Neglected Tropical Diseases Flashcards
Define neglected tropical diseases
diseases that generally affect the word’s poor and historically have not received as much attention as other diseases. NTDs tend to thrive in developing regions of the world, where water quality, sanitation, and access to health care are substrandard. However, some are also found in areas of the US with high rates of poverty
What are some general characteristics of NTDs?
- primarily affect women and children
- vector borne or environmental transmittence
- many are zoonotic and employ complex life cycles (> 1 host)
How do you calculate DALY? How do you do this when theres >1 disabilities?
normal DALY: YLD + YLL = (years lived with disease) x (disability weight) + YLL
compunded DALY: YLD (disease 1) + YLD (disease 2 + 1) = YLD(1) + (years with both diseases)(1-(YLD1)(YLD2))
What are the big determinants of health? Describe each one.
- education acess and quality: often form a feedback loop in which reduced access to education increases diseases, and disease inhibits educational outcomes
- health care and quality: accessibility and price have big impacts
- neighborhood and built environments: quality of housing and workplaces
- social and community context: social support systems
- economic stability: ability to contribute to sustainable and viable markets
What type of worm is Taenia solium? Briefly describe its life cycle
tapeworm
life cycle
- eggs in environment –> ingested by human –> cysticerci develop
- eggs in environment –> ingested by pig –> human eat pig meat contamininated with cysticerci –> adult in small intestine
Describe some anatomical features of T. solium adult tapeworm
- scolex –> attatchment
- nurtients absorb through surface
- segements = proglottids
Why is neurocysticerosis underdiagnosed in developing regions?
need MRI/high tech –> not available in lots of countries
Describe how the pork tapeworm cycle can be broken
- always use the toilet
- wash your hands
- go to clinic
- stop pigs from roaming
- train people to properly check meat
- cook meat well
Briefly describe the lifecycle of taenia saginata
eggs in feces in environment –> ingested by cattle –> humans ingest raw or undercooked meat –> adults in small intestine
Describe the cysts of E. granulosus
unilocular – one cyst, one protoscolrex (one worm)
outside layer = laminated layer –> impenetrable
What is the treatment of E. granulosus?
- surgical intervention with injection of 10% formalin
- large doses of Mebendazole –> blocks tubulin polymerization
Describe the differences in E. multilocularis cysts compared to E. granulosus
- multilocular
- no laminated layer
- germinal layer invasive
What is the treatment for E. multilocularis?
- surgery or death
- life-long Mebendazole
Describe the life cycle of Guinea worm
larvae enters copipod –> person drinks water with mature larvae –> larvae devlop into adult worm –> fertilized females travel to lower limbs –> worm busts out of limb when exposed to water
What are the control methods of guinea worm?
- wrap worm around stick and slowly remove it
- use a bucket to allow worm to burst
- filtration of water
- life straws
- clean sustainable water
What is Drancunculus medinesis, when does infection peak, whats the tranmission?
Guinea worm in dogs, dogs get it from eating fish
peaks during fishing season
What is the kinetoplast of trypanosomiasis?
unique DNA structure manifesting as densley packed sereis of circular DNA molecules nar the flagella of the organism
How can T cruzi be diagnoses?
- blood smear
- romanas sign
- agglutination test
- PCR assay: kinetoplast DNA, highly specific –> sensitivity issues
what are the treaments fro T cruzi
benzimadazole and nifurtimox
what is the resevoir host and vector of T. brucei (african sleeping sickeness)
reservoir = cattle
vector/tranmittance = tse tse fly
what are the two human forms of african sleeping sickness and the cattle form?
human: G. gambiense (chronic) and R. rhodesinse (acute)
cattle: T brucei
what is a big symptom of african sleeping sickness?
sleep/wake cycle reversed and “winterbottoms” sign
What are the challenges of dealing with NTDs?
- human migration
- less research funding
- types of vaccones required
- hidden populations
why are vaccines difficult to generate for worms?
- thick skin
- highly complex
- type 2 immune response –> vax can create allergic shock
