Microbiology Final (Sessions 2 - 8, Diseases and Biosafety) Flashcards
What causes anthrax?
Bacteria (bacillus anthracis)
What is the treatment for anthrax?
antibiotics
How is anthrax transmitted?
Spores get into the body (breathed in, ingested, through scrape or cut, injection).
How do you diagnose anthrax?
Measuring antibodies or toxin in blood. Testing for B.anthracis in body fluid or tissues.
How can you prevent anthrax?
Vaccine only given to high risk people. Antibiotics in exposed people.
Anthrax threat to health care providers.
Unlikely to be a high risk of infection.
What do you call a pathogen that can cause disease in both humans and animals and is transferable between them?
Zoonotic pathogen
The main difference between risk group 3 and 4 is that the risk to public health is low is risk group 3, and high in risk group 4, despite the fact that the pathogens in each group are very likely to cause serious disease. What is the key fact that determines this difference?
Effective treatment and preventative measures are usually available in risk group 3 and not usually available in risk group 4.
Why can some certain risk group 1,2,3 pathogens be housed within a certain containment level that does not correspond to their risk group level?
Depending on the pathogens characteristics, and the work being done with the pathogen (planned activities), the level of containment can vary among the different risk groups.
Describe a risk group level 3.
The level 3 risk group is considered to be any pathogens or toxins that are high risk to individuals and animals with a low risk to the community.
Who are the only individuals likely to be affected by a risk group 1 (RG1) pathogen?
Immunocompromised individuals.
Ebola is a highly infectious, and lethal pathogen that can cause serious economical and health implications on a society, which level of contamination would it most likely be handled in?
Since Ebola is a highly lethal pathogen, it must be handled in containment level four, due to that level having specific engineered controls that help prevent the spread of any pathogens from the laboratory.
Name the 4 risk groups and briefly explain what each group means and provide an example of each.
Risk group 1: A pathogen that has been determined a low health risk for individuals and the public. Example: Lactobacillus acidophilus-
Risk group 2: A pathogen presenting a moderate health risk to individuals but low risk for the public. Example: Listeria monocytogenes
Risk group 3: A pathogen presenting a high risk to individuals but low risk to the public. Example: SARS
Risk group 4: A pathogen presenting a high risk for both the public and individuals. Example: Ebola Virus
Why should we document right after an incident occurs?
To promote the accuracy of the information documented with complete detail and diminish the effect of a recall bias. It is also useful because then the information gathered can allow for valid comparison with other incidents.
What is an example for the route of exposure Inoculation?
Getting poked by a dirty needle
Give three reasons why LAI’s are underreported.
a. Many LAI’s are asymptomatic (the individual doesn’t even realize they have an infection
b. Many workers feel there is a possibility of punishment
c. Many countries don’t have a legal requirement or mechanism to report
What is the difference between an accident and an incident?
An accident is an event that results in injury or damage whereas an incident is an event that has the potential to cause injury or damage.
Why are laboratory acquired infections dangerous?
Because an infected worker may pose a risk for secondary transmission to the general public.
Why is it important to report any incidence of exposure or contact with a microbe?
Some microbes may be symptomatic or asymptomatic so its important to be extra cautious to protect the general public and also receive medical attention for any exposures.
What is an exposure? What are the different routes of exposure?
Exposure is coming in contact with or very close to an infectious biological material. The different routes of exposure are: i. Inhalation (via aerosols) ii. Inoculation (needle sticks or bites) iii. Ingestion (through the mouth or contamination of food and drink) iv. Absorption (through splashes or spills on skin and mucous membranes).
What kind of source of infection is a concern for blood borne viruses?
Needle, syringe
What is the greatest biohazard facing laboratory workers?
Airborne particles
The inconsistent use of _______ and the questionable integrity of them has been anecdotally associated with LAI’s.
Gloves
Whose responsibility is it to make sure that decontamination occurs properly, and should you trust other to have followed decontamination protocol accurately?
Everyone who comes in contact with pathogens should take responsibility to promote health and safety by decontaminating materials. It should not be assumed that tools and surfaces have been decontaminated properly by others. If you are unsure and feel their may be a hazard, it is your responsibility to keep yourself and others safe by decontaminating them again before use.
What is one microorganism that can be killed using a low-level disinfectant such as sanitizer?
A fungi, vegetative bacteria, or enveloped virus
What is the causal agent of diptheria?
bacterium, corynebacterium duotheriae
How is diptheria transmitted?
Via respiratory tract through droplets. Less commonly through direct contact with contaminated fomite or milk.
