Microbiology Exam 2 – Flashcards
Unlock all answers in this set
Unlock answersquestion
| bacteriuria |
answer
| the presence of bacteria in the urine |
question
| dysuria |
answer
| difficult, painful, urgent urination |
question
| pyuria |
answer
| the presence of puss in the urine |
question
| hematuria |
answer
| the presence of blood in the urine |
question
| proteinuria |
answer
| the presence of protein in the urine |
question
| E. coli |
answer
| the majority of urinary tract infections are caused by ( ) |
question
| nongonococcal urethritis |
answer
| refers to any inflammation of the urethra not caused by Neisseria gonorrhoeae (bacterial STD pathogen) signs: urethral itching, dysuria, mucoid urethral discharge |
question
| E. coli Chlamydia trachomatis - bacterial STD pathogen Mycoplasma genitalium - no cell wall (no gram staining), aerobic bacillus MEC |
answer
| causes of nongonococcal urethritis |
question
| cystitis (bladder inflammation) |
answer
| signs: dysuria, pyuria effects more females than males (8:1) |
question
| usually caused by E. coli #2 cause is staphylococcus saprophyticus - facultative anaerobe, gram positive coccus in irregular clusters, typical endogenous bacterium, found naturally on skin and in the genito/urinal area. |
answer
| causes of cystitis |
question
| pyelonephritis |
answer
| in 1/4 of untreated cystitis cases it progresses to the kidneys (in an ascending UTI). signs: dysuria, back pain, hematuia, fever, bacteriuria, inflammation of one or both kidneys tubular destruction, abscess formation, neutrophils (produce enzymes that cause further damage), debri (makes it harder for the kidneys to filter) |
question
| E. coli Mycoplasma hominis - no cell wall, aerobic bacillus, more common in sexually active people, not endogenous, but common in human beings. |
answer
| main causes of pyelonephritis |
question
| glomerulonephritis |
answer
| signs: proteinuria, hematuria due to swollen glomeruli; immune complexes containing streptococcal antigens toxins will be released by the bacterium and the body will respond by producing antibodies - basement membrane becomes obscured due to antigen/antibody complexes, causes lack of filtration and increased BP increased cytokine production - causes inflammation (also effects filtration of BP) |
question
| Streptococcus pyogenes toxins |
answer
| what usually causes glomerulonephritis? |
question
| Treponema pallidum anaerobic spirochete cannot gram stain highly sensitive to environmental stress endoflagella - has a membrane on the outside and just underneath is the flagella. whips around inside and moves in a circular path. |
answer
| pathogen that causes syphilis |
question
| syphilis more fatal than gonorrhea |
answer
| often coexists with gonorrhea bacterium primary stage: chancres, Treponema pallidum comes in contact with skin and burrows in b/c it is anaerobic, 2-4 weeks after the infection secondary stage: hand/feet rash, body rash, condylomata lata (large oozing growths), fever, malaise, lethargy, hair loss, nausea, dissemination of spirochete latent stage: no symptoms, usually not infectious but can be, just stops at the secondary phase. months to years after infection. dangerous when the person is pregnant especially if they are infectious at this time. tertiary stage: gummas on internal organs and skin (abscess, ulcerated area), CV and CNS involvement. |
question
| Neisseria gonorrhoeae gram negative aerobic diplococcus intracellular bacterium - strong survival mechanism fragile |
answer
| pathogen that causes gonorrhea |
question
| gonorrhea |
answer
| invades urethra (urethritis), pus, dysuria, females often asymptomatic GU, endocarditis, meningitis, arthritis, anal and pharyngeal discharge can cause sterility: orchitis in males (inflammation of the testes), salpingitis in females (inflammation of the fallopian tubes) |
question
| Chlamydia trachomatis gram negative aerobic bacillus intracellular resistant to stress - if it is off the human host it can survive |
answer
| pathogen that causes chlamydia |
question
| chlamydia |
answer
