HIV routes of transmission n Contaminated blood products

HIV – routes of transmission n Contaminated blood products n Sexual intercourse n Mother- to- child (vertical route)

HIV – routes of transmission Contaminated blood products -blood transfusion -skin penetrating procedures -contact of contaminated body fluid with mucose membrane or non intact skin

Risk of HIV transmission after single exposure to contaminated blood n Percutaneus - needlestick in HCW - sharing needles by IDU n n n Mucous membranes Non-intact skin (several cases reported) 0, 32% 0, 67% 0, 09% lower risk Exposure to other contaminated fluids still lower risk

Circumstances increasing the risk of transmission n Deep penetration n Blood visible on the tool 5, 2% Needle just withdrawn from the vein 5, 1% End-stage AIDS 6, 4% n n 16, 1% Applying retrovir in post exposure prophylaxis decreases the risk by 80%

HIV – routes of transmission Sexual intercourse Risk about 0, 5 %

Risk of pathogen transmission resulting from a single sexual contact with infected person HIV Gonorrhea 0, 5% 22 -25%

HIV – routes of transmission Mother–to-child transmission (vertical transmission) Frequency 25 -30% ( in Africa 40% )

Vertical transmission of HIV n n Transmission rate is related to HIV infection stage and viral load in the mother Main routes: - delivery - breastfeeding - transplacental

Infectious body fluids in HIV positive individual n n n n n Blood and its derivates Seminal fluid Discharge from genital tract - vaginal exsudate - cervical mucus Human milk Cerebro-spinal fluid Synovial fluid, amniotic fluid, pericardial fluid, pleural fluid, peritoneal fluid. Any fluid contaminated with blood Samples of tissues, transplants Concentrate of virus used in research laboratories

Non-infectious body fluids in HIV positive individual Saliva Tears Sputum Sweat Urine Feces

To obtain an infective dose of HIV virus in saliva it would be necessary to swallow 0, 5 l of this fluid

How you cannot acquire HIV n n n n n Handshake Friendly kiss Drinking from the same glass Sharing plates, spoons, forks, knifes Wearing the same clothes Sharing bathtube, toilet Sleeping in the same bed (sex excluded) Bathing in the swimming pool Bites of the insects

USA, 1990 757 household contacts of HIV positive patients have been checked. No case of virus transmission has been found. (Typical routes of transmission have been excluded)

HIV – routes of transmission Risk groups– risky behaviours