180 infection Flashcards
1
Q
A microorganism is: 3 things
A
• an organism too small to be seen without the aid of a microscope
Size smaller than 0.1 mm or 100 um
• relatively simple in structure and often unicellular (single celled); also called a “microbe
2
Q
The four groups of microorganisms are:
A
(Protozoa, Fungi, Bacteria, Viruses)
3
Q
protozoa, 2 key features
A
-Protozoa are unicellular creatures that are able to move either by flagella or amoeboid (pseudopods) motion
-Each cell has a nucleus and is enclosed by a plasma membrane.
-Protozoa live in water and soil and feed on bacteria and small particles.
-Some protozoa live in our bodies without causing any harm but a few are responsible for disease
4
Q
2 types of protozoa
A
(Parasites, Amoebae)
5
Q
parasites 2 examples and they move by what
A
Giardia lamblia, Trichomonas
flagella
6
Q
Giardia lamblia
A
• Most common protozoa in Canada
• Found in lakes, streams and rivers
• Locomote by flagella and attach to intestinal wall by two sucking discs
• Infection results in giardiasis or “beaver fever”
7
Q
Trichomonas vaginalis
A
Sexually transmitted parasite
• Found clinically in urine and vaginal swabs
• Locomote by flagella
8
Q
• Amoebae example and movement
A
Entamoeba histolytica
9
Q
Entamoeba histolytica
A
• Predominantly infects humans causing amoebiasis
• Only 10-20% of people will exhibit symptoms; symptoms can include bloody diarrhea and abdominal pain
• Found in water and contaminated foods
• Prevention through improved sanitation
10
Q
Fungi, 3 key
A
• Can be single celled or complex multicellular organisms
• Nucleus and rigid cell wall
• Divided into yeasts and moulds
11
Q
yeast: 3, type or repro
A
• unicellular
• asexual budding reproduction
• Infections include: oral thrush or vaginal yeast infections caused by Candida sp.
12
Q
moulds key 3
A
• multicellular structures
• Asexual hyphae reproduction
• Infections include: Athlete’s foot and ringworm
13
Q
bacteria 4 key, where often found /?
A
• Unicellular; rigid cell wall
• No organized nucleus
• Found everywhere there is moisture and nutrients
• Can cause infections
14
Q
virus 2 key
A
• Requires a host for survival (obligate intracellular parasites)
• Contain only one type of nucleic acid (DNA or RNA)
• Very tiny
• Rely on host for ability to reproduce
• Viruses cannot multiply in the non-cellular environment and do not grow in foods, water, bacterial culture media, or medications.
15
Q
virus composed of 3
A
of nucleic acid, protein coat and sometimes lipids/ envelope
16
Q
envelope - virulence
A
• Lipid envelope ↓ virulence (easier to kill) with disinfectants
17
Q
treatment for the 4 micor
A
• Protozoal infection = antiprotozoal drug
• Fungal infection = antifungal drug
• Bacterial infection = antibiotic
• Viral infection = antiviral
18
Q
size of micor
A
protozoa 15-10
fungi 5-10 um
bacteria 0.3-5
virus 0.02-0.2
19
Q
shape of bacteria is maintained by
A
rigid cell wall
20
Q
3 shapes of bacteria
A
Cocci = round/spherical shaped
Bacilli (Rods) = rectangular shaped boxes
Spirilla = curved or spiral shaped
21
Q
gram stain
A
• Developed in 1884 by Hans Christian Gram
• Allows bacteria to be easily viewed under a microscope
• Bacteria can be divided into two groups based on their ability to take dye in during staining process
• Gram Positive = Purple (or bluish-black)
• Gram Negative = Pink/ Red
22
Q
3 reasons for gram stain
A
• First step in bacterial identification
• Aids doctor’s decision on course of antibiotics and appropriate disinfectant to use
23
Q
Bacterial Endospores happen in which bacteria
A
gram positive rods
24
Q
spores can 3 key
A
• Occur in a few types of gram positive rods
• Spores can live for months or years without nutrients or moisture
• Spores are resistant to heat, cold and disinfectants
25
vegetative vs endospore
• Vegetative Cell= actively growing and multiplying bacterial cells, do not contain endospores
• Endospore = dormant form of bacteria able to withstand environmental extremes
26
sporulation vs germination
• Sporulation=production of endospores, Sporulation takes place when certain nutrients are depleted. One copy of the genetic material and a tiny amount of cytoplasm is enclosed by a layer of insulating material and the whole structure is covered with several compact layers of spore coat
• When a favorable environment occurs the endospore can germinate and become active again
• Germination: A "viable" endospore is one able to germinate (grow) into a vegetative cell when moisture and nutrients are provided. One spore will germinate into one vegetative bacterium.
