mount a stronger pro-inflammatory response.
“Or alternatively, metabolic differences between children and adults could alter how genes that fight the virus are expressed.”
The researchers found that the Delta COVID-19 variant was significantly less likely to replicate in children’s nasal cells, but the trend was significantly less pronounced in the case of Omicron.
Meanwhile, state and federal authorities fear the number of Australians receiving their third dose of the COVID-19 vaccine is lagging.
Some 71.4% of eligible people, or just over 14.1 million people, have so far received a third dose.
But there are more than 5.6 million who have not yet received their reminder.
Queensland is the worst performing state, with 64.5% of eligible residents receiving a third shot, while the ACT has the best coverage (79.9%).
The recall rate is 55% for Indigenous Australians nationwide.
The concern comes amid nearly 29,000 new cases of the virus recorded across the country on Saturday with 89 deaths.
Although it has been declining daily over the past week, the number of hospitalized virus patients also remains slightly below 4,500, or nearly one in every 12 hospital beds.