Prevention and Control of AIDS for World AIDS day
Methods of transmission and control procedures for AIDS control.
Published on: Mar 4, 2016
Transcripts - Prevention and Control of AIDS for World AIDS day
Prevention and Control of AIDS
Dr Mostafa Mahmoud, MD, Ph D,
Assist. Prof. of Medical Microbiology
Where HIV present in human body fluids?
Infectious Body Fluids Non-Infectious Body Fluids
• All body fluids containing
• Pericardial fluid
• Pleural fluid
• Peritoneal fluid
• Cerebrospinal fluid (CSF).
• Amniotic fluid
• Synovial fluid
• Vaginal secretion
• Breast milk
• Nasal secretions
How can the HIV transmitted in community?
The most common modes of transmission:
• Having sex with someone who has HIV (anal sex
is the highest then, vaginal and multiple
• Sharing needles, syringes, rinse water, or other
equipment (works) used to prepare injection
drugs with someone who has HIV.
The Less common modes of transmission:
1. Being born to an infected mother (pregnancy
& breast feeding).
2. Receiving blood transfusions, blood
products, or organ/tissue transplants that
are contaminated with HIV.
3. Eating food that has been pre-chewed by an
HIV-infected person during chewing in infants
4. Being bitten by a person with HIV.
5. Oral sex
6. Deep, open-mouth kissing if the person with HIV
has sores or bleeding gums and blood is
7. Contact between broken skin, wounds, or
mucous membranes and HIV-infected blood or
blood-contaminated body fluids.
8. Tattooing not reported in USA but can happen.
Modes of transmission among HCWs
• Being stuck with an HIV-contaminated needle or
other sharp object.
• Contact between broken skin, wounds, or
mucous membranes and HIV-infected blood or
blood-contaminated body fluids.
• Air or water.
• Insects, including mosquitoes or ticks.
• Saliva, tears, or sweat or spitting.
• Casual contact like shaking hands or sharing
• Closed-mouth or “social” kissing
• Toilet seats
A. Prevention of HIV transmission in
1. There is no vaccine for preventing HIV
2. Male circumcision decrease risk to Circumcised
man but not to women (inconclusive effects for
circumcision in other situations).
3. Strict examination for blood, blood products,
organ donation for HIV before administration.
4. No sharing of needles, brushes or razors.
5. Proper sterilization of dental & surgical
6. Prevent HIV infection during anal or
• Use condoms the right way every time you
• Take medicines to prevent or treat HIV if
• Choose less risky sexual behaviors
• Get tested for other sexually transmitted
diseases (STDs) e.g. HBV, HCV, ..etc.
• Limit your number of sex partners.
7. Prevent HIV infection from oral sex
• Little to no risk of getting or transmitting HIV
from oral sex.
• Theoretically, transmission of HIV is possible
if an HIV-positive man ejaculates in his
partner’s mouth during oral sex. However,
the risk is still very low, and much lower than
with anal or vaginal sex
8. Prevent HIV infection to the baby
• By antiviral treatment of infected mother.
• Breast feeding ; stop if there is affordable
formula, and continue if not (poor countries)
with receiving antiviral treatment (WHO 2010).
9. Pre-Exposure prophylaxis
• For those who are at very high risk for HIV
from sex or injecting drugs, by taking HIV
antiviral daily. medicines daily, called pre-
exposure (or PrEP), can greatly reduce your
risk of HIV infection.
10. Prevention among drug users
• Stopping injection and other drug use can
lower your chances of getting or transmitting
HIV a lot.
• If you keep injecting drugs, use only sterile
needles and works. Never share needles or
Vaccine development is difficult due to:
1. Rapid mutation of the virus especially in the
2. HIV spread from cell to cell via a fusion
process without contacting blood containing
3. Lack of an appropriate animal model for AIDS
• High-risk settings
• Obstetric procedures
• Labour and delivery
• Immediate care of the infant
• Other blood-borne infections:
–Hepatitis B and C
–Bacterial infections like Brucellosis
Prevention of HIV Transmission in HCWs
Prevent the Transmission circuits:
• from HCWs to patient
• From Patient to HCWs
• From Patient to patient (Equipment)
by Application of the Standard Precautions.
•Patient to patient
Sterilize contaminated equipment and devices
Infection Control Measures
• Standard Precautions
• Management of the work environment
• Ongoing education of employees in all aspects
of infection prevention
–Applied universally in caring for all patients
• Hand Hygiene (HH)
• Decontamination of equipment and devices
• Use and disposal of needles and sharps
safely (no recapping)
• Wearing personal protective equipment
• Prompt cleaning up of blood and body fluid
• Systems for safe collection of waste and
Promotion of a Safe and Supportive Work
• Management of the work environment to
promote safety includes:-
• Implementation, monitoring and evaluation of
use of Standard Precautions.
• Procedures for reporting and treating
occupational exposure to HIV infection
• Maintaining and monitoring of appropriate staff
• Providing protective equipment and materials
• Providing appropriate disinfectants.
Education in Infection Prevention
• Education of HCWs includes
• Making all staff aware of established
infection control policies
• Ongoing training to build skills in safe
handling of equipment and materials
• Monitoring and evaluation of practices
to remedy deficiencies
• Soap and water hand washing using friction
under running water for at least 15 seconds
• Using alcohol-based hand rubs (or antimicrobial
soap) and water for routine decontamination
How long HIV survives in the
• Depends upon volume & type of body fluid, pH
of environement, viral Conc., and temp.:-
1. HIV remains relatively stable in blood at RT, and
may persist for at least a week in dried blood at
2. HIV may survive for up to four weeks in syringes
after HIV-infected blood has been drawn up into
the syringe and then flushed out.