• Important virulence factor
27
• Two primary components of an endospore:
1) One copy of genetic material
2) Outer protective spore coat
28
endospore sterilization , 2 key
1. Endospores are quite resistant to heat. Most vegetative bacteria are killed by exposure to moist heat at 60 – 80°C for 10 minutes but spores will survive these high temperatures. Some spores are killed by boiling but others require a temperature of 121°C for 12 - 15 minutes for destruction.
2. Endospores are more resistant to disinfectants than vegetative bacteria. Low level disinfectants may not kill endospores and high-level disinfectants require extended exposure times
29
1.4 Binary Fission, what it is and steps
• Process of bacterial cell reproduction
-elongation, DNA replication, polar attraction, separation by a cell wall
30
generation time and slow vs fast
• Generation Time = time required for binary fission to occur and the population to double, affected by temperature and available nutrients, related to the rate at which bacteria cause disease.
Rapidly growing bacteria have a generation time of 15-30 minutes
Slow growing bacteria can have a generation time of 12-24 hours (or more!)
31
colony
The generation time also determines the amount of time required for bacteria to form visible growth on culture media. A “colony” is a visible mass of bacteria that develops on the surface of a solid culture medium after a period of time and represents all the descendants of a single bacterial cell.
32
Bacterial Growth Curve
lag, log, stationary, death, convalescnece for humans
33
lag
• Bacterial cells adapting to new environment
• Usually a few hours (2)
• LAG = no symptoms (incubation of organism)
34
log
• Maximum growth period where all cells are dividing at a constant rate (exponential growth)
• Symptoms = Acute stage of infection
• If left out of control patient would die during this phase
35
stationary
• Exhaust in supply of nutrients therefor halting growth
• Bacterial end products accumulate and prevent further growth
• Number of live bacteria stays constant
• Symptoms = no worse at this stage but no sign of recovery
36
death
• Death of bacteria, not host
• Bacteria start to die quickly
• Endospore formation occurs at this time, survive the longest
• Symptoms subside and recovery starts.
37
CONVALESCENCE STAGE
• Patient experiences complete recovery during this stage
• Can occur over a short period of time or a long period of time
38
virus replication lots steps 8:
• Virus locates matching host cell receptor on cell surface and attaches to cell
• For the Adenoviruses causing colds, the complementary sites are located on epithelial cells of the respiratory tract while the HIV virus which causes AIDS attaches to receptor sites of specific white blood cells called lymphocytes
• Once the virus attaches to the receptor, the host cell welcomes it inside (engulf/endocytosis)
• Cell realizes intruder presence and breaks down the protein coat of the virus, releasing free floating genetic material
• Viral DNA or RNA heads to host cell nucleus for replication
• Host cell enzymes and metabolic pathways hijacked for use by virus
• Viral proteins are produced in cytoplasm
• Viral DNA/RNA produced in the nucleus
39
2 effects of virus on cell host
• Cell death
-Viral replication until host cell bursts (lyses)
-Destruction of virus infected cell by body’s immune system (lymphocytes)
• Oncogenic tumor cell (oncogenic viruses, ex Hep B)
-Infect but do not kill the host cell
-Virus establishes long term/persistent infection
-Alters the cell’s genetic material to create a tumor cell
40
how to control viruses, 2 antiviral ex
• NOT ANTIBIOTICS: Antibiotics have no effect on viral replication. This is because antibiotics are directed against metabolic pathways of bacteria and since viruses have no metabolic activities of their own, antibiotics provide no antiviral activity
• Hard to find drugs to target viral replication that won’t kill the host cell
• Examples of antivirals:
Acyclovir – controls genital Herpes, Zidovudine (ZDV) – control HIV virus
41
generation time is affected by
temp and nutrients
42
lytic cycle vs lysogenic cycle
The lytic cycle involves the reproduction of viruses using a host cell to manufacture more viruses; the viruses then burst out of the cell. The lysogenic cycle involves the incorporation of the viral genome into the host cell genome, infecting it from within
43
What about its target makes HIV such a dangerous virus to humans
targets lymphocytes, immune cells
44
Normal Flora
• Established bacterial populations (skin/mucous membranes)
• Do not cause disease under normal circumstances
• Can cause disease if balance is interrupted
• Line of defense
• Help break down food/ digestion and evacuation
• most people basically have the same normal flora in the mouth. However, the normal flora composition varies depending on the site: normal flora of the mouth is different from normal flora of the intestine or the skin
45
area of the body having the greatest normal flora population
lrg intestine
46
normal flora in the upper resp do whar
occupy attachment sites on host cells and prevent pathogenic bacteria from invading respiratory tissue
47
flora and babies
• Placental barrier prevents microbial penetration
• Babies born with little-no normal flora
• Exposed to bacteria through:
birth, touch, milk, environment
48
where does normal flora establishes 4 key
• skin and mucous membranes lining the gastrointestinal, respiratory, and genital tracts.
