Infection prevention and control

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Infection_prevention_and_control 

 

Infection prevention and control is the discipline concerned with preventing healthcare-associated infections; a practical rather than academic sub-discipline of epidemiology. In Northern Europe, infection prevention and control is expanded from healthcare into a component in public health, known as "infection protection" (smittevern, smittskydd, Infektionsschutz) in the local languages. It is an essential part of the infrastructure of health care. Infection control and hospital epidemiology are akin to public health practice, practiced within the confines of a particular health-care delivery system rather than directed at society as a whole. Anti-infective agents include antibiotics, antibacterials, antifungals, antivirals and antiprotozoals.

Infection control addresses factors related to the spread of infections within the healthcare setting, whether among patients, from patients to staff, from staff to patients, or among staff. This includes preventive measures such as hand washing, cleaning, disinfecting, sterilizing, and vaccinating. Other aspects include surveillance, monitoring, and investigating any suspected outbreak of infection, and its management.

The World Health Organization (WHO) has set up an Infection Prevention and Control (IPC) unit in its Service Delivery and Safety department that publishes related guidelines.

Infection prevention and control

Aseptic technique is a key component of all invasive medical procedures. Similar control measures are also recommended in any healthcare setting to prevent the spread of infection generally.

Hand hygiene

Independent studies by Ignaz Semmelweis in 1846 in Vienna and Oliver Wendell Holmes, Sr. in 1843 in Boston established a link between the hands of health care workers and the spread of hospital-acquired disease. The U.S. Centers for Disease Control and Prevention (CDC) state that “It is well documented that the most important measure for preventing the spread of pathogens is effective handwashing.” In the developed world, hand washing is mandatory in most health care settings and required by many different regulators.

In the United States, OSHA standards require that employers must provide readily accessible hand washing facilities, and must ensure that employees wash hands and any other skin with soap and water or flush mucous membranes with water as soon as feasible after contact with blood or other potentially infectious materials (OPIM). 

In the UK healthcare professionals have adopted the 'Ayliffe Technique', based on the 6 step method developed by Graham Ayliffe, JR Babb and AH Quoraishi.

Mean percentage changes in bacterial numbers

Method used	Change in bacteria present
Paper towels (2-ply 100% recycled).	- 48.4%
Paper towels (2-ply through-air dried, 50% recycled)	- 76.8%
Warm air dryer	+ 254.5%
Jet air dryer	+ 14.9%

Drying is an essential part of the hand hygiene process. In November 2008, a non-peer-reviewed study was presented to the European Tissue Symposium by the University of Westminster, London, comparing the bacteria levels present after the use of paper towels, warm air hand dryers, and modern jet-air hand dryers. Of those three methods, only paper towels reduced the total number of bacteria on hands, with "through-air dried" towels the most effective.

The presenters also carried out tests to establish whether there was the potential for cross-contamination of other washroom users and the washroom environment as a result of each type of drying method. They found that:

• the jet air dryer, which blows air out of the unit at claimed speeds of 400 mph, was capable of blowing micro-organisms from the hands and the unit and potentially contaminating other washroom users and the washroom environment up to 2 metres away
• use of a warm air hand dryer spread micro-organisms up to 0.25 metres from the dryer
• paper towels showed no significant spread of micro-organisms.

In 2005, in a study conducted by TUV Produkt und Umwelt, different hand drying methods were evaluated. The following changes in the bacterial count after drying the hands were observed: 

Drying method	Effect on bacterial count
Paper towels and roll	Decrease of 24%
Hot-air drier	Increase of 117%

Sterilization

Sterilization is a process intended to kill all microorganisms and is the highest level of microbial kill that is possible. Sterilizers may be heat only, steam, or liquid chemical. Effectiveness of the sterilizer, for example a steam autoclave is determined in three ways. First, mechanical indicators and gauges on the machine itself indicate proper operation of the machine. Second heat sensitive indicators or tape on the sterilizing bags change color which indicate proper levels of heat or steam. And, third (most importantly) is biological testing in which a microorganism that is highly heat and chemical resistant (often the bacterial endospore) is selected as the standard challenge. If the process kills this microorganism, the sterilizer is considered to be effective.

Sterilization, if performed properly, is an effective way of preventing bacteria from spreading. It should be used for the cleaning of the medical instruments or gloves, and basically any type of medical item that comes into contact with the blood stream and sterile tissues.

There are four main ways in which such items can be sterilized: autoclave (by using high-pressure steam), dry heat (in an oven), by using chemical sterilants such as glutaraldehydes or formaldehyde solutions or by radiation (with the help of physical agents). The first two are the most used methods of sterilizations mainly because of their accessibility and availability. Steam sterilization is one of the most effective types of sterilizations, if done correctly which is often hard to achieve. Instruments that are used in health care facilities are usually sterilized with this method. The general rule in this case is that in order to perform an effective sterilization, the steam must get into contact with all the surfaces that are meant to be disinfected. On the other hand, dry heat sterilization, which is performed with the help of an oven, is also an accessible type of sterilization, although it can only be used to disinfect instruments that are made of metal or glass. The very high temperatures needed to perform sterilization in this way are able to melt the instruments that are not made of glass or metal.

Steam sterilization is done at a temperature of 121 C (250 F) with a pressure of 209 kPa (15 lbs/in2). In these conditions, rubber items must be sterilized for 20 minutes, and wrapped items 134 C with pressure of 310 kPa for 7 minutes. The time is counted once the temperature that is needed has been reached. Steam sterilization requires four conditions in order to be efficient: adequate contact, sufficiently high temperature, correct time and sufficient moisture. Sterilization using steam can also be done at a temperature of 132 C (270 F), at a double pressure. Dry heat sterilization is performed at 170 C (340 F) for one hour or two hours at a temperature of 160 C (320 F). Dry heat sterilization can also be performed at 121 C, for at least 16 hours.

