APES Tropical Infectious Diseases Research - Shope

Tropical Infectious Diseases - Research




• A – Trypanosomiasis (sleeping sickness)
o vector: Tsetse fly

o symptoms
• massive stimulation of immune system
• generalized pain, weakness, cramps
• swelling of neck lymph nodes
• apathy, mental dullness
• tremors, convulsions
• sleepiness, coma
• rapid weight loss

o Sub-Saharan Africa
o 20,000 new cases a year



• B – Schistosomiasis
o parasitic disease
o leads to chronic ill health
o Central China & Egypt… other developing countries as well
o documented existence since the time of the Egyptian pharaohs
o indicated by blood in urine or serious complications involving the liver and spleen
o infected by contact with water used in normal daily activities (hygiene, swimming, fishing, irrigation, etc.)
o infected individuals may contaminate their water supply with feces or urine due to lack of information or insufficient attention to hygiene



• C – Lassa Fever
o acute viral illness
o West Africa
o zoonotic (rodent)

o transferred through…
• direct contact with rodent’s urine or droppings
• touching objects or eating food contaminated with these materials
• open cuts or sores

o endemic (constantly present)
o mild, no symptoms in 80% of infected people

o symptoms present 1 – 3 weeks later
• varied and non-specific
• fever
• sore throat
• back pain, abdominal pain
• cough
• vomiting, diarrhea
• hearing loss, tremors

o 100,000 – 300,000 new cases per year



• D – Filariasis
o caused by parasitic worms transmitted by mosquitoes
o extremely rare in Western countries

o biggest symptom: elephantiasis
• thickening of skin and underlying tissues
• caused when parasites lodge in the lymphatic system
• mainly affects lower extremities
• not known to be fatal, though it can cause a fair amount of pain

o other symptoms
• swelling (lymph nodes, arm, leg, etc.)
• fever, aches, pain
• thickened skin
• warty skin appearance

o endemic in tropical regions of Asia, Africa, Central America, South America
o 120 million people infected



• E – River Blindness
o world’s second leading infectious cause of blindness
o caused by a parasitic worm that can live in the body for up to 15 years

o symptoms
• skin: intense itching, swelling, inflammation, loss of elasticity
• blindness
• skin cancer

o West and Central Africa
o about 18 million infected… 300,000 irreversibly blind



• F – West Nile Virus
o tropical and temperate regions
o mainly infects birds
o main route to human infection: via mosquito

o symptoms
• nausea, vomiting, loss of appetite, diarrhea
• tiredness, decreased level of consciousness (near-coma), coma
• stupor, disorientation
• fever, headache
• skin rash (trunk of body)
• neck stiffness
• tremors, convulsions
• muscle weakness, paralysis

o symptoms generally last for a few days
o deadly if it enters the brain



• G – SARS
o Severe Acute Respiratory Syndrome
o has been one near pandemic in 2002/2003
o originated in China

o symptoms
• initially are flu-like
• high fever (above 100.4F)
• lethargy
• muscle pain
• gastrointestinal symptoms
• cough, sore throat

o caused by virus from same family as the common cold
o much more harmful to animals than humans
o airborne



• H – Trichinosis
o parasitic disease
o caused by: eating raw or undercooked pork and wild game infected with larvae
o person-person spread doesn’t occur

o symptoms (usually 10 – 14 days after infection)
• fever
• muscle soreness
• pain and swelling around eyes
• thirst
• profuse sweating, chills
• weakness, tiredness
• chest pain

o partial immunity may develop
o fatal if not treated



• I – Prions
o infectious agents composed of only protein
o cause a number of diseases in a variety of animals
o cause neurodegenerative disease
o “holes” in normal tissue structure
o very long incubation period
o once symptoms appear, the disease progresses rapidly… leading to brain damage and death

o symptoms include
• convulsions
• dementia
• ataxia (balance and coordination dysfunction)
• behavioral or personality changes

o primary transmission unknown… may be ingestion