1. HIV and Other Viruses What we all want to avoid getting…

2. Capsid and viral genome enter cell 2 The viral genome (red) functions as a template for synthesis of complementary RNA strands (pink) by a viral enzyme. 3 New virus 8 RNA Capsid Envelope (with glycoproteins) Glycoproteins on the viral envelope bind to specific receptor molecules (not shown) on the host cell, promoting viral entry into the cell. 1 New copies of viral genome RNA are made using complementary RNA strands as templates. 4 Vesicles transport envelope glycoproteins to the plasma membrane. 6 A capsid assembles around each viral genome molecule. 7 Complementary RNA strands also function as mRNA, which is translated into both capsid proteins (in the cytosol) and glycoproteins for the viral envelope (in the ER). 5 HOST CELL Viral genome (RNA) Template Capsid proteins Glyco- proteins mRNA Copy of genome (RNA) ER

3. Reverse transcriptase Viral envelope Capsid Glycoprotein RNA (two identical strands) Structure of HIV

4. Retroviruses 1.RNA virus with a reverse transcriptase A.Enzyme transcribes RNA to DNA 2.Viral DNA enters host DNA (provirus) A.Integrates and becomes permanent in DNA 3.Releases new virus from host cell A.Eventually host cell dies from viral reproduction effects or apoptosis

5. AIDS- Acquired Immune Deficiency Syndrome 1.Immune dysfunction leads to opportunistic infections A.Infections such as pneumonia, tuberculosis, and some rare forms of cancer (e.g. Kaposi’s sarcoma) caused by low immune response 2.HIV is often dormant up to 10 YEARS before symptoms/AIDS develops!!! A.What you do now can kill you just about the time you are starting your life after college, starting a family etc. 3.Viral infections usually controlled by vaccines A.Vaccines are NOT effective with HIV ( rapid mutation)

6. Kaposi’s Sarcoma

7. More on HIV/AIDS 7.HIV is the virus that causes AIDS- Early Symptoms:. A. Rapid weight loss B. Dry cough C. Recurring fever or profuse night sweats D. Profound and unexplained fatigue E. Swollen lymph glands in the armpits, groin, or neck F. Diarrhea that lasts for more than a week G. White spots or unusual blemishes on the tongue, in the mouth, or in the throat H. Pneumonia I. Red, brown, pink, or purplish blotches on or under the skin or inside the mouth, nose, or eyelids J. Memory loss, depression, and other neurological disorders

8. 8. HIV Transmission A.Contact with blood, vaginal secretions, semen, and rarely saliva I.Unprotected sex II.Sharing needles III.Blood transfusions in the past A.Now blood is screened for MANY diseases including HIV B.Is NOT genetic. It is passed from mother to child during childbirth. If you know you have it there are ways to lower your child’s risk of getting it.

9. Influenza-The Flu 9.Various strains 10.Vaccine (B) lasts one year because new strains become more common over time. 11.5-20% of people in the US each year get the flu 12.Influenza A-proteins 13.Influenza B-strains

11. Ebola Hemorrhagic Fever 14.The viruses that cause Ebola are found in Central Africa 15.It has a 50-90% mortality rate 16.Called hemorrhagic because it causes hemorrhaging (uncontrolled bleeding) 17.Symptoms appear 2-21 days after exposure 18.Exposure through body fluids

12. Ebola

13. Small Pox 20.Variola major and Variola minor 21.Variola major worst case senario 22.Mortality: 20–60%—and over 80% of infected children 23.Long term effects on survivors: A.Scars 65-85% B.Blindness/corneal ulceration & scarring, limb deformities 2–5% of cases

16. Herpes 24.HSV-1 (fever blisters) and HSV-2 (genital herpes) 25.Can remain symptom free for long periods of time 26.Has increased 30% in the US 27.An estimated 40 million people have genital herpes! 28.Most people that pass it on didn’t know they had it when they gave it to their partner 29.You do not “get rid” of it

18. Hepatitis 30.There are four types of hepatitis 31.There are several modes of transmission including fecal contamination of food and sexual contact 32.All forms cause inflammation of the liver and can lead to death

20. HPV - Human Papilloma Virus 33.There are more than 100 types of HPV 34.Many are harmless and clear up on their own 35.Some can cause genital warts 36.Some can cause cervical cancer Normal PAP smear PAP smear showing changes associated with HPV

22. Prions Prion Normal protein Original prion New prion Many prions

23. 37. Mad Cow Disease A.Correct name is Bovine Spongiform Encephalopathy (BSE) 37.Transferred from sheep to cows in feed 38.Transferred to humans many through contact (eating) of meat containing or contaminated by brain or spinal cord tissues 39.Similar diseases were already known in human populations (Creutzfeldt–Jakob disease; Kuru)