49
• 3 Factors Affecting Normal Flora
-Excess moisture on skin, allows more
-natural body barriers
-antibiotic use, kills some-other dominate
50
contamination vs colonization vs infection vs disease 2 key each
Contamination
Foreign bacteria not usually present
No growth or damage; easily removed with washing
Ex: saliva on skin, dirty hands after changing diaper
Colonization
Contamination that results in growth
Causes no damage initially, but may lead to infection
Ex: Typhoid Mary, shunt colonization
Biofilm
Infection
Invaded, but no sign of lasting host damage (localized damage only)
Ex: STI, fish bite on finger
Disease
Host infected and injury evident and measurable
Ex: AIDS, tuberculosis
51
●non- low grade-pathogen
Non- Pathogen: Unable to cause disease
Low Grade Pathogens: Opportunistic, No disease unless host defense is broken or weakened
Pathogens : Disease causing organisms
52
● 4 virulence Factors:
○ Enzymes
○ Substances that can destroy RBCs
○ Substances that can destroy WBCs
○ Capsules
53
exotoxin vs endotoxin 2 key each
• Produced by Gram positive bacteria
• Intact bacterial cell releases toxin
• Affects area AWAY from site of infection
• Transported by blood or nerve cells
• Ex: Tetanus (Lockjaw)
Endotoxins
Produced by Gram negative bacilli
Released only when the bacterial cell wall is disrupted
More generalized effect on host (fever, chills, aches, general malaise)
Ex: E. coli 0157:H7 (Hamburger disease) causes Hemolytic Uremic Syndrome (HUS)
54
5 steps in the chain of infection
Infectious agent , Source of Reservoir (a pathogenic organism), means of transmission, susceptible host, portal of entry
55
Source of Reservoir: 3, 1 key each
Human Reservoir
● Principal reservoir is the human body
● Active Disease
● Carriers:
○ Convalescent Carrier (before 6 months/ when getting better)
○ Chronic Carrier (>6 months)
Animal Reservoir
● Zoonosis are diseases found in animals that can be transmitted to humans
● Ex: Salmonella, Rabies, Black Plague, Hanta virus
Non-Living Reservoir
o Found in the environment (soil and water) and most do not cause disease
o Ex: Tetanus, Botulism
56
3 Modes of Transmission
Contact ,vehicle, vector
57
4 contact transmission , describe each
: direct, indirect, droplet m airborne
physical contact, fomite, mucus droplets < 1 m, droplet nuclei
58
Vehicle Transmission 2 and describe
water/food, contamination
food, droplet nuclein - tb, measles, chicken pox, contaminated blood products
59
vector tramission
o Insects that carry infectious organisms from one host to another
o NOT a mode of transmission within the hospital however patients within the hospital may have been infected by vectors before arriving
60
Susceptible Host
Host susceptibility determines whether an encounter with an infectious microbe will result in disease. Host susceptibility is influenced by a number of factors including age, health, and immune status of the individual, as well as the dose of the infectious agent to which the individual is exposed.
