So far 3,245 people have tested positive for brucellosis, while a further 1,401 people are suspected to have the disease. Symptoms of the disease, also known as Malta fever or Mediterranean fever, include fever, headaches, muscle pain, and fatigue.
The outbreak comes after a leak at the Zhongmu Lanzhou biological pharmaceutical factory, thought to have taken place between late July to August last year.
The factory used expired disinfectants and sanitisers while producing Brucella vaccines for animals.
The contaminated waste gas then formed aerosols, which contained bacteria and leaked into the air.
The possibility of human-to-human transmission is said to be extremely rare.
Most people are thought to be infected by eating contaminated food or breathing in the bacteria.
Brucellosis is an infectious bacterial disease that spreads from animals to people.
It commonly occurs among dogs, sheep, cattle, goats and pigs.
The news comes as China remains gripped in the middle of the COVID-19 pandemic as the invisible killer disease continues to spread in the country it originated in in December last year.
More to follow…