How is diptheria diagnosed?
Signs and symptoms plus lab culture results (throat or lesion swab)
What is the treatment for diptheria?
antibiotics
How can diptheria be prevented?
vaccine
What are precautions for health care workers for diptheria?
Droplet precaution, gloves and hand hygiene
Define microbe.
Very small, living or non-living organisms (or infectious elements) that usually cannot be seen with naked eyes. They can be cellular or acellular, they can be autotroph or heterotroph, motile or sessile.
Who was the first to see and describe a microbe and use a microscope?
Robert Hooke
Who was the first person to observe and describe a bacteria?
Antoni van Leewenhoek
Who disproved the theory of spontaneous generation?
Pasteur
Who proved the link between causal agents and infectious diseases?
Robert Koch
Who discovered penicillin?
Alexander Flemming
Who first used phenol to sterilize surgery tools and wounds and conducted the first aseptic surgery?
Joseph Lister
What is the causal agent of COVID-19?
Severe Acute Respiratory Syndrome-Related Coronavirus-2 (SARS-CoV-2). SARS-CoV-2 is a Single-stranded, positive-sense RNA, enveloped Virus
How is COVID-19 transmitted?
COVID-19 is transmitted through respiratory droplets and becomes an airborne particle. COVID-19 virion can live on surfaces and can be transmitted by contacting the surfaces then touching the face.
What is the incubation period for COVID-19?
The incubation period for COVID-19 is currently one, to fourteen days with eleven days being the average timeframe, during this time the host can infect another person for up to three days prior to any symptoms developing.
How is COVID-19 diagnosed?
Nucleic acid amplification (PCR)
How is COVID-19 treated?
Currently there is no global cure, or global vaccine to treat COVID-19
How do you prevent COVID-19?
- Due to its high transmission rates there should be limited close proximal contact with infected hosts
- Physical distance with a host should be maintained at a minimum of 6 ft, due to the possibility of transmission with asymptomatic, pre-symptomatic, and symptomatic hosts it is difficult to know who a carrier is and who is not
- When a high population of people ware masks the rate of transmission decreases significantly
Risk of COVID-19 to health care professionals.
Healthcare Professionals are at risk of developing severe symptoms due to exposure to higher viral load of COVID-19, and from fatigue of working long hours
What causes ebola?
Ebola virus
How is ebola transmitted?
Bats are reservoir hosts for the virus. Infected bats transmit the virus to nonhuman primates, which then infects humans through direct contact. Human to human transmission occurs via direct contact (through broken skin/mucous membranes) with blood, tissue or other body fluids of infected individuals and through sexual transmission. It can also occur via indirect contact (through contaminated medical equipment or environmental surfaces).
How is ebola diagnosed?
Ebola is diagnosed based on symptoms, travel history and laboratory testing.
Laboratory tests to diagnose Ebola include: Immunofluorescence techniques and Polymerase chain reaction (PCR).
How do you treat ebola?
There is currently no cure for Ebola. Patients are only treated to help with the symptoms which includes: supporting blood pressure and oxygen delivery, ensuring that the patient’s fluid and electrolytes level are within normal range and strict isolation in an intensive care unit (this is for the prevention in the spreading of the disease).
How can you prevent ebola?
First prevention is to avoid direct contact with bodily fluids of people with Ebola (e.g. urine, blood, saliva, vomit, semen and breast milk).
Second, is to avoid direct contact with bodies of people who have died of Ebola or any unknown diseases and to avoid direct contact with medical equipment such as needles that were contaminated with blood or bodily fluids; and lastly is to avoid contact with live and dead animals such as Monkeys, Fruit bats.
What impacts are there of ebola to health care professionals?
Strict infection control measures should be practiced. Isolate infected individuals, use personal equipment like gowns, masks, gloves and goggles properly (to block splashes or other contact with infected materials), disinfect or dispose instruments and equipment properly, perform basic hand and respiratory hygiene, and perform safe injection and burial practices.
“CDC recommends that all healthcare workers entering the room of a patient with Ebola wear respiratory protection that would protect them during an aerosol-generating procedure. This would include a NIOSH-certified, fit-tested N-95 or higher respirator, or a PAPR.”*.
What is often done before sterilization or disinfection to reduce the number of micro-organisms on an object?
Objects are often cleaned first to remove soil or organic material, especially heavily soiled objects.
What microorganisms are the most susceptible to disinfection?
Vegetative bacteria, particularly gram-positive bacteria, fungi, and enveloped viruses
True or False. Enveloped viruses are harder to kill than naked viruses with low-level disinfectants?