• newborns whose immune systems are not fully developed and the elderly whose immune systems are not functioning properly
• a person's resistance to infection is impaired by factors such as poor nutrition, alcoholism, pre-existing infection, and underlying disease
• therapeutic measures such as chemotherapy, radiation, and antibiotics alter the immune status of the individual
• procedures such as surgery, anaesthesia, and insertion of catheters
• the infectious dose. The infectious dose for Salmonella bacteria is about 100,000 organisms; for Shigella (bacteria that cause dysentery), the infectious dose is much lower - somewhere between 10 and 100.
An individual who has received a vaccination against a disease-causing microbe, or someone who has recovered from a particular infection, will have produced antibodies against the pathogen and will be a less susceptible host on subsequent exposures to the microorganism
61
Portals of Entry 3 main ones
– Skin/ Mucous membrane, placenta, parenteral -blood
62
skin entry
● Via hair follicles and sweat glands
● Excessive moisture on the skin
● Broken skin
● Outer skin disruption
Hot Tub Folliculitis
Boils
63
3 mucous membranes entry
• Respiratory Tract: Influenzae
• Gastrointestinal Tract: Salmonella, Hepatitis A
• Genital Tract: Herpes, Chlamydia, HIV
64
placenta entry
• Generally filters mom’s blood to prevent microorganisms from infecting baby
• Exceptions: Rubella, Hepatitis B, HIV
65
Parenteral (outside of the gastrointestinal )
● Passage or transfer of potentially dangerous pathogens via a way other than through the digestive system
● Includes: intravenous injection of contaminated substance, punctures, bites, cuts, surgical wounds and trauma injuries
66
How Can We Break the Chain ?
Breaking the chain of infection means stopping infections at the source, eliminating means of transmission, or reducing the susceptibility of potential hosts. Most infection control programs are directed towards preventing transmission and include procedures such as proper hand washing; use of gowns, gloves, masks and other protective equipment when indicated; proper waste disposal; isolation procedures; and decontamination of equipment and surfaces. Susceptibility of potential hosts can be reduced through proper nutrition, reduction of stress, and immunization procedures.
67
indications of infection may be manifested 3 key
fever, lymph node swelling, and inflammation
68
signs vs sypmptoms
Sign:
• Observed
• Fever, redness, swelling, high blood pressure
Symptom:
• Felt by the patient
• Pain, nausea, malaise, headache
69
fever caused by 3-4
↑ 1˚C above normal (36.1 - 37.8˚C)
Caused by 4 things:
○ Chemical substances from microorganism
○ Constriction of blood vessels
○ Increase metabolic rate (may facilitate phagocytosis and tissue healing)
○ Shivering (inside warmer but skin still cold so you shiver to increase)
70
when fevers gets better/ heat loss 2 ways
When the chemicals triggering the temperature increase are removed, the thermostat setting returns to normal and the body experiences heat loss. Blood vessels dilate (widen) allowing more blood to circulate close to the skin surface to lose heat. This is accompanied by sweating, another heat loss activity and an indication the fever has broken.
71
Lymph Node Swelling, what is it, 2 vs 1
Lymphatic System
• Complex series of vessels that drain fluid (lymph) from tissues and return it to the blood stream
• Filtering system
Lymph Node Swelling
• Microbes that are infecting node
• Multiplication of lymphocytes
• Single Swollen Node= Node Infection
• Multiple Swollen Nodes= Immune System Response
72
lymph found in 3 areas
A) Cervical – Neck
B) Axillary – Armpits
C) Inguinal – Groin
73
4 cardinal symptoms of inflammation
Heat-Redness-Swelling-Pain
74
inflamation 3 steps
1. Tissue injury: release of chemical signals, histamine initiates inflammation
2. Dilation and increase leakiness of local blood vessels migration of phagocytes to the area
3. Phagocytes (macrophages and neutrophils) consume bacterial and cell debris tissue heals
75
Clearing the Infection 4 main
o ↑ phagocytic WBCs resulting in leukocytosis (increased WBCs in the bloodstream)
o Already-formed antibodies gather at injury site and coat bacteria
o Clotting factors gather at injury site and trap bacteria in fibrin clots
o Appearance of purulent exudate/pus- This represents phagocytic white blood cells that have been killed in action.
