Lecture 4-2: Viruses cont., Prions, and Viroids

Some viruses that have had a major impact on health include

Ebola, HIV, SARS

Ebola is an

RNA virus, helical, has envelope, very deadly (up to 90%),

Symptoms of Ebola are

headache, fever, fatigue, sore throat in beginning. impaird liver and kidney function, rash, vomiting, internal and external bleeding in later stages.

Ebola is strongly connected to

bats

A spillover happens when

a human contracts virus from animal reservoir (hunting/food processing)

Ebola in humans is usually spread by

body fluid (funeral practice, unprotected health care worker)

What causes AIDS?

Human Immunodeficiency Virus

The main danger of HIV is

the impacts on the immune system

HIV targets ____ which usually have the function of activating B cells that produce antibodies and activate killer T cells that destroy infected cells. (huge impact)

helper T cells

People with AIDS die of

secondary infection

HIV is an ____ virus with an ____

RNA, envelope

SARS stands for

Severe Acute Respiratory Syndrome

SARS is caused by

SARS coronavirus

The symptoms of SARS are

flu-like, fever, lethargy, myalgia, cough, patchy x-rays, (fever>100.4 was only common system)

The SARS outbreak only lasted from

2002-2003

COVID 19 is a very ____ respiratory disease and was detected in _____ in December 2019.

contagious, China

COVID is different from SARS because it is

more easily spread

You can contract COVID 19 from

droplets transferring from hands to eyes and mouth, respiratory secretions

COVID 19 symptoms include

dry cough, aches and pains, fever, fatigue, difficulty breathing, runny nose, sore throat, diarhea

Symptoms of a cold are different from COVID because

they don’t have dry cough or diarrhea, have sneezing and stuffy nose

Hay Fever symptoms include

fatigue, dry cough, allergy, difficulty beathing, sneezing, runny nose, stuffy nose, watery eyes

Influenza symptoms include

fever, fatigue, dry cough, aches and pains, sneezing, runny nose, sore throat, diarrhea

What were the 3 main COVID 19 vaccines?

Pfizer, Moderna, Johnson and Johnson

The Pfizer vaccine is a

2 dose, mRNA vaccine, creates immune response

The Moderna vaccine is a

2 dose, mRNA vaccine, creates immune response

The Johnson and Johnson vaccine

1 dose, viral vector vaccine

A mRNA vaccine is composed of

messenger RNA that gets your cells to produce proteins that are basically the same proteins that the virus produces, which makes your body start to make an immune defense 

A viral vector vaccine has a

weakened virus that instructs cells to make proteins (COVID 19) makes

An mRNA vaccine does not contain

a live virus

What are prions?

infective proteins, fold abnormally, normally affect nervous tissue, cooking will not destroy them, can affect humans and animals, can be spread by infected meat products

How do prions come about?

an infective protein comes in contact with a normal, healthy protein and then transforms it into another infective protein, gives it a spongy look

What is BSE?

Bovine Spongiform Encephalopathy “mad cow disease”, caused by prions, chronic degenerative disease that affects CNS of cattle, spongy effect on nervous tissue, can be passed to humans, can cause seizure and death

What is CWD?

Chronic Wasting Disease, affects deer, caused by prions, issues with walking 

What is Scrapie

caused by prions, affects sheep

Transmissible Mink Encephalopathy

caused by prions, affects mink

Feline Spongiform Encephalopathy

caused by prions, affects cats

Ungulate Spongiform Encephalopathy

caused by prions, affects ungulates

BSE was spreading badly because

farmers would feed healthy cows the infected slaughtered byproducts

What is Creutzfeldt-Jakob Disease?

CJD, affects humans, caused by virions, spongy brain tissue, lose ability to think and move properly, memory loss, fatal within 1 year

What is Variant Creutzfeldt-Jakob Disease?

vCJD, virion disease that affects humans, 

What is Gertmann-Straussler-Scheinker Syndrome?

caused by virions, affects humans

What is Fatal Familial Insomnia?

caused by virions, affects humans

What is Kuru?

caused by virions, affects humans, discovered in Fore tribe, headache, joint pain, difficulty walking, death in 1-2 years, cannibalism eating brain

What are the 4 kinds of CJD

sporadic/classical, familial/infectious, Iatrogenic, variant

Sporadic/classical CJD

affects mainly people >50s, ataxia, dementia, spongiform changes

Familial/infectious CJD

inherited mutation in gene, younger age of onset, symptoms similar to sporadic, can live longer

Iatrogenic CJD

contamination during brain surgery or cornea transplant or duramatter grafts, age dependent on exposure source, symptoms are same as sporadic

Variant CJD

exposure to BSE cattle disease, younger age of onset, longer duration of symptoms, psychiatric symptoms, daisy-like plaques in brain tissue

What is a viroid?

only made of genetic material [single stranded RNA], don’t directly impact humans, no protein coat, mainly seen in plants, spread though contact between plants, (Ex: potato spindle viroid)- misshapen fruit