Exam 6 LAST ONE! Flashcards
(127 cards)
1
Q
State the major risks factors for developing an STD.
A
- number of sexual partners
- age of onset of sexual activity
- injection drug use
2
Q
Define the term coinfection
A
transmission of more than 1 pathogen at the same time
if you have gonorrhea you will probably be infected with chlamydia
3
Q
local infection
A
affects one body part or organ
4
Q
systemic infection
A
bloodstream
5
Q
define the term pelvic inflammatory disease
A
Extensive bacterial infection of the female pelvic organs
6
Q
which conditions can lead to PID
A
undiagnosed, subclinical, or recurrent infections
7
Q
symptomatic infection
A
the infected person does exhibit apparent symptoms of an infection
8
Q
asymptomatic infection
A
can remain undetected for a long time
9
Q
What are the reproductive tract bacterias?
A
- Chlamydia trachomatis
- Neisseria gonorrhea
- Treponema pallidum
- Haemophilus ducreyi
- Streptococcus agalacticae
10
Q
what is the gram stain for Chlamydia trachomatis?
A
gram (-) rods
11
Q
what is the gram stain of Neisseria gonorrhea?
A
gram (-) diplococci
12
Q
what is the gram stain of Treponema pallidum?
A
Gram-negative spirochete
13
Q
what is the gram stain of Haemophilus ducreyi ?
A
Gram-negative rods
14
Q
what is the gram stain of Streptococcus agalacticae ?
A
gram-positive cocci
15
Q
What is the virulence factor of Chlamydia trachomatis ?
A
invade and replicate within host epithelial cells using a unique biphasic developmental cycle
16
Q
What is the virulence factor of Neisseria gonorrhea?
A
- Fimbriae: attachment to non-ciliated epithelial
cells of the urethra and cervix - IgA protease: inactivates IgA antibodies
- Outer membrane proteins subject to antigenic change: evades
immune response - Penicillinase enzyme: inactivates penicillins
- Endotoxins
17
Q
What is the virulence factor of Treponema pallidum ?
A
evade the immune system, disseminate throughout the body, and cause chronic infection.
18
Q
What is the virulence factor of Haemophilus ducreyi ?
A
adhere to epithelial cells, evade immune responses, and cause ulcerative lesions.
19
Q
What is the virulence factor of Streptococcus agalact ?
A
colonize mucosal surfaces, evade immune responses, and cause serious infections, especially in newborns, pregnant women, and immunocompromised individuals.
20
Q
There are 15 types of Chlamydia trachomatis, state which types cause blindness, which types are sexually transmitted, and which types tend to be invasive.
A
Blindness: Serovars A, B, Ba, C
sexually transmitted: Serovars D–K
Invasive: Serovars L1, L2, L2a, L2b, L3
21
Q
What is meant by ‘congenital syphilis’?: Treponema pallidum
A
organism transmitted through placenta to fetus
22
Q
Explain the phases in the disease process of syphilis and which phases are contagious
A
T pallidum is released straight into the bloodstream of the fetus, causing spirochetemia
*Early fetal spread to most organs including: - bones, kidneys, spleen, liver, and heart.
*This leads to widespread inflammation throughout these organ systems, resulting in various clinical manifestations.
*Can occur in any phase
*Most common in 2nd and 3rd phase
*Very serious
*Can cause miscarriage/fetal death
*Damage to mental development, teeth, bones, facial deformity, hearing/vision loss, limb/joint problems, rash
- most contagious in 1+2 stage
23
Q
For streptococcus algalactiae, explain what Group B strep indicates?
A
- Group B Strep refers to Streptococcus agalactiae classified by the Lancefield Group B antigen.
- it is part of normal flora but can become opportunistic, especially dangerous for newborns and vulnerable individuals.
24
Q
What does beta indicate ?
A
Complete lysis of red blood cells, clear zone
25
Streptococcus algalactiae can be normal flora for the woman. Explain why it can be very dangerous if the newborn acquires it during the birthing process.
- newborn vulnerability and the invasive potential of GBS.