Chemical sterilization, also referred to as cold sterilization, can be used to sterilize instruments that cannot normally be disinfected through the other two processes described above. The items sterilized with cold sterilization are usually those that can be damaged by regular sterilization. Commonly, glutaraldehydes and formaldehyde are used in this process, but in different ways. When using the first type of disinfectant, the instruments are soaked in a 2–4% solution for at least 10 hours while a solution of 8% formaldehyde will sterilize the items in 24 hours or more. Chemical sterilization is generally more expensive than steam sterilization and therefore it is used for instruments that cannot be disinfected otherwise. After the instruments have been soaked in the chemical solutions, they are mandatory to be rinsed with sterile water which will remove the residues from the disinfectants. This is the reason why needles and syringes are not sterilized in this way, as the residues left by the chemical solution that has been used to disinfect them cannot be washed off with water and they may interfere with the administered treatment. Although formaldehyde is less expensive than glutaraldehydes, it is also more irritating to the eyes, skin and respiratory tract and is classified as a potential carcinogen.

Other sterilization methods exist, though their efficiency is still controversial. These methods include gas, UV, gas plasma, and chemical sterilization with agents such as peroxyacetic acid or paraformaldehyde.

Cleaning

Infections can be prevented from occurring in homes as well. In order to reduce their chances to contract an infection, individuals are recommended to maintain a good hygiene by washing their hands after every contact with questionable areas or bodily fluids and by disposing of garbage at regular intervals to prevent germs from growing.

Disinfection

Disinfection uses liquid chemicals on surfaces and at room temperature to kill disease causing microorganisms. Ultraviolet light has also been used to disinfect the rooms of patients infected with Clostridium difficile after discharge. Disinfection is less effective than sterilization because it does not kill bacterial endospores.

Personal protective equipment

Disposable PPE

Personal protective equipment (PPE) is specialized clothing or equipment worn by a worker for protection against a hazard. The hazard in a health care setting is exposure to blood, saliva, or other bodily fluids or aerosols that may carry infectious materials such as Hepatitis C, HIV, or other blood borne or bodily fluid pathogen. PPE prevents contact with a potentially infectious material by creating a physical barrier between the potential infectious material and the healthcare worker.

The United States Occupational Safety and Health Administration (OSHA) requires the use of personal protective equipment (PPE) by workers to guard against blood borne pathogens if there is a reasonably anticipated exposure to blood or other potentially infectious materials.

Components of PPE include gloves, gowns, bonnets, shoe covers, face shields, CPR masks, goggles, surgical masks, and respirators. How many components are used and how the components are used is often determined by regulations or the infection control protocol of the facility in question. Many or most of these items are disposable to avoid carrying infectious materials from one patient to another patient and to avoid difficult or costly disinfection. In the US, OSHA requires the immediate removal and disinfection or disposal of a worker's PPE prior to leaving the work area where exposure to infectious material took place.

The inappropriate use of PPE equipment such as gloves, has been linked to an increase in rates of the transmission of infection, and the use of such must be compatible with the other particular hand hygiene agents used.

Vaccination of health care workers

Health care workers may be exposed to certain infections in the course of their work. Vaccines are available to provide some protection to workers in a healthcare setting. Depending on regulation, recommendation, the specific work function, or personal preference, healthcare workers or first responders may receive vaccinations for hepatitis B; influenza; measles, mumps and rubella; Tetanus, diphtheria, pertussis; N. meningitidis; and varicella.

Surveillance for infections

Surveillance is the act of infection investigation using the CDC definitions. Determining the presence of a hospital acquired infection requires an infection control practitioner (ICP) to review a patient's chart and see if the patient had the signs and symptom of an infection. Surveillance definitions exist for infections of the bloodstream, urinary tract, pneumonia, surgical sites and gastroenteritis. 

Surveillance traditionally involved significant manual data assessment and entry in order to assess preventative actions such as isolation of patients with an infectious disease. Increasingly, computerized software solutions are becoming available that assess incoming risk messages from microbiology and other online sources. By reducing the need for data entry, software can reduce the data workload of ICPs, freeing them to concentrate on clinical surveillance.

As of 1998, approximately one third of healthcare acquired infections were preventable. Surveillance and preventative activities are increasingly a priority for hospital staff. The Study on the Efficacy of Nosocomial Infection Control (SENIC) project by the U.S. CDC found in the 1970s that hospitals reduced their nosocomial infection rates by approximately 32 per cent by focusing on surveillance activities and prevention efforts.

Isolation and quarantine

In healthcare facilities, medical isolation refers to various physical measures taken to interrupt nosocomial spread of contagious diseases. Various forms of isolation exist, and are applied depending on the type of infection and agent involved, and its route of transmission , to address the likelihood of spread via airborne particles or droplets, by direct skin contact, or via contact with body fluids.

In cases where infection is merely suspected, individuals may be quarantined until the incubation period has passed and the disease manifests itself or the person remains healthy. Groups may undergo quarantine, or in the case of communities, a cordon sanitaire may be imposed to prevent infection from spreading beyond the community, or in the case of protective sequestration, into a community. Public health authorities may implement other forms of social distancing, such as school closings, when needing to control an epidemic.

Outbreak investigation

When an unusual cluster of illness is noted, infection control teams undertake an investigation to determine whether there is a true disease outbreak, a pseudo-outbreak (a result of contamination within the diagnostic testing process), or just random fluctuation in the frequency of illness. If a true outbreak is discovered, infection control practitioners try to determine what permitted the outbreak to occur, and to rearrange the conditions to prevent ongoing propagation of the infection. Often, breaches in good practice are responsible, although sometimes other factors (such as construction) may be the source of the problem.

