Brucellosis is a condition transmitted by animals or products of animal origin. In general, it is not contagious from person to person. But it can cause fever, joint and headaches.

A total of 3,245 people were tested and positively diagnosed with the bacterium, a figure set as a result of tests conducted after the incident, according to health authorities in Lanzhou, the capital of Gansu province. They stated that no case of Community transmission had been reported.

A public laboratory in the city used an expired disinfectant in July-August 2019 during the production of brucellosis vaccines for animals, authorities said on Tuesday.

Therefore, sterilization was incomplete and the bacterium was always present in the company’s gas emissions – the Lanzhou Biopharmaceutical Plant for Animal Husbandry.

The contaminated gas spread through the air to the nearby Veterinary Research Institute, where it infected nearly 200 people in December.

The Lanzhou Health Bureau said Friday that the bacteria is generally from sheep, cattle or pigs. The laboratory apologized this year and was left without permission to produce brucellosis vaccines. The patients will receive financial compensation starting in October, according to Lanzhou authorities.