Eradicated Diseases Flashcards
World wide vaccination of smallpox
1967
Types of small pox (variola)
Minor
Major
Hemmorrhagic (100%)
Malignant
Smallpox genome
Double stranded linear DNA
Enveloped
has DNA dependent RNA polymerase
Smallpox genome shape
Dumbbell shaped
Transmission of small pox
Air droplets
Contact with rash or scab
contact with fomites
How does smallpox enter host cells?
Uses Glycosaminoglycans (GAGs) to attach to respiratory cells Envelope fuses with cell membrane Core of virus released into cytoplasm where DNA replication and transcription take place
Smallpox family
Poxviridae
Vaccinia
form of cowpox virus that has been used as live viral vaccine against smallpox
Smallpox site of replication
host cytoplasm so must have own enzymes for DNA and mRNA synthesis
Guarnieri inclusion bodies
What smallpox virions are assembled into
Discoverer of smallpox
Edward Jenner
Smallpox symptoms
Begins with fever, malaise, chills
Synchronized maculupapular rash
Smallpox incubation
2 weeks then symptoms start rapidly
Smallpox diagnoses
Clinical presentation
PCR
Smallpox treatment
Vaccine–done in 1980
Methisazone
Cidofovir
Methisazone or Cidofovir
may work as prophylaxis against smallpox infection
Poliovirus symptoms
Flaccid paralysis
Poliovirus transmission
Fecal to oral
poor sanitation and crowded cities
Polio family
Picornaviridae
Polio genome
nonenveloped
ss + RNA
Does polio damage cells or is it immune mediated?
Polio is cytolytic so it causes direct damage to infected cells
4 types of polio infection results
Asymptomatic
Abortive
Nonparalytic
Paralytic
Asymptomatic
Virus only replicates in GI Tract
90% of case
competent immune system keeps at bay with antibody production
Abortive polio
5% of individuals
get first part of infection: malaise, vomiting, fever, sore throat, headache
Nonparalytic polio
2%
viremia to brain and meninges
stiff neck, vomiting, aseptic meningitis
Polio diagnoses
Clinical presentation
Throat and rectal swabs: takes 1 week to culture and see effects
RT-PCR on tissues and body fluid
Polio prevention
Inactivated vaccine: can shed and cause polio in others
Oral vaccine: live attenuated, induces humoral immunity, polio can still replicate in GI tract
HIV symptoms
Weight loss Diarrhead Sore throat Swollen lymph nodes Illnesses that a healthy immune system could prevent
HIV types
HIV-1: more infective, major cause
HIV-2: poor capacity for transmission
HIV Transmission
Unpredected sex sharing of needles mother to child blood transfusion organ transplant
HIV genome
enveloped
two copies of + single strand RNA
What cells does HIV infect?
First infects macrophages but travels to the lymph nodes where CD4 T cells are infected
HIV diagnoses
Serological diagnoses by ELISA testing
When positive, confirmed by Western blot
Why is an HIV vaccine difficult?
The lipid envelope has glycoproteins that undergo antigenic variation
HAART
highly active antiretroviral therapy
uses a combination of antiviral drugs
HIV treatment
HAART uses reverse transcriptase inhibitors and viral protease enzyme inhibitors
What test is best predicative of HIV prognosis in the long run? Short run?
long run: viral load (amount of HIV in blood)
short run: CD4 lymphocytes count
Most common severe ocular complication of AIDS
CMV retinitis caused by the herpes virus CMV
Ebola family
filoviridae
5 ebola strains
Zaire Sudan Tai Forest Bundibugyo Reston
Ebola diagnoses
Postive for virus antigen via RT-PCR or by IgM antibodies
Ebola transmission
blood
aerosols
semen
Ebola symptoms
fever sore throat severe headache muscle pain vomiting diarrhea impared liver and kidney function
How does ebola disrupt innate immune response
Disables IFN 1 and 2 so antiviral state can’t be induced and NK cells can’t be activated
What does ebola do to dendritic cells
prevents them from maturing and making cytokines. They can’t activate T-cells for the adaptive immune response to take place
Ebola treatment
supplemental IFN
introducing GP1,2