Outbreaks investigations have more than a single purpose. These investigations are carried out in order to prevent additional cases in the current outbreak, prevent future outbreaks, learn about a new disease or learn something new about an old disease. Reassuring the public, minimizing the economic and social disruption as well as teaching epidemiology are some other obvious objectives of outbreak investigations.

According to the WHO, outbreak investigations are meant to detect what is causing the outbreak, how the pathogenic agent is transmitted, where it all started from, what is the carrier, what is the population at risk of getting infected and what are the risk factors.

Training in infection control and health care epidemiology

Practitioners can come from several different educational streams. Many begin as nurses, some as medical technologists (particularly in clinical microbiology), and some as physicians (typically infectious disease specialists). Specialized training in infection control and health care epidemiology are offered by the professional organizations described below. Physicians who desire to become infection control practitioners often are trained in the context of an infectious disease fellowship.

In the United States, Certification Board of Infection Control and Epidemiology is a private company that certifies infection control practitioners based on their educational background and professional experience, in conjunction with testing their knowledge base with standardized exams. The credential awarded is CIC, Certification in Infection Control and Epidemiology. It is recommended that one has 2 years of Infection Control experience before applying for the exam. Certification must be renewed every five years.

A course in hospital epidemiology (infection control in the hospital setting) is offered jointly each year by the Centers for Disease Control and Prevention (CDC) and the Society for Healthcare Epidemiology of America.

Standardization

Australia

In 2002, the Royal Australian College of General Practitioners published a revised standard for office-based infection control which covers the sections of managing immunisation, sterilisation and disease surveillance. However, the document on the personal hygiene of health workers is only limited to hand hygiene, waste and linen management, which may not be sufficient since some of the pathogens are air-born and could be spread through air flow.

Since November 1st 2019, the Australian Commission on Safety and Quality in Health Care has managed the Hand Hygiene initiative in Australia, an initiative focused on improving hand hygiene practices to reduce the incidence of healthcare associated infections. 

United States

Currently, the federal regulation that describes infection control standards, as related to occupational exposure to potentially infectious blood and other materials, is found at 29 CFR Part 1910.1030 Bloodborne pathogens.

Drug resistance

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Drug_resistance 

An illustrative diagram explaining drug resistance.

Drug resistance is the reduction in effectiveness of a medication such as an antimicrobial or an antineoplastic in treating a disease or condition. The term is used in the context of resistance that pathogens or cancers have "acquired", that is, resistance has evolved. Antimicrobial resistance and antineoplastic resistance challenge clinical care and drive research. When an organism is resistant to more than one drug, it is said to be multidrug-resistant.

The development of antibiotic resistance in particular stems from the drugs targeting only specific bacterial molecules (almost always proteins). Because the drug is so specific, any mutation in these molecules will interfere with or negate its destructive effect, resulting in antibiotic resistance. Furthermore, there is mounting concern over the abuse of antibiotics in the farming of livestock, which in the European Union alone accounts for three times the volume dispensed to humans – leading to development of super-resistant bacteria.

Bacteria are capable of not only altering the enzyme targeted by antibiotics, but also by the use of enzymes to modify the antibiotic itself and thus neutralize it. Examples of target-altering pathogens are Staphylococcus aureus, vancomycin-resistant enterococci and macrolide-resistant Streptococcus, while examples of antibiotic-modifying microbes are Pseudomonas aeruginosa and aminoglycoside-resistant Acinetobacter baumannii.

In short, the lack of concerted effort by governments and the pharmaceutical industry, together with the innate capacity of microbes to develop resistance at a rate that outpaces development of new drugs, suggests that existing strategies for developing viable, long-term anti-microbial therapies are ultimately doomed to failure. Without alternative strategies, the acquisition of drug resistance by pathogenic microorganisms looms as possibly one of the most significant public health threats facing humanity in the 21st century.

Types

Resistance to chemicals is only one aspect of the problem, another being resistance to physical factors such as temperature, pressure, sound, radiation and magnetism, and not discussed in this article, but found at Physical factors affecting microbial life. 

Drug, toxin, or chemical resistance is a consequence of evolution and is a response to pressures imposed on any living organism. Individual organisms vary in their sensitivity to the drug used and some with greater fitness may be capable of surviving drug treatment. Drug-resistant traits are accordingly inherited by subsequent offspring, resulting in a population that is more drug-resistant. Unless the drug used makes sexual reproduction or cell-division or horizontal gene transfer impossible in the entire target population, resistance to the drug will inevitably follow. This can be seen in cancerous tumors where some cells may develop resistance to the drugs used in chemotherapy. Chemotherapy causes fibroblasts near tumors to produce large amounts of the protein WNT16B. This protein stimulates the growth of cancer cells which are drug-resistant. MicroRNAs have also been shown to affect acquired drug resistance in cancer cells and this can be used for therapeutic purposes. Malaria in 2012 has become a resurgent threat in South East Asia and sub-Saharan Africa, and drug-resistant strains of Plasmodium falciparum are posing massive problems for health authorities. Leprosy has shown an increasing resistance to dapsone.

A rapid process of sharing resistance exists among single-celled organisms, and is termed horizontal gene transfer in which there is a direct exchange of genes, particularly in the biofilm state. A similar asexual method is used by fungi and is called "parasexuality". Examples of drug-resistant strains are to be found in microorganisms such as bacteria and viruses, parasites both endo- and ecto-, plants, fungi, arthropods, mammals, birds, reptiles, fish, and amphibians.

In the domestic environment, drug-resistant strains of organism may arise from seemingly safe activities such as the use of bleach, tooth-brushing and mouthwashing, the use of antibiotics, disinfectants and detergents, shampoos, and soaps, particularly antibacterial soaps, hand-washing, usurface sprays, application of deodorants, sunblocks and any cosmetic or health-care product, insecticides, and dips. The chemicals contained in these preparations, besides harming beneficial organisms, may intentionally or inadvertently target organisms that have the potential to develop resistance.