| similar to gonorrhea but causes NGU causes an increased risk of cervical cancer in women #1 STD in the US, #1 cause of infertility causes sterility through: orchitis in males (inflammation of the testes) or salpingitis in females (inflammation of the fallopian tubes) discharge is clear mucous, females often asymptomatic most common bacterial STD |
question
| pelvic inflammatory disease |
answer
| any extensive bacterial infection of the female pelvic organs (ovaries, cervix, uterus, oviducts) during reproductive years, 1/10 suffer this and 1/4 will have chronic pain and infertility. |
question
| Papovaviridae |
answer
| the pathogen that causes human pailloma virus infection (genital warts) |
question
| human papilloma virus (gennital warts) |
answer
| condylomata acuminata, pea or cauliflower-like growths; dry, painless growths can lead to cervical cancer and cancer of the penis most common viral STD |
question
| Herpesviridae |
answer
| pathogen that causes herpes simplex virus II infection |
question
| herpes simplex virus II |
answer
| resides in nerve cells painful blisters recurring bouts congenital herpes |
question
| Hepadnaviridae |
answer
| pathogen that causes hepatitis B virus infection |
question
| hepatitis B Virus infection |
answer
| transmitted sexually but also through needles asymptomatic to flu-like symptoms to enlarged liver (liver cancer) |
question
| Retroviridae |
answer
| pathogen that causes human immunodeficiency virus |
question
| human immunodeficiency virus |
answer
| retrovirus - starts with RNA and is converted to DNA, reverse transcriptase binds to monocytes, macrophages, and CD4 receptors on helper T cells symptoms - immune compromised so get other opportunistic infections like pneumonia, thrush (fungal infection of the mouth) |
question
| Trichomonas vaginalis anaerobic protozoan |
answer
| pathogen that causes trichomoniasis |
question
| trichomoniasis |
answer
| vulvovaginitis NGU foul discharge (females) most common protozoal STD pelvic inflammatory disease rare b/c it stays in the vaginal area b/c of the pH, does go into the fallopian tubes. has evolved to stay in the urethra of the penis with the high acidity of urine |
question
| pediculosis |
answer
| pubic lice, crabs attach to pubic hair, feed on blood of host, glue eggs to hair cause papules, itch because of saliva |
question
| scabies |
answer
| mites; burrow into skin, tunnel filled with eggs/feces enzymes and saliva can destroy tissues very easy to auto inoculate yourself through scratching |
question
| Candida albicans yeast (fungus) |
answer
| pathogen that causes candidiasis |
question
| candidiasis |
answer
| common in GI and genitourinary tracts NGU, vulvovaginitis, thrush infection through sexual transmission, antibiotics, cancer treatments, pregnancy, douching, anything that disrupts vaginal pH most common fungal STD |
question
| congenital |
answer
| in-urtero, from mother to fetus |
question
| teratogens |
answer
| any agent that causes physical defects in a developing embryo chemicals, viruses |
question
| fetus has separate blood supply mother has antibodies, immune system |
answer
| what maternal factors protect the embryo from infection? |
question
| fetus cannot protect itself b/c their immune system isn't developed don't have well formed spleens, so they cannot protect themselves. |
answer
| what fetal factors inhibit protection against infection? |
question
| congential (in utero) infection: maternal -> placental -> fetal infection perinatal infection: maternal blood; passage down infected birth canal. postnatal infection: milk, blood, saliva, contact [image] |
answer
| 3 routes of infection in embryo/fetus and neonate. ***KNOW THESE FOR THE EXAM*** |
question
| cytomegalovirus (herpesviridae) |
answer
| what pathogen causes congenital CMV? |
question
| congenital CMV |
answer
| if mother is exposed about 40% of fetuses will be infected symptoms: CNS damage, eye abnormalities, retardation, anemia, enlarged liver and spleen, abnormal skin, microcephaly, inflamed retina, ***pizza pie retinopathy*** |
question
| rubella virus, Togaviridae |
answer
| what pathogen causes congenital rubella? |