- life threatening blood stream pneumonia
26
name 4 important pieces of info about Mycoplasma/Ureaplasma
- Can be normal flora of the urogenital tract
- Mycoplasma: in men and women: urethritis
- Ureaplasma: can be a factor in infertility
- Both of these organisms can cause problems for pregnant women
27
What are the reproductive tract viruses?
- Herpes Simplex Type 2
- Human Papillomavirus (HPV),
- HIV
- Hepatitis B
28
Of the reproductive viruses which are RNA and DNA?
- Herpes Simplex Type 2: DNA
- Human Papillomavirus (HPV): DNA
- HIV: RNA
- Hepatitis B: DNA
29
Important information about Herpes Simplex Virus (HHV-2)
- Primary lesions: painful blisters
- Virus remains latent in nerves at the base of the spine
- Recurrence are possible: tend to decrease in severity and number over time
- Can be serious if transmitted from mother to baby
30
There are >150 types of Human Papillomavirus (HPV) true or false?
true, 40 are anogenital types that can be sexually transmitted
31
important information about HPV
- Productive infection: warts; most common types 6 and 11
- Non-productive infection : no warts but a higher frequency of leading to transformation and cancer over time; most common types 16 and 18
32
How can high-risk types of HPV lead to cancer?
It can lead to transformation of the infected cells, malignancies, cervical cancer
33
what is the transmission rates of HPV?
75-100%
34
What are the vaccine of HPV?
surface proteins of the 9 most common types
35
Human Immunodeficiency Virus (HIV), HIV causes aids what does AIDS stand for?
acquired immune deficiency syndrome
36
HIV-1 is the most common worldwide, true or false?
True
37
What cell type does HIV infect? Why are these cells so important to the body?
CD4 Cells. they are important to the body because they are critical to the bodies immune response
38
Describe the disease process of HIV
1. Viral spikes binds to CD4 markers + a coreceptor
*Receptors found: TH lymphocytes, dendritic cells, macrophages, monocytes, B lymphocytes
*CD4 cells are critical to the body’s immune response
2. Penetration of virion into host cell
*Membrane fusion
3. Uncoating of viral capsid
** Viral ssRNA converted to ds DNA by viral
enzyme: reverse transcriptase
4. Integration of viral DNA into host cell DNA
5. Biosynthesis: replication of viral nucleic acid; transcription and translation of viral proteins and enzymes
6. Assembly of viral particles (cytoplasm)
7. Release of virions
*Budding
39
Explain the difference between an ‘active’ infection and a ‘latent’ infection
Active:
The pathogen (virus, bacteria, etc.) is actively replicating in the host, Symptoms are usually present (e.g., fever, rash, pain), The immune system is responding, and the infection may be contagious.
Latent:
The pathogen is present in the body but is in a dormant (inactive) state, No symptoms are present, The organism is not actively replicating, but it can reactivate later, often triggered by stress, illness, or immune suppression.
40
How is HIV diagnosed?
CD4 cell count <200/ml of blood (normal: >500/ml)
41
How is HIV treated?
1. entry or fusion inhibitors
2. HIV reverse transcriptase inhibitors
3. integrase inhibitors
4. protease inhibitors
42
What are the list of bacteria under skin pathogen?
Staphylococcus aureus
Streptococcus pyogenes
Pseudomonas aeruginosa
Leptospira interrogans
Clostridium tetani
Clostridium perfringens
43
what is the gram stain for Staphylococcus aureus
Gram (+) cocci
44
what is the gram stain for Streptococcus pyogenes
Gram (+) cocci
45
what is the gram stain of Pseudomonas aeruginosa?
Gram (-) rod
46
what is the gram stain of Leptospira interrogans?
gram negative spirochete
47
what is the gram stain of Clostridium tetani "lockjaw" ?
Gram (+) rod: spore-forming; anaerobic
48
what is the gram stain of Clostridium perfringens?