Mechanisms

The four main mechanisms by which microorganisms exhibit resistance to antimicrobials are:

1. Drug inactivation or modification: e.g., enzymatic deactivation of Penicillin G in some penicillin-resistant bacteria through the production of β-lactamases.
2. Alteration of target site: e.g., alteration of PBP — the binding target site of penicillins — in MRSA and other penicillin-resistant bacteria.
3. Alteration of metabolic pathway: e.g., some sulfonamide-resistant bacteria do not require para-aminobenzoic acid (PABA), an important precursor for the synthesis of folic acid and nucleic acids in bacteria inhibited by sulfonamides. Instead, like mammalian cells, they turn to utilizing preformed folic acid.
4. Reduced drug accumulation: by decreasing drug permeability and/or increasing active efflux (pumping out) of the drugs across the cell surface.

Mechanisms of Acquired Drug Resistance:

Mechanism	Antimicrobial Agent	Drug Action	Mechanism of Resistance
Destroy drug	Aminoglycoside Beta-lactam antibiotics (penicillin and cephalosporin) Chloramphenicol	Binds to 30S Ribosome subunit, inhibiting protein synthesis Binds to penicillin-binding proteins, Inhibiting peptidoglycan synthesis Bind to 50S ribosome subunit, inhibiting formation of peptide bonds	Plasmid encode enzymes that chemically alter the drug (e.g., by acetylation or phosphorylation), thereby inactivating it. Plasmid encode beta-lactamase, which open the beta-lactam ring, inactivating it. Plasmid encode an enzyme that acetylate the drug, thereby inactivating it.
Alters drug target	Aminoglycosides Beta-lactam antibiotics (penicillin and cephalosporin) Erythromycin Quinolones Rifampin Trimethoprim	Binds to 30S Ribosome subunit, inhibiting protein synthesis Binds to penicillin-binding proteins, Inhibiting peptidoglycan synthesis Bind to 50S ribosome subunit, inhibiting protein synthesis Binds to DNA topoisomerase, an enzyme essential for DNA synthesis Binds to the RNA polymerase; inhibiting initiation of RNA synthesis Inhibit the enzyme dihydrofolate reduces, blocking the folic acid pathway	Bacteria make an altered 30S ribosomes that does not bind to the drug. Bacteria make an altered penicillin-binding proteins, that do not bind to the drug. Bacteria make a form of 50S ribosome that does not binds to the drug. Bacteria make an altered DNA topoisomerase that does not binds to the drug. Bacteria make an altered polymerase that does not binds to the drug. Bacteria make an altered enzyme that does not binds to the drug.
Inhibits drug entry or removes drug	Penicillin Erythromycin Tetracycline	Binds to penicillin-binding proteins, Inhibiting peptidoglycan synthesis Bind to 50S ribosome subunit, inhibiting protein synthesis Binds to 30S Ribosome subunit, inhibiting protein synthesis by blocking tRNA	Bacteria change shape of the outer membrane porin proteins, preventing drug from entering cell. New membrane transport system prevent drug from entering cell. New membrane transport system pumps drug out of cell.

Metabolic cost

Biological cost is a measure of the increased energy metabolism required to achieve a function.

Drug resistance has a high metabolic price in pathogens for which this concept is relevant (bacteria, endoparasites, and tumor cells.) In viruses, an equivalent "cost" is genomic complexity. The high metabolic cost means that, in the absence of antibiotics, a resistant pathogen will have decreased evolutionary fitness as compared to susceptible pathogens. This is one of the reasons drug resistance adaptations are rarely seen in environments where antibiotics are absent. However, in the presence of antibiotics, the survival advantage conferred off-sets the high metabolic cost and allows resistant strains to proliferate.

Treatment

In humans, the gene ABCB1 encodes MDR1(p-glycoprotein) which is a key transporter of medications on the cellular level. If MDR1 is overexpressed, drug resistance increases. Therefore, ABCB1 levels can be monitored. In patients with high levels of ABCB1 expression, the use of secondary treatments, like metformin, have been used in conjunction with the primary drug treatment with some success.

For antibiotic resistance, which represents a widespread problem nowadays, drugs designed to block the mechanisms of bacterial antibiotic resistance are used. For example, bacterial resistance against beta-lactam antibiotics (such as penicillin and cephalosporins) can be circumvented by using antibiotics such as nafcillin that are not susceptible to destruction by certain beta-lactamases (the group of enzymes responsible for breaking down beta-lactams). Beta-lactam bacterial resistance can also be dealt with by administering beta-lactam antibiotics with drugs that block beta-lactamases such as clavulanic acid so that the antibiotics can work without getting destroyed by the bacteria first. Recently, researchers have recognized the need for new drugs that inhibit bacterial efflux pumps, which cause resistance to multiple antibiotics such as beta-lactams, quinolones, chloramphenicol, and trimethoprim by sending molecules of those antibiotics out of the bacterial cell. Sometimes a combination of different classes of antibiotics may be used synergistically; that is, they work together to effectively fight bacteria that may be resistant to one of the antibiotics alone.

Destruction of the resistant bacteria can also be achieved by phage therapy, in which a specific bacteriophage (virus that kills bacteria) is used.

There is research being done using antimicrobial peptides. In the future, there is a possibility that they might replace novel antibiotics.

Biological hazard

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Biological_hazard 

The biohazard symbol

A biological hazard, or biohazard, is a biological substance that poses a threat to the health of living organisms, primarily humans. This could include a sample of a microorganism, virus or toxin that can adversely affect human health. A biohazard could also be a substance harmful to other animals.

The term and its associated symbol are generally used as a warning, so that those potentially exposed to the substances will know to take precautions. The biohazard symbol was developed in 1966 by Charles Baldwin, an environmental-health engineer working for the Dow Chemical Company on the containment products.

