Leon is an African American community activist in one of this countrys largest cities. His role has made him very visible and the public watches his every move. When Leon was diagnosed with H

Transmission and Prevention of HIV Infections

I. Transmission A. HIV is transmitted through:

1. Sexual contact (both heterosexual and homosexual intercourse) 2. Blood to blood contact 3. Mother to child

B. Sexual Contact 1. Most common mode of transmission. 2. About 90% of all HIV infections worldwide happen through sex. 3. Sexual contact involves the exchange of semen (sperm), vaginal fluids or blood. 4. The HIV virus is also found in menstrual blood.

C. Oral Sex 1. Different studies have reported different levels of risk ranging from less than 1

percent to about 8 percent. 2. It is difficult to determine the exact level of risk of being infected by oral sex

because: a. It can be difficult to get accurate information from patients. b. Most people don’t just have oral sex so it is difficult to single out oral sex

as the definitive way HIV was transmitted. 3. The risk of infection via oral sex is higher for:

a. People who have gum disease or oral ulcers. b. People who engage in oral sex that includes ejaculation. c. Therefore, although the risk is small, the possibility of contracting HIV

through oral sex does exist. D. Blood to Blood Contact

1. Intravenously—use of contaminated needles, accidental needle sticks, particularly among healthcare workers.

2. Through the use of HIV contaminated skin-piercing instruments (ex. ears, acupuncture and tattoos).

3. Contaminated blood products (ex. blood transfusion). E. Mother to Child

1. In utero- in the womb (HIV can cross the placenta) 2. Intrapartum-during delivery 3. Postpartum-via breast milk

II. HIV is not transmitted through A. Toilet seats B. Air C. Water D. Drinking glasses E. Sneezing F. Casual contact G. Clothing H. Insects

1. Studies by the CDC and elsewhere have shown no evidence of HIV transmission through insects.

Transmission and Prevention of HIV Infections

2. Experiments and observations of biting activity by insects indicate that when an insect bites a person, it does not inject its own or a previously bitten person’s or animal’s blood into the next person bitten.

3. Rather, it injects saliva, which acts as a lubricant or anticoagulant so the insect can feed efficiently.

4. Diseases such as yellow fever and malaria are transmitted through the saliva of certain species of mosquitoes.

5. However, HIV lives for only a short time inside an insect and does not reproduce (and does not survive) in insects.

6. Therefore, even if the virus enters a mosquito or another sucking or biting insect, the insect does not become infected and cannot transmit HIV.

III. HIV might be transmitted through: A. Kissing/Saliva

1. Casual contact through closed-mouth or "social" kissing is not a risk for transmission of HIV.

2. However, because of the potential for contact with blood during "French" or open-mouth kissing, CDC recommends against engaging in this activity with a person known to be infected with HIV.

3. The risk of acquiring HIV during open-mouth kissing is believed to be very low. 4. The CDC has investigated only one case of HIV infection that may be attributed

to contact with blood during open-mouth kissing. B. Sweat C. Lung fluid D. Cerebrospinal fluid E. Urine

IV. Patterns of Transmission A. Male to Male Transmission

1. There has been an increase in this method of transmission after many years of decline.

2. Why? Because of unsafe sexual practices 3. The highest risk sexual practice among gay men: Receptive anal sex with

ejaculation and no condom. B. Needle Sharing

1. Those who inject drugs intravenously and share needles. 2. This pattern of transmission is most prevalent in the U.S., Eastern Europe

(Russia) and Asia (China, Indonesia). C. Heterosexual Sexual Transmission

1. Most common pattern of transmission in Africa, Latin America and the United States.

2. The greatest risk is with receptive vaginal or anal intercourse, which means that women are at greater risk for sexual transmission of HIV.