76
terms : acute, chronic, latent, localized infec, focal infec, system infec, septicimeia, bacteriumia, viremia, tozemia, exogenous and endogemous infec, primary and secondary infec
Ex for each
Acute Disease
• Symptoms develop quick + disease course is quick
• Ex: Common Cold
Chronic Disease
• Symptoms develop slowly + slow recovery
• Ex: Tuberculosis
Latent Disease
• Periods of inactivity/no symptoms between episodes
• Ex: Herpes
Localized Infection
• Confined to one area of the body
• Ex: Strep throat
Focal Infection
• Confined to a specific area, but bacteria and/or toxins can spread to other areas
• Ex: Abscessed tooth
Systemic Infection
• Affected multiple organism or tissues
• Ex: HIV
Septicemia
• Presence and multiplication of bacteria in bloodstream
Bacteremia
• Transient presence of bacteria in bloodstream, without multiplication
Viremia
• Transient presence of virus in bloodstream, without multiplication (chicken pox)
Toxemia
• Presence of toxins in the blood
Exogenous Infection
• Organisms causing infection is from outside host (another animal/human/environment)
• Ex: Cat scratch causes wound infection
Endogenous Infection
• Organism that is normal flora on one part of the body causing infection elsewhere
• Ex: fecal bacteria causing UTI
Primary Infection
• Infection in previously healthy individual
Secondary Infection
• An infection immediately following a primary infection
• Ex: sick with the flu get bacterial pneumonia
77
Nosocomial Infections, 2 key issues
• Infections acquired while at a hospital or other health care facilities
• 5-15% of patients
• Bacteria brought into hospital by patients from outside world
• Warm moist conditions perpetuate growth
• Antibiotic resistant strains survive better in hospitals
78
Transmission of Nosocomial Infections 3 main
Hospital microorganisms, transmission, compromised patients
79
common nosocomial infec 3 main, 3 ex
Urinary Tract Infection (UTI)
o Most common
o E. coli from fecal flora colonizing catheter
Surgical Wound Infections
o Staphylococcus aureus from hospital staff (60% of people are carriers)
Pneumonia
o Pseudomonas aeruginosa in people on respiratory ventilators
o High mortality rate
80
anitbiotic res 2 reasons
Antibiotic Resistance
• Problems:
○ Limited options for treatment
○ More expensive
○ More toxic
○ Healthcare facility risks
• Why?
○ over-prescribing
○ Patients not completing courses of antibiotics
--also when taking antibiotics some bacteria persist/ dominate and pass on dna , Drug resistance that develops in harmless bacteria may be transferred to harmful microbes.
81
2 main Hospital “Superbugs”
they are no more virulent than regular Staphylococcus aureus or Enterococcus sp. However, infections with these bacteria are more difficult and expensive to treat.
MRSA: (Methicillin resistant Staphylococcus aureus)
VRE (Vancomycin resistant enterococcus)
82
MRSA, transmission /colonization / prevention
o Transmission
o Generally direct contact (surgery)
o Colonization
o 1 in 50 people are carriers
o Prevention
o Identify cases
o Isolate cases in-hospital
o Identify healthcare carriers
o Treat carriers
o Hard to eradicate from Healthcare facility once established
83
vre transmission /colonization / prevention
o Transmission
o Contact (people or equipment)
o Can survive up to 7 days on surfaces
o Colonization
o Those previously treated with vancomycin
o Long term hospitalization with long antibiotic treatments
o Catheterized patients
o Immunocompromised
o Prevention
o Identify cases
o Handwashing
o Rigorous decontamination of rooms/equipment
o Using more specific antibiotics on hospital patients when possible
- Vancomycin-resistant strains of Enterococcus are often resistant to almost all available drugs, so if the patient does have an infection with one of these strains, it may be untreatable and potentially fatal
84
Infection Control Committee
Hospitals require monitoring of nosocomial infections
• Surveillance
• Watch for increase in infections, particular wards, new resistant bacteria
• Investigate and control outbreaks
• Implement preventative procedures
• Educate
• Develop policies
• Consultation with hospital and community
National Statistics (IPAC – Canada) monitor epidemiology
85
Immunization is a process by which
resistance to an infectious disease is induced or augmented
Importance of immunization – You as a HCW vs. patient
86
Antigens/immunogens
trigger an immune response, composed of protein, but polysaccharides and combinations of polysaccharides and proteins may also be antigens
87
ANTIBODIES (GAMMA GLOBULINS/ IMMUNOGLOBULINS) type of whihc imunity ?
humoral
88
IgM vs IgG
IgM first
• Largest antibody molecule
• Short-lived defense
IgG after IgM
• Much smaller
• Long lasting immunity (memory)
• Can cross placenta
89
antibodies found where?
