Module 3 exam: Manual handling of the deceased and infection control
Before we start ……
Before attempting the online quiz below please read all sections of this page and take notes as you go to produce revision guides to help with the exam questions below.
Quiz exam questions can be based on any material presented to you during the course including presentations, assignments and any guided reading contained on this page relating to LO2 for this module (Working with infection control).
Don’t feel bad if you need to ask for help. People you can talk to about exams include mentors, course facilitators, candidates and other work placed staff.
Let’s begin ……
This part of the web page will require you to read the online notes below providing you with an introduction to Microbiology (the study of microorganisms) and infection control, and how these topics are relevant to your areas of work so that you can work in a safe way to help reduce the risk of infection.
What is microbiology?
Microbiology is the study of all living organisms that are too small to be visible with the naked eye. This includes bacteria, viruses, fungi and protozoa, collectively known as 'microbes'.
Although microbes are impossible to see with the naked eye, they make up 60% of all living matter on Earth with a massive impact in each and every other living organism on the planet. Microbes play key roles in nutrient cycling, decomposition, climate change, food spoilage, as well as the cause and control of disease.
Good or bad bacteria?
Comparatively speaking, there are only a handful of “bad” bacteria out there. Of the total bacteria in our bodies, a healthy balance is 85% good bacteria and 15% bad bacteria. Remarkably, scientists estimate that only 1-10% of total bacteria have even been discovered.
Bacteria can survive in the harshest conditions and they are everywhere; throughout our environment, on our skin, in our mouth and in our gut.
Around 100 trillion good bacteria live in and on our bodies. Many of these bacteria reside in our gut, helping our body break down food and absorb nutrients. Not only do we live in harmony with these good bacteria, but they are essential to our survival.
Bacteria in our gut help to protect us by crowding out some of their dangerous relatives that can cause disease. Other good bacteria have been used in medicine to create antibiotics, and others still are used in food production to make fermented foods such as yogurt - however even ‘good’ bacteria in the wrong environment can cause disease.
What is Infection Prevention and Control?
Infection control is the discipline concerned with preventing 'healthcare associated infection'.
In the workplace it is easier to manage the general hazards associated with any work environment as we can identify the level of risk caused by slip, trips, falls, manual handing or exposure to hazardous substances. However, with infection control this is far more difficult as you literally cannot see the level of risks associated with Micro-organisms.
Standard Infection Control Precautions (SICPs) such as hand hygiene and use of Personal Protective Equipment (PPE) are the basic infection prevention and control measures necessary to reduce the risk of infecetion and transmission of infectious agents (micro-organism) from both known and unknown sources of infection.
Sources of (potential) infection include blood and other body fluids secretions or excretions (excluding sweat), non-intact skin or mucous membranes and any equipment or items in the care environment that could have become contaminated.
Types of micro-organisms ……
1 Bacteria
Bacteria are ubiquitous in nature, meaning they can be found everywhere in the environment, such as air, soil and water, and are members of a large group of unicellular (consisting of a single cell) microorganisms. Although bacteria have cell walls they lack organelles (organised or specialised internal structures e.g. nucleus) like most of our cells do. They are believed to be some of the first life-forms that emerged on earth. As previously stated some bacteria are good for you, including the bacteria in your digestive system, others harmful that release toxins that can damage your body’s tissues and make you feel ill.
There are four main phases in the life cycle of bacteria:
A. The Lag Phase: In this phase, bacteria do not grow. They are getting use to their environment and try to adjust and stay alive. During this phase, they produce amino acids and vitamins which are required for division. Duration of this phase depends on the availability of nutrients. If enough nutrients are available, the duration will be short and if not then this phase will take time.
B. The Log Phase: In this Phase, bacteria multiply very rapidly. If provided favourable conditions then they can get doubled in approximately 15 minutes but if conditions are not suitable then this stage can take time. The time taken by bacteria to get doubled is known as ‘Exponential Phase’. The process through which bacteria multiply is known as binary fission.
Binary fission ("division in half") is a kind of asexual reproduction – the bacteria duplicates its genetic material and then divides into two.
C. The Stationary Phase: This phase is also known as the phase of decline in bacteria growth. This decline depends on the amount growth nutrients and waste products. Growth and death rates are equal in the stationary phase.