It is used in the labeling of biological materials that carry a significant health risk, including viral samples and used hypodermic needles.

In Unicode, the biohazard symbol is U+2623 (☣).

Classification

Bio hazardous agents are classified for transportation by UN number:

• Category A, UN 2814 – Infectious substance, affecting humans: An infectious substance in a form capable of causing permanent disability or life-threatening or fatal disease in otherwise healthy humans or animals when exposure to it occurs.
• Category A, UN 2900 – Infectious substance, affecting animals (only): An infectious substance that is not in a form generally capable of causing permanent disability or life-threatening or fatal disease in otherwise healthy humans and animals when exposure to themselves occurs.
• Category B, UN 3373 – Biological substance transported for diagnostic or investigative purposes.
• Regulated Medical Waste, UN 3291 – Waste or reusable material derived from medical treatment of an animal or human, or from biomedical research, which includes the production and testing.

Levels of biohazard

Immediate disposal of used needles into a sharps container is standard procedure.

 

NHS medics practice using protective equipment used when treating Ebola patients

The United States Centers for Disease Control and Prevention (CDC) categorizes various diseases in levels of biohazard, Level 1 being minimum risk and Level 4 being extreme risk. Laboratories and other facilities are categorized as BSL (Biosafety Level) 1–4 or as P1 through P4 for short (Pathogen or Protection Level).

• Biohazard Level 1: Bacteria and viruses including Bacillus subtilis, canine hepatitis, Escherichia coli, and varicella (chicken pox), as well as some cell cultures and non-infectious bacteria. At this level precautions against the biohazardous materials in question are minimal, most likely involving gloves and some sort of facial protection.
• Biohazard Level 2: Bacteria and viruses that cause only mild disease to humans, or are difficult to contract via aerosol in a lab setting, such as hepatitis A, B, and C, some influenza A strains, Lyme disease, salmonella, mumps, measles, scrapie, dengue fever, and HIV. Routine diagnostic work with clinical specimens can be done safely at Biosafety Level 2, using Biosafety Level 2 practices and procedures. Research work (including co-cultivation, virus replication studies, or manipulations involving concentrated virus) can be done in a BSL-2 (P2) facility, using BSL-3 practices and procedures.
• Biohazard Level 3: Bacteria and viruses that can cause severe to fatal disease in humans, but for which vaccines or other treatments exist, such as anthrax, West Nile virus, Venezuelan equine encephalitis, SARS virus, MERS coronavirus, hantaviruses, tuberculosis, typhus, Rift Valley fever, Rocky Mountain spotted fever, yellow fever, and malaria.
• Biohazard Level 4: Viruses that cause severe to fatal disease in humans, and for which vaccines or other treatments are not available, such as Bolivian hemorrhagic fever, Marburg virus, Ebola virus, Lassa fever virus, Crimean–Congo hemorrhagic fever, and other hemorrhagic diseases. Variola virus (smallpox) is an agent that is worked with at BSL-4 despite the existence of a vaccine, as it has been eradicated. When dealing with biological hazards at this level, the use of a positive pressure personnel suit with a segregated air supply is mandatory. The entrance and exit of a Level Four biolab will contain multiple showers, a vacuum room, an ultraviolet light room, autonomous detection system, and other safety precautions designed to destroy all traces of the biohazard. Multiple airlocks are employed and are electronically secured to prevent doors from both opening at the same time. All air and water service going to and coming from a Biosafety Level 4 (P4) lab will undergo similar decontamination procedures to eliminate the possibility of an accidental release. Currently there are no bacteria classified at this level.

Symbol

☣
Biological hazard
In Unicode	U+2623 ☣ BIOHAZARD SIGN (HTML ☣)
Related
See also	U+2622 ☢ RADIOACTIVE SIGN (HTML ☢)

The biohazard symbol was developed by the Dow Chemical Company in 1966 for their containment products. According to Charles Baldwin, an environmental-health engineer who contributed to its development: "We wanted something that was memorable but meaningless, so we could educate people as to what it means." In an article he wrote for Science in 1967, the symbol was presented as the new standard for all biological hazards ("biohazards"). The article explained that over 40 symbols were drawn up by Dow artists, and all of the symbols investigated had to meet a number of criteria:

1. Striking in form in order to draw immediate attention;
2. Unique and unambiguous, in order not to be confused with symbols used for other purposes;
3. Quickly recognizable and easily recalled;
4. Symmetric, in order to appear identical from all angles of approach;
5. Acceptable to groups of varying ethnic backgrounds.

The chosen symbol scored the best on nationwide testing for memorability.

The design was first specified in 39 FR 23680 but was dropped in the succeeding amendment. However, various US states adopted the specification for their state code.

Wildlife smuggling and zoonoses

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Wildlife_smuggling_and_zoonoses 

 

Wildlife poachers assembling tusks for ivory trade

 

The possibilities for zoonotic disease transmissions

Wildlife trafficking practices have resulted in the emergence of zoonotic diseases. Exotic wildlife trafficking is a multi-billion dollar industry that involves the removal and shipment of mammals, reptiles, amphibians, invertebrates, and fish all over the world. Traded wild animals are used for bushmeat consumption, unconventional exotic pets, animal skin clothing accessories, home trophy decorations, privately owned zoos, and for traditional medicine practices. Dating back centuries, people from Africa, Asia, Latin America, the Middle East, and Europe have used animal bones, horns, or organs for their believed healing effects on the human body. Wild tigers, rhinos, elephants, pangolins, and certain reptile species are acquired through legal and illegal trade operations in order to continue these historic cultural healing practices. Within the last decade nearly 975 different wild animal taxa groups have been legally and illegally exported out of Africa and imported into areas like China, Japan, Indonesia, the United States, Russia, Europe, and South America.

