Lecture 5 Flashcards
Ziika Virus
Entebbe, Uganda
Rhesus Monkeys - Yellow fever
Take virus and Filter as to Trap Bacteria. Therefore Filtrate was sterile except for Viruses and proteins.= Proof that there were viruses in monkey 766’s Blood.
Filtrate then injected into mice. 6/7 fell sick. = Proof viruses were Transmissible and cause illness in mice
Thought was yellow fever, but came and went quickly.
If same mice were injected with blood, Stopped mice get sick second time round. Antibodies. - developed immunity. Didnt protect form Yellow fever.
Looks same as yellow fever- rounded circles.
Ebola: long worm like.
Studies in other parts of Africa and Asia found Zika infected mosquitos
People in Africa and Asia often had antibodies against zika virus
Yap Island Ziika outbreak: Many people had antibodies but no recollection of illness (1 illness:4.4 asymptomatic/subclinical)
-symptoms(minor, short lived, flu like) through to arise as a result of immune system REACTING to ziika infection (not due to virus destroying tissue)
-Aedes mosquitos, widespread, Flave viruses
Endemic: Africa and Asia- disease always present
Microcephaly incidence 20x (rates or new cases) - correlation between zika and microcephaly. Head circumference of new born baby, can be normal or can have limited development and learning disabilities
Virus
Infect living things- including bacteria
Array of shapes and sizes (Looks same as yellow fever- rounded circles.
Ebola: long worm like.)
1. All viruses are a piece of Nucleic Acid (RNA or DNA) - single or double stranded. Replicates.
2. All Capsid: Virus protein coat. (proteins that are encoded by viral nucleic acid)
3. Some Envelope: Derived from host cell. -piece of Plant cell if plant virus. Virus proteins embedded on the envelope
What are the requirements to Define a virus official?
- Compatible symptoms
- Detection of virus RNA in blood by PCR (virus RNA only replicating if you have the virus)
- detection of immune antibodies specific for zika
Microbe
a microscopic entity
virus, bacteria, fungus, animal
Pathogen
Entity something capable of generating disease
- usually a microbe((sub)microscopic entity)
- macroscopic pathogen = worms. scabies.
Endemic
something/disease regularily found in a place or population
Epidemic
more illness than before
-usually an infection
Pandemic
an epidemic spread across vast reaches/continents
Infection
the new presence of a microbe
- colonisation subclinical disease
- doesnt have to end up in disease. could just be temporary colonisation (staphylococcus aureus: 15% of population always lives on those people(colonisation) - strain which causes colonisation changes a few times a year)
Infectious disease
Symptomatic illness/disease caused by a pathogen
interaction with a microbe that causes damage to the host
asymptomatic(immune system fighting back) or symptomatic
-most are a combination of the two
Endogenous
originates within an organism
-appendicitis
Infectious disease arises from colonising pathogen or flora
-urinary tract infection.bacteria living in gut. crawls into bladder and causes infection
-infections of abdomen (appendicitis, gall bladder infection, colonsisitis, liver abcess)
Exogenous
present but originated outside an organism
- Tuberculosis
- flu/influenza cough and inhale (comes from environment or another person)
Subclinical
infectious disease that triggers the immune system
-but doesn’t cause symptoms
Transmission
manner of spread of a microbe
-direct or indirect
Flavivirus
a type of RNA virus that causes a wide range of diseases, often spread by Pedes genus mosquitoes/ Yellow fever Dengue Zika Hepatitis C)