Viruses and HIV

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Reverse Transcriptase – turns RNA into DNA (this makes HIV a retrovirus); DNA instructs cell to make more viruses

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Virus enters cell through endocytosis

Virus replicates RNA to DNA with reverse transcriptase

HIV Making Factories

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DNA enters nucleus & binds with host DNA

New virions exit cell through exocytosis to infect other cells (notice cell isn’t destroyed)

mRNA is created (carries instructions for making new viral proteins) and leaves nucleus

Uses host cell’s enzymes to make new viruses

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How Is HIV Spread?

Sexual contact

Sharing contaminated needles

Blood transfusions

Breast feeding (mother to baby)

Mother to baby during pregnancy or birth

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Think about it…

In the US, there is better than a 1/1000 chance of contracting HIV during unprotected sex

A person can be contagious for more than 10 years before any sign of the disease is apparent

HIV becomes AIDS when the number of immune cells drops below a predetermined number

No one dies from HIV or AIDS; people die from secondary infections (ranging from the common cold to cancer)

More than 3 million people (size of Chicago) die each year

There are approx. 14,000 new cases of HIV worldwide every day