Consuming or owning exotic animals can propose unexpected and dangerous health risks. A number of animals, wild or domesticated, carry infectious diseases and approximately 75% of wildlife diseases are vector-borne viral zoonotic diseases. Zoonotic diseases are complex infections residing in animals and can be transmitted to humans. The emergence of zoonotic diseases usually occurs in three stages. Initially the disease is spread through a series of spillover events between domesticated and wildlife populations living in close quarters. Diseases then spread through series of direct contact methods, indirect contact methods, contaminated foods, or vector-borne transmissions. After one of these transmission methods occurs, the disease then rises exponentially in human populations living in close proximities. After the appearance of the COVID-19 pandemic, said to have originated by this method at Huanan Seafood Wholesale Market in Wuhan, China, Elizabeth Maruma Mrema, the acting executive secretary of the UN Convention on Biological Diversity, called for a global ban on wildlife markets to prevent future pandemics. Others called for already existing bans to be enforced, in order both to reduce cruelty to animals as well as to reduce health risks to humans.

Types of zoonotic disease transmissions

Direct contact transmissions occur when humans encounter first hand contaminated feces, urine, water sources, or bodily fluids. Bodily fluid transmission may happen either from ingesting pathogens or through open wound contact. Indirect contact transmissions occur when humans interact within an infected species' habitat. Humans are often exposed to contaminated soils, plants, and surfaces where bacterial germs are present. Contaminated food transmissions occur when humans eat infected bushmeat, vegetables, fruits, or drink contaminated water. Often these food and water supplies are tainted by fecal pellets of infected bats, birds, or monkeys. Vector-borne transmissions occur when individuals are bitten by infected parasites such as ticks or insects like mosquitos and fleas.

Other factors for escalated disease transmissions include climate change, globalization of trade, accelerated logging practices, irrigation increases, sexual activity between individuals, blood transfusions, and urbanization developments near infected ecosystems.

Health risks of zoonotic diseases

Exotic wildlife trafficking admits a number of infectious diseases that spell potential life-threatening results for human populations if contracted. Researchers believe eliminating the transmission of infectious diseases is not plausible. Instead, creating health screening services is critical for minimizing transmission rates among populations and infected wildlife species involved in trafficking.

Annually, 15.8% of human deaths have been associated with dangerous infectious disease outbreaks linked to exotic trafficking. Researchers, zoologists, and environmentalists determine that financially poor countries in Africa may attribute to nearly 44% of these deaths due to zoonosis related diseases.

Cultural determinants linking Africa to disease exposure

People in Africa are exposed to an increased risk of contracting and dispatching life-threatening zoonotic infections. The continent is considered a hot spot for emerging disease transmissions for reasons like socio-culture livelihood interests, livestock farming, land use methods, globalization influences, and consumption behavior practices.

Socio-Culture livelihood factors

Many Africans make a living from the wildlife trade due to the high market demand for exotic animals. These individuals partaking in poaching activities are able to produce an income by selling to vendors all around the world. However, hunters are highly susceptible to encountering infected droplets, water sources, soils, carcasses, and viral airborne pathogens while traveling through the bush. Once they have successfully hunted and killed the wild animal, they run the risk of blood or bodily fluid transfer from close contact with possible infected species. They're also at an increased risk of harvesting arthropod-borne pathogens carried in ticks. Often ticks can be found on the wild animal or in its surrounding wildlife habitat.

Livestock and land use methods

Potential increases in zoonotic disease transmissions have been associated with rising population numbers in both livestock and humans. Numerous African societies make their livelihoods from practicing pastoralism and traditional farming methods. In some cases infected wildlife sharing the same environment may come into contact with livestock and pass on these viral pathogens. Different zoonotic infections can intensify while residing in wild or domesticated animals and present deadly spillover into humans populations. Researchers believe future emergences of zoonotic diseases will be directly linked to agricultural and livestock farming methods.

A study conducted in Tanzania revealed major gaps in locals knowledge of zoonotic diseases. Individuals in these pastoral communities acknowledged health symptoms commonly found in both humans and animals, however they did not have a synthesized term for zoonosis and believed pathogens were not life-threatening. Researchers found that the pastoral communities were more concerned with keeping cultural practices of producing cooked meals rather than the potential infections harvested from the animals.

Globalization influence

A number of globalization threats have negatively impacted Africa's environmental habitats, biodiversity counts, and overall climate change. Developing urbanized landscapes requires deforestation. As a result, biodiversity counts decrease and growing human populations encroach further into the ecosystems of wildlife.

Urbanization impact on a region's biodiversity presents a serious issue. Landscapes inhabiting smaller biodiversity counts are more susceptible to rapid disease spread. Areas with a larger species diversity are more capable of reducing disease dispersal due to the number of possible hosts.

Logging patterns in Africa have grown exponentially over the years. Around 90% of the continent's individuals use wood as their primary energy source for preparing food and others use it for timber global trading purposes. With fewer trees, carbon dioxide and global greenhouse emissions are increasing and negatively affecting climate change.

Urbanizing new environments in Africa also increases the migration patterns of humans. New settlements and tourist attractions near these wildlife habitats bring vulnerable individuals with no disease immunity closer to areas of diseases.

Consumption behaviors

The greatest possibility of contracting deadly zoonotic diseases occurs during the bushmeat cooking process. Cooking exotic bushmeat requires sharp knives, steady handwork, and skilled techniques when correctly butchering an animal. Consumers often purchase bushmeat directly from African poachers. This means they have no way of knowing whether the wild animal is carrying dangerous zoonotic pathogens. On average people cut themselves 38% of the time when butchering bushmeat, allowing for infected bodily fluid transmissions. African women are more likely to contract these dangerous zoonotic pathogens because they are the ones handling and cooking the bushmeat.

Exotic trade and disease outbreaks

Ebola virus disease is a rare infectious disease that is likely transmitted to humans by wild animals. The natural reservoirs of Ebola virus are unknown, but possible reservoirs include fruit bats, non-human primates, rodents, shrews, carnivores, and ungulates.

