实验动物 z-bo 2022-02-04 983

　　The occurrence of infection in laboratory animal facilities is the result of a combination of many factors. In addition to human and social factors, the characteristics of pathogenic microorganisms, the human body's sensitivity to pathogens, environmental conditions and operating methods are the four factors that affect laboratory infections. major factor. First, five direct causes of laboratory infections were discovered: ①Use a pipette to accidentally inhale infectious agents into the mouth (oral pipetting operations are currently prohibited) ②Vaccination or mistakes in the injection process, injecting personnel, ③Being affected by animals Bites, ④The injector bounces, ⑤The centrifuge accident. However, there are still many unexplained infections. Subsequent studies on microbial aerosols produced by various experimental procedures showed many traditional experimental procedures (mixing, mixing, grinding, shaking, stirring, sonication, centrifugation, etc.). Feeding animals produces aerosols, some of which can enter the human body through human breath and cause infection. According to an analysis of reported laboratory infections, 80% of "unexplainable" accidents may be caused by aerosol infection of microorganisms during surgery.

　　 When it comes to contact with the source of infection to control biological hazards (including control of indoor infection and control of the surrounding environment), the operation must be carried out in biosafety facilities and appropriate operating specifications must be strictly followed. Biosafety measures ensure the safety of workers who operate or are exposed to biological hazards, ensure that the surrounding environment is not polluted, and refer to a series of measures to ensure that they achieve their intended purpose, including design and construction, construction of laboratory equipment, use of personal protective equipment, Comply with standardized work operating procedures and control rules. I will. According to the WHO classification, the risk of biological factors can be divided into four levels.

　　 (1) Risk level I (risk group I, low-risk individuals and groups, low-risk individuals and communities)

　　Bacteria, fungi, viruses, parasites (non-pathogenic) biological factors that will not cause medical staff and animal diseases).

　　 (2) Level II risk (Level II risk, moderate personal risk, limited community risk, medium personal risk, limited community risk)

　　 may cause disease in humans or animals. Under normal circumstances, there are some harmful pathogens that will not cause serious harm to health workers, groups, livestock or the environment. Due to infection, effective treatment and preventive measures, and limited risk of transmission, laboratory exposure rarely causes serious illness.

　　 (3) The third type of risk (the third type of risk, high personal risk, low group risk, high personal risk, low community risk)

　　Severe human and animal diseases or severe economic losses caused by humans may cause losses, but they cannot cause daily contact between individuals.

　　 Pathogens that can be transmitted or treated with antibiotics and antiparasitic drugs.

　　 (4) The fourth type of risk (the fourth type of risk, high personal risk, high personal risk, high community risk)

　　 The pathogens that can cause very serious human or animal diseases are usually incurable through personal daily contact, and can easily spread directly or indirectly. Or from animals to humans and vice versa.

　　 GB194892008 "General Requirements for Laboratory Biosafety" stipulates: According to the protective measures taken against biological factors, the laboratory biosafety protection level is the lowest protection level. , The first, second, third and fourth level. , Level 4 protection is the best. A laboratory with a certain level of biosafety protection is suitable for processing microorganisms that do not cause human or animal diseases under normal circumstances; a laboratory with a certain level of biosafety protection is suitable for humans. It is suitable for operations that may cause animal and animal diseases but usually do not cause serious harm to humans, animals or the environment, the risk of infection is limited, and may be severe after laboratory infection. It rarely causes disease, and microorganisms have effective treatment and preventive measures. A laboratory with a biological safety level of 3 is suitable for operation. Cause serious diseases of humans or animals, and spread directly or indirectly between humans, animals, and animals. Relatively easy microorganisms; laboratories with biosafety protection level 4 are suitable for work that may cause very serious human and animal diseases, and microorganisms that have not been found in China or have not been announced to be eliminated.

