Contact Infectious Disease Flashcards
Describe this Contact Infectious Disease: Trachoma (Non-sexual disease)
(Causative Agent/Characteristic, Virulence Factors, Reservoir, Mode of Transmission, Predisposing Factors, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristc
- AKA: x
- CA: Chlamydia trachomatis strain (different serotype than Genital Chlamydia)
- Characteristic: Gram-negative, coccobacillus, obligate intracellular parasite
Virulence Factors
- Invades and Replicates in epithelial cells
- 2 morphological forms
-> Elementary bodies:
–» Infectious, invade epithelial cells
-> Reticulate bodies:
–» Non-infectious, replicate intracellularly
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Direct: Hand-to-eye contact
-> Eye discharge - Indirect: Sharing objects
-> Towels/handkerchiefs - Arthropod: Sand Flies
-> Carrying eye discharge
Predisposing Factors
- Unsanitary conditions
- Over-crowding
- Children
Incubation Period
- x
SXS
- Inflammation (conjunctivitis) of upper eyelid
-> scarring/contraction of conjunctiva -> eyelashes turn inward -> eyelashes scratch cornea -> corneal cloudiness -> permanent blindness
Diagnosis
- Clinical/SXS
Treatment
- Surgery
- ABX
Preventative Measures
- No vaccine available
- Vector control of sand flies
- Washing hands
MISC
- POE - mucous membrane (conjunctiva)
- Leading preventable causes of blindness worldwide
- Most cases of blinding trachoma occur in Africa
-> HIGH infection rates < 5yr
Describe this Contact Infectious Disease: Gonorrhea
(Causative Agent/Characteristic, Virulence Factors, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Neisseria gonorrhoeae
- Characteristic: Gram-negative, encapsulated diplococcus (coffee-bean)
Virulence Factors
- Capsule & Fimbriae
-> attaches to epithelial mucosa - Op proteins in CW
-> Bind to T cell receptors -> inhibit immune response
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Direct: sexual contact
Predisposing Factors
- x
Incubation Period
- x
SXS
- Gonococcal Urethritis (caused by N. gonorrhea)
- Men: (More SXS)
-> Painful urination
-> Creamy, yellow discharge
-> Epididymitis (testicular pain) - Women (Few/No SXS)
-> Pelvic inflammatory disease (PID; inflammation of ovaries/fallopian tubes = major cause of sterility)
MAY BECOME SYSTEMIC IF UNTREATED:
-> Endocarditis (heart inflammation)
-> Meningitis (brain/spinal cord membrane inflammation)
-> Arthritis (joint inflammation)
Infants:
-> Ophthalmia neonatorum (neonatal conjunctivitis)
–> Infant blindness bc gonorrhea/genital chlamydia inf of eyes during vaginal birth
Diagnosis
- Urine test or oral/urethral-rectal swab
- PCR
- Culture (look for gonococci)
Treatment
- ABX
-> Injection
-> Oral meds
Preventative Measures
- Education & safe sex practices
MISC
- Highest infection rates in teens/young adults (bc sexually active)
- Coinfection with Genital Chlamydia
Describe this Contact Infectious Disease: Genital Chlamydia
(AKA/Causative Agent/Characteristic, Virulence Factors, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: Chlamydia
- CA: Chlamydia trachomatis strain (different serotype than Trachoma)
- Characteristic: Gram-negative, coccobacillus; obligate intracellular parasite
Virulence Factors
- Invades and Replicates in epithelial cells
- 2 morphological forms
-> Elementary bodies:
-» Infectious, invade epithelial cells
-> Reticulate bodies:
-> Non-infectious, replicate intracellularly
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Direct: sexual contact (through epithelial mucosa)
Predisposing Factors
- x
Incubation Period
- x
SXS
- Non-gonococcal urethritis (caused by N. gonorrhea)
- Men: (More SXS)
-> Painful urination
-> Watery, clear discharge - Women (Few/No SXS)
-> Pelvic inflammatory disease (PID; inflammation of ovaries/fallopian tubes = major cause of sterility)
May also cause (in infant):
-> Ophthalmia neonatorum (neonatal conjunctivitis)
–> Infant blindness bc gonorrhea/ genital chlamydia inf of eyes during vaginal birth
Diagnosis
- Nucleic Acid Amplification Tests (NAAT)
-> most sensitive test available
-> PCR is a type of NAAT
-> Performed on vaginal/urethral swabs or urine
Treatment
- ABX
Preventative Measures
- Education & safe sex practices
MISC
