3245 people in Lanzhou were infected with Brucella due to pharmaceutical factory accidents. These four knowledge points need to be understood.

20 19 A public health incident of brucellosis occurred in Lanzhou. The reason is that from July 24 to August 20, Zhongmu Lanzhou Biopharmaceutical Factory used expired disinfectants in the process of producing Brucella vaccine for veterinary use. Due to incomplete disinfection, there are still bacteria in the waste gas that have not been killed. These bacteria are at a disadvantage and infect people who live and work around biopharmaceuticals.

According to the report of Health and Wellness Committee of Lanzhou City, Gansu Province on September 15, among 2 1847 people, 4,646 people were initially screened positive, and 3,245 people were confirmed positive by the provincial CDC.

The news mentioned a data that 3245 people were confirmed to be positive. Everyone knows the word positive, but what it means is not clear. Because of the global epidemic in COVID-19, many people who eat melons naturally interpret this result as "3245 people infected". This is not right. Everyone has this understanding, because COVID-19 test and brucellosis test are confused. In fact, there are two completely different detection methods, one is to check the pathogen and the other is to check the immune response in the body.

At present, the standard COVID-19 detection method is nucleic acid detection, and the target is the genetic material of the virus. If the test result is positive, it means that there is a virus in the body and the infection is in progress. But the detection method of brucellosis is to check the anti-brucellosis antibody in human blood. If it is positive, it means that the body has been infected with this bacterium before and produced antibodies, but it is not clear whether there is Brucella in the body.

If the infection of bacteria and viruses is compared to a person walking in the snow, then nucleic acid detection is to find this person, while antibody detection only sees footprints in the snow.

The answer is obvious: no.

Brucellosis, also known as lazy disease, is caused by bacterial infection. If you are infected, you can cure it with antibiotics as soon as possible.

Not all people infected with Brucella will have symptoms. Some infected people have a strong immune system and produce antibodies after bacterial invasion, killing the bacteria. If there are too many infected bacteria in the body and the human immune system can't get rid of them, acute symptoms will appear. If not treated in time, it will evolve into a chronic disease, which is a common "lazy disease" in pastoral areas.

Brucella can infect people and livestock. The clinical manifestations of brucellosis include fever, hyperhidrosis, fatigue, joint and muscle pain, lymphadenopathy, hepatosplenomegaly, testicular and epididymal enlargement in male patients and mastitis in female patients.

Can asymptomatic infected people be infected? Brucellosis is not a human-to-human disease, and infected people generally do not continue to talk about spreading germs to others. If several people in a family are infected, it is because they have been exposed to the source of infection at the same time. There are currently 3245 positive cases in Lanzhou, all of which were caused by one-time infection last year. For those who are positive, if they have had symptoms before and now have no symptoms, it means that they have recovered; If you don't have symptoms all the time, it means that you have obtained immune protection, so don't worry about sudden symptoms in the future.

It is undeniable that some patients have symptoms after infection, and if they are not treated in time, they will indeed develop into chronic symptoms or cause some chronic complications. However, from the time of infection, it is not considered that bacteria exist in patients.

There are three ways of transmission of Brucella: one is to form aerosol in the air and infect it through respiratory tract after being inhaled by people; Second, it is spread through direct contact with skin and mucous membranes. For example, workers in livestock farms and slaughterhouses directly contact sick animals during shearing and milking activities, leading to infection; The third is eating food contaminated by pathogenic bacteria, which leads to digestive tract infection.

The above-mentioned Lanzhou infection incident was an accident and an accident. In general, Brucella first infects animals, and then it is transmitted to people through animals. What needs special attention is the infection channel of "disease from mouth to mouth". For example, some people don't touch animals, but because of the pursuit of health, they are infected by drinking fresh milk (without pasteurization)! The reason is that milk will be polluted after cows are infected with germs, and not only milk, but also other dairy products will be at risk. In Dallas, Texas, USA, during the ten years from 2007 to 20 17, there were 28 cases, and 7 1% people ate cheese without high temperature sterilization. This is a living example of oral illness. So everyone should remember that eating pasteurized milk and dairy products is healthy and safe, and don't blindly pursue "fresh" milk.

The accident at Zhongmu Lanzhou Biopharmaceutical Factory caused 3245 people to be infected with Brucella. After the accident, the relevant departments punished the biopharmaceutical factory, and the approval numbers of several veterinary drug products were revoked, and eight responsible persons were dealt with. Zhongmu also said that he will actively do a good job in the aftermath and compensation.

After such punishment, can such accidents be completely avoided in the future? I do not think this is necessarily the case. At present, there are 14 manufacturers of brucellosis vaccines and veterinary drugs, among which Zhongmu, Tiankang Bio and Jinyu Group have the most complete varieties. Are other manufacturers at risk of the same or similar accidents?

Even if all manufacturers guarantee that similar mistakes will not be made again in the future, in order to truly avoid harm to public safety, we should not blindly believe the manufacturers' guarantees, but should actually consider the prevention mechanism of double insurance or even triple insurance to prevent accidents from happening again.

For example, among the more than 3,000 patients infected in the Lanzhou accident, many were residents around the pharmaceutical factory. Such enterprises with potential public health and safety risks should be located in relatively isolated industrial parks, rather than mixed in residential areas. In case of an accident, there is also a certain buffer to minimize the damage.

The same safety problem does not exist only in companies that produce brucellosis vaccines. For example, COVID-19 vaccine, two products approved for emergency use at present, are inactivated vaccines, which need to be cultured and amplified before inactivation. Biosafety is equally important in the production process.

At the same time, to implement and improve the safety measures of vaccine production, we can't just shout slogans, but also need capital investment. How to ensure that manufacturers have sufficient funds? This is also a problem. According to statistics, Jinyu Group sold 654.38 billion copies of brucellosis vaccine in 2065.438+02, but the sales income was only over 2 million yuan, with an average of only 2 cents per copy. Because the price is obviously lower than the cost, the company's production line is in a state of suspension. If the market and policies keep vaccine prices down blindly, manufacturers will not only be unable to have funds to improve safety measures, but even lead to the end that no vaccine is available, which is not conducive to the prevention of brucellosis in animal husbandry.

At present, most Brucella vaccines used are attenuated live vaccines. This vaccine is cheap, but it has strong toxicity and poor safety. The live bacteria of the vaccine remain in animals for a long time, which has a high risk of damage to the reproductive system of male animals. Dairy animals will also discharge live bacteria into emulsion for a long time, which is a hidden danger of food safety. To improve the safety of vaccines, it is necessary to develop new vaccines, which requires capital investment and market support, and cannot be implemented entirely by administrative orders.

In fact, for all drugs and vaccines, "high safety, particularly good effect and particularly low cost" is difficult to achieve at the same time.

It is a tragedy that 3245 people were infected with Brucella. However, if we don't know how to avoid similar accidents, more tragedies will happen.

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