Transmission of this virus likely occurs when individuals live closely to infected habitats, exchange bodily liquids, or consume infected animals. West Africa's Ebola outbreak was termed the most destructive infectious disease epidemic in recent history, killing a total of 16,000 individuals between 2014 and 2015. Wildlife poachers have the greatest chance of contracting and dispersing this disease at they return from the bush.

HIV is a life-threatening virus that attacks the immune system. The virus weakens the white blood cell count and their ability to detect and ward off potentially harmful diseases. Dispersal of the disease includes acts of consuming infected bushmeat, pathogens coming into contact with open wounds, and through infected blood transfers. The two major strains of HIV, HIV-1 and HIV-2, are both believed to have originated in West or Central Africa from strains of simian immunodeficiency virus (SIV), which infects various non-human primate species. Some of these primates affected by SIV are often hunted and trafficked for bushmeat, traditional medicine practices, and for exotic pet trade purposes.

Severe acute respiratory syndrome (SARS), often referred to as a severe form of pneumonia, is a highly contagious zoonotic respiratory illness causing extreme breathing difficulties. Factors attributing to widespread dispersal include the destruction of wildlife natural ecosystems, overextended urbanization effects on biodiversity, and contact with bacterially contaminated objects. The virus originated in tropical areas of Africa and Southeast Asia and is linked to their native bats and civets. Civet wildlife trade in Southeast Asian and African markets have been monitored to reduce the risk of future pathogen spread through spillover events.

Monkeypox is a viral zoonotic double stranded DNA disease that occurs in both humans and animals. It often accumulates in wild animals and is transmitted by close contact within animal trade. It is most commonly found in central and west Africa where it is carried in a number of infected species including monkeys, apes, rats, prairie dogs, and other small rodents. In an attempt to reduce the rate of disease spread, researchers believe minimizing direct and indirect contact rates between species in wildlife trade markets is the most practical solution.

Bubonic plague is caused by the bacterium Yersinia pestis and is transmitted through open wound contact or exposure to contaminated bodily fluids. Oriental rat fleas, which are thought to originate in northern Africa carry the bacteria and transmit the disease by biting and infecting both humans and wild animals. Small African rodents harbor this disease and infect prairies, wildlife markets, and other areas where large African primates and carnivores are hunted for bushmeat and exotic trade purposes. 

Marburg virus, which causes Marburg virus disease, is a zoonotic RNA virus within the filovirus family. It is closely related to the Ebola virus and is transmitted by wild animals to humans. African monkeys and fruit bats are believed to be the main carries of the infectious disease. In 2012 the most recent outbreak occurred in Uganda, where fifteen individuals contracted the disease and four ultimately died from elevated hemorrhagic fevers. Rising numbers of deforestation, urbanization, and exotic animal trade have increased the likeliness of spreading this viral disease.

West Nile virus is a single stranded RNA virus that can cause neurological diseases within humans. The first outbreak was recorded in Uganda and other areas of West Africa in 1937. Disease transmission is primarily through mosquitos feeding on infected dead birds. The infection then circulates within the mosquito and is transferred to humans or animals when bitten by the infected insect.

African trypanosomiasis or sleeping sickness is caused by a microscopic parasite called the Trypanosoma brucei, which is transferred to humans and animals through the bite of a tsetse fly. The disease is a reoccurring issue in many rural parts of Africa and over 500,000 individuals currently carry the disease. Livestock, game animals, and wild species of the bush are prone to the infection. Wildlife game markets and other exotic animal trade methods continue to spread transmission. These trade operations have introduced dangerous repercussions as the disease becomes more adaptive to drug resistance.

Budai

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Budai?fbclid=IwAR0oP64qxhuqs2lGRsMUTUWDNEMDsFKV7nmR49kJ0OF-ojVQDL6xHafjuqU#Conflation_with_other_religious_figures 

Statue of Budai at Vĩnh Tràng Temple

 

Budai
Chinese name
Chinese	布袋

Alternative Chinese name
Chinese	笑佛
Literal meaning	Laughing Buddha

Transcriptions
Second alternative Chinese name
Chinese	胖佛
Literal meaning	Fat Buddha

Transcriptions
Vietnamese name
Vietnamese alphabet	Bố Đại
Hán-Nôm	布袋
Thai name
Thai	พระสังกัจจายน์จีน
RTGS	Phrasangkajaijeen
Korean name
Hangul	포대
Hanja	布袋

Transcriptions
Japanese name
Kanji	布袋
Hiragana	ほてい

Budai (Chinese: 布袋; pinyin: Bùdài; Japanese: 布袋, romanized: Hotei) is a semi-historical Chinese monk who is venerated as Maitreya Buddha in Chan Buddhism. He was also introduced into the Japanese Buddhist pantheon. He allegedly lived around the 10th century in the Wuyue kingdom. His name literally means "cloth sack", and refers to the bag that he is conventionally depicted as carrying as he wanders aimlessly. His jolly nature, humorous personality, and eccentric lifestyle distinguish him from most Buddhist masters or figures. He is almost always shown smiling or laughing, hence his nickname in Chinese, the "Laughing Buddha". As he is traditionally depicted as fat, he is also referred to as the "Fat Buddha", especially in the Western world.

The main textual evidence pointing to Budai resides in a collection of Zen Buddhist monks' biographies known as The Transmission of the Lamp.

Hagiography

Budai has origins centered around cult worship and local legend. He is traditionally depicted as a fat, bald monk wearing a simple robe. He carries his few possessions in a cloth sack, being poor but content. He would excitingly entertain the adoring children that followed him and was known for patting his large belly happily. His figure appears throughout Chinese culture as a representation of both contentment and abundance. Budai attracted the townspeople around him as he was able to predict people’s fortunes and even weather patterns. The wandering monk was often inclined to sleep anywhere he came to, even outside, for his mystical powers could ward off the bitter colds of snow and his body was left unaffected. A recovered death note dated to 916 A.D., which the monk himself wrote, claims that he is an incarnation of the Maitreya, the Buddha of the Future.