- Most common bacterial STD in U.S = millions cases (in US)
- Coinfection with Gonorrhea
Describe this Contact Infectious Disease: Syphilis
(Causative Agent/Characteristic, Virulence Factors, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Treponema pallidum
- Characteristic: Gram-negative, spirochete (endo flagella/axial filaments); motile
Virulence Factors
- Lipid outer layer
-> weak immune system
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Direct: sexual contact
Predisposing Factors
- x
Incubation Period
- x
SXS
Primary Stage/Phase:
-> Chancre (painless core at site of infection)
–» Highly infectious
Secondary Stage/Phase:
-> Flat, skin & Mucosal rashes
–» Palms & soles
-> Latent period: decades
Tertiary Stage/Phase:
-> Appears decades later after latency
-> Formation of gummas (soft tumor-like lesions) on bone, brain, heart & skin
-> Arthritis
-> Cardiovascular dmg -> cardiovascular syphilis
-> Neurological dmg, dementia -> neurosyphilis
Diagnosis
- Serology
-> Direct DXS: look for T. Pallidum
-> Indirect DXS: look for Ab
Treatment
- ABX
-> effective only in early stages
Preventative Measures
- Education & safe sex practices
MISC
- Congenital syphilis
-> Development damage to fetus & stillbirths
Describe this Contact Infectious Disease: Trichomoniasis
(AKA/Causative Agent/Characteristic, Virulence Factors, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: Trich
- CA: Trichomonas vaginalis
- Characteristic: Kingdom Protista, protozoan parasite; Motile: Flagella, undulating membrane; Pear-shaped
Virulence Factors
- Axostyle: sharp point for anchoring to epithelial cells
Tissue/Organ Affected
- x
Reservoir
- Men
Mode of Transmission
- Direct: sexual contact
Predisposing Factors
- x
Incubation Period
- x
SXS
- Men:
-> Asymptomatic carriers: found in urine & semen
-> Some urethral discharge
-> Painful urination - Women:
-> Symptomatic
-> Frothy, greenish-yellow, foul odor discharge
-> Painful urination
Diagnosis
- Microscopic observations of live, motile protozoa from swab of the infection site
Treatment
- Antiparasitic/antiprotozoal drugs
Preventative Measures
- Education & safe sex practices
MISC
- Most common non-viral STD in U.S = millions+ new cases/year
- Risk of low birth weight or premature births
Describe this Contact Infectious Disease: Genital Herpes
(Causative Agent, Virulence Factors, Reservoir, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Herpes Simplex Virus Type 2 (HSV-2), HHV; Herpesviridae family; DNA
- Characteristic: x
Virulence Factors
- Hide in NS = latent viral infection
Tissue/Organ Affected
- x
Reservoir
- Human
Mode of Transmission
- Direct: sexual contact
Predisposing Factors
- x
Incubation Period
- x
SXS
- Painful, fluid-filled/raised vesicles on the genitals
-> Heals within 2 weeks (not cured)
-> Outbreaks of vesicles; primary episode -> recurrent outbreaks - Painful urination
Diagnosis
- Culture
- PCR
Treatment
- Antivirals (management/suppress SXS)
Preventative Measures
- Education & safe sex practices
MISC
- 25% adults >30yr infected in U.S
- Neonatal Herpes:
-> Herpes crosses the placental barrier -> infects the fetus
-» Damage CNS = developmental delays, blindness, hearing loss
-> Low Survival rate (40%)
-> Newborns infected during delivery
Describe this Contact Infectious Disease: Hepatitis B
(Causative Agent, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Hepatitis B Virus: DNA
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- x
Mode of Transmission
- Direct: sexual contact (body fluids)
- Accidental needle sticks (healthcare workers)
Predisposing Factors
- x
Incubation Period
- x
SXS
Mild to Severe SXS:
Acute Infection:
-> Most adults fully recover
-> Jaundice
-> Loss of appetite
-> Fever
-> Nausea
-> Vomiting
Chronic Infection:
-> Liver failure
-> Cirrhosis
-> Liver cancer
Diagnosis
- Serology (Abs)
- Liver Ultrasound
- Liver Biopsy
Treatment
- NO CURE (management)
To manage chronic disease:
- Antivirals
- Interferon Injection
- Liver transplant
Preventative Measures
- Vaccine
- Education & safe sex practices
MISC
- Small % of infected patients -> chronic Hepatitis B
Describe this Contact Infectious Disease: Hepatitis C (NOT STD)
