Mystery surrounds the mailout of a controversial letter penned by two federal MPs criticising Queensland health officials over a disproven COVID treatment, with the Coalition politicians claiming the mastermind of the junk mail campaign is not them.

Craig Kelly and George Christensen wrote a letter to QLD chief health officer Jeanette Young several weeks ago, but both claim to know nothing about its distribution to countless letterboxes across the state.

Mr Kelly, Liberal MP for Hughes in NSW, and Mr Christensen, Nationals MP for Dawson in QLD, co-wrote a letter to Dr Young in September.

The subject was hydroxychloroquine, a drug touted as a COVID treatment which has been debunked in multiple studies.

Labor’s shadow health minister Chris Bowen has also weighed in, calling for the Prime Minister to rein in “misinformation” spread by the maverick MPs. He further warned the mystery over the letter distribution posed “risks to our democratic processes”.

In the letter, the pair criticised the CHO for not making the drug widely available in Queensland.

Mr Kelly and Mr Christensen claim in the letter that extending a ban on hydroxychloroquine treatment for COVID “could be both a breach of Human Rights and potentially constitute ‘Crimes Against Humanity’.”

“We trust you will do the right thing by all Queenslanders and in fact all Australians and not extend this order,” they wrote.

The Therapeutic Goods Administration said it “strongly discourages” using the drug against coronavirus, outlining “limited evidence for effect”, and ” risk of significant adverse effects” like heart, eye and blood sugar issues.

“In terms of its use for this particular disease [COVID], the jury’s pretty much out. It doesn’t work,” chief medical officer Paul Kelly said in August.

Liberal MP Craig Kelly says he didn’t distribute the letter in QLD. Photo: AAP

The letter was shared on the MPs’ social media pages. However, in recent days, many Queenslanders reported receiving copies of the letter in their mailboxes, just weeks from the state election.

Mr Kelly said while he and Mr Christensen had written the letter, they were not behind its mailout.

“Neither George nor myself have had printed or distributed any copies to anyone,” Mr Kelly told The New Daily.

Mr Christensen claimed to the Courier-Mail newspaper “it has been letterboxed to households by a third party”.

Mr Kelly said he stands “100%” by the contents of the letter, alleging studies showing hydroxychloroquine was ineffective were “medical negligence of the highest order”.

The letter, appearing under a letterhead with the Commonwealth coat of arms, also arrived in some mailboxes in unaddressed envelopes bearing the same coat of arms.

This is how it appears in the letter box. pic.twitter.com/9fZ8yWQfjw

— ✌Liz Franklin. (@Mcali4) October 13, 2020

The letter does not carry a standard electoral authorisation message, as required for political mailouts and posters.

It is unclear how the letter is being distributed, or by whom.

Mr Kelly has come under fire from health professionals and opposition MPs over his continual spruiking of hydroxychloroquine, an anti-malaria drug which came to prominence when mentioned by US President Donald Trump as a possible COVID treatment in the early days of the pandemic.

The Hughes MP stoked outrage when he claimed on Facebook in August there was “a special place in hell” for those opposing the drug, who had “the blood of tens of thousands on their hands.”

The same month, he mused whether politicians – specifically, Victorian Premier Daniel Andrews – could be liable for ‘workplace manslaughter’ for not making the drug more available.

Scott Morrison has previously shrugged off questions about Mr Kelly’s relentless Facebook posts about the drug, but Mr Bowen has called on the PM to take action over the letter to Dr Young.

Despite mystery swirling over how printed copies made their way into QLD mailboxes, Mr Bowen claimed the letter was cause for concern.

Chris Bowen has written to the PM calling out the letters’ “misinformation”. Photo: AAP

“I write to urge you to act on the latest effort by your colleagues Craig Kelly and George Christensen to spread misinformation on the drug hydroxychloroquine,” Mr Bowen wrote in an “urgent” letter to Mr Morrison.

In the correspondence, obtained by The New Daily, the Labor MP claims the Coalition pair were sharing “discredited and dangerous claims” about the drug and COVID.

“I note claims by Mr Kelly and Mr Christensen that, while they authorised the letter, they do not know who is mailing out to Queenslanders,” Mr Bowen wrote.

If true, this is an even more alarming development, with anonymous third parties now amplifying misinformation from Government MPs during the Queensland state election.

“This poses obvious risks to our democratic processes, as well as the health of all Australians.”

“I urge you to now condemn Mr Kelly and Mr Christensen, defend your own independent medical experts, and ensure all Australians receive evidence-based information on COVID-19.”

Health Minister Greg Hunt resisted condemning his colleagues on Wednesday, but said federal health officials did not support the drug’s use at this stage.

“There are others who are entitled to put their views. It’s not something we have adopted, we will follow the medical advice,” Mr Hunt said in response to TND’s question.

He added that the federal government was supporting a trial of the drug, conducted by the Walter and Eliza Hall Institute in Melbourne.

“We set out the medical policy based on the medical advice. Others will set out their views, and I will leave it to them, on their views,” Mr Hunt said.

“But I’m very clear, our policies are determined on the basis of medical evidence and medical advice.”