Transmission and Prevention of HIV Infections

D. Other Risks 1. Anal sex is riskier than vaginal sex. 2. Although the risk with oral sex is low, there is now data to suggest that it may

account for some cases of transmissions, particularly in sex between men. 3. Other risky sexual practices:

a. Sharing sex toys b. Anal or vaginal fisting c. Mutual masturbation with external or internal touching

V. Factors that Affect Transmission A. Disease Progression

2. Individuals newly infected with HIV infection and those with more advanced disease or AIDS are more infectious because they have higher levels of virus in their blood and genital secretions.

B. Antiretroviral Treatment 1. ARV therapy lowers the amount of virus in an infected individual and therefore reduces the risk of transmission.

C. Sexually Transmitted Diseases 1. The presence of STDs increases both infectiousness and susceptibility to HIV by approximately 2 to5 times.

D. Circumcision 1. Uncircumcised men appear to be at increased risk of transmitting and acquiring

HIV. According to the CDC, this may be because: a. The foreskin of the penis is more susceptible to HIV infection. b. The inner mucosa of the penis may have a higher density of target cells

for the virus to infect. c. The foreskin may have greater susceptibility to traumatic tears during

intercourse, providing a portal of entry for pathogens, including HIV. E. Use of condoms

1. Provide the greatest protection against both transmission and acquisition of HIV.

VI. Precautions for Health Care Workers A. Both standard and universal precautions apply when working with HIV patients. B. Standard precautions

1. Precautions that are to be used with all patients, regardless of their known or suspected infection status.

2. Ex. Washing of hands, changing gloves between procedures/patients, proper disposal or of used needles.

C. Universal Precautions 1. Precautions to be used for patients known (or suspected) to be infected with

highly transmissible pathogens that can be transmitted through air, droplets or direct-contact routes. 2. They are not recommended for situations where casual contact only is involved (ex. talking with patient.) 3.

3. Universal precautions apply to blood, other body fluids containing visible blood,

Transmission and Prevention of HIV Infections

semen, and vaginal secretions. 4. They apply to tissues and to the following fluids: cerebrospinal, pericardial, and amniotic fluids.

VII. Universal Precautions for Reducing Transmission of HIV A. Using protective barriers such as gloves, gowns, aprons, masks, or protective eyewear can reduce the risk of exposure of the health care worker's skin or mucous membranes to potentially infectious materials. B. Health care workers should also take precautions to prevent injuries caused by needles, scalpels, and other sharp instruments or devices.

VIII. Reducing Transmission in Businesses and Other Settings A. Food Service Workers 1. Food-service workers known to be infected with HIV need not be restricted from work unless they have other infections or illnesses (such as diarrhea or hepatitis A) for which any food-service worker, regardless of HIV infection status, should be restricted.

2. The CDC recommends that all food-service workers follow recommended standards and practices of good personal hygiene and food sanitation. B. Personal Service Workers

1. Ex. Hairdressers, barbers, cosmetologists, massage therapists 2. In 1985, the CDC issued routine standard precautions for all personal-service workers. 3. Instruments that are intended to penetrate the skin (such as tattooing and acupuncture needles, ear piercing devices) should be used once and disposed of or thoroughly cleaned and sterilized. 4. Use of the same cleaning procedures that are recommended for health care institutions.

5. CDC knows of no instances of HIV transmission through tattooing or body piercing, although Hepatitis B virus has been transmitted during some of these practices. 6. One case of HIV transmission from acupuncture has been documented.

IX. Condoms A. Condoms are classified as medical devices and are regulated by the Food and Drug Administration (FDA). B. Only latex or polyurethane condoms provide a highly effective barrier to HIV. C. Condoms made out of natural membranes (ex. lambskin, sheepskin) may contain natural pores and have been shown to allow the passing of virus. D. Therefore, natural membrane condoms are not recommended as protection against the transmission of HIV.

1

Transmission and Prevention of HIV

Infection

2

Transmission

HIV is transmitted through:

• Sexual contact (both heterosexual and homosexual intercourse)

• Blood to blood contact

• Mother to child

3

Sexual Contact

• Most common mode of transmission.