question
| congenital rubella |
answer
| most serious infections occur during the first trimester low birth weight, brain, eye, and ear problems, heart lesions, diabetes mellitus MMR vaccine prevents |
question
| congenital HIV |
answer
| in developing countries, 1/4 of infants born to mothers with this disease are infected signs: oral thrush, diarrhea, pneumonia, enlarged liver, lymph nodes, and spleen, developmental problems during the last trimester infection rates are very high can get a C-section, or given antiretrovirus medications, should not breastfeed |
question
| congenital syphilis |
answer
| rare in the US due to screening, common in many countries most common during the latent stage. What about primary and secondary stages? most maternal infections during this stage will result in stillbirths. signs: enlarged liver and spleen, abnormal bone, cartilage, and teeth development |
question
| Toxoplasma gondii, protozoan |
answer
| what pathogen causes toxoplasmosis? |
question
| congential toxoplasmosis |
answer
| usually no ill effects except congenitally or if immune compromised adult ingests cysts from contact with cat feces or insufficiently cooked meat (lamb, pork) retardation, enlarged liver and spleen, jaundice, hydrocephaly, convulsions, stillborn |
question
| conjunctivitis: Neisseria gonorrhoeae, Chlamydia trachomatis, and Staphylococcus spp. meningitis/septicemia: E. coli, Streptococcus spp. thrush: Candida albidans scalded skin/baby syndrome: Staphylococcus aureus |
answer
| examples of infections acquired at birth |
question
| [image] know the sclera, cornea, iris, lens, retina, and conjunctiva. |
answer
| anatomy of the eye |
question
| Staphylococcus aureus |
answer
| blephartis an infection of the lid margin causing dead skin and irritants, glands produce too much fluid. blephartis is usually due to what? |
question
| Staphylococcus aureus |
answer
| A sty is an infection of the lid margin that is a raised, puss filled pocket. Glands become plugged. A sty is usually due to what? |
question
| conjunctivitis |
answer
| inflammation of the conjunctiva |
question
| 1) Haemophilus influenzae 2) Staphylococcus aureus 3) Streptococcus pneumoniae 4) Neisseria gonorrhoeae - neonatal gonorrhea ophthalmia; infant is exposed to pathogen while passing through the birth canal; pus, ulceration of the cornea, blindness. 5) Chlamydia trachomatis - Chlamydial conjunctivitis; infant is exposed to pathogen while passing through the birth canal; usually resolves itself but may lead to scarring of cornea (*trachoma*) |
answer
| most common causes of bacterial conjunctivitis. HAVE TO KNOW THESE FOR THE EXAM. |
question
| trachoma |
answer
| scarring of the cornea leading cause of blindness in the world spread by hands, fomites, birth canals, flies long-term abrasion by scars, turned in eyelashes |
question
| infecting the eyes: flies carrying the microorganism land on children's eyes to feed on discharge family contact: women who take care of children also get the infection dirty hands or face cloths also spread the disease |
answer
| how can trachoma be spread? |
question
| 1) adenovirus - associated with upper respiratory infections, common colds 2) paramyxoviruses - measles 3) herpes simplex virus - varicella zoster (chicken pox) |
answer
| most common viral causes of conjunctivitis |
question
| Acanthamoeba spp. causes conjunctivitis and/or keratitis (inflammation of the cornea) amoeba found in fresh water, tap water, hot tubs, soil, contact lens solution |
answer
| common cause of protozoan conjunctivitis |
question
| allergic conjunctivitis |
answer
| causes itching, redness, and excessive tearing in both eyes. your nose may also be stuffy, itchy, and runny. |
question
| bacterial conjunctivitis |
answer
| often spreads to both eyes and causes a heavy discharge, sometimes greenish. Crusting may appear on eyelids. |
question
| viral conjunctivitis |
answer
| usually only effects one eye, which has excessive watering and a light discharge. crusting on eyelids sometimes occurs. |
question
| rubella |
answer
| what disease causes the development of cataracts in utero? |