　　Indicates that the laboratory only uses BSL-1, BSL-2, BSL-3, BSL-4 (biological safety level, BSL) for the corresponding biological safety protection level of laboratory operations. ABSL-1, ABSL-2, ABSL-3, ABSL- (Animal Biosafety Level, ABSL) represent the corresponding biosafety level of laboratories engaged in animal research. According to the activities of the laboratory, the use of personal protective equipment and the basic isolation equipment, the laboratory can be divided into the following situations:

　　Laboratories are generally regarded as non-airborne pathogenic biological agents;

　　-laboratories that can effectively use traditional safety isolation devices (such as biological safety cabinets) to manipulate traditional airborne pathogenic biological agents;

　　-Experiment on airborne pathogenic biological factors in rooms that have not been manipulated using safety isolation devices before effectively;

　　-Using a positive pressure suit with a life support system for routine operation of airborne pathogenic biological factors. If the activities of laboratory animal facilities contain pathogenic microorganisms, it is necessary to determine the level of biosafety protection based on the results of the risk assessment, improve the management system, and conduct activities in the corresponding biosafety facilities. .. For requirements, please refer to GB19489-2008 "Laboratory". General requirements for biosafety.

One of 　　. Biosafety level 1 (BSL-1) laboratory

　　Biological safety level laboratories usually have no special requirements for site selection, and are suitable for operations that will not cause humans or animals under normal circumstances. Disease microorganisms. Usually, no special barrier equipment is needed or used, and the work is done according to standard microbiological procedures. The laboratory should have technicians and supervisors who are well-trained in microbiology or related fields, and the operators should receive specialized training in laboratory procedures.

　　1. The first-level biosafety laboratory of biological risk is mainly engaged in the operation of microorganisms that do not cause human or animal diseases, so the biological risk is very limited. I will. However, certain special populations, such as pregnant women, patients with allergies and patients with certain diseases, may still be at high risk. In addition, the control of microbial contamination should be considered in terms of environmental safety and the quality of experimental results. Although many activities of the first-stage biosafety laboratory are in training and education, in terms of student education, due to the low safety awareness of students and the large number of staff, unforeseen situations may occur.

　　2. Main protective measures (1) Hardware-Hand wash basin;-Waste disinfection and disposal equipment.

　　 (2) Personal protection

　　-General protection.

　　 (3) Management

  -staff training,

　　-standard microbiological practice,

　　-good housework,

　　-General laboratory safety rules.

　　II, Level II Biosafety (BSL-2) Laboratory

　　SafetyBiological safety protection level II laboratory is suitable for processing microorganisms that may cause human or animal diseases, which are usually harmful to humans and animals. Animals or the environment do not pose a serious risk, the risk of infection is limited, serious diseases rarely occur after infection, and effective treatment and preventive measures can be taken. The main differences from the BSL-1 laboratory are: (1) manipulation of pathogenic microorganisms, (2) various types of experimental activities, (3) the possibility of laboratory infection is high, and the results are usually not serious.

　　1. Biological risk

　　 For the biological safety of microorganisms that cause human or animal diseases, there are biological risks in the operation of secondary laboratories. In addition, there are many laboratories, many jobs, complex work types, complicated samples, numerous employees, many unknown factors, relatively low safety awareness, and possible biosafety accidents. This is the most reliable laboratory. According to statistics, unexplained infections account for more than 80% of reported incidents. Hand infections (including infections caused by direct or indirect contamination of other parts) and respiratory infections may be the most important risks. Risk II pathogens can cause varying degrees of damage to individuals and even cause death. Due to the complexity of the sample, there may be unknown or high-risk pathogens and may cause serious consequences, such as human-to-human transmission. For example, the SARS virus infection incident of a certain research institute in Beijing occurred in the secondary biosafety research institute.

　　2. Main protective measures (1) Hardware-Hand washing sink;-Waste disinfection (high-pressure steam) and disposal equipment;-Barrier equipment (such as biological safety cabinets).

　　 (2) Personal protection

　　-General protection, but need to be evaluated.