(Causative Agent, Mode of Transmission, SXS, Diagnosis, Treatment, Preventative Measures, Misc)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: Hepatitis C Virus: RNA
- Characteristic: x
Virulence Factors
- x
Tissue/Organ Affected
- x
Reservoir
- x
Mode of Transmission
- Contaminated blood
-> blood transfusions
-> tattoos
-> IV drug use
Predisposing Factors
- x
Incubation Period
- x
SXS
Acute Infection:
-> Most PT will develop chronic hepatitis
-> Usually asymptomatic
-> Jaundice
-> Loss of appetite
-> Fever
-> Nausea
-> Vomiting
Developed Chronic Infection:
-> Liver failure (~25%)
-> Cirrhosis (~25%)
-> Liver cancer
Diagnosis
- Serology (Abs)
- Liver Ultrasound
- Liver Biopsy
Treatment
- NO CURE (management)
- Daily Antiviral: 2-6mnth
-> Can help 95% of people
-> Notoriously expensive ($1000/pill)
-> Virus is undetectable in blood - Liver transplant
Preventative Measures
- NO VACCINE
- Universally safe precautions/blood handling
MISC
- Large % of infected patients -> chronic Hepatitis C
- Large % of PT with Hepatitis C were born ~mid 1900’s
Describe this Contact Infectious Disease: HIV/AIDS
(Causative Agent/Characteristic, Virulence Factor, Mode of Transmission, Predisposing Factors, SXS, Diagnosis, Treatment, Preventative Measures)
AKA/Causative Agent/Characteristic
- AKA: x
- CA: HIV (human immunodeficiency virus), Retroviridae Family, Retrovirus, RNA
Two strains: HIV-1 (more deadly) & HIV-2 - Characteristic: Enveloped, spikes (gp120; attach to host cell), enzymes (reverse transcriptase, integrase)
Virulence Factors
- High gene mutation
-> Rapid antigenic variation - Targets human host cells: CD4+ T cells (surface marker on T helper cells) = destroy Cell-Mediated Immunity
Tissue/Organ Affected
- x
Reservoir
- x
Mode of Transmission
- Primary method: sexual contact
-> Exchange body fluids - Secondary method: non-sexual contact
-> Blood (contaminated) transfusions/organ transplant
-> Breast milk
-> Transplacental
-> Sharing contaminated IV needles (HIV-contaminated blood)
Predisposing Factors
In chronological order from most to least:
- Men having sex with men (MSM)
- Heterosexuals
- IV drug users
- MSM and IV drug users
Incubation Period
- x
SXS
Viremia (Sys inf):
Phase 1:
- Asymptomatic
-Hardened, swollen lymph nodes = lymphadenopathy
Phase 2:
- Serious disease SXS
-> Persistent Candida albicans (fungal) infections
-> Persistent diarrhea
-> Fever
Phase 3:
- Clinical AIDS indicator Conditions unusual opportunistic infection (bc weak immune system)
-> Atypical (fungal) Pneumonia
-> Kaposi’s Sarcoma (cancer of the skin and BV; HHV-8)
-> Miliary TB (Sys TB infection)
Diagnosis
- ELISA
-> Detects pathogen or Ab - Plasma Viral Load
-> Detects & quantifies the amount of HIV circulating in the blood - Rapid tests & self-testing Kits
-> Detects HIV ab in saliva
-> Results available in 20 minutes
Treatment
- NO CURE
- Anti-Retroviral drugs/therapy (ART) - management
-> HAART
-> Fusion/Cell Entry Inhibitors
-> Reverse Transcriptase Inhibitor (2 types)
-> Integrase Inhibitors
-> Protease Inhibitor
Preventative Measures
- NO VACCINE
- Education & safe sex practices
- PrEP (Pre-exposure prophylaxis)
-> Sold under the name Truvada
MISC
- x
What does HIV stand for? What does AIDS stand for?
HIV = human immunodeficiency virus
AIDS = acquired immunodeficiency syndrome
Generally describe how HIV/AIDS became known as. Include specific dates
1981: cluster of Pneomocytis (atypical) pneumonia, Kaposi sarcoma (cancer), and loss of immune function were discovered in young, homosexual men. AIDS EPIDEMIC BEGINS
1982: term Acquired Immunodeficiency Syndrome is used for first time
1983: discovery of virus causing the loss of immune function -> eventually named Human Immunodeficicy Virus (HIV)
HIV/AIDS spread from “__________” ________ (africa) to human populations
old world
monkeys
What does SIV stand for? Where does it come from?
SIV = Simian Immunodeficiency Virus
-> comes from monkeys
Name the different strains of human HIV
Which is the most deadly? Name some important info about them
HIV-1 = MOST PATHOGENIC/DEADLY
- Related to SIV in gorillas and chimpanzes
- 99% of cases WW
HIV-2
- endemic to West Africa
- Lower mortality rate than HIV-1
Where is HIV/AIDs most prevalent in the world?
Africa
