Unit 3 -Microbiology (Viral Diseases, Bloodborne Diseases) Flashcards
Viruses ___ be treated with antibiotics
Viruses CAN’T be treated with antibiotics
What happens when a virus invades a host cell?
Replicates then destroys host cell so virus is released into body
Host cells may be …
Human
Plant
Animal
Bacteria
HIV infects which specific cells?
CD4
Hepatitis infects which specific cells?
Liver cells
What % of HIV infected mothers pass virus to babies
25%
This virus during pregnancy is a major cause of mental disability, blindness, and impaired hearing in children
CMV aka Cytomegalovirus
Term for a virus in a dormant state
Latent
when virus becomes integrated into the nucleic acid of the host cell it is now known as?
a provirus
what can reactivate a latent virus?
stress
infection with another virus
UV light
5 ways viruses can be transmitted
direct contact insects blood transfusions contaminated food/water inhalation of droplets (coughing/sneezing)
Viruses in the environment can be easily killed with?
chemicals
4 common chemicals that kill viruses in the environment
chlorine
iodine
phenol
formaldehyde
Where do scientists believe HIV came from?
Chimpanzees from Western Africa
first human infection as far back as late 1800s
How does HIV affect the immune system?
HIV infects T-cells and kills them
What are T-cells?
Cells that are primarily responsible for immunity
How is AIDS developed?
person with HIV becomes ill with serious illness/infection
Most common ways of HIV transmission
Sexual Contact
Needle Sharing
When can a baby of an HIV+ mother be infected?
before birth
during birth
breast feeding
There has been a steady decline of HIV infection due to?
Antiretroviral Therapy (ARV)
What is Antiretroviral therapy? (ARV)
Medication which slows HIV replication = lowered viral load
Amount of HIV in your blood
Viral load
How can AVR help people with AIDS?
can prolong life expectancy
What was HAV formerly called?
Infectious Hepatitus
How is HAV transfered?
fecal oral
People who recover from HBV but can still transmit the virus are known as?
HBV carriers
What is the Hepatitis B Surface Antigen? (HBsAg)
What does it mean if it is present?
Surface protein of HBV - marker to detect infection
if present = infected
What is the Hepatitis B Surface Antibody?
HBsAb or anti-HBs
What does it mean if it is present?
antibody formed in response to Hepatitis B Surface Antigen
immune system has created antibody for long term immunity to HBV
How can you accuire Hepatitis B Surface Antibodies?
through infection and recovery of HBV or Vaccine
How is HBV transfered?
Parenteral
Blood borne
How is HCV transfered?
Parenteral
Blood borne
How can HCV ve detected?
Raised levels of ALT levels
Aniline aminotransferase
When did blood donations start to be screened for HCV?
1992
HDV is a co-infection of?
Hep B
four major herpes viruses
HSV - herpes simplex virus
HZV - herpes zoster or varicella-zoster virus
CMV - cytomegalovirus
EBV - epstein-barr virus
HSV is broken into?
HSV Type 1
HSV Type 2
HSV Type 1 is broken into?
Primary Herpes - 1-3 yo
Recurrent Herpes Labialis
How long does active HSV-1 general last?
7-14 days
What can activate HSV-1?
Stress
illness
Sun
% of HSV-2 infected newborns that will be severely infected or die
85%
% of newborns that will be infected when passing through HSV-2 infected birth canal
50%
virus responsible for chickenpox/ shingles
Herpes Zoster virus
how is HZV transfered?
saliva
direct contact with lesions
Which virus flares up in summer and continues into fall in North America?
West Nile Virus
What is the easiest way to prevent West Nile?
Prevent mosquito bites
Example of an EPA register active ingredient for insect repellant
Deet
What steps can you take to prevent mosquito bites?
- Use repellent with deet
- wear long sleeves/ stay in at dusk and dawn
- make sure you have good screens on your house
- get rid of stagnate water
odds of developing serious west nile symptoms
1 in 150
at what age+ are people more likely to develop serious West Nile symptoms?
50
When/where was the first report of SARS?
Asia 2003
Where did SARS spread to before it was contained in 2003?
24+ Countries in: North America South America Europe Asia
How many people world wide became ill with SARS during 2003?
Died?
Ill = 8098
Died = 774
How does SARS spread?
Droplet spread from sneeze/coughs lands on mucous membrane of next person
direct and indirect (contaminated surface)
What does Gardasil vaccine protect against?
4 HPV types:
2 - cause cervical cancer
2- cause 90% warts
approved for M/F 9-26 y
What does Ceravix vaccine protect against?
2 HPV that cause cervical cancer
approved for F 10-25y
HPV is the leading cause of what kind of cancer?
Oral Phaynx
HPV16 manifests where?
Posterior of mouth
When was Ebola first discovered?
1976
How long are you infectious for if you have Ebola?
as long as virus is still in your blood
When/where was the first outbreak of Norovirus?
1972 Ohio
How is Ebola transferred?
wild animal to human
How is Norovirus transferred?
From stool/vomit
Direct/indirect contact and contaminated food/water