question
| cytomegalovirus, Toxoplasma gondii |
answer
| what pathogens can cause the development of retinitis in utero? |
question
| Pseudomonas aeruginosa |
answer
| eye drops can be contaminated with what pathogen? |
question
| nerves blood vessels - blood borne invasions take place across the blood-brain and blood-cerebrospinal barriers |
answer
| what is the main route of infection to the brain (protected by the skull) and the spinal cord (protected by the vertebral column)? |
question
| toxins (neurotoxins) can invade the BBB if the infectious load is high bacterium that is intracellular will help it to get through bacterium within a capsule can evade phagocytic destruction body responds via inflammation at the CNS and can cause damage to inflamed tissues trauma to the brain/CNS |
answer
| What are the different ways that the blood brain barrier are invaded? |
question
| Clostridium tetani gram positive bacillus |
answer
| pathogen that causes tetanus bacteria don't invade, but toxins do, anaerobic conditions spores from soil of feces enter a wound; produces a neurotoxin that is carried by the PNS axons (anaerobic conditions); blocks inhibitory spinal synapses, over-activity of motor neurons; muscle rigidity (lockjaw); diaphragm can't relax and causes death |
question
| toxins block the release of acetylcholine at PNS synapses. contraction is inhibited. |
answer
| what is the mechanism of action of botulism caused by Clostridium botulinum? |
question
| meninges |
answer
| membranes covering the brain and spinal cord |
question
| each possess capsules (virulence factors - ability of an infectious agent to cause disease) 1) Haemophilus meningitis: Haemophilus influenzae (gram negative coccobacillus, aerobic), occurs more in children (causes ear infections that can lead to meningitis) 2) Menigococcal meningitis: Neisseria meningitidis (gram negative diplococcus, aerobic), carried asymptomatically by 20% of the population in nasopharynx; occurs more in young adults in close quarters 3) Pneumococcal meningitis: Streptococcus pneumoniae (gram positive diplococcus, facultative anaerobe), in the throats of many Americans; severe; occurs more in infants, older adults, alcoholics; 30-50% of cases |
answer
| three main bacterial causes of bacterial meningitis (more severe but less common than viral meningitis) headache, sore throat, body rash, drowsiness, photophobia, stiff neck, vomiting |
question
| viral meningitis VIRAL IS NOT AS SEVERE AS BACTERIAL MENINGITIS <- KNOW FOR EXAM |
answer
| most common type of meningitis headache, fever, photophobia many causes: HIV, poliovirus, herpes simplex virus, mumps |
question
| Naegleria fowleri, a free living amoeba can be common in stagnant fresh water ponds and lakes inhaled, invades olfactory mucosa, reaches meninges, can be rapidly fatal. |
answer
| What often causes protozoal meningitis? |
question
| Clostridium botulinum |
answer
| bacterium that causes botulism found in spores from canned foods and soil, ingested, gut to blood. toxins block the release of acetylcholine at PNS synapses (GI tract infection) |
question
| encephalitis |
answer
| severe inflammation of the brain usually viral origin usually tick or mosquito borne, but may also result from polio, mumps, rubella, measles, HIV, CMV, HSV, rabies infection sometimes bacterial, protozoan cerebral dysfunction, nausea, fever, seizures occurs more in summer, early fall (mosquitoes are more active during this time) |
question
| rabies virus, Rhabdoviridae |
answer
| causes rabies encephalitis virus can infect all mammals virus replicates at bite, ascends axons to the CNS, spreads, descends down PNS to skin, salivary glands sore throat, fever, pain at wound, headache, muscle spasms, death relatively long incubation period throat becomes paralyzed and body produces a lot of saliva trying to get rid of the virus, causing foaming at the mouth |
question
| arboviral encephalitis |
answer
| arthropod-borne pathogen (mosquito vector) encephalitis common hosts primarily humans, birds, horses, small mammals chills, fever, headache, severe (coma, death) example: St. Louis Encephalitis |