Gram (+) rod; ; spore forming; anaerobic
49
The catalase test for Staphylococcus aureus is positive and its beta hemolytic, true or false?
true
50
The catalase test for Streptococcus pyogenes is negative and its beta hemolytic, true or false?
true
51
What is the only species of Staph that produces coagulase. What reaction does this enzyme catalyze?
Staph aureus, Fibrinogen → Fibrin (clot)
52
what is the Most common infection through the skin: infection of the hair follicle?
Staphylococcus aureus
53
what diseases can streptococcus pyogenes cause ?
- impetigo
- erysipelas
- necrotizing fasciitis
54
disease process of impetigo
*Spread by contact
*Bacteria penetrate skin through
minor abrasions/ insect bites
*Produces superficial vesicles w/ thin amber crusts
*Most often found around mouth, face, extremities
*Infectious until 24 hours after starting antibiotics
*More common: in young children; summer months
55
disease process of erysipelas
Acute infection of dermis
*More common: 2-6 year olds ; >60 years
*Often preceded by:
*Strep sore throat, high fever
*Cuts or breaks in the skin; may start as local tender lesion
*Shiny red, edematous lesions of face (20%) and legs (80%)
*Fever, shaking, chills
*Can lead to: tissue necrosis, septicemia, shock
56
disease process of necrotizing fasciitis
Rapid spreading deep infection (up to inch/hr)
*Mortality rate: 20% even with treatment
*Caused by ‘flesh-eating’ strains
*Bacteria kills off cells of fascia
*Layers of fibrous tissue beneath the skin
(including nerves and blood vessels)
*Overlying tissue is deprived of blood flow and dies
*Red, warm, swollen skin, severe pain, fever
*Toxins and enzymes may become systemic
- severe scarring
- loss of limb
- sepsis, shock, organ failure
57
what is the treatment of of necrotizing fasciitis?
removal of all tissue to the bone
58
Which test is done for Pseudomonas aeruginosa and what are the results?
Oxidase test, positive
59
Is Pseudomonas aeruginosa an opportunistic organism and resistant?
Yes
60
How does the toxin for Clostridium tetani work?
- Produce potent exotoxin called “tetanospasmin”
Lethal neurotoxin (CNS)
- Toxin inhibits the release of neurotransmitters responsible for the relaxation of muscles
- Result: constant contraction of voluntary muscles
”lockjaw” : spasms of neck and jaw appear early
painful; can break bones
61
how does the toxin for Clostridium perfringens work?
Toxins: at least 16 identified “lethal toxins”
62
What is an anti-toxin and why is this a useful treatment?
an antibody with the ability to neutralize a specific toxin and because it neutralizes toxins produced by harmful bacteria, helping to prevent or treat toxin-mediated diseases
63
what is mycoses
fungal infections that affect humans or animals
64
Explain ‘cutaneous mycoses
Cutaneous mycoses are fungal infections that affect the outer layers of skin, hair, and nails, caused by dermatophytes. They are often contagious and present with itchy, scaly, or ring-shaped rashes (e.g., ringworm, athlete’s foot).
65
Explain subcutaneous mycoses
Subcutaneous mycoses are deeper infections involving the dermis and subcutaneous tissues, caused by fungi from the environment (e.g., soil or plants) that enter through skin injuries. These are not contagious and usually lead to chronic nodules or ulcers at the site of entry (e.g., sporotrichosis).
66
what is dermatophyte ?
fungi that colonizes hair skin and nails
67
what are the 3 genera of dermatophytes?
- Trichophyton
- Microsporum
- Epidermophyton
68
what does dermatophytes use for growth ?
keratin
69
How are dermatophytes diagnosed ?
microscopic evaluation and by culture
70
What causes Subcutaneous mycoses?
Sporothrix schenkii
71
Eye Pathogen: Ophthalmia neonatorum
Pus-forming conjunctivitis of the newborn
72
What causes Ophthalmia neonatorum? what is prevention?
- Neisseria gonorrhea and Chlamydia trachomatis.
- prevention is antibiotics
73
What is Bacterial conjunctivitis caused by ?