Chan/Zen Buddhism

Budai was one of several "uncommitted saints" that became incorporated into the Chan pantheon. Similar "eccentric" figures from the lamp histories were never officially inducted or appropriated into the Chan patriarchal line. Instead, these obscure figures represented the "special transmission" that occurred during the early to mid 12th century. This transmission did not rely on patriarchal lineage legitimacy, but instead used the peculiar personalities and qualities of various folkloric figures to illustrate the Chan tradition's new commitment to the idea of "awakening" and the propagation of Chan to a larger congregation. The Chan Masters, Dahui Zonggao (1089–1163) and Hongzhi Zhengjue (1091–1157), were both leaders in the initial merging of local legend and Buddhist tradition. They hoped the induction of likeable and odd figures would attract all types of people to the Chan tradition, no matter their gender, social background, or complete understanding of the dharma and patriarchal lineage. Bernard Faure summarizes this merging of local legend and Chan tradition by explaining, "One strategy in Chan for domesticating the occult was to transform thaumaturges into tricksters by playing down their occult powers and stressing their thus world aspect..." The movement allocated the figures as religious props and channeled their extraordinary charismas into the lens of the Chan pantheon in order to appeal to a larger population. Ultimately, Budai was revered from both a folkloric standpoint as a strange, wandering vagabond of the people as well as from his newfound personage within the context of the Chan tradition as a 'mendicant priest' who brought abundance, fortune, and joy to all he encountered with the help of his mystical "cloth sack" bag.

In Art

As Zen Buddhism was transmitted to Japan around the 13th century, the devout monastics and laymen of the area utilized figure painting to portray the characters central to this "awakening" period of Zen art.^[6] Many of the eccentric personalities that were inducted into the Zen tradition like Budai were previously wrapped up in the established culture and folklore of the Japanese people. The assimilation and reapplication of these wondrous charismas to the Zen pantheon assisted in the expansion of the Zen tradition. Budai is almost always depicted with his cloth sack that looks like a large bag. The bag serves as a prominent motif within the context of Zen Buddhism as it represents abundance, prosperity, and contentment. Ink paintings such as these attributed to Budai often had an inscription and seal that signaled to high ranking officials. For example, Budai and Jiang Mohe was inscribed by Chusi Fanqi, who was closely related to Song Lian (1310–1381) and Wei Su (1295–1372).

As the images demonstrate, Budai is most jubilant when in the presence of others, especially children. When depicted with other gods in the Seven Lucky Gods, Budai maintains a solemn or even depressed countenance. Budai's round figure comes into practical use through the sculpting of the incense box (18th century) that splits the monk's body into two halves. The newer images such as Hotei and Children Carrying Lanterns (19th century) employs much more color, dramatization of physical features, and detail than the older pieces such as Hotei from Mokuan Reien (1336) that employs much more wispy and heavily contrasting outlines of his figure with no color or assumed setting.

Sculpture

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  Glazed ceramic sculpture of Budai. Ming Dynasty, 1486.
  
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  Jade figurine of Budai. 17th–18th century.
  
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  Incense box in the form of seated Hotei. 18th–19th century.
  

Paintings

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  Budai and Jiang Mohe Discussing Buddhism, by Yintuoluo and inscribed by Chushi Fanqi. Circa 1350.
  
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  Hanging scroll showing Hotei, by Mokuan Reien and inscribed by Liao'an Qingyu. 14th century.
  
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  Painting of Hotei, by Kanō Kōi of the Kanō school. Early 17th century.
  
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  Hotei Pointing to the Moon, by Fūgai Ekun. 17th century.
  
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  Hotei and Children Carrying Lanterns, by Utagawa Kuniyoshi. 19th century.
  

Conflation with other religious figures

Gautama Buddha

In the Western World, Budai is often mistaken for Gautama Buddha himself, and thus is nicknamed the "Fat Buddha".

Angida

Budai under a pine tree, by Wang Zhen. 1921

Angida was one of the original Eighteen Arhats. According to legend, Angida was a talented Indian snake catcher whose aim was to catch venomous snakes to prevent them from biting passers-by. Angida would also remove the snake's venomous fangs and release them. Due to his kindness, he was able to attain bodhi.

In Chinese art, Angida is sometimes portrayed as Budai, being rotund, laughing, and carrying a bag.

Phra Sangkajai

In Thailand, Budai is sometimes confused with the arhat Kaccāna, known in Thailand as Phra Sangkajai or Phra Sangkachai. Buddha praised Phra Sangkajai for his excellence in explaining sophisticated concepts of the dhamma in an easily and correctly understandable manner. Phra Sangkajai is also known for composing the Madhupindika Sutta.

One story from Thai folklore relates that Phra Sangkajai was so handsome that even a man once wanted him for a wife. To avoid a similar situation, Phra Sangkajai decided to transform himself into a fat monk. Another tale says he was so attractive that angels and men often compared him with the Buddha. He considered this inappropriate, so disguised himself in an unpleasantly fat body.

Although both Budai and Phra Sangkajai may be found in both Thai and Chinese temples, Phra Sangkajai is found more often in Thai temples, and Budai in Chinese temples. Two points to distinguish them from one another are:

1. Phra Sangkajai has a trace of hair on his head (looking similar to the Buddha's) while Budai is clearly bald.
2. Phra Sangkajai wears the robes in Theravada fashion, with the robes folded across one shoulder, leaving the other uncovered. Budai wears the robes in Chinese style, covering both arms but leaving the front part of the upper body uncovered.