question
| macule |
answer
| flat red lesion local inflammation immune response rash |
question
| papule |
answer
| raised, red lesion more marked inflammation invasion of neighboring tissues |
question
| vesicle |
answer
| small blister microbe invades epithelium fluid filled ex) HSV, varicella zoster virus |
question
| ulcer |
answer
| epithelium ruptures microbe discharged |
question
| folliculitis |
answer
| infection of the hair follicle caused by Staphylcococcus aureus sebaceous glands become clogged |
question
| boil |
answer
| caused by staphylococcus aureus involved deeper layers of the skin, glands, and/or hair follicles becomes encapsulated and walled off from the rest of the body: becomes harder to treat and harder for the immune system to get to it popping will break the capsule and the Staphylococcus aureus may become systemic |
question
| carbuncle |
answer
| caused by Staphylococcus aureus involves more than one follicle and deep tissue hard, round, NOT WALLED OFF |
question
| Staphylococcus aureus exotoxins of Staphylococcus aureus |
answer
| what can cause toxic shock syndromefever, rash, exfoliation of palms, soles can involve multiple organ systems |
question
| Staphylococcus aureus Streptococcus pyrogenes |
answer
| causes impetigo: vesicles (pustules) that become crusted and rupture spread by contact enter skin through abrasion or insect bite |
question
| ischemia gangrene |
answer
| if a wound causes the blood supply to be interrupted, a condition called ( ) occurs and the wound becomes anaerobic. ischemia leads to death of a tissue, also known as necrosis; this can lead to ( ). |
question
| Clostridium perfringens |
answer
| gram positive bacillus, anaerobic causes gangrene: the death of soft tissue resulting from the loss of blood supply toxins move along muscle bundles, killing cells, necrosis of tissue mechanism: substances released from dead/dying cells provide nutrients for bacterium; as they grow, they ferment carbohydrates in tissues producing gases (CO2, H2) causing tissue swelling; bacterial enzymes degrade collagen in the skin. |
question
| Mycobacterium leprae |
answer
| gram positive bacillus, aerobe causes leprosy (Hansen's disease) grows in the PNS and skin prefers outer, cooler portions of the body nerve damage from cell mediated immune response neural form: tingling sensation on the skin where the area of skin is responding to nerve damage. usually a person with a healthy immune system can rid themselves of the neural form (found in the US) progressive form: will die from co-infection from something else, not the leprosy. progressive form is not highly contagious. nodules, disfigurement armadillo is the animal reservoir in the US |
question
| dermatophytes |
answer
| fungi that colonize in the hair, nails, and outer layer of the epidermis degrade keratin present by secreting keratinase |
question
| Tinea capitis |
answer
| ringworm of the scalp, dermatomycoses caused by a dermatophyte |
question
| Tinea cruris |
answer
| jock itch, dermatomycoses caused by a dermatophyte |
question
| Tinea pedis |
answer
| athlete's foot, dermatomycoses caused by a dermatophyte |
question
| Tinea corporis |
answer
| ringworm of the body, dermatomycoses caused by a dermatophyte |
question
| Varicella-Zoster virus shingles and chickenpox are different expressions of the same virus |
answer
| causes chickenpox Herpesviridae entry into the respiratory system, eventually localizes in skin cells vesicle -> rupture -> scab |
question
| Herpes-Zoster virus shingles and chickenpox are different expressions of the same virus |
answer
| causes shingles Herpesviridae latent varicella-zoster virus is in the dorsal root ganglion near spine virus reactivates (induced by stress) [image] a cluster of small bumps turns into blisters as the virus starts to reactivate; reactivation and blisters fill with lymph fluid; crusting over; healing; postherpetic neuralgia can sometimes occur (nerve damage) leading to pain without rash, difficult to manage |
question
| Togaviridae |
answer
