Brain Worms to TB Clubs: Making a Difference to Global Health Flashcards
What is intestinal taeniasis?
An intestinal pork tapeworm infection.
Who is the end host of intestinal taeniasis?
Humans only.
When do people present with intestinal taeniasis?
Usually asymptomatic, rarely present.
How long will an intestinal taeniasis live for?
Can live for many years.
How long are intestinal taeniasis?
1-2m, but can grow up to 30m.
How are humans infected with intestinal taeniasis?
Infectious eggs passed in human faeces - free or intact segments viable in the soil/water for many months.
Pigs eat tapeworm eggs in the human faeces.
Parasites migrate to the pig tissues and encyst (porcine cysticercosis) - humans eat these pigs (parasitised ‘measly’ pork)
What is the most common way that humans contract intestinal taeniasis?
Eating undercooked infected measly pork.
What hampers the eradication of intestinal taeniasis? (3)
Asymptomatic taeniasis.
Use of pigs as sanitisers.
Clandestine slaughter methods.
Can vegetarians contract intestinal taeniasis?
Yes - present in all food contaminated with infected faeces.
It affects vegetarians and meat eaters alike, all tissues are affected.
What is the most significant organ affected by intestinal taeniasis?
The brain. (Human cysticercosis)
What is it called when intestinal taeniasis affects the brain?
Neurocysticercosis.
What is the most common reason for symptomatic taeniasis?
Brain cysticerci.
What dictates the clinical features of neurocysticercosis? (3)
Dependant on the immune response, the number and the site of the cysts.
What are some consequences of neurocysticercosis? (7)
65% - epilepsy 24% - raised intra-carnival pressure. 22% - headache. 14% - altered mental state. Also: stroke, blindness, spinal disease.
What is the natural history of neurocysticercosis?
Usually, living cysts are asymptomatic for the first years after infection.
Symptoms mark cyst degeneration causing eosinophilic cellular influx and inflammation.
Living cysts actively evade and suppress inflammation until they die or are killed (sequestration/fibrous encapsulation/ concomitant immunity/ molecular mimicry/ masking modulation of host immunity)
How is neurocysticercosis managed? (5)
Anticonvulsant therapy usually effective (advise not to drive, etc…)
Ventriculo-peritoneal shunt if hydrocephalus.
Cestocidal drugs (albendazole or praziquantel).
Steroids for inflammation around dying cysts.
Family screening for taeniasis and cysticercosis.
What must be given with cestocidal drugs in the treatment of neurocysticercosis?
Steroids for inflammation - can be fatal otherwise.
How do cestocidal drugs for neurocysticercosis work? (2)
Accelerate disappearance of viable cysticerci.
Cause transient inflammation around viable cysticerci.
What scenario are steroids most effective for in the treatment of neurocysticercosis?
Partial effect for cyst degeneration/cestocidal therapy.
What are steroids lead effective for in the treatment of neurocysticercosis? (2)
Chronic granulomatous inflammation. Heavy infections - cestocidal therapy may be fatal.
What are some cysticercosis control interventions? (7)
Meat processing methods. Slaughter house control. Pig treatment. Vaccination. Health education. Sanitation: Latrines. Taeniasis treatment.
A person who follows the orthodox Jewish religion who has always been a strict vegan develops seizures whilst living in rural Latin America. Is cysticercosis a potential cause?
Yes - faecal contamination of vegetables possible.
What age group is TB most prevalent in in very low income countries?
Very young, decreasing prevalence with increasing age.
What age group is TB most prevalent in wealthy countries?
Middle aged - decreasing prevalence in the very young and very old.
What percentage of the global population is infected with TB?
0.12% per year.
What is the epidemiology of TB infection?
1.8 million deaths/year.
What percentage of TB infections occur in HIV positive individuals?
87%
What percentage of TB is MDR?
Only 4%
How do you diagnose TB Infection?
MDR/XDR-TB Colour Test
What steps are involved in the TB Colour test? (4)
- Mix - spit with disinfectant.
- Drip - on plate, seal and incubate (detection quadrant, quinolone quadrant, rifampicin quadrant, isoniazid quadrant)
- Look - for red colour
- Check dots have TB cording shape using a magnifying glass.
What is the percentage transformation of TB to MDR-TB during drug therapy?
6.7%
What are the two biggest risk factors for TB infection? (2)
HIV infection.
Malnutrition.
Is HIV or malnutrition a larger risk factor for TB acquisition?
Malnutrition. Poverty is the strongest risk factor for TB.
What single factor has a greater impact on transmission and incidence of TB?
Socioeconomic development.
What are the treatment challenges with TB? (6)
Diagnostic delay. Treatment response. Treatment adequacy. Treatment adherence. Index patient infectiousness. TB strain virulence.
What are the environmental challenges with TB? (7)
TB strain environmental survival. Airborne transmission and ventilation. Airborne transmission and UV light. Airborne transmission and humidity. Duration of contact with TB patients. Closeness of contact with TB patients. Crowding.
What are the personal risk factors for TB infection? (12)
Nutritional status. Drugs and alcohol use. Diabetes. Stress. Depression. Age. Sex. Host genetics. HIV infections and AIDS. Intestinal parasites. BCG vaccination. Environmental mycobacteria and other co-infections.
What are the socioeconomic interventions for TB control? (2)
Cash and food transfers: microcredit, training and microenterprise.
Social support: health promotion, education, empowerment and advocacy.
