micro D2

septic tanks

septic tanks

used by homes that aren’t part of a larger sewage treatment system

anaerobic

sludge digestion is collected in ……. sludge digesters

landfills

stabilized sludge is disposed of in

primary treatment

sewage treatment: physical removal of large solids, grinding, screening, large stuff settles (sludge), removes about 1/3 of the biologically degradable material

biochemical oxygen demand

the amount of dissolved oxygen that must be present in water in order for microorganisms to decompose the organic matter in the water, used as a measure of the degree of pollution.

secondary treatment

sewage treatment: biological step, bacteria aerobically consume most of the remaining BOD, starter cultures of activated sludge are used to start new tanks

disinfection and release

if released into a water supply, chlorination only. If reused as drinking water, additional steps like membrane filtration and ozone treatment

tertiary treatment

additional removal of BOD in mad-made lagoons or wetlands

sewage

wastewater from inside or around homes

eutrophication

too many nutrients (algal blooms)

coliforms

gram negative, facultative anaerobic rods that can ferment lactose with gas formation within 48 hours

fecal coliforms

coliforms that are residents of the intestinal tracts of mammals

indicator organism

to test for contamination by fecal waste use an

san filtration

particulate matter sticks to the sand grains, some use activated charcoal to remove chemicals, some use bacteria to catch particles in biofilms, inexpensive and easy to maintain

membrane filtration

water passed through a membrane with tiny pores, completely removes large organisms like Giardia, relatively expensive, difficult to maintain

chlorine

effective disinfectant against many organisms (not Giardia), inexpensive, leaves residual taste

ozone, reactive oxygen

disinfectant that kills by doing oxidative damage to microogranisms, no residual taste, expensive hard to maintain

UV light

disinfectant that uses tubes to give good UV exposure, no residual taste, expensive hard to maintain

fungi

eukaryotes, 1/3 of antibiotics, bioremediation and biodegradation, herbal medicines

saprotroph

something that feeds on decaying matter

how fungi compete w bacteria

can grow with very little moisture, can eat some things that most bacteria can’t, more resistant to osmotic pressure, produce antibiotics to combat bacteria, use multicellular structures to penetrate food sources

chitin

the cell wall in fungi is made of

fungi

…… have a nucleus while bacteria dont

fungi

…. have chitin walls while animals dont

fungi

….. can’t do photosynthesis while plants can

filamentous

……. growth in fungi uses branches to explore

dimorphic

…….. fungi can switch between yeast and mycelial forms

YM shift

shift between yeast and mycelial forms

fairy circles

filamentous growth in the wild leads to …… …….

spores

almost all fungi can form ….

asexual spores

clone of original (like endospores)

sexual spores

result of sexual reproduction

superficial and cutaneous mycosis

fungal infection of the skin, hair, or fingernails

dermatophytes

fungi that can cause cutaneous mycosis

tinea/ringworm

superficial and cutaneous mycosis can also be called

keratinases

dermatophytes secrete

keratinase

breaks down keratin into a digestible form

-hair and nails and mostly keratin

person to person

superficial and cutaneous mycosis are passed from

anthropophilic

passed person to person

superficial and cutaneous mycosis

itchy rash, often circular, hair loss, blackened fingernails, toenails (eventually fall off)

KOH test

scrape the edge of a lesion, place in KOH, look under the microscope. KOH dissolved fragile human cells, leave touch fungal cell walls intact

antifungal drugs

how to treat superficial and cutaneous mycosis?

sporotrichosis

rose picker’s disease, caused by a fungus that grows on decaying plant matter, usually enters the body through an abrasion

sporotrichosis

red, tender, pus-filled, eventually ulcerous lesions in a line. fungus invades lymphatic vessels and gradually moves along the lymphatic system. infection is not systemic inflammatory.

dimorphic

sporothrix schenkii is a …… fungus

potassium iodide SSKI, antifungal drugs

treatment of sporotrichosis

filaments

dermatophytes grow …….. and can’t infect past the outer layer

systemic mycosis

infection through inhalation of spores, production of TB-like lung infection, rarely disseminates into other parts of the body

histoplasmosis

respiratory infection caused by Histoplasma capsulatum

-dimorphic fungus

histoplasmosis

can be carried by bats and grows well in bat guano and bird droppings, fungus colonizes the lung, spores are inhaled

antifungal drugs

treatment of histoplasmosis

candida albicans

opportunistic pathogen, dimorphic fungus, causes no disease in healthy individuals

candida albicans

mechanism: yeast form engulfed by macrophage → changes to the filamentous form to “pop” macrophage.