| causes rubella, also known as German measles acquired mostly through inhalation of infected droplets may also be present on skin, in urine, and in feces incubation of 2-3 weeks milder than measles, may go undetected rash of small raised spots, fever complications in children rare; may cause adult encephalitis congenital rubella can cause deformities |
question
| Paramyxoviridae |
answer
| causes rubeola (measles) highly contagious, spread by respiratory route ***measles is the leading cause of vaccine preventable disease in the world*** ***Koplik's spots*** (red patches with central white spot) inside mouth; body rash cough, conjunctivitis, fever, lymph node swelling can be complicated by otitis media and pneumonia |
question
| Poxviridae |
answer
| causes molluscum contagiosum skin infection only affecting humans approximately 1 in 6 young infected at some point most commonly seen in 1-10 year olds can affect any area of the skin (body, arms, legs) flesh colored dome-shaped lesions are typical transmitted through contact or shared articles of clothing (can be sexually transmitted in adults, could be mistaken for warts (HPV) generally lasts 6 weeks to 5 months (can last longer, cases reported up to 5 years) |
question
| Trypanosoma cruzi |
answer
| protozoan pathogen that causes the muscle infection Chagas' disease found in central and south america, but entering US vector: kissing bug deposits pathogen on skin when feeding and defecating Romana's sign (swollen eyelid) fever, tissue destruction via autoimmune response invades myofibrils of the heart and CNS |
question
| Trichinella spiralis, roundworm |
answer
| causes the muscle infection, trichinosis encysted form in the muscle of the host ingestion of raw hamburger or pork sausage dangerous fever, GI upset, edema around eyes larva is in cyst in muscle; larva break out of cyst in the SI; larva in mucosa of SI; larva circulate and stay in the diaphragm. most infections are insignificant, only serious if high numbers of larvae are ingested |
question
| osteomyelitis |
answer
| causes: fractures, orthopedic operations, abscessed teeth, UTIs, Staphylococcus aureus from a popped boil often caused by one infection, but may be a mixed infection systemic fungal infections can also cause it |
question
| Borrelia burgdorferia |
answer
| spirochete that doesn't gram stain, microaerophilic causes lyme disease vector: hard (deer) tick main reservoir: mice #1 vector borne disease in the US |
question
| 1) rash, flu-like 2) increased heart rate; Bell's palsy (paralysis of the side of the face); meningitis, encephalitis 3) lyme arthritis (syphilis-like problem) can be reversed up until the 3rd stage, but damage may have been done by this point |
answer
| stages of lyme disease |
question
| want to try to get close to the mouth, if you pull out the body the pathogen will get pushed in. remove it at the angle it is embedded in the body. don't burn it off and don't cover it with nail polish |
answer
| how do you remove an embedded tick? |
question
| Borrelia spp |
answer
| causes relapsing fever: high fever, jaundice, rose-colored skin spots; macular rash spirocete, doesn't gram stain, microaerophilic vector: soft tick main reservoir: mice transovarian transmission - pathogen is in the tick eggs; a female pregnant tick will pass the pathogen to the host through the egg 3 or 4 relapses may occur, each shorter and less severe. why? the body develops memory cells and specific antibodies, however the pathogen evades some phagocytosis by immune cells and changes cell surface antigens |
question
| Rickettsia rickettsii |
answer
| causes rocky mountain spotted fever gram negative, intracellular aerobic bacillus vector: hard (dog) tick transovarian transmission mainly in SE US intracellular in the host (endothelium) AND the vector (RBCs), very lethal pathogen damages the permeability of endothelium of blood capillaries by replicating in them; abrupt onset, fever, headache, chills, macular rash, loss of plasma, shock, often fatal if misdiagnosed [image] |
question
| Ehrlichia chaffeensis |
answer