- Staph aureus
- Strep pneumonia
- Neisseria gonorrhea
- Pseudomonas
- Haemophilus influenza
74
What is Trachoma?
- Leading cause of blindness worldwide
- Grows in conjunctival cells of the eye
75
Herpes can also be an eye pathogen: read these fun facts
- the virus travels into the ophthalmic nerve rather than the mandibular branch
- Leading cause of blindness in the U.S.
76
What does the adenovirus cause ?
- epidemic keratoconjunctivitis
- "shipyard" eye
77
What does Enterovirus70 and Coxsackie Virus A24 cause ?
- acute hemorrhagic conjunctivitis
- More common in warm/humid climates and in crowded areas with poor hygiene
78
What are zoonoses ?
disease that occur primarily in wild and domestic animals and can be transmitted to humans
79
Discuss the difference between a ‘direct zoonoses’ and an ‘indirect zoonoses’.
Direct: direct contact with animals like handling them, their products or bites.
Indirect: pathogen transmitted from the animal population to the human population through insects
80
What are direct zoonoses ?
- Bacillus anthracis
- Brucella abortus
- Bartonella henselae
- Leptospira interrogans
81
List the gram stains for Bacillus anthracis, Brucella abortus, Bartonella henselae
Bacillus anthracis: Gram (+) rod; spore former
Brucella abortus: Gram (-) coccobacilli
Bartonella henselae: Gram (-) rod
Leptospira interrogans: Spirochete ; ~ 200 types
82
what are the three forms of bacillus anthracis ?
* Cutaneous (most common)
* Gastric
* Pulmonary
83
what is the virulence factor of Bacillus anthracis?
1. Capsule (encapsulated strains cause anthrax)
2. Production of enzymes and toxins
Both encoded on plasmids
Effect: edema, trigger massive inflammation/shock; evade immune response; destroy tissue; (lethal)
84
How is anthrax prevented?
- Animal vaccine: live attenuated non-encapsulated strain
- Human vaccine: purified protein; can be given to people with occupational contact with livestock or products (hides/bones) or military personnel
- Carcasses of contaminated animals burned or chemically decontaminated
- Imported items (e.g. animal hides, hair, bones) gas sterilized
85
How is anthrax treated?
- Anti- anthrax serum
- penicillian, sulfonamides, broad spectrum antibiotics
86
what are 3 important facts about brucella abortus?
- Brucella abortus most common species in the U.S.
- Reservoir: cattle
- Vaccine: live attenuated bacteria
87
What is the source of Bartonella henselae?
Kittens/Cats
88
What is Leptospira interrogans and its transmission?
- Parasite in wild and domestic animals (not humans)
- Transmission: contact with urine of an infected animal
89
Is rabies RNA or DNA ?
RNA
89
Is hantavirus RNA or DNA
RNA
90
Is Ebola Virus and Marburg Virus RNA or DNA?
RNA
91
Lassa Fever RNA or DNA ?
RNA Virus
92
Rabies infects the CNS, true or false?
True
93
How is rabies prevented? How is rabies treated? What is the vaccine of rabies
1.
- Vaccination of domestic animals
- Elimination of strays
- Strict quarantine practice
2.
- Injection of human rabies
- antiserum
3.
- vaccine: 1,3,7 and 14 days post exposure
94
What is the source of Hantavirus?
- inhalation of virus from infected rodent excrements
- Can rapidly progress to respiratory failure
95
What is the source of Lassa Fever ?
- Found primarily in West Africa
- Source: rats endemic to sub-Saharan Africa
96
What are the indirect zoonoses?
- Yersinia pestis
- Francisella tularensis
- Borrelia burgdorferi
- Rickettsial diseases
97
What are the gram stains of
- Yersinia pestis
- Francisella tularensis
- Borrelia burgdorferi
- Rickettsial diseases
Gram (-) rods;
- Borrelia burgdorferi (spirochete) and Rickettsial diseases (obligate intracellular) are gram negative
98
what plague does Yersinia Pestis cause?
