Unit 3: Infectious Diseases and STIs Flashcards
State the name of the process in which infectious diseases are transmitted.
Name each link and state the example of the Flu
Chain of infection
pathogen: microorganism that causes disease - HIV, cold, influenza
reservoir: the natural environment that the pathogen lives in - Human
portal of exit: the way that the pathogen leaves the reservoir - saliva blood, nose and throat discharges (sneezing, coughing)
means of transmission: how the pathogen is passes from original to new host -
direct: sneezing and discharging infectious particles into air, inhaled by someone nearby
indirect: mosquitoes
portal of entry: the way that the pathogen enters a new host - pathogens entering through a lesion in the skin
new host - 2nd human
What are the components of the 1st line of defense against infection?
How does mucous and cilia work together?
Skin, mucous membranes, cilia, elevated body temperature
Mucous traps pathogens, and cilia sweep them out.
What is the 2nd line of defense against infection?
What do they do in regard to pathogens?
Immune cells
Recognize pathogens as foreign due to antigens and may destroy them depending on type of cell.
Name the five types of white blood cells.
Explain where each is found and what they do.
- Neutrophils: travel in bloodstream, attack and ingest pathogens
- Macrophages: stationed in tissues, devour pathogens and worn-out cells
- Natural killer cells: develop in bone marrow and other places, directly destroy virus-infected and cancerous cells
- Dendritic cells: reside in tissues, eat pathogens and activate lymphocytes
- Lymphocytes: found in bloodstream and lymphatic system, destroy and recognize virally infected
What are the 2 main types of lymphocytes and what do they do?
T-cells: recognize and kill virally infected
B-cells: produce antibodies which bind and stick to antigens
What are antibodies?
Proteins that recognize foreign substances and neutralize them
Describe the inflammatory response.
What are some effects?
Response towards injury or infection
Special cells in area of invasion or injury release histamine, causing blood vessels to dilate and fluid to flow out of capillaries into injured tissue
- Produces increased heat, swelling and redness
- WBC drawn to area and attack invaders (sometimes there’s pus, a collection of dead WBC and debris)
What are the two types of immune response?
Explain both.
- Natural (innate) response
- Acquired (adaptive) response
Natural
* neutrophils, macrophages, dendritic cells and natural killer cells recognize pathogens and eat/destroy them
- have no memory of past infections, have same response no matter how many times a pathogen invades
Acquired
* T and B cells change, developing emmory for antigen
* If body is invaded again, they recognize the pathogen and scale to a much mroe potent response
Which white blood cells are involved in the cell-mediated response?
T cells
Which white blood cells are involved in the antibody-mediated (humoral) response?
Macrophages and B cells.
What are the six major types of pathogens?
- Bacteria
- Viruses
- Fungi
- Protozoa
- Parasitic worms
- Prions
Describe bacterial pathogens.
What type of cells? Most are _?
Single-celled organisms, mostly safe, approximately 1% are harmful.
How do bacterial pathogens cause harm?
By releasing toxins/enzymes.
What is usually used to treat bacterial infections?
Antibiotics.
What are examples of bacterial diseases?
Meningitis, orchitis, UTIs
What is meningitis?
State some symptoms.
infection of meninges (membranes covering the brain and spinal cord)
fever, confusion, stiff neck
What is orchitis?
State some symptoms.
Penile infection
redness, irritation, pain during urination/intercourse
What are UTIs
State some symptoms.
Urinary Tract Infections
burning, fever, blood in urine
Describe viral pathogens.
Infectious agents consisting of a protein enclosing DNA/RNA.
What is usually used to treat viral infections?
Antiviral drugs.
What are some examples of viral diseases?
Common cold, flu, hepatitis
What are symptoms of the common cold?
Runny nose, cough, sore throat.
Describe the flu in terms of mutation
High rate of mutation
What is hepatitis?
What are symptoms? How is it transmitted?
Inflammation of the liver
Symptoms: high fever, jaundice (yellow skin)
Hep A/E transmitted through water
Hep B/C/D transmitted through hanky
What do fungal pathogens to its host?