| causes ehrlichiosis vector: hard (dog) tick gram negative, intracellular aerobic bacillus mainly SE and SC US chills, fever, headache, muscle aches, nausea, maculopapular rash (in less than 1/2 of cases), malaise |
question
| Rickettsia prowazekii |
answer
| causes epidemic typhus gram negative intracellular aerobic bacillus vector: human body louse multiply in the gut epithelium of the louse, secreted when feeding on skin; pathogen enters the skin through scratch; spread to vascular endothelium in skin, heart, muscle, CNS, etc. fever, chills, macular rash, meningoencephalitis, high mortality africa, central/south america, US |
question
| flavivirus, Flaviviridae |
answer
| causes arbovirus encephalitis (west nile virus, St. Louis encephalitis) vector: mosquitoes vertebrate reservoir: birds 10 types worldwide, 6 in US; common in US most cases subclinical, some fatal; all active cases characterized by chills, headache, fever; if progresses, mental confusion, coma, neurological problems SLE most common; both SLE and WNV are throughout US; WNV more severe; fatality increases with age (both) |
question
| flavivirus, Flaviviridae |
answer
| causes viral hemorrhagic fever (yellow fever) vector: mosquito fever, chills, headache; then vomiting, nausea; then yellowing of the skin (jaundice) mortality rates high (~20%) was endemic to US until mosquito control programs. the vector that carries this pathogen is very common in the US so the pathogen can be spread in the US. currently in central america, SA, africa |
question
| flavivirus, Flaviviridae |
answer
| causes Dengue fever (viral hemorrhagic fever) vector: mosquito similar to yellow fever but milder; fever, body rash, muscle and joint pain; rarely fatal but hemorrhagic fever shock syndrome is more common in children endemic to caribbean area (mostly), but also india, SE asia, pacific areas |
question
| Plasmodium spp. there are 4 different variations in the human host (4 different stages of life) there are 4 different pathogen species |
answer
| protozoan that causes malaria vector: mosquito 4 FORMS OF THE DISEASE characterized by chills, fever, headache during 2-3 day intervals; some forms benign (lethargy) to severe (destruction of RBCs/death) life cycle: with the release of merozoites (immature stage), there is also the release of toxic compounds that cause recurring symptoms immature stage is injected into the blood stream, infects liver and matures, released into the blood, picked up by another mosquito and can infect other humans people who survive acquire limited immunity |
question
| there are many different variations (different cell surface antigens) and there are different stages intracellular pathogen changing cell surface antigens the release of toxic compounds |
answer
| why is it so hard to develop a vaccine for malaria? |
question
| Schistosomiasis |
answer
| vector: snail pathogen: fluke (trematode) helminth is 20 mm long. female lives in groove in male. continual supply of eggs. eggs lodge in tissue, cause ganulomas (egg mass). most areas of the US the suitable snail vector not present. so, 400,000 immigrants may be shedding eggs, but the lack of snail vector and proper sanitation prevents epidemic. typically, the eggs are secreted in feces into water, has to be on a certain snail to mature to the next stage. penetrates the skin and becomes systemic via CV system. eventually goes to the liver and from the liver migrates to the intestines or to the bladder depending on species. 1 causes cystitis, 2 cause enteritis adult worm can evade host immune system by coating with a layer that mimics host tissue |
question
| helminth disorder - IgE help fight parasitic infections!!! KNOW THIS FOR EXAM eosinophils spike in a parasitic (and more specifically a helminth) infection |
answer
| what immune system cells/products would help in the case of Schistosomiasis? |
question
| animal diseases non-human vertebrate host is the principle reservoir host; humans involved secondarily rarely human to human infection |
answer
| what are zoonoses? |
question
| we are in contact with the definitive host pathogens can evolve to infect humans as primary reservoirs biological warfare |