False
Put the following in order of least resistant to most resistant: bacterial endospores, fungal spores, prions, enveloped viruses, non-enveloped viruses.
Enveloped virus, Fungal spore, Non-enveloped virus, Bacterial endospore, Prion
What is the single most important method to prevent the spread of infection?
Proper handwashing technique
Which prion disease can affect both livestock and humans alike, but goes by different names based on its host?i)
Bovine Spongiform Encephalitis or Creutzfeldt-Jakob Disease.
Pathogen Safety Data Sheets (PSDS) are sheets that identify the risks of pathogens and explain how to properly handle potentially harmful pathogens in a laboratory environment, what is one downside to the Pathogen Safety Data Sheet?
Although PSDS contain crucial information regarding certain pathogens, the pathogen safety data sheet does not contain information about every pathogen, therefore, it isn’t guaranteed to help students deal with pathogens.
Killing, inhibiting, or removing micro-organisms that may cause disease. Usually carried out through thermal, chemical, or radiological-processes.
a. Sterilization
b. Decontamination
c. Cleaning
d. Disinfectant
Disinfectant
What are 2 disadvantages of incineration?
Living organisms may be released because of changes in the waste content and the equipment hazardous pollutants could be put into the environment.
What are the four methods of decontamination?
Sterilization-Disinfection-Decontamination-Cleaning
Plasma torches are used in decontamination and can reach a temperature range of
between 3000 degrees Celsius and 8000 degrees Celsius
Name the most appropriate form of decontamination and disposal that a cancer center would need for the drugs they use to treat and kill cancerous cells in their patients.
Incineration
What are two types of steam decontamination methods?
Autoclaves and biowaste cookers
While incineration is an effective decontamination method, it also has many disadvantages. One of these disadvantages are that the incineration is bad for the environment. Why is this the case?
During the burning of the waste, microorganisms and many chemical pollutants may be released into the environment. It is for this reason that incineration often times does not even meet emission regulations.
Although there are many methods of decontamination, what is the preferred method of decontamination in laboratory settings?
Autoclaving is the preferred method for decontamination for laboratory settings, because it uses a sealed and controlled chamber to sterilize materials.
How are cytotoxic drugs handled in facilities?
They are handled in a similar way to biomedical waste but with one vital difference, they must be isolated from other biomedical waste. It is also important to not refrigerate or autoclave cytotoxic drugs they must be incinerated.
What kind of training must the employer provide before an employee can handle hazardous matter?
Training must be given on the recognition, packaging, transport, and the proper way to handle and store hazardous matter.
What type of biomedical waste poses the greatest risk for exposure to pathogens?
Sharps-related accidents pose the greatest risk for workers handling biomedical waste when they are not separated from other waste properly or caused by containers breaking.
True or False? Gloves have been used in the lab and now have to be thrown out. It has come in contact with an infectious material. It should still be placed in the regular garbage.
False, it is a biomedical waste because of the infectious contact.
A laboratory worker is disposing of cytotoxic waste, what are some special considerations?
Cytotoxic waste should be separated from other wastes, it should be labelled as “cytotoxic waste,” and it should not be refrigerated but it should be incinerated
What are four reasons why it’s important that establishments have a proper waste management program?
The four reasons are that if there is not a waste management there can be poor risk management, occupation safety risks, contamination to the environment and a possible breach to the containment of contagious diseases.
What type of biomedical waste container is ridged, leak proof, sealable and puncture resistance?
a. Sharps container
b. Reusable waste container
c. Cardboard container
d. Plastic waste holding bag
a. sharps container
Biomedical waste management is extremely important, waste is separated into two sections, hazardous and non-hazardous, however, cytotoxic waste must be segregated from both of those sections, why?
Cytotoxic waste which is used in cancer treatments has the ability to kill living cells and tissues, therefore, it is extremely important that it be isolated from all other types of waste because it could be accidentally released and cause biological problems for individuals in contact with the material.
What are the 3 major criteria for classifying viruses?
The type of nucleic acid (DNA or RNA); 2) the presence or absence of an envelope; 3) the manner of replication
Briefly list Koch’s postulates.
- The suspected pathogen must be present in all cases of the disease and absent from healthy animals.
- The suspected pathogen must be grown in pure culture.
- Cells from a pure culture of the suspected pathogen must cause disease in a healthy animal.
- The suspected pathogen must be reisolated and shown to be the same as the original.
Who disproved the theory of spontaneous generation?
Pasteur