IgM and IgG are found in the blood and other body fluids and make up the humoral immunity of the host
Humoral immunity:
immunity due to the macromolecules in the body's extracellular fluid
90
• Two types of lymphocytes:
• B cells responsible for humoral immunity or antibody production
• T cells help other immune cells and kill virally infected cells and tumours
91
antibody prodction 4 steps
foreign micro enters
macro send antigen infor to WBC in lympahtic system
b cell makes contact with antigen on macrophaed and acitvates
b cell duplicates to make memory b cell and plasma cell
92
Immunization Response
• Generally a series of shots (2 or 3, depending)
• First exposure to antigen rarely produces protective levels of antibodies
• 2nd/3rd injections generate high levels of antibodies
93
Factors affecting response to immunization 4:
• Individual Differences
– Inheritance
– Disease affecting immune system
– General health
• Site of Injection
– Intramuscular, Subcutaneous, Nasal Spray (fat may trap antigen)
• Immunization Product
– Goal = ↑ Antibody Response, ↓ Adverse Reactions
• Product Failure
– Faulty lot #
– Improper storage
94
3 Products used for immunization
• Vaccines- viral and bacterial immunizations
• Toxoids
• Preformed antibodies
95
Vaccines are
A suspension of altered bacteria/virus that can induce immune response but not cause disease
96
5 types of vaccines
• Killed/Inactivated- killed using formalin
• Acellular (Subunit, recombinant, polysaccharide, and conjugate vaccines)- antigenic part of the organism is used, ie protein
• Live-Attenuated- weakened by aging it or altering its growth conditions.
• mRNA vaccines are easy and inexpensive to make — and pose no risk of infection.
• Viral-vector vaccines act like a natural infection, so they're especially good at teaching the immune system how to fight germs. Adenovirus
97
Toxoids are
• Extracted bacterial exotoxin that is treated so it is no longer toxic
• Induce weak immune response unless administered with another agent
• (Combo-vaccine like DPT – Diphtheria/Pertussis/Tetanus)
98
Passive immunization
“Loaner” antibodies (IgG)
Short-lived immune response
Used for disease treatment or short-term disease prevention
Different forms:
• Immunoglobulin
• Antiserum
• Antitoxin
99
passive vs active vs artificial vs natural
exposure to antigen vs give ab vs given antigen on purpose vs exposed naturaly
Active Immunity
• the individual is given or exposed to an antigen which triggers the immune response
• the individual produces their own antibodies
• takes days to weeks to establish protection
• used for disease prevention
• immunization agents that induce active immunity are vaccines and toxoids
• immunity is long lasting
Passive Immunity
• person acquires preformed antibodies
• the antibodies are available immediately to provide protection
• used primarily for disease treatment, or in a few cases, short term prevention
• immunization products that provide passive immunity are various immune globulins, antitoxins, and gamma globulin
• immunity does not last long
Artificially Acquired Immunity
• antigen is administered deliberately to induce immunity
• usually means an injection with a needle although there is a polio vaccine given orally
Naturally Acquired Immunity
• a consequence of a natural process such as having a disease, or the maternal transfer of antibodies from mother to fetus via the placenta or from mother to newborn via breast milk
100
Immunization practices childhood immunity , when and what is normal
• Newborn’s immune system is not fully developed at birth (rely on circulating maternal antibodies)
• After 2 months, immune system is functional, and vaccines begin
• Vaccinations include:
– Diphtheria, pertussis, tetanus, poliomyelitis, Haemophilus influenzae type b, rotavirus, measles, mumps, rubella, varicella, pneumococcus, and meningococci
101
Rubella, German measles
• Signs: rash on face that rapidly spreads to neck and trunk lasting 2-3 days
• Virus can cross the placenta, which can result in fetus abnormalities including:
– Stillborn or spontaneous abortion
– Deafness, cataracts, developmental delays and heart defects in newborns
• Given in combination with Measles and Mumps (MMR)
• Mandatory for health employees in some provinces
102
Hep B
• Hepat – itis = liver inflammation
• Infectious body fluids = blood*, saliva, vaginal secretions, semen, CSF, peritoneal, pleural and amniotic fluid
• Healthcare workers at risk of blood or body fluid exposure should be immunized
• Immunization = 2 injections 1 month apart + 3rd injection at 6 months into deltoid muscle (adults/children) and into anterolateral thigh muscle on infants
• The second product available for protection of health care workers is hepatitis B immune globulin (HBIG). This product contains preformed antibodies to hepatitis B and is a form of passive immunization.