　　 (3) Management

　　-Experimental personnel should receive special training in microbial treatment;

　　-Should have well-trained technicians and supervisors in microbiology or related fields

　　-Standard microbial treatment standards,

　　-proper housekeeping,

　　-restrict laboratory access when conducting experiments,

　　-Laboratory access control,

　　-Lab

　　'S general safety regulations-establish a safety management system.

  three. Biosafety Level 3 Laboratory (BSL-3)

　　 Biosafety Level 3 laboratory is suitable for processing microorganisms that may cause serious human or animal diseases, such as direct or indirect microorganisms. It may be between people, between animals and people, between animals and animals. Compared with the first-level and second-level biosafety laboratories, the third-level biosafety laboratory is a higher-level protection laboratory, and its management and technical requirements are higher than those for the first and second-level laboratories.

　　1, biological risk

　　An important feature of microorganisms with high risk levels is that they are very common, harmful and highly pathogenic microorganisms. Infection can seriously endanger people's health and lives, cause social panic, and may cause major losses. A typical example is the SARS virus infection in a laboratory in Beijing in 2004. According to reports, the cause of the incident was that the researchers removed an inactivated virus from the third-level biosafety laboratory and infected it while continuing to operate the virus laboratory with normal protection levels. .. Although it is difficult to avoid infections caused by dangerous microorganisms in actual work, from a control point of view, this is an unacceptable danger. Therefore, governments of various countries strictly control laboratories engaged in work related to highly pathogenic microorganisms, and their facilities, equipment, personnel, management systems and work content must meet the requirements of the regulations. And must meet the standards.

From the perspective of laboratory activities, there is no essential difference between the third and second biosafety laboratories, but the psychological pressure of the personnel is higher and the operational flexibility is reduced (safety protection requirements and psychological pressure are both influencing factors. From From the perspective of the target, the risk level is higher, but the source and target microorganisms in the sample are usually more accurate. In terms of equipment and equipment, personal protection, personnel and management system requirements, it is much higher than the secondary biosafety laboratory. Most pathogenic organisms of hazard level III are relatively difficult to protect because they are spread through respiratory aerosols.

　　 We have conducted a statistical analysis of the available data. The infection rate of the third-level biosafety laboratory is lower than that of the second-level biosafety laboratory, but the impact is greater.

　　2, key protection measures

　　 (1) Hardware

　　-Hand washing sink/hand washing equipment;

　　-Waste disinfection (high pressure steam) and treatment equipment;

　　-barrier equipment (such as biological safety cabinets);

　　-barrier equipment;

　　-Air flow control;

　　-High efficiency air particle filter equipment;

  -Video Surveillance;

　　-Safety system.

　　 (2) Personal protection

　　-Special protection.

　　 (3) Management

　　-Experimental personnel should receive special training in microbial treatment;

　　-Should have technicians and supervisors who have received good training in microbiology or related fields

　　———Work experience in secondary laboratory of biosafety;

　　-Special microbiological practices;

　　-Excellent housekeeping management;

　　-General laboratory safety rules;

　　-Allowed to enter the laboratory;

　　-Safety management system.

　　The fourth biosafety level 4 (BSL-4) laboratory

　　 Biosafety Level 4 laboratory, a kind of manipulation of microorganisms that may cause very serious human and animal diseases, is still found in China to be suitable for the treatment of microorganisms that have not been declared or have not been declared to be excluded. Highly pathogenic microorganisms are currently the world's highest level of biosafety protection laboratory.

　　1. The microorganisms of biological risk IV are the most dangerous pathogenic microorganisms currently known or unknown to humans. They have strong infectious power and high mortality after infection. For example, variola virus has high viability, is easily spread by aerosol, is highly toxic, and was once a disaster for humans. After research and efforts, mankind announced in 1980 that the variola virus was eliminated on a global scale (but the designated unit retained the variola virus strain). This is an indelible contribution of the biosafety laboratory. Unfortunately, in the research process There are many laboratory-related infections. In August 1978, the laboratory at the University of Birmingham in the United Kingdom was unable to take effective defensive measures, causing the smallpox virus to contaminate the laboratory, resulting in the death and infection of a female employee. The father learned that his daughter had contracted the smallpox virus and died of a heart attack. Immediately, the chief professor of the laboratory, Henry Bedson (Henry Bedson) committed suicide and investigated more than 300 close contacts. The biological risk is so high that it is necessary to ensure that personnel and operating objects are engaged in related work, and to establish a reliable separation operating system between humans and microorganisms. Have. To ensure environmental safety, a two-layer HEPA filter should be used to treat exhaust gas, and all waste should be disinfected and removed from the laboratory.

