Epidemiology and Epidemiology and control of control of

HIV/AIDSHIV/AIDS

By

Alex Ogwal

Infectious Diseases Institute

Definition of HIV

• Human Immunodeficiency Virus.

• Retrovirus

• Attacks the CD4-T cells weakening the immune system and finally AIDS.

What is AIDS?

• Acquired Immune Deficiency Syndrome

• Weakened immune system

• Life threatening opportunistic infections and cancers.

Epidemiology

• Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control health problems.

• The epidemiology of HIV/AIDS is the study of the determinants and distribution of HIV/AIDS in specified populations like adults, children, women or men.

Estimated numbers of adults and children in Uganda living with HIV/AIDS, end of 2003 and 2005

Number of deaths due to AIDS in Uganda

MODES OF HIV TRANSMISSION• Sexual transmission

• Injection drug use (IDU)

• Mother to child transmission of HIV– Maternal viral load – Maternal CD4 ( risk of transmission increase 3-fold if CD4 < 400) – Lack of antiviral therapy – Prolonged rupture of membranes (rate doubled if >4 hours) – Breast feeding (gives additional 10-14 % risk of transmission) – Mode of delivery - elective C-section

• Blood product transfusion

• Occupational exposure

• Donor organ or tissue transplantation with a source who had HIV

Programmes aimed at reducing sexual transmission

• Heterosexual vaginal intercourse. – change sexual behavior– reduce the number of sexual partners – safe sex techniques such as condoms

• Voluntary counseling and testing (VCT)

• Routine counseling and testing (RCT

• Counseling and control of sexual transmitted diseases (STD)

• Condom distribution and proper use

• Education about AIDS – radio, video, drama, folk media, and religion

• HAART

POST EXPOSURE PROPHYLAXIS (PEP)• The risk of HIV will depend on;

– The type of exposure• hollow needle stick injury Vs solid needle

– Volume of blood involved e.g. transfusion

– VL at the time of exposure

Principles of PEP

• Immediate care of exposed site

• Determine risk associated with the exposure

– type of fluid such as blood, quantity of fluid– type of exposure

• percutaneous injury Vs broken skin Vs mucous membrane exposure

• hollow needle with deep injury Vs solid needle with superficial injury

• Evaluate the exposure source – Initiating PEP within 24 hours of exposure – Offering pregnancy test to women of child bearing age– Seeking expert consultation if ARV resistance is suspected from the

source person – Administering PEP for the subsequent 4 weeks if tolerated.

Recommendations from the Ugandan ART treatment guidelines

Recommended HIV PEP for percutaneous injuries

Recommended HIV PEP for mucous membrane and broken skin exposure

Following up a patient on PEP

• Counsel the health worker on possible adverse events – like anemia and severe vomiting due to Combivir, – nightmares and sleep disturbance due to Efavirenz ,– pins and needles due to D-drugs (Stavudine/Didanosine)

• Provide medical evaluation and follow up the health worker to assess adverse events for 2-4 weeks

• Follow up HIV testing in months 3 and 6

• Prevent possible sexual transmission – use condoms consistently.

• Remember to report the injury to the facility in-charge or the designated PEP person.

Preventive strategies for health workers

• Routine use of barrier – gloves, eye goggles, protective clothing for

theatres and maternity units

• Washing hands and other skin surfaces immediately after contact with blood or body fluids

• Careful handling of sharp instruments during and after use; NEVER RE-CAP NEEDLES

• Safe disposal of used sharps

Provisions needed of every health facility• Using SOPs for handling of sharps at all facilities

• Clear separation of “clean” and “dirty” areas

• Sufficient supplies of gloves, needles, syringes, injection boxes

• Incineration or safe destruction of sharp devices

• Provision of care and treatment for health workers with HIV

• Provision of post Exposure Prophylaxis

TAHNK YOU VERY MUCH FOR LISTENING