3. HIV may survive in dried blood at RT for up to
five or six days in optimal pH.
4. Sewage is highly unlikely to pose a risk because
infectious HIV has never been isolated from
feces or urine.
5. HIV does not survive as long as other viruses in
6. Infectious HIV has been recovered from human
cadavers between 11 and 16 days after death
in bodies stored at the usual mortuary
temperature of 2°C.
7. No studies have investigated the survival of HIV
in semen outside the body
Disinfection and inactivation
HIV is completely inactivated by:
1. Treatment for 10 minutes at room temperature
10% household bleach
50% ethanol ,
0.5% Lysol ,
0.3% hydrogen peroxide
2. Extremes of pH
3- Heating at 56 °C for 10 minutes
4- Lyophilized blood products heated at 68 °C for
(N.B. Cold not inactivate HIV in blood even at -70 oC)
Managing Occupational Exposure to HIV
Post-Exposure Prophylaxis (PEP):
• PEP – Following occupational HIV exposure,
short-course of ARV drugs can be used to
reduce the likelihood of infection.
• Register occupational exposures.
• Ensure that HIV counselling, testing, and ARV
drugs are available.
• Educate healthcare workers.
AIGH Policy for sharp injuries & Cuts
• Policy applied to HBV, HCV & HIV.
• Needle or Sharp Injury at Working hours (8
AM to 4 PM): to IPC Dept.
• After Working hours (4 PM to 8 AM) and in
vacations (Friday & Saturday): to the ED dept.
• Procedures to be done in either departments:
1. Documenting the case and all required data as
in NSI reporting form.
2. Wash needle-sticks and cuts with soap and
3. Flush splashes to the nose, mouth, or skin with
4. Irrigate eyes with clean water, saline, or sterile
N.B.- Squeezing of the wound or the use of
antiseptics have nothing to do and not
recommend also, the use of caustic agents are
If the staff was managed at ED he must
present to the IPC Dept. in the next
working day to have done the following:-
1. Define the type, and location of the injury, and the
purpose of sharp sage.
2. After defining of the source of infection the
virological status of the source to be defined HBV,
3. If the source status is unknown and available, he or
she must be examined for these viruses (HBV, HCV,
& HIV) by the IPC staff sending samples to the lab.
- After that staff must go to the SHC for PEP
Management of staff exposed to HIV-positive source:
1. There is no vaccine for HIV however; antiviral post-
exposure therapy can prevent HIV infection. So, PEP
is recommended in certain cases.
2. Combination of Two antiviral therapy is
recommended for 4 weeks can be modified on a
3. If the source is unknown virological status, follow
up must be done for 6 months.
4. PE treatment must started within hours in exposure
to positive source (delay for 24-36 hours is less
effective in preventing HIV infection).
5. The FDA did not approve drug treatment for HIV
PEP but only for treating exiting infection.
6. HIV antiviral agents have many side effects and
the benefits of administration must be balanced
against the possibility of getting infected in
routine cases and also in pregnancy.
7. Follow up for 6 months after exposure is
important and for drug toxicity if receiving
8. Post-exposure precautions for 6-12 weeks in
HIV include; no blood donation, no organ
donation, no sexual intercourse (or use of
condoms), no breast-feeding !!.
PEP after exposure to HBV-positive:
1. HBV infection have an effective vaccine and PEP by
hepatitis B immunoglobulin (HBIG).
2. If the staff is not vaccinated, the staff must receive
HBIG injection as early as possible within 24 hours
of exposure and not more than 7 days after
3. Start HBV vaccination at once for 3 successive
doses for non-vaccinated staff regardless the
source is positive or negative for HBV at (0, 1 and 6
months) with measurement of the HBsAb Titer
after one month to test for immunization (> 10
4. If the staff is vaccinated then give booster dose of
the vaccine and no need for HBIG.
4. Both HBV vaccine and HBIG are safe and FDA
5. Both HBV vaccine and HBIG are safe to be given
to pregnant females.
6. No follow up is needed after treatment and
vaccination against HBV is required.
7. No special precautions are required after
exposure to HBV positive and receiving
8. If the virological status of the source is unknown,
then manage the exposed staff as positive
exposure and start vaccination.
PEP after exposure to HCV-positive:
1. Neither effective vaccine nor PE treatment
preventing HCV infection is available.
2. Neither immunoglobulin nor antiviral therapy
is recommended after exposure.
3. Prevention of the exposure the cornerstone of
management and is imperative.
4. Follow up by HCV Ab testing and liver enzymes
(ALT) must be done for 6 months after
exposure to HCV positive or Unknown status.
5. For earlier detection of infection it is advised
to test for HCV RNA by PCR 4-6 weeks after
6. No special precautions after exposure to HCV
positive case are required as the risk of
becoming infected or transmit the infection
to others are very low.
• Abdala N et al. Survival of HIV-1 in syringes. J Acquir
Immune Defic Syndr Hum Retrovirol 20(1):73-80, 1999.
• Voeller B Heterosexual transmission of HIV. JAMA
• Advisory Committee on Dangerous Pathogens HIV - the
causative agent of AIDS and related conditions. Department
of Health, 1990
• Slade JS et al. The survival of human immunodeficiency
virus in water, sewage and sea water. Water Science and
Technology 21(3): 55-59, 1989.