How do I know if I am immune?
• No detectable immunity until after 3rd dose
• Blood is checked for antibody production (anti-hepatitis B surface antibodies – antiHBs)
• Now part of childhood immunizations (10–12-year-olds)
Heb B immune globulin HBIG
• Preformed antibodies given to:
– healthcare worker after blood or mucous membrane exposure when there is no evidence of vaccination or anti-HBs
– Babies born to Hep B positive mothers (+ Hepatitis B vaccine)
• Should be given within 48 hours of exposure
103
Tetanus:
ever 10 years
104
Varicella Zoster chicken pox
• Incubation period = 2-3 weeks
• Signs/Symptoms = fever, malaise, vesicular eruptions (more severe in adults)
• ITCHY!
• Can cause pneumonia and encephalitis (more so in immunocompromised)
• Proof of immunity required for most healthcare workers (proof of clinical hx or varicella IgG)
• Workers without immunity can then be kept away from patients with chicken pox or shingles.
105
Zoster shingles
• Reactivation of latent chicken pox virus
• Signs/Symptoms= painful lesions of peripheral nerve endings (torso, neck or face[ocular])
106
Flu vaccines -
over 65/ critically ill
- Elderly ,young, immunocompromised and healthcare workers advised to get the influenza vaccine every year.
- Usually made up of 3-4 different inactivated viruses that are anticipated through epidemiology to cause problems in the next year. It is therefore not 100% as it is a prediction and will not protect against other Flu viruses.
107
Tuberculin testing
• Highly infectious bacteria (Mycobacterium tuberculosis) that spreads from person to person by inhalation of droplet nuclei released into air by coughs and sneezes
• New, antibiotic-resistant forms are being discovered
• Although decreased rates in Canada, still a global concern
• Treatment up to 12 months , most don’t become active cases
-tb has resistant forms
108
Minimize risks of TB
• Recognize high risk patients
-understand transmmission
• Recognize high risk patients
– People at largest risk in Canada:
• Foreign-born individuals
• Indigenous population
• Poor/Homeless
• Patients addicted to drugs or alcohol
• Elderly
• HIV/AIDS patients
• Understand transmission
• Spread by droplet nuclei-inhalation of airborne nuclei is the greatest threat
• Negative pressure room
• Patient =surgical mask
• Healthcare team=glove/gown/N95 mask
109
TB inacitve, delayed acitvity, acitvity
no symp vs no initial symp-ab made vs symptoms presist
110
TB skin test/ Mantoux test
• Intradermal injection of TB protein
• Observation for hypersensitivity (immune response) 48-72 hours later
111
• Reasons for a positive TB test: 4
– Person has ACTIVE tuberculosis
– Person has been IN CONTACT with someone who has active tuberculosis
– Person has PREVIOUS HAD Tuberculosis
– Person has been IMMUNIZED against tuberculosis
112
review all glossery
113
Histamine results in
Histamine results in:
• vasodilation (widening of the blood vessels) which increases blood flow to the injury site resulting in heat and redness
• increased permeability of the blood vessels, causing fluid to leak from the vessels into the surrounding tissues creating swelling and pain
114
1mm and 1 cm = x um
1000 , 10,000
115
True or false
one bacterial cell forms one endospore
True
116
True or false
one endospore germinates to one bacterium
True
117
E. coli in water
Fecal source
118
Pyrogens
Endotoxins
119
T or f
Both exotoxins and endotoxins effect away from site
True
120
Do exotoxins attak specific ?
Yes
121
Unlikely to see spores
Log
122
All microorganisms are smaller than
All microorganisms are
smaller than 0.1 mm (100 μm)