neutrophils

macrophages cannot kill dimorphic fungi well but …… can

oral thrush

overgrowth of candida on the tongue, throat

genital

overgrowth of candida in the vagina or urethra

oral or topical antifungal drugs

treatment of candida albicans

candidemia

candida in the blood

candidemia

fever, chills that don’t respond to antibiotic treatment, highly variable symptoms, depending on organ affected, organ failure, death may result without treatment

antifungal drugs

how to treat invasive candidiasis

protozoa

unicellular eukaryotes, no cell wall, usually no photosynthesis

amoebiasis

intestinal disease caused by infectious amoebae

entamoeba

anaerobic parasitic amoebae, motile active form (trophozoite) inside hosts, dormant, hardy, inactive cyst form in soil, water

intestines

entamoeba cysts mature into trophozoites and colonize the ……….

epithelia

occasionally, entamoeba reach the intestinal cell surface and begin killing intestinal ……

amoebiasis

mild infections: diarrhea, mild stomach cramping/pain, severe infections: blood in stool, diarrhea, mild fever. symptoms usually clear on their own but may persist for months, risk of secondary infections

antiprotozoals

how to treat amoebiasis

metronidazole

attacks anaerobic organisms

fecal to oral

amoebiasis is transmitted

giardia

intestinal disease caused by Giardia

giardia

flagellated anaerobic protozoan, specialized structure: a suction cup allowing it to stick to the intestinal wall, motile active trophozoite and cyst form

intestines

where does giardia colonize

block

if giardia grows to large numbers it can …. absorption of fluids and nutrients

giardia

diarrhea, stomach cramps, weight loss, fatigue, greasy floating foul smelling stool, usually self limiting

string test

swallow gelatin capsule w string attached to it, allow capsule to pass into intestines, once capsule dissolves, pull string back out examine string for giardia

antiprotozoals

how to treat giardia

giardia and amoebiasis

intestinal infections caused by protozoans, from a fecal oral route, transmitted by hardy cysts

dysentery

amoebiasis can develop into ….. while giardia infections do not

malaria

caused by plasmodium, transmitted by mosquito

plasmodium

small parasitic protozoan, sexual and asexual reproduction depending on the host

plasmodium life cycle

infecting cells transferred by mosquito bite, initial infection of the liver, eventual infection of RBC, RBC infection amplifies, mosquito bite will pick up sexual cells, sexual reproduction in mosquito, repeat

malaria

FEVER, nausea, fatigue, CHILLS

plasmodium falciparum

plasmodium that is severe and frequently fatal without treatment

quinine and derivatives (chloroquine), artemisinins

treatment of malaria

artemisinins

used in combination w other drugs ACT to treat malaria

helminths

multicellular eukaryotes, worms

schistosomiasis

caused by Schistosoma, a flatworm/fluke, male and female live intertwined, constant production of eggs in the blood causes symptoms, inflammatory disease

schistosoma life cycle

Fluke can penetrate skin and enter the blood stream • Produces eggs that are excreted and hatch in fresh water • Larvae infect particular species of freshwater snail • Freshwater snails release free-living flukes that can penetrate skin • Repeat

schistosomiasis

rash, itchy skin at site of entry (swimmers itch), develop fever, chills, cough muscle aches in response to eggs

antihelminths

how to treat schistosomiasis

tapeworms

flatworm parasites that attach to our intestines, segments contain many eggs and are passed out in feces, can grow to be 6 meters long

tapeworm lifecycle

cysts are fed to livestock, cysts enter undercooked meat, we eat the cysts

tapeworm

some abdominal discomfort, loss of appetite, rare cystercercosis

antihelminths

treatment for tapeworms

ascaris

roundworm intestinal parasites, can grow up to be a foot long and can live in host for 1-2 years

ascaris infection

ingestion of eggs from contaminated water, food, soil, eggs hatch in small intestine, larvae burrow into intestinal wall, enter the bloodstream, migrate to lungs, coughed up larvae are swallowed, re infecting the intestines, mature into egg laying adults

ascariasis

most cause no symptoms, multiple worms cause abdominal discomfort, weight loss, bloating, severe cases may lead to intestinal rupture, heavy infections can lead to coughing/pnemonia

antihelminths

treatment of ascariasis

pinworms

tiny, roundworm intestinal parasite, small worms that infect the lower intestines

pinworm infection

ingested eggs hatch in the intestines, worms migrate to lower intestine/colon, at night worms exit the anus and deposit eggs on the skin