good viruses some infect and destroy bacterial cells [e.g. prevent bacterial infections] ...
TRANSCRIPT
GOOD VIRUSES
Some infect and destroy bacterial cells [e.g. prevent bacterial infections]
Biological control [get rid of insect pests] Used as vectors in biotechnology [help to
transfer genetic material from one organism to another]
VIRUSES CAUSING DISEASES
Common cold Flu AIDS Bird flu Polio
Electron micrographs of viruses.
HIV Aeromonas virus 31 Influenza virus
Orf virusHerpes simplex virusSmallopx virus
Study only ONE disease
EITHER: HIV RABIES INFLUENZA
Effects and management
RABIES
HIV (Human Immunodeficiency Virus)HIV (Human Immunodeficiency Virus)
Is a virus that:Is very fragileDoes not live long outside of the human bodyAttacks the immune systemIs spread primarily via unprotected sex and shared needles
Is a virus that:Is very fragileDoes not live long outside of the human bodyAttacks the immune systemIs spread primarily via unprotected sex and shared needles
When the immune system becomes very affected, the illness progresses to AIDS = Acquired Immune Deficiency Syndrome
When the immune system becomes very affected, the illness progresses to AIDS = Acquired Immune Deficiency Syndrome
HIV AIDS
CAUSESCAUSES
HIV virus infects and destroys T lymphocytes [CD4 cells] in the immune system
These cells play a vital role in immunity
HIV virus infects and destroys T lymphocytes [CD4 cells] in the immune system
These cells play a vital role in immunity
HIV LIFE CYCLE
• T cells carry the CD4-antigen on their surface• Antigen = a protein molecule• HIV recognizes and combines with the CD4-antigen• It then enters the CD4 cell [host cell]• HIV uses the host cell material to make new viruses• These infect new CD4 cells• CD4 cells are destroyed• Other cells involved in immunity are not activated• Individual becomes susceptible to infections
HIV LIFE CYCLE
• T cells carry the CD4-antigen on their surface• Antigen = a protein molecule• HIV recognizes and combines with the CD4-antigen• It then enters the CD4 cell [host cell]• HIV uses the host cell material to make new viruses• These infect new CD4 cells• CD4 cells are destroyed• Other cells involved in immunity are not activated• Individual becomes susceptible to infections
HOW HIV IS SPREAD
During sexual intercourse Or contact with infected blood, semen and vaginal
secretions
Blood transfusions
Infected injecting equipment Needles, syringes or skin piercing equipment
Mother to infant transmission During pregnancy, labour, delivery or breast feeding
How Can I Prevent Myself From Getting It?
HIV and AIDS
By practicing good standard precautions in all circumstances, you can prevent catching the AIDS virus. Currently, there is no vaccine to prevent the disease, and no current drugs available to cure it. Just be careful:
HIV and AIDS
By practicing good standard precautions in all circumstances, you can prevent catching the AIDS virus. Currently, there is no vaccine to prevent the disease, and no current drugs available to cure it. Just be careful:
1. Do not have unprotected sex.
2. Know your sexual partner.
3. Do not share any type of needle.
4. Always use standard precautions for every individual you care for.
1. Do not have unprotected sex.
2. Know your sexual partner.
3. Do not share any type of needle.
4. Always use standard precautions for every individual you care for.
HIV-1 StructureHIV-1 Structure
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EFFECT OF HIV ON THE BODYEFFECT OF HIV ON THE BODY
IMMUNE SYSTEM WEAKENS Lack of energy Rapid weight loss Frequent fevers and sweats Fungal infections occur – oral or vaginal Shingles Skin rashes Diarrhoea Blemishes on the tongue or mouth or throat
IMMUNE SYSTEM WEAKENS Lack of energy Rapid weight loss Frequent fevers and sweats Fungal infections occur – oral or vaginal Shingles Skin rashes Diarrhoea Blemishes on the tongue or mouth or throat
OTHER EFFECTS OF AIDSOTHER EFFECTS OF AIDS
Sufferers experience feelings of ostracism, alientation and loneliness
Negative effects on the economy Family network breaks down High financial costs to individuals
Loss of earning Travel expenses Burial expenses
Financial costs to government Purchase of drugs Maintenance of health facilities Loss of income due to lost days work
Sufferers experience feelings of ostracism, alientation and loneliness
Negative effects on the economy Family network breaks down High financial costs to individuals
Loss of earning Travel expenses Burial expenses
Financial costs to government Purchase of drugs Maintenance of health facilities Loss of income due to lost days work
MODERN TREATMENTMODERN TREATMENT
Anti-retroviral treatment Drugs which stop viral replication
Treatment of opportunistic infections Drugs are used to treat these infections
Boosting the immune system Slow down the effects of HIV infection Good diet, etc
Anti-retroviral treatment Drugs which stop viral replication
Treatment of opportunistic infections Drugs are used to treat these infections
Boosting the immune system Slow down the effects of HIV infection Good diet, etc
THE END