After COVID-19, now thousands of people in the northwest region of China have tested positive for another bacterial disease as authorities shared on Tuesday that the outbreak was caused by a leak in a biopharmaceutical company's facility last year.

The Health Commission of Gansu province's capital city, Lanzhou shared that they have confirmed that 3,245 individuals had contracted the disease brucellosis, which is caused by having contact with livestock animals that carry the bacteria called brucella.

The city's Health Commission added that additional 1,401 persons have tested as preliminary positive, but they also emphasized that no fatalities are still recorded because of the bacterial disease.

Based on the latest numbers of the medical authorities, they have already tested 21,847 people out of 2.9 million total population of the city, CNN reported.

Also known as the Mediterranean fever or the Malta fever, the said disease can cause symptoms that include headaches, fever, fatigue, and muscle pain. These mentioned symptoms may subside but other symptoms such as arthritis and swelling in specific organs can become chronic based on the information given out by the Centers for Disease Control and Prevention by the United States.

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Despite the alarming threat brought by the disease, human-to-human transmission is extremely rare as mentioned by the CDC as most of the individuals are infected by consuming contaminated food or breathing in bacteria which is most likely the case in Lanzhou.

According to Independent, the said outbreak spread from a leak at the factory of the Zhongmu Lanzhou biological pharmaceutical which happened in the middle of late July to late of August last year based on the information given out by the Health Commission of the city.

The factory of the pharmaceutical company produces Brucella vaccines for animal use, but the facility used expired sanitizers and disinfectants which means they were not able to all the bacteria that were eradicated in the waste gas.

The contaminated waste gas formed into aerosols while containing the bacteria it leaked into the air and carried by the wind-down to the Lanzhou Veterinary Institute making the area as the first spot of the outbreak.

According to a state-run news agency, the people at the institute started to report the initial infections in November and after that, it rapidly increased. Before 2019 ends, the institute already recorded 181 individuals who had been infected with brucellosis.

Among those infected patients include faculty members and Lanzhou University's students.

The outbreak even spread to the province of Heilongjiang which is located at the northeastern tip of China wherein 13 positive cases in the area had worked in the veterinarian institute way back August.

Several months after the outbreak, officials coming from the provincial and municipal levels released an investigation regarding the leak at the factory based on the Lanzhou Health Commission. By January of 2020, authorities had revoked vaccine production licenses for the facility while they withdrew the product approval numbers for its two vaccines for Brucellosis.

After the investigation, a total of seven veterinary drug product approval numbers were also canceled in the factory.

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