• About 90% of all HIV infections worldwide happen through sex.

• Exchange of semen (sperm), vaginal fluids or blood.

• The HIV virus is also found in menstrual blood.

4

What About Oral Sex?

• Different studies have reported different levels of risk ranging from less than 1 percent to about 8 percent.

• It is difficult to determine the exact level of risk of being infected by oral sex because: – It can be difficult to get accurate

information from patients. – Most people don’t just have oral sex so it is

difficult to single out oral sex as the definitive way HIV was transmitted.

5

What About Oral Sex (cont’d)

• The risk of infection via oral sex is higher for: – People who have gum disease or oral

ulcers. – People who engage in oral sex that

includes ejaculation.

• Therefore, although the risk is small, the possibility of contracting HIV through oral sex does exist.

6

Blood to Blood Contact

• Intravenously—use of contaminated needles, accidental needle sticks, particularly among healthcare workers.

• Through the use of HIV contaminated skin-piercing instruments (ex. ears, acupuncture and tattoos).

• Contaminated blood products (ex. blood transfusion).

7

Mother to Child

• In utero- in the womb (HIV can cross the placenta).

• Intrapartum-during delivery (Baby may come into contact with HIV infected vaginal secretions and mucus).

• Postpartum-via breast milk. Breast milk is known to carry the HIV virus.

8

HIV Is Not Transmitted through:

o Toilet seats o Air o Water o Drinking glasses o Sneezing o Casual contact o Clothing o Insects*

9

Insects • Studies by the CDC and elsewhere

have shown no evidence of HIV transmission through insects.

• Experiments and observations of biting activity by insects indicate that when an insect bites a person, it does not inject its own or a previously bitten person’s or animal’s blood into the next person bitten.

• Rather, it injects saliva, which acts as a lubricant or anticoagulant so the insect can feed efficiently.

10

Insects (cont’d)

• Diseases such as yellow fever and malaria are transmitted through the saliva of certain species of mosquitoes.

• However, HIV lives for only a short time inside an insect and does not reproduce (and does not survive) in insects.

• Therefore, even if the virus enters a mosquito or another sucking or biting insect, the insect does not become infected and cannot transmit HIV.

11

HIV Might Be Transmitted Through

o Tears oHIV has been found in saliva and

tears in very low quantities from some AIDS patients.

oIt is important to understand that finding a small amount of HIV in a body fluid does not necessarily mean that HIV can be transmitted by that body fluid.

12

Kissing/Saliva

o Kissing/Saliva • Casual contact through closed-

mouth or "social" kissing is not a risk for transmission of HIV.

• Because of the potential for contact with blood during "French" or open-mouth kissing, CDC recommends against engaging in this activity with a person known to be infected with HIV.

13

Kissing/Saliva (cont’d)

• The risk of acquiring HIV during open-mouth kissing is believed to be very low.

• The CDC has investigated only one case of HIV infection that may be attributed to contact with blood during open-mouth kissing.

14

HIV Might Be Transmitted Through (cont’d)

o Sweat

o Lung fluid

o Cerebrospinal fluid

o Urine

15

Patterns of Transmission

• Male to Male Transmission • There has been an increase in this

method of transmission after many years of decline.

• Why? – Unsafe sexual practices

• Highest risk sexual practice among gay men: Receptive anal sex with ejaculation and no condom.

16

Patterns of Transmission (cont’d)

• Needle Sharing • Those who inject drugs

intravenously and share needles. • This pattern of transmission is

most prevalent in the U.S., Eastern Europe (Russia) and Asia (China, Indonesia).

17

Patterns of Transmission (cont’d)

• Heterosexual Sexual Transmission –Most common pattern of

transmission in Africa, Latin America and the United States.

–The greatest risk is with receptive vaginal or anal intercourse, which means that women are at greater risk for sexual transmission of HIV.