answer
| why should zoonoses be studied? |
question
| Brucella spp |
answer
| causes brucellosis (undulant fever) gram negative, aerobic coccobacillus, small intracellular pathogen Category B 3 species pathogenic to humans patients frequently present with fever of unknown origin, mild to severe in humans 2 species are mild in humans, and one is severe in humans [image] invades macrophages and impairs ability to phagocytize. |
question
| Francisella tularensis |
answer
| causes tularemia (rabbit fever) gram-negative aerobic coccobacillus; capsule inhibits phagocytosis category A transmitted to humans via contact with rabbits, muskrats, ground squirrels, tick bites, deer flies, undercooked meat ulcer at site of infection; lymph node swelling -> can become systemic via lymphatic system most cases due to rabbit contact if animal-infected dust inhaled, can lead to pneumonia small infective dose needed; fatality 100% if untreated |
question
| Bacillus anthracis |
answer
| causes anthrax gram positive facultative anaerobic bacillus endospore forming; natural soil-dwelling organism category A endospores taken up by macrophages (becomes intracellular); two exotoxins (edema and lethal toxins) edema toxin: causes edema of the body and impairs the ability of the macrophages to phagocytize lethal toxin: causes the macrophages to die (and this causes the release of more bacteria into the blood stream) strikes mainly grazing animals people at risk: handlers of animals, hides, and wool |
question
| 1) cutaneous: most common, least fatal; 20% fatality if untreated 2) gastrointestinal: from eating undercooked meat, 50% fatality if untreated 3) inhalation/pulmonary: breathed in, (Woolsorter's disease); most serious; 100% fatal if untreated |
answer
| three forms of anthrax |
question
| Yersinia pestis |
answer
| causes the plague (black death) gram positive bacillus, facultative anaerobe; virulent anti-phagocytic capsule category A vector: fleas rodent reservoirs: rat (primary disease reservoir), squirrels, ground sqirrels, prairie dogs, mice causes blood clot in the gut of fleas that blocks lumen and causes the flea to regurgitate the pathogen to the next host rodents sicken, vector leaves reservoir, finds human |
question
| bubonic plague: flea bite -> blood and lymph -> proliferate in phagocytic cells -> fever, enlarged lymph nodes (buboes); 50-75% fatality if untreated; no person to person spread septicemic plague: inhalation -> high numbers in blood (septic shock) pneumonic plague: Yersinia pestis in lungs; airborne droplets, 100% fatality if untreated; rapid person to person spread [image] |
answer
| 3 types of plague |
question
| plague |
answer
| pandemic occurrences of ( ) have been directly responsible for more human deaths than any other infectious disease except for tuberculosis and malaria. |
question
| Leptospira interrogans |
answer
| causes leptospirosis aerobic spirochete, doesn't gram stain infected animals (dogs, cats, rats, horses) shed the bacteria in urine for extended periods human contact with urine contaminated water, soil; pathogens enter abrasions or ingestion fever, chills, headaches, aches (episodic) usually not fatal, kidney failure most common cause of death 50 cases reported per year in US, worldwide; very undiagnosed |
question
| Chlamydophila psittaci |
answer
| causes psittacosis (ornithosis) gram negative, obligate aerobe, intracellular bacillus natural reservoir - any bird species (feces) bacterium resistant to stress, transmitted via air (inhalation of droppings) subclinical to fever, headache, chills, delirium (NS involvement), atypical pneumonia pet store owners, turkey farmers at risk 100 cases/year in US; 20% fatality if untreated has a metabolically inactive, infectious form and a metabolically active, non-infectious form |
question
| 1) palpebral conjunctiva: covers the posterior surface of the eyelids 2) bulbar conjunctiva: coats the anterior portion of the eyeball 3) fornix: the transition portion, forming the junction between the posterior eyelid and the eyeball [image] |
answer
| 3 sections of the conjunctiva |