D. The Death Phase: As the name implies, it is the last stage. In this phase, bacteria lose the ability to reproduce.
2 Fungi
Fungi is the plural word for "fungus". A fungus is a eukaryotic organism (cells that have a nucleus). Yeasts, moulds and mushrooms are examples of fungi. Most fungi are large enough to be seen with the eye. However, some are microscopic organisms and the study of microscopic fungi is called mycology. Some microscopic fungi, for example yeast, are used in the food and drink industry to produce bread, beer and wine. Some microscopic fungi species are pathogenic (cause disease) to animals (including man) and plants - most people are aware of some of the superficial infections caused by fungi such as athlete's foot.
Many fungi reproduce my releasing spores that germinate in a subsurface medium (i.e. away from the light such as soil) that grow into hypha (root like structures). The hypha’s produce external fruiting bodies in the air to release more spores.
3 Viruses
Viruses are generally much smaller than bacteria and lack the capacity to thrive and reproduce outside of a host body. Viruses teeter on the boundaries of what is considered life. On one hand, they contain the key elements that make up all living organisms: e.g. DNA or RNA, (any given virus can only have one or the other). On the other hand, viruses lack the capacity to independently read and act upon the information contained within their DNA or RNA so cannot reproduce outside of a host. Because viruses are so simple in structure they lack any of the complicated machinery that most of our cells have and need to access the inside of a host’s body. Respiratory passages and open wounds can act as gateways for viruses.
Viral replication needs a living host (e.g. a cell):
The life cycle of a virus involves: (1) attachment to the surface of a cell, then (2) penetration of the cell membrane and the viral generic material being released (3) from inside the virus which is then incorporated into the host cell genetic material. The virus highjacks (4) the host cell to produce more copies of its genetic material (e.g. biosynthesis) and then these parts are (5) assembled into new viruses. Eventually the large numbers of viruses erupt from the cell (6) to infect more cells (usually killing the cell in the process.
4 Protozoa
Most Protozoa are free living single celled organisms with complex internal structures. Historically, the protozoa were regarded as "one-celled animals", because they often possess animal-like behaviours, such as motility and predation.
They come in many different shapes and sizes, some fixed and others such as Amoeba can change its shape. They live in a wide variety of moist habitats including fresh water, marine environments and the soil.
Some Protozoa have evolved and stopped their free living to become parasitic, which means they live in other plants and animals including humans, where they cause disease.
Some Protozoa reproduce by the method of binary fission (like bacteria), others reproduce by sexual means, and some by both methods.
Based on the mode of locomotion, protozoa have been divided into four types.
Protozoa types
1. Amoeboids are capable of changing its shape, mainly by extending and retracting pseudopods.
2. The Ciliates are a group of protozoa which possesses hair-like organelles called cilia that can move in waves and are used in swimming, crawling, and feeding.
3. Sporozoa are non-motile and are usually intracellular parasites (i.e. live inside other cells).
4. Flagellates are protozoa which have one or more whip-like organelles called flagella that are used to move.
Protozoa can cause disease in humans:
1. Plasmodium, for example, are a type of protozoa that cause malaria. They belong the Sporozoa group, and this parasite is mainly spread by female Anopheles mosquitoes, which mainly bite at dusk and at night. When an infected mosquito bites a person, it passes the malaria protozoa parasites into the bloodstream.
2. Another protozoa type called Entamoeba has evolved to live solely in animals with some species becoming invasive causing the disease amoebic dysentery. They belong to the amoeboid group. Entamoeba is transmitted primarily through the faecal-oral route by contaminated food and water supplies.
3. The world's most common cause of water-borne diarrhoea is caused by the flagellate Giardia with outbreaks common in schools, mental hospitals, prisons, and other crowded institutions. Giardia is also transmitted through the faecal-oral route with the parasite being picked up from surfaces (such as bathroom handles, changing tables, toys) that contain faeces from an infected person or animal.
Mortuary specific microbiology and infection risks ……
Micro-organisms and death
Decomposition begins several minutes after death, with a process called autolysis, or self-digestion. Enzymes released during this process start to digest cell membranes that then leak their contents as they break down - this results in more enzymes being released causing a rapid cascade of tissue breakdown. This usually begins in the liver, which is enriched in enzymes, and in the brain, which has high water content; eventually, though, all other tissues and organs begin to break down in this way.
Damaged blood cells spill out of broken vessels and, aided by gravity, settle in the capillaries and small veins, discolouring the skin. Refrigeration can slow down the process of decomposition.
Most internal organs are devoid of microbes when we are alive. Soon after death (in conjunction with autolyses), the immune system stops working, allowing them to spread throughout the body freely. This usually begins in the gut, at the junction between the small and large intestines. Left unchecked, our gut bacteria begin to digest the intestines, and then the surrounding tissues, from the inside out, using the chemical cocktail that leaks out of damaged cells as a food source. Then they invade the capillaries of the digestive system and lymph nodes, spreading first to the liver and spleen, then into the heart and brain.
