LONDON — Antoinette Simmons has lived in the United States for the last 10 years, after having lived in England for a decade. Guess which country’s health care system she prefers?

In the U.K., the National Health Service diagnosed and treated her husband’s cancer free of charge. After moving to Atlanta in 2009, Simmons says she was hit with an unexpected bill of $28,000 after having surgery and misreading the fine print in her insurance policy.

"It was a very dark time," she said, "because I just felt that the walls were closing in."

Simmons, 57, a public defender who was born in Jamaica, has a warning for those who are using the future of the NHS — specifically its ability to negotiate drug prices after Brexit — as a campaign issue in the national elections on Dec. 12.

"People should run screaming away from anything that involves the pharmaceutical vampires in the United States getting anywhere near the NHS," she said.

Antoinette Simmons.

Built out of the chaos of World War II, the NHS is now the world's fifth-largest employer, and because of it, no U.K. citizen need face bankruptcy because of medical care, or have to choose between seeing a doctor and keeping the lights on.

But this year, the opposition Labour Party is raising concerns that another Conservative government could "sell off" the NHS to the United States.

"After Brexit, if we have a Conservative government they will be very desperate to have a trade deal with the U.S.," said Sonia Adesara, a doctor who is campaigning on behalf of the Labour Party. "And I think it's very clear the U.S. wants access to our NHS."

"Access," in this sense, refers to the administration’s desire for American pharmaceutical companies to be allowed to fully participate in the U.K. health care market, according to trade objectives published in February.

The NHS budget was $170 billion this year, much of it used to help negotiate low drug prices, scoring bargains Americans can only dream of.

So potentially there is a lot of money to be made in any trade deal between London and Washington after the U.K. leaves the European Union.

The Manchester University NHS Foundation Trust building at Trafford General Hospital in Manchester, previously known as Park Hospital, where the NHS was launched by the then health secretary Aneurin Bevan. Peter Byrne / PA Images via Getty Images file

Labour, which founded the NHS in 1948, frames the choice facing voters this way: Will the U.K. preserve the service as a pillar of postwar society, providing free health care in a system that's rated as the best in the developed world?

Or will the U.K. allow increased influence from the United States, whose far more expensive free-market-oriented model is ranked worst in the world, according to the Commonwealth Fund, a nonpartisan research organization.

Last week, Labour released a trove of government documents covering talks between the U.S. and the U.K. that it says are "proof" the NHS would be on the block if the ruling Conservative Party wins the election and negotiates a post-Brexit trade agreement with the U.S.

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Despite the documents, the Conservatives still repeatedly insist that the NHS would not be part of any post-Brexit trade deal with Washington.

"There are no circumstances in which this government or any Conservative government will put the NHS on the table in any trade negotiation," Prime Minister Boris Johnson said during a televised debate with Labour leader Jeremy Corbyn. "Our NHS will never be for sale."

Opponents point to the prime minister's career and private life, which have been riddled with allegations of lying, as reasons to be skeptical. Most recently the U.K.’s Supreme Court ruled he misled Queen Elizabeth II before suspending Parliament so it could not scrutinize his Brexit plans.

As many as 45 percent of respondents in a poll by Survation in November said they do not trust the prime minister with the NHS.

It's not just Labour and other opposition parties who warn of Johnson’s untrustworthiness.

Nick Boles, a former Conservative lawmaker and chief of staff when Johnson was mayor of London, wrote in The London Evening Standard that the prime minister "will betray the NHS in a heartbeat if that is what it takes to get a trade deal out of his role model — Donald Trump."

'Question of Power'

The sheer unpopularity of Trump in the U.K. has made the specter of NHS interference a potent attack line for Labour, which has been languishing in the polls under the weight of a vicious dispute over allegations of anti-Semitism in the party and its divisive stance on Brexit.

On Sunday, Corbyn leaned into this unpopularity by calling Johnson the "world's leading sycophant" with regard to Trump.

The president and his ambassador in London, Woody Johnson, said this summer that the NHS would be "on the table" in any post-Brexit trade deal, although both later backtracked.

Trump has also vowed to go after what he calls "freeloading" countries — or those that don’t pay the full share of medical research and development. It aligns with what the powerful pharmaceutical lobby has advocated for years.

To our friends in the UK: please cherish, protect, & continue investing in your healthcare system!



Once Big Pharma & special interests get their hands on it, it could take generations to regain.



Millions of people in the US are fighting to have a system half as good as the NHS. https://t.co/gPR2oq7ZSw — Alexandria Ocasio-Cortez (@AOC) December 3, 2019

If the Conservatives win a majority this month, as polls suggest they might, the U.S. could be in a position to strong-arm the British government over the NHS.

Robert Lawrence, a trade expert who served on President Bill Clinton's Council of Economic Advisers, suggested that the U.K. could try to set firm ground rules with the Americans during trade talks, which can't start officially until after Brexit, now slated for Jan. 31.

"It could be made clear to the United States that the NHS is just a nonstarter," he said. "Then it comes back to a question of power: Do you have sufficient leverage to swallow that hot potato? It just it depends on what else you’re prepared to give up."

Giving way on drug prices could put a huge strain on Britain.

Paying the free-market U.S. price would increase the NHS pharmaceutical budget to $58 billion from $23 billion per year, according to University of Liverpool research conducted for U.K. broadcaster Channel 4.

The NHS is the world's fifth largest employer, behind the Department of Defense, the Chinese army, Walmart and McDonald's. Peter Dazeley / Getty Images file

That would put a colossal strain on the NHS's already overburdened finances after a decade of austerity. However, few are suggesting that the NHS would stop being free at the point of access.

Supporters point out that, for all of its faults, the NHS still outshines the U.S. medical system by most measures. That's despite the U.S. spending more on health care, publicly and privately, than any other country.

"The NHS provides world-class treatment as soon as you walk through that door," Adesara, the doctor and Labour activist, said. “I think that's a pretty amazing thing — that everyone gets this amazing care no matter who you are and how much money you have."