What does this cause?
Absorb nutrients from the host
Causes cell damage
What is an example of a fungal infection and its symptoms?
(type of yeast infection)
Candidiasis: itching, burning, discharge.
How do protozoan pathogens destroy cells?
By releasing enzymes/toxins.
State examples of protozoan pathogens
- Trichomoniasis
- Malaria
What is trichomoniasis?
Vaginal yeast infection
Describe what parasitic worms do to their host?
Attack tissues/organs and compete for nutrients
Parasitic worms
What are examples of portals of entry?
- Consumption of infected food and water
- Enter by burrowing through skin
What are examples of parasitic worms?
- Tapeworms
- Schistosoma
Tapeworms can be from beef, pork, or fish.
What are prions?
Proteinaceous infectious particles.
What do prions do specifically to the body?
Form deposits in the brain.
What are examples of prions?
- TSEs
- Mad cow disease
Prions
What are TSEs?
Symptoms?
Sponge-like holes in the brain
loss of coordination, weakness, dementia, death
How many people were infected by the spanish flu?
50% of the world’s population
Why were mostly 18-40 year olds infected during the Spanish flu?
Immune systems went into overdrive (cytokine storm).
What is measles known as?
“Most deadly of all childhood rash/fever illnesses.”
What are steps to prevent infections?
- Wash hands often
- Get adequate sleep and exercise
- Eat a balanced diet
- Avoid sharing food and drinks
- Practice safe sex
- Avoid rubbing eyes and touching face
- Limit # of sexual partners
What has caused antibiotic resistance?
(Pharmacy)
Natural selection and overuse of antibiotics.
What are steps to prevent antibiotic resistance?
- Let your immune system work
- Finish the entire antibiotic regimen
- Don’t share antibiotics
- Avoid antibiotic soaps and cleansers
What is Chlamydia known for?
Who is it 2x more likely to occur in?
Most common bacterial STI reported in Canada.
Women
What are symptoms of chlamydia?
Is it usually asymptomatic or shows symptoms?
Discharge and burning, but often asymptomatic.
What are risks of untreated chlamydia?
- Ectopic pregnancy (sterility)
- Can be passed to infants
- PID (pelvic inflammatory disease)
What can prevent chlamydia and how is treated?
Prevention: condom use
Treatment: Antibiotics
What is gonorrhea known as?
2nd most commonly reported bacterial STI in Canada.
What are symptoms of gonorrhea?
Is it asymptomatic or often shows signs?
Often asymptomatic in women; urinary discomfort and penile discharge in men.
What are the three stages of syphilis?
Is it bacterial or viral?
- Primary: ulcer
- Secondary: flu-like and rashes
- Tertiary: neurological and cardiovascular effects
Bacterial
How is syphillis transmitted?
passes through break in skin - kissing, sex
What is HPV known for?
(human pappiloma virus)
Most common viral STI in North America.
What is are risks of HPV?
Common and genital warts
Genital, vaginal, anal, vulvar, penile, and oropharyngeal cancer
How is HPV prevented and how is it usually treated?
Prevention: Gurdasil vaccine
Treatment: Immune system usually clears infection
Where is HSV usually located?
(herpes simplex virus)
How does it travel in the body?
Common oral
Travels along nerves and lays dormant in nerve cells
What are symptoms of HSV? HSV1 vs HSV2?
Small, painful, leaking red blisters
HSV1: mouth
HSV2: genitals
What prevents HSV?
Since it can’t be treated, what is used to lessen symptoms?
Condom use
Antivirals
What does HIV attack?
(human immunodeficiency virus)
What does this do?
T cells.
Overwhelms immune system
How is HIV transmitted?
Blood-blood or fluid-blood contact.
What are risks associated with HIV?
AIDS and death due to infections.
Name treatments for HIV
- HIV testing
- HAART
- Combo of drugs for each level
What does HIV testing measure?
Antibodies.
What are risk factors for STIs?
- Multiple partners
- Not using protection
- Lack of testing
- Unaware of partners history
