All but one of the dead who suffered health issues had yet to undergo a new comprehensive medical screening intended to detect underlying risks, the supreme committee organising the tournament said.
The checks, along with newly launched electronic medical records and mental health supervision for workers, were introduced following criticism by human rights groups of Qatar's past labour practices.
"With each death, regardless of what NGOs may think, we've always taken a lot of attention and concern," the committee's executive director for worker welfare, Mahmoud Qutub, told AFP.
"The comprehensive medical screening, as a preventative measure, has probably been one of the most effective programmes we have launched."
In 2018, by contrast, one worker died as a result of a workplace accident after falling from a height at the Al-Janoub stadium. Ten non-work related deaths were reported in the same period.
Most of Qatar's 2.75 million residents, 90 percent of whom are foreigners, are from poor developing countries working on projects linked to the 2022 World Cup. Of that number only around 26,000 are directly employed on SC projects.
Three workers were killed and 11 injured in a bus crash in November in what was the single deadliest incident in 2019, according to a committee welfare report.
It added a Turkish carpenter died of heart failure in February 2019, a Nepalese 27-year-old died of cardio-respiratory failure in June, while a 20 year-old Nepalese man killed himself in October 2019 -- five days after arriving in Qatar.
In October 2019 an Indian electrician, 54, died of heart failure while the following month a 35-year-old Nepali died of tuberculosis and in December a 21-year-old Indian worker was found dead in his lodgings. An investigation into the cause of his death is ongoing.
"We could sit back and say 'people die -- they didn't die on the site, it's not our responsibility'. But we wanted to be as transparent as possible," Qutub said.
"We have taken a lot of measures to become more preventative."
The committee has also intensified efforts to identify and reimburse workers wrongly charged recruitment fees, Qutub added.
Standout matches today