So shortly after death organisms that are usually found in one place (or environment) within the body can become more systematic throughout the deceased body increasing the risk of infection to mortuary staff.
Risk of infection from the deceased
If normal protocols and procedures are followed within your organisation the risk the deceased pose for the public is extremely small. However, persons who are involved in close contact with the deceased, such as workers in the mortuary, may be exposed to chronic infectious hazards, including hepatitis B virus, hepatitis C virus, HIV, Clostridium difficile, enteric pathogens (bacteria found in the gut), and Mycobacterium tuberculosis (TB).
Suitable precautions for mortuary staff (and funeral service staff) include training, use of body bags and disposable gloves, good hygiene practice, and vaccination for hepatitis B and tuberculosis. Disposal of bodies should respect local custom and practice where possible. These practices will ensure the actual infection risks to mortuary staff are small.
Risk assessment
As you have learnt in module 2 risk assessment is about identifying, and taking sensible and proportionate measures to control the risks in your workplace; it is not about creating huge amounts of paperwork.
You are probably already taking universal steps to protect yourself and others from the risk of infection such as washing hands, having designated clean areas and use of PPE for example.
When considering how to control the risks of infection, it may be useful to compare infection to the links in a chain (see image below). Breaking a link in the chain at any point will often control the risk of infection.
Infection Prevention and Control strategies are aimed at breaking the chain at one of its links
Good mortuary practice to reduce the risk of infection ……
Standard infection control precautions
Standard infection control precautions (SICPs) were developed to manage the risks of infection from patients in healthcare settings, but they are also applicable as a means of controlling the risks of infection from the deceased.
SICPs are the basic infection prevention and control measures that should be used at all times, whether infection is known to be present or not, to ensure the safety of workers and visitors.
SICPs are a combination of organisational arrangements, safe working practices, use of PPE, and the application of appropriate behaviours. Their application should take account of the task being performed, the level of interaction and/or the anticipated level of exposure to blood and/or other body fluids. SICPs can be categorised into nine areas which are applicable to work with the deceased:
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Safe management of the environment
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Location for handling the deceased and assessment for infection risk
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PPE
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Hand washing
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Safe management of equipment
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Safe management of blood and body fluid spillages
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Occupational safety: prevention and exposure management (including sharps)
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Safe management of linen (including uniforms or work clothing)
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Safe disposal of waste (including sharps)
Transmission-based precautions
Where SICPs are not considered sufficient to manage the risks of infection, usually because the deceased is known or suspected to be infected, additional precautions will be necessary. These are known as transmission-based precautions (TBPs) as the control measures required are selected on the basis of the route of transmission of the infectious microorganism. This can be via one of the following routes:
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Airborne (e.g. local exhaust ventilation, down-draught tables, respiratory protective equipment)
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Droplet (avoid activities likely to cause splashing, such as washing down with high-pressure hoses)
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Physical Contact (e.g. use of leak-proof body bag, double gloving, single-use instruments)
Poor mortuary practices can increase the risk of infection, infestation and disease, example of poor practice include:
• Not following proper hand washing protocols
• Lack of / incorrect use of PPE
• Incorrect cleaning regimes / disinfectants used
• Unsuitable storage
• Appropriate body bags / containers not being used
• Lack of warnings, hazards, signs / notifications
• Infrequent linen and clothes changes
• Poor waste disposal protocols
• Poor / infrequent maintenance procedures / checks
• Poor immunisation compliance
• Inadequate reporting of issues or problems (or follow up investigations)
• Not following SOP’s
• Unnecessary aerosol formation (e.g. use of high pressure hoses, inadequate ventilation)
• Poor technical practises and PM techniques
• Lack of training
• Clean / dirty areas not clearly identified
• Poor communication
Quiz time ……
Remember as well as the revision notes you have taken from reading the notes above you will also need to read through your microbiology presentation as questions can be taken from these as well.
Instructions
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Click the start button and then answer questions from the multiple-choice selection - there are 15 questions in total.
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A green tick indicates a correct answer, a red cross an incorrect answer (the correct answer will be displayed if you get it wrong).
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After a short period of time further information relating to the correct answer will be displayed.
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Click the arrow in a circle icon for the next question.
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Some questions contain images - click the eye icon to see the entire image.
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Attempt the quiz as many times as you like, but you will only be allowed to enter your name when you have passed the quiz. Once passed your results will be sent to the North tees Centre.