Parasites. Flashcards
Pathogen.
Organisms like Bacteria or viruses who cause disease and can be transmitted from one person to another.
What is a parasite?
An organism on or in a host for their advantage without contributing to survival of host.
VectorsZ
Organisms that carry Te disease from one pathogen to another
Carrier.
An individual showing no symptoms of disease but can pass disease to another
Reservoir.
The place where a pathogen is normally found.
Endemic.
A disease which is always present at the lower levels in an environment.
Epidemic
When there is a significant increase in disease cases often associated with rapid spreads
Transmission via food or water
When ingest only material gets icky animated from poor hygiene or sanitation. Can be spreads by dirty or undercooked water or meat.
Contagious disease.
Aka droplet INFECTION. Microorganism expelled in saliva an mucus drops. Main way respiratory disease are spread
Infectious diseases
A disease that can be passed form host to host.
Salmonella sp
Gram negative rod shaped bacteria.
From contaminated food.
Eating foods undercooked, raw or with unhygienic preparation.
Toxin irritates gut lining.
Diarrhoea and vomiting
Oral rehydration, antibiotics.
Cook food thoroughly, store in cool conditions and avoid contaminated carriers.
Antibiotic treatment available but not usually given out to prevent resistance buildup.
Vaccine unavailable as over 2000 antigenic types.
Spread at animal slaughter from intestine reservoir.
Organism multiplies during storage.
Analysis of antigenic types
Cholera
Vibrio cholerae
Gram negative bacteria
Contaminated water
Drinking contaminated water.
Affect gut lining causing diarrhoea and severe dehydration.
Rehydration, antibiotics, vaccine.
Water treatment, hygienic disposal of faeces, clean water provision.
Antibiotic treatment available but tet largely dehydrate.
Vaccine provides temporary protection,
Salmonella is spread how? Analysis of what can do what?
Salmonella is spread at animal slaughter from intestinal reservoir.
Organism multiplies during storage
Analysis of antigenic types allows tracing source of infection.
Tuberculosis CAN BE SPREAD IN CROWDED CONSITIONS.
Mycobacterium tuberculosis Bacterium. Infected people and this environment. Inhaling airborne droplets from infected. Drinking infected cow's milk. Lung and lymph nodes. Persistent cough, night sweats, chest pain, coughing up blood, fever. Giant course of antibiotics. Bcg vaccine for children. Avoiding infected people, Tb test them cows.
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Influenza
Virus.
Infected people.
Inhaling airborne droplets from infected.
Upper respiratory tract
Headache sore throat, fever, high body temp.
Vaccine the elderly, symptoms treated with aspirin
Hygienic practices like using tissue.
Quarantine the infected
Antibiotics don’t work
Due to emergence of antigenic types vaccine not always available.
Malaria caused by what?
Is it endemic anywhere?
How is it so deadly?
Caused by plasmodium so a protoctistan parasite.
Endemic in some subtropical areas.
The disease is caused by two species within which are many antigenic types.
Initially invaded liver cells and then multiplies in red blood cells bursting out of them with more parasites causing severe fever.
Female mosquito vectors transmit parasite to new victims .
Malaria prevention?
Mosquito nets
Repellent
Protective clothing
Mosquito eliminatiipn.
Drain swamps. Introduce fish to breeding ponds. Torch with diesel oil. Spray insecticides Infect with bacteria. Sterilise males.
Malaria treatment.
Attack where free in blood.
Quinine or synthetic anti malarial with purpose.
Vaccines however difficult to develop as numerous antigenic types.
Plasmodium is a bit protected against antibiotics.
Plasmodium is affected by drugs outside blood cells but not inside and have side effects.
Antibodies are only able to work when outside blood cells so limiting target stages for vaccine.
Schistosomes
Endoparasitic flatworms
Adults have suckers allowing attachment to venule walls.
Do not move so do not require locomotive organs.
Adult flukes cover themselves in host antigens taken from blood cells avoiding immune detection.
Eggs have resistant coat to survive burrowing into bladder.
Females lay a large number of resistant eggs increasing secondary infection chance.
Fertilised adult segment can break off carrying Vast quantities of eggs.
Taenia solium
Endoparasite
Embryos protected with resistant cyst and hard outer coat providing protection.
Attach to hosts intestinal wall using a scolex with hooks and suckers.
No organs for locomotion or sense organs because of digestive sustem’s stable environment.
Resist host’s immune system with thick outer cuticle.
Secrete enzyme enhibitors.
Each body segment contains both male and female reproductive organs. And hundreds of eggs.
Pediculus.
Enctoparasite.
Feed on blood sucked from scalp capillariesZ
Adults have claws to hold onto individual hairs preventing them being washed off.
Lay eggs which are glued to individual strands.
Protected by resistant coats.
Hair washing does not remove eggs.
Do not have wings so walk from host head to host head.
Ascaris.
Endoparasite.
Ascaris do not attaché as Each host contains several worms
Does not move so no locomotive organs needed.
Eggs have resistant coat to survive in soil.
Adults have protective outer layer resistant to digestive enzymes.
Resistant coat of eggs protects agai at digestive enzymes and extreme ph.
Adult females lay many eggs increasing secondary host chance infection.
