ENTO 210 1st EditionFinal Exam Study Guide Lectures: 17 - 24Lectures 17 (Sandflies and Leishmaniasis)Leishmania-a genus of Trypanosomatidea (like Chagas and Sleeping sickness-considered a Neglected Tropical Disease (NTD)-Sandfly is the vector**2nd most important protozoan medically and economically-a few are almost entirely human-very common – 70,000-500,000 deaths annuallyLeishmania life cycle*involves promastigotes and amastigotes- fly bites human and injects promastigotes-promastigotes change to amastigotes inside the macrophages of the human-the amastigotes (in the macrophages) multiply and taken up in a blood meal by the sandfly-they change to promastigotes in the midgut of the sandfly and migrate to the probosciswhere they are injected into another humanLeishmaniasis Transmission-sandfly bites are the most common -it can also pass mother to fetus and through blood transfusionsSandfly(diptera, psychodidae, phlebotominae)-almost 1000 species (about 70 carry human disease)-important genera:-Phlebotomus – old world sand fly-semiarid conditions, seasonal-cutaneous leishmaniasis, visceral leishmaniasis, and mucocutaneousleishmaniasis (which is the rarest)-Lutzomyia – new world sand fly-forest conditions, regularly present-cutaneous leishmaniasis, visceral leishmaniasis, and mucocutaneousleishmaniasis-females usually nocturnal feeders-larvae not commonly found, total life cycle is 30-60 days-some are endophagic-adults are weak flyers and usually stay close to homeCutaneous Leishmaniasis -causes a “pizza-like” lesion, usually scars-90% of cases occur in the Middle East and some of South America-most people get in childhood-scars can cause social issues in some cultures  abandonment, etc(at one point they would infect children in a place not very visible, so they would get it over with and not risk persecution)-maintained in rodents, hyraxes, and dogs-some systemic drugs work, many are expensiveMucocutaneous Leishmaniasis (Espundia)-90% in South America-mostly caused by L. brasiliensis-usually starts with lesion, and then chronic ulcers (can affect nose cartilage)-need systemic drugs and surgeryVisceral Leishmaniasis (black fever)-mostly in Asia, Brazil, and Sudan-can affect bone marrow, liver and spleen-fatal if left untreated! (often victim to other diseases)-old world vectors: L. donovani, L. infantum-new world vectors: L. chagasi-lesionswelling, feverinfections-maintained in dogs-need systemic drugsControl-IRS-treated bed nets-control the reservoirsWar-has had great affect in the sudan civil war (largely because of the malnourished people)-risk for American soldiersLecture 18 (Ticks)Ticks-Cheliceriforms, Arachnida, Acari-large, have a toothed hypostome2 major families:Argasidae: soft ticks, have 8 legsIxodidae: hard ticks, have scutum and 8 legs-it’s important to note that the larvae have 6 legsArgasidae-over 180 species-females blood feed more than males, lay several eggs after each mealfound in burrows and nests-medical issues:-tick paralysis (more so in hard ticks)-neurotoxin, can cause death-tick-born relapsing fever-Borellia-found everywhere but Australia and New Zealand-can last 2-9 days and recurs regularly-can live up to 7 years, able to withstand long-term starvationIxodidae-over 700 species-temperate climates-stay on host for up to 4 weeks, then drops and hides-female lays thousands of eggs and dies-larvae and nymph prefer small animals-males usually mate with female on host-Questing – ticks wait for CO2 increase as sign of host*review the differences between soft and hard ticksLyme Disease – newly emergent, first identified in 1970s-most widespread vector-borne disease-Borellia burgdorferi (deers are not a reservoir!!)-over 20000 US cases annually-Ixodes scapularis is the main vector on the east coast-frequently on deer (why deer associated with lyme disease)-cases have to be reported to health officials!-Stage 1: Erythema chronicum migrans – bullseye rash (80% frequency)-can also have symptoms that resemble flue-Stage 2: pathogen spreads through blood stream, rash can be all over body-pain in muscles and joints, affects the heart, dizziness-Stage 3: if untreated, can have severe symptoms-chronic neurological symptoms are possible (like encephalomyelitis)-lyme arthritis**It’s important to note there is no correlation with poverty level**-treatment:antibiotics must be used early-it’s important to remove ticks early!, reduce the primary hosts, treat deer with tickkilling substancesLecture 19 (Lice)-Phthiraptera-Mallophaga (chewing lice) – about 3000 species, feed on hair-Anoplura (sucking lice) – feed on blood, **higher fecundity (reproductive rate)**-about 500 species**high host speciation-most affect rodents, 3 species affect humans-body louse, head louse, pubic louseHuman lice-both sexes feed 3-6 times a day-lay several eggs daily-prefer temperate regions-survive 2-4 weeksBody louse-pediculosis  infestation with lice-can have 100s at once-common in areas with poor hygiene (jails, refugee camps, etc)-Vagabond’s disease – long term exposure, skin can change texture and color, can also affectbehaviorHead louse-nits cement onto hair-little medical significance-more common among childrenPubic Lice-aka crabs-found in course body hair-spread through sexual contact most frequently-no serious medical significanceControl-hygiene makes a huge difference!-shave hair-treat with insecticidesDiseases-Trench fever – Bartonella quintana-non-fatal-transmitted through lice feces – infection by inhalation-big during World war 1-5 day relapsing fever, headache, pain, can cause heart failure (rare)-Louse borne relapsing fever – Borellia recurrentis-bacteria enters people through cuts, scrapes-Central and East Africa (most in Sudan and Ethiopia)-high fever, cough, weight loss-up to 40% fatality if untreated-Epidemic Typhus – Rickettsia prowazeki-obligate intracellular parasite, kills lice-bacteria enter humans through skin cuts and inhalation-fever, rash (50% frequency), pain, heart failure-up to 40% fatality (children don’t normally die)**humans are reservoir-common in wars, camps, jails (Anne frank was a victim)Control-hygiene helps a lot!-insecticides – treat clothes and beds-antibiotics help-vaccine no longer used in US**potential for biological weapon**Lecture 20 (Fleas)-Siphonaptera-about 95% of species feed on mammals-have specialized hind legs for jumping-evolved from winged insects, wingless now-life cycle varies from