18

Other Risks

– Anal sex is riskier than vaginal sex. – Although the risk with oral sex is low, there

is now data to suggest that it may account for some cases of transmissions, particularly in sex between men.

– Other risky sexual practices: – Sharing sex toys – Anal or vaginal fisting – Mutual masturbation with external or

internal touching

19

Factors that Affect Transmission

• Disease Progression – Individuals newly infected with HIV

infection and those with more advanced disease or AIDS are more infectious because they have higher levels of virus in their blood and genital secretions.

• Antiretroviral Treatment – ARV therapy lowers the amount of

virus in an infected individual and therefore reduces the risk of transmission.

20

Factors that Affect Transmission (cont’d)

• Sexually Transmitted Diseases – The presence of STDs increases both

infectiousness and susceptibility to HIV by approximately 2 to5 times.

• Circumcision – Uncircumcised men appear to be at

increased risk of transmitting and acquiring HIV.

21

Factors that Affect Transmission (cont’d)

• Use of condoms –Provide the greatest protection

against both transmission and acquisition of HIV.

22

Precautions for Health Care Workers

• Both standard and universal precautions apply when working with HIV patients.

• Standard precautions – Precautions that are to be used with all

patients, regardless of their known or suspected infection status.

– Ex. Washing of hands, changing gloves between procedures/patients, proper disposal of used needles.

23

Universal Precautions

• Universal precautions –Precautions to be used for patients

known (or suspected) to be infected with highly transmissible pathogens that can be transmitted through air, droplets or direct-contact routes.

–They are not recommended for situations where casual contact only is involved (ex. talking with patient.)

24

Universal Precautions (cont’d)

• Universal precautions apply to blood, other body fluids containing visible blood, semen, and vaginal secretions.

• They apply to tissues and to the following fluids: cerebrospinal, pericardial, and amniotic fluids.

25

Universal Precautions for Reducing Transmission of HIV

• Using protective barriers such as gloves, gowns, aprons, masks, or protective eyewear can reduce the risk of exposure of the health care worker's skin or mucous membranes to potentially infectious materials.

• Health care workers should also take precautions to prevent injuries caused by needles, scalpels, and other sharp instruments or devices.

26

Reducing Transmission in Businesses and Other Settings

• Food Service Workers • Food-service workers known to be infected

with HIV need not be restricted from work unless they have other infections or illnesses (such as diarrhea or hepatitis A) for which any food-service worker, regardless of HIV infection status, should be restricted.

• The CDC recommends that all food-service workers follow recommended standards and practices of good personal hygiene and food sanitation.

27

Reducing Transmission in Businesses and Other Settings (cont’d)

• Personal Service Workers • Ex. Hairdressers, barbers, cosmetologists,

massage therapists • In 1985, the CDC issued routine standard

precautions for all personal-service workers. • Instruments that are intended to penetrate the

skin (such as tattooing and acupuncture needles, ear piercing devices) should be used once and disposed of or thoroughly cleaned and sterilized.

28

Reducing Transmission in Businesses and Other Settings (cont’d)

• Instruments not intended to penetrate the skin but which may become contaminated with blood (ex. razors) should be used for only one client and disposed of or thoroughly cleaned and disinfected after each use.

29

Personal Care Workers (cont’d)

• Use of the same cleaning procedures that are recommended for health care institutions.

• CDC knows of no instances of HIV transmission through tattooing or body piercing, although Hepatitis B virus has been transmitted during some of these practices.

• One case of HIV transmission from acupuncture has been documented.

30

Condoms  Condoms are classified as medical devices

and are regulated by the Food and Drug Administration (FDA).

 Only latex or polyurethane condoms provide a highly effective barrier to HIV.

 Condoms made out of natural membranes (ex. lambskin, sheepskin) may contain natural pores and have been shown to allow the passing of virus.

 Therefore, natural membrane condoms are not recommended as protection against the transmission of HIV.