Australian garlic variety can limit internal spread of COVID and influenza A, Doherty Institute finds

An Australian variety of garlic could reduce COVID and flu-related infections, according to new medical research.

A study by the Peter Doherty Institute for Infection and Immunity (the Doherty Institute) and farming company Australian Garlic Producers has found that extracts of an as-yet-to-be-named garlic, have the ability to stop the spread of viral cells from SARS-CoV-2 and influenza A in the digestive system.

The potentially flu-busting garlic is from a commercial crop grown in Merbein, near Mildura, in north-western Victoria.

Doctor Julie McAuley from the Doherty Institute, which is a joint venture between the University of Melbourne and the Royal Melbourne Hospital, led the study.

The team tested about 20 varieties of garlic in different forms, but the laboratory trials found only one type of garlic was effective in curbing the infectivity of the viruses.

Dr McAuley said if this variety of garlic was taken as a dietary supplement it would "combine with the [COVID] virus and prevent it from infecting the cells in our digestive tract".

"We know that [COVID] and flu can both infect our digestive tract, and when outbreaks occur we monitor water waste to see where the virus is being excreted from," Dr McAuley said.

"So we know that people actually have it as a part of their stomach and intestines."

She said the garlic supplement could slow down the virus "so our immune system can actually go on and attack the virus where it mainly infects us — in our respiratory tract".

Dr McAuley said the effective variety of garlic was tested from two different sites, one in the Northern Territory and other in Mildura.

"So that kind of eliminates any kind of soil impact, because they're two very different environments and different soils," she said.

"Because this one garlic variety held the same properties [despite being] grown in two different places, it makes us think it's something about the garlic itself rather than how it was grown.

"So if you have COVID or the flu and feel like your gastrointestinal system is feeling really icky, it will help keep the viral load down there.

"But as a preventative, it's an antioxidant that will help with your normal gut flora."

Australian Garlic Producers chief executive Nick Diamantopolous said that as a result of the discovery his company would be developing dietary supplements.

"Garlic is certainly healthy for you, but not all garlic is the same," Mr Diamantopolous said.

"There are some varieties that are good for flavour, but they don't necessarily all have health benefits."

Over the past 18 months, he has been working with the Peter Doherty Institute to test a wide variety of garlic samples.

"We've got about 309 varieties in our collection, and out of the 20-odd garlic varieties that we tested, one in particular actually had 99.9 per cent viricidal properties," he said.

Mr Diamantopolous said the product must be ingested raw.

"You have to have it fresh like in a salad, or uncooked form, the minute you cook it you'll destroy all the health benefits," he said.

Australian Garlic Producers supply more than 90 per cent of Australia's garlic — 3,000 tonnes per year.

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