　　2, key protection measures

　　 (1) Hardware

　　-Hand washing sink/hand washing equipment;

　　-Waste disinfection (high pressure steam) and treatment equipment;

　　-barrier equipment (such as biological safety cabinets);

　　-barrier facilities with clear air tightness requirements;

　　-Air flow control;

　　-Double high-efficiency air particle filter device;

　　--——Life support system (when using positive pressure clothes)

  -Video Surveillance;

　　-Safety system.

　　 (2) Personal protection

　　 Pressure protective clothing;

　　Special protection (the operator and the operating object must be completely isolated. For example, when using a level 3 biological safety cabinet, positive pressure clothing is not required).

　　 (3) Management

　　-Experimental personnel should receive special training in microbial treatment;

　　-Should have technicians and supervisors who have received good training in microbiology or related fields

　　———Work experience in the third laboratory of biosafety,

　　-Special selection and evaluation procedures for operators,

　　-Special microbiological practices,

　　-correct housekeeping,

　　-General laboratory safety rules.

　　-Access to the laboratory;

　　-Safety management system.

　　5. Animal biosafety laboratory (ABSL-1, -2, -3 or -4)

　　Animal The so-called animal biosafety laboratory refers to the biosafety laboratory including operations, and the safety protection level corresponds to the BSL laboratory. For small animals with well-designed and effective isolation and laboratory equipment, the management and technical requirements of the biosafety laboratory are basically the same as the corresponding level of the BSL laboratory. If the basic isolation device cannot be used effectively, the breeding facility must serve as the basic isolation device. Another issue to consider is that operators need to enter the breeding facility to directly face the infected animals. Therefore, the design and construction requirements of this type of ABSL laboratory are significantly higher than the corresponding BSL laboratory.

　　 When working with invertebrates, especially small animals with fast flying or moving bodies, special designs (such as cooling) should be used as needed to control the animals used in the experiment. Have.

　　 1. Compared with the main biological risks of BSL laboratories, the biological risks of ABSL laboratories should also be considered.

　　-the natural characteristics of animals, such as aggressiveness, grip and chewiness, lifestyle;

　　-Animal hair, breathing gas and excrement, etc., require special attention to the formation of harmful aerosols. ..

　　-susceptible to animal diseases;

　　-Potential allergen transmission;

　　-the availability and effectiveness of reproduction and operation of animal barrier equipment,

　　-naturally occurring internal and external parasites,

　　-Animal escape,

　　-processing and disposal of animal carcasses and other waste,

　　-Does it infect humans at the same time,

　　-Reduced requirements when dealing with pathogens that do not infect humans. , To remove pathogens from the laboratory.

　　2, main protection measures

　　 Compared with the BSL laboratory, all the protective measures of the ABSL laboratory must be designed for the working animals. Particular attention should be paid to controlling harmful aerosols, preventing animal bites and disposing of waste (including animal carcasses and feces). Wait)

　　 (1) Hardware

　　-animal isolators, cages, fences, etc., to protect the operator, protect the environment and prevent animals from escaping;

　　-animal handling equipment, restraint equipment, etc.;

　　Animal transfer equipment;

　　 Animal carcasses and waste disinfection, treatment and disposal equipment;

　　Effective isolation facilities for raising large animals;

　　 Forced shower.

　　 (2) Personal protective equipment

　　-suitable for handling experimental animals, such as scratch resistance, splash resistance and aerosol resistance.

　　 (3) Management

  -staff training;

　　-Laboratory animal good practices and special practices;

　　-Laboratory animal good care practices;

　　-Animal experiment ethics and welfare standards;

　　-Safety management system.