Queensland Health Resources > Sexual Health

Sexual Health - Post Exposure Prophylaxis for Non-Occupational Exposure to HIV and HBV

Rationale

Procedure

Risk of transmission following exposure to HIV infected person

Expert information network

References

In June 2000 Queensland Health developed guidelines for the management of non-occupational exposure to HIV and HBV. Post-exposure prophylaxis is now available to persons assessed to be at risk of HIV and/or HBV infection through non-occupational exposure. HIV post exposure prophylaxis can be accessed through S100 (HIV) prescribers, sexual health clinics and public hospitals
View the Post Exposure Prophylaxis (PEP) fact sheet.

Rationale

The most effective means of preventing human immunodeficiency virus (HIV) infection and hepatitis B (HBV) infection continues to be those methods that protect against exposure. They include preventative behaviours such as sexual abstinence or adherence to safe sex practices (including consistent and correct condom use), and abstinence from injecting drug use or adherence to safe injecting practices (including consistent use of sterile injecting equipment) and hepatitis B vaccination
HIV post exposure prophylaxis has been available for some time for occupational exposures among health care workers in Queensland. However, more than 90 percent of HIV transmission episodes in Australia occur in non occupational settings through sexual activity and up to five per cent through injecting drug use. The risks of transmission associated with unprotected intercourse and needle sharing in discordant couples have been estimated to be at least as high as the risks of transmission in occupational exposures
It is believed that PEP after sexual or non occupational needle-stick exposure to HIV may prevent HIV infection in a manner similar to that in the occupational setting. In the first year of a NSW study initiated to monitor implementation of their guidelines, there have been no seroconversions among 61 individuals followed up for four weeks and 28 followed up for six months
HBV post exposure prophylaxis is also available for occupational exposures among health care workers in Queensland. Passive immunisation with hepatitis B immunoglobulin (HBIG) following significant percutaneous or mucosal exposure to blood and sexual exposure, where the source is hepatitis B surface antigen (HbsAg) positive has been shown to prevent hepatitis B virus (HBV) infection. It is feasible that PEP after non occupational exposure to HBV will prevent HBV in a manner similar to that in the occupational setting
Public health messages must continue to emphasise primary prevention methods as the first line of protection against exposure to blood borne and sexually transmissible infections. Individuals who present for non occupational PEP are in contact with health care providers at a time when they have been at risk of HIV infection. This should be taken as an opportunity to target prevention strategies to people at a time when they are most at risk
There is now evidence that in this situation, individuals who have been at risk are more likely to practice safe sex as a result of the interaction
Knowledge regarding treatment of exposure to HIV and HBV is evolving rapidly. Therefore, in addition to the guidelines below, the advice of an appropriate medical specialist should always be sought prior to commencement of treatment.

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Procedure

1. Immediate care of the exposed person

After exposure to blood or other body fluids the person should as soon as possible do the following:

Encourage bleeding if the exposure involves a cut or puncture, then wash with soap and water
Wash with soap and water where the exposure does not involve a cut or puncture, except in cases of unprotected anal or vaginal intercourse, including condom breakage, where douching should be discouraged
If eyes are contaminated then rinse them, while they are open, gently but thoroughly (for at least 30 seconds) with water or normal saline
If blood or other body fluids get in the mouth, spit them out and then rinse the mouth with water several times
If clothing is contaminated, remove clothing and shower if necessary
Inform an appropriate person to ensure that necessary further action is undertaken
Dispose adequately of any sharps or other equipment responsible for the incident
Where water is not available, use of a non-water cleanser or antiseptic should replace the use of soap and water for washing cuts or punctures of the skin or intact skin.

2. Risk Assessment

The exposure:

The factors which should be considered include:

* The type of sexual activity which was involved
* Intoxication or substance use
* The type of sharing of injecting equipment which was involved
* The nature and extent of the injury, where an injury is involved
* The nature of the item that caused the injury, where an injury is involved eg. gauge of the needle
* The nature of the body fluid involved
* The volume of blood and body fluids to which the person was exposed
If the exposure was percutaneous or involved exposure of mucous membranes or non-intact skin to potentially infective fluids, the exposed person should be assessed further as set out below
Otherwise, no further testing or examination is required apart from the possibility of further counselling. This should be determined according to individual circumstances
The source
* To adequately assess risk it is important to try to ascertain the HIV and/or HBV status of the source
If the status of the source individual is unknown at the time of the exposure, then baseline testing should be undertaken to determine the sources infectious status for HIV or HBV, by testing for HIV antibody, and/or HbsAg
Testing of the source individual must follow accepted guidelines. Pre and post test counselling must be given and informed consent obtained before testing can proceed
Confidentiality is to be maintained, not only of the source of infection, but also regarding the current exposure or injury
If the source is infected with HIV or HBV and is not already in the care of an appropriate medical specialist, then they should be referred to such a specialist
The exposed person
* The exposed person should be offered the opportunity of ascertaining their baseline HIV, HBV and HCV status with appropriate pre and post test counselling and consent
Storage of serum for later testing can be requested if immediate testing is declined
Consider screening or treatment for other sexually transmissible infections
Consider risk of pregnancy and discuss emergency contraception as appropriate.