Bubonic Plague
99
Explain the difference between ‘bubonic’ , septicemic and ‘pneumonic’ plague.
septicemic: infection spreads to blood stream
bubonic: bite of flea, most common on legs
pneumonic: untreated bubonic or septicemic which spread to lungs, inhaling droplets containing the bacteria
100
What are the sources of Francisella tularensis?
Rabbits
101
What does Borrelia burgdorferi ?
- Lyme disease; most frequent vector-borne disease in U.S.
- Long term complications include cardiac, joint and neurological problems
102
What are the preventive measures against lyme disease?
- avoid tick habitats
- reduce tick population
- personal protection
- check for and remove ticks ASAP
103
Rickettsia is an ‘unusual’ prokaryote. Review the unusual features of this organism.
tiny, intracellular, poorly stained by Gram methods, transmitted by vectors, and highly dependent on its host for survival and energy.
104
Rickettsia needs arthropod vectors: vectors does NOT vary depending on Rickettsial species. true or false?
False, they do vary depending on rickettsial species
105
What kind of cells does obligate intracellular parasites like rickettsia infect?
endothelial
106
What Rickettsia species are involved in human disease?
- Rickettsia rickettsii: Rocky Mountain Spotted Fever
- Rickettsia prowazekii: Epidemic Typhus
- Rickettsia typhi: Endemic Typhus
107
Explain why a spotted rash is a hallmark of Rickettsial diseases.
Rickettsia bacteria infect and damage endothelial cells, which line the small blood vessels (capillaries) leading to vasculitis, or inflammation of the blood vessels
108
Name the 2 major groups of protozoa that can be carried by insect vectors to cause human disease.
hemoflagellates and sporozoa
109
What are hemoflaggellates?
long, slender flagellated protozoa
110
what are the two genera of hemoflaggellates?
- Trypanosoma
- Leishmania
111
What is important info about Trypanosoma?
There are 2 types:
Trypanosoma brucei:
- carried by the tsetse fly
- Africa
- Causes African Sleeping Sickness
Trypanosoma cruzi
- carried by the reduvid bug
- Central/South America
- Causes Chagas Disease
112
What carries Leishmania ? Where is it found? what does it cause?
sandfly, tropical areas of the world, cutaneous or visceral disease depending on which species of Leishmania infected with
113
What is sporozoa?
non-motile protozoa
114
What are the major genera of sporozoa?
- Plasmodium
- Babesia microti
115
how is plasmodium carried?
female Anopheles mosquito
116
How does plasmodium cause malaria?
1. transmission
2. liver stage
3. blood stage
4. blood stage
5. gametocyte formation
6. mosquito stage
117
How is malaria prevented and treated?
mosquito control
- Protective clothing
- Insect repellents (DEET)
- Window screens/ mosquito nets
- Remaining indoors at night
- Elimination of all stagnant pools of water
118
What are the 5 non motile species of plasmodium?
P. malariae
P. vivax
P. falciparum (most virulent)
P. ovale
P. knowlesi
119
How is Babesia Microti carried ?
Ixodes scapularis tick
120
List the 2 major families of viruses that have species which can be carried by insect vectors to cause human disease.
Togaviridae and Bunyaviridae
121
Arboviral encephalitis: what is encephalitis?
virus transmitted by insect vectors
122
what is the common insect vector ?
mosquito
123
What viruses can cause arboviral encephalitis?
- west nile virus
o Reservoir: birds
o First identified in U.S. in 1999
- LaCrosse Virus
o Eastern U.S. and Texas
o Reservoir: small mammals (e.g. squirrels and chipmunks)
- Jamestown Canyon Virus
o Upper Mid-West (late spring-early fall)
o Reservoir: deer and mice
124
What is Viral Hemorrhagic Fever?
- Causes extreme fever and internal bleeding
125
what is the vector of Viral Hemorrhagic Fever
Aedes mosquito
126
what viruses can cause Viral Hemorrhagic Fever ?
* Dengue Virus
* Chikungunya Virus
* Yellow Fever Virus
* Zika Virus
