Coronavirus risk may depend on throat bacteria, according to inBiome group study

AMSTERDAM - May 4, 2020 - PRLog -- Dutch researchers today revealed findings from a collaborative study showing a potential link between the bacteria in a person's throat, known as the throat microbiome, and infection by coronavirus.

• Throat bacteria could be key to defence against coronavirus

The findings are part of a study by a number of doctors from leading Dutch medical organisations, including Dr Andries Budding (inBiome, Amsterdam), Dr. Elske Sieswerda (Amsterdam University Medical Center), Dr Bas Wintermans (ADRZ hospital and Microvida, Goes/Breda), and Dr. Martine Bos (inBiome). As emphasised by the researchers, wider validation of the results is certainly needed, but these findings do introduce the interesting idea of what role bacteria plays in a person's immune response to the virus, whether this might provide an indicator to predict a person's risk of catching the virus, or if bacteria could be utilised to confer some additional level of protection. The paper is currently not yet peer reviewed, but is available in pre-print.

Research
One of the most noticeable characteristics of COVID-19 is the high variability in how it affects people, with the risk for severe illness increasing with age.

Indeed, it is well known that the human microbiome is linked to the immune system and there is already evidence that an individual's throat microbiome plays a role in susceptibility to viral diseases. Now, these researchers have shown that there is also a potential role of the throat microbiome in COVID-19.

Samples were collected from 135 patients using throat swabs; the same as used for coronavirus tests. The team then used inBiome's microbiota analysis platform to profile the microbiomes of both the COVID-19 positive and negative patients.

Remarkably, the platform found that there were significantly lower levels of COVID-19 infection among patients with a specific microbiota profile that contained a key cluster of bacteria, while those without this bacterial cluster were twice as likely to test positive for COVID-19. Strikingly, this bacterial cluster is common in the young but rare in older patients. This may help explain the enhanced susceptibility of the elderly to COVID-19.

This research is important as it may well enable scientists to identify the role bacteria play in the immune defence against the virus. Practically, it may result in a tool to identify who has a high risk of contracting the virus or will develop severe symptoms, or whether throat microbiota modification might reduce risk of infection.

"This is the first indication of why there is a link between age and severity of COVID-19," says Dr Dries Budding. "More research is needed but this could provide a critical tool to understand people's risk of catching coronavirus, and maybe even a tool to prevent catching it at all."

Full pre-print scientific paper

inBiome