3. Treatment of the exposed person

Source negative for HIV and HBV:
* Apart from counselling and collecting blood from the exposed person, no further action is required in relation to HIV or HBV
Source unknown or unable to be tested:
* If there are factors which indicate a high risk of the source being infected with HIV and/or HBV, then the exposed person should be managed as set out as below
Source positive for HIV or likely to be positive:
* Initiation of HIV prophylaxis depends on the type of exposure. Information concerning the source’s stage of HIV infection, viral load and history of HIV therapy should be ascertained so that appropriate therapy and counselling can be offered. The risk of transmission following exposure to a HIV infected partner is detailed in the Table following. It is important to note that studies of the risk of transmission have employed different methodologies and are difficult to compare, but all include estimates of risk which are of the same order of magnitude. In addition, other factors such as intercurrent genital infections and ulceration of both the donor and the recipient influence the risk of transmission. Heterosexual transmission studies are generally based on long term relationships and repeated exposure to the same infected individual rather than a one-off exposure
* The epidemiological data do not support transmission of HIV via oral sexual activity - however there have been case reports which suggest HIV infection following oral-genital sex.

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Risk of transmission following exposure to HIV infected person

Type of Exposure	Estimated Risk of HIV Transmission (per Episode)
Receptive anal intercourse	0.1%-3%
Use of contaminated injecting equipment	0.67%
Needle stick injury of HCW	0.4%-0.8%
Receptive vaginal intercourse	0.1%-0.2%
Insertive vaginal intercourse	0.03%-0.09%
Insertive anal intercourse	No published per-contact estimates of risk, but estimated to be at least as high as for insertive vaginal intercourse

The exposed person should be informed (both on presentation and within a few days at follow-up) of the potential risk of HIV transmission to sexual and injecting partners, especially during the first 6 to 12 weeks following exposure to an HIV infected partner. During this period the exposed person should be advised:
* Not to donate plasma, blood, body tissue, breast milk or sperm
* To protect sexual partners through abstaining from sexual activity or by adopting safe sexual practices (use of condoms etc)
* Not to share any injecting equipment, if involved in injecting drug use
* T o seek expert medical advice regarding pregnancy and/or breastfeeding
Seek specialist advice regarding commencement of post exposure prophylaxis
If prophylaxis is to be given it should be commenced as soon as possible following exposure, preferably within one to two hours and certainly within 24 to 72 hours of exposure. Prophylaxis is probably most effective if administered within 72 hours of exposure. Beyond this time, it is unlikely to be helpful
Regimes used as post exposure prophylaxis for HIV generally include at least two antiretroviral drugs taken for one month. Current Queensland recommendations include a combination of three antiretroviral drugs: lamivudine, zidovudine and nelfinavir
Counselling of the person who is considering prophylaxis should include information on:
* Appropriate referral for support
* Ongoing need for safe sexual and injecting practices
* The risk of HIV infection following the exposure
* The reports of seroconversion following HIV prophylaxis
* The side effects and adverse reactions associated with HIV prophylaxis
* The use in pregnancy / breastfeeding of HIV prophylaxis (if appropriate)
* The current status of knowledge regarding the efficacy of prophylaxis following exposure
* To HIV
* The risk of infecting others
The decision to accept or decline treatment is that of the exposed person, and should be documented
The exposed person should be retested at six weeks and three months. If antiviral therapy is given, testing for HIV antibody should be continued to six months following the exposure, as therapy may delay conversion to seropositive status
Source positive for HBV or likely to be positive:
* In a source known to be HBsAg positive, testing of the exposed person for HIV, HBV and HCV antibodies and for other STIs should be undertaken with appropriate pre and post test counselling and consent. Storage of serum for baseline testing can be requested. If the source is not already in the care of a medical specialist in HBV, then they should be referred to such a specialist
The exposed person should be informed (both on presentation and within a few days at follow-up), that there is overwhelming evidence that HBV is sexually transmitted and that the risk of transmission following exposure to the blood of an infected person ranges from one to six per cent for e antigen negative blood to 22 to 40 per cent for e antigen positive blood and/or HBV DNA positivity especially during the first six months following the incident. During this period the exposed person should be advised:
* N ot to donate plasma, blood, body tissue, breast milk or sperm
* T o protect sexual partners by abstaining from sexual activity or by adopting safe sexual practices (use of condoms etc)
* N ot to share any injecting equipment, if involved in injecting drug use
* T o seek expert medical advice regarding pregnancy and/or breastfeeding
If there is evidence of acute hepatitis, then the exposed person should be referred to a specialist experienced in the management of HBV
Counselling of the exposed person should include information on:
* A ppropriate referral for support
* O ngoing need for safe sexual and injecting practices
* T he risk of HBV infection following exposure
* T he side effects and adverse reactions associated with HBV vaccination and HBIG
* T he use in pregnancy/breastfeeding of HBV vaccination and HBIG
* T he risk of infecting others
The decision to accept or decline treatment is that of the exposed person, and should be documented
The exposed person should have baseline testing for HBsAg, be retested at six weeks, three months and six months; and be offered testing for other blood borne viruses and sexually transmitted diseases
Management of exposed persons where the source is positive or likely to be positive for HbsAg
The efficacy of HBIG is markedly reduced if administered after 72 hours following percutaneous exposure.

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Exposed person

Source is HBsAg positive

Unimmunised

Sexual exposure
HBIG within 14 days

Percutaneous exposures
HBIG within 24 hours, if possible

Hepatitis B immunisation should be commenced if the exposed person is at continued risk of exposure to HBV

Previously immunised: anti-HBs titre known or available within 48 hours for percutaneous exposure or 14 days for sexual exposure

Titre <10mIU/mL
Sexual exposure
HBIG within 14 days; and again at 4 weeks
Percutaneous exposures
HBIG within 24 hours, if possible; and again at 4 weeks

Titre 10-99mIU/mL
Hepatitis B vaccine booster dose

Titre >=100mIU/mL
No treatment

Previously immunised but anti-HBs titre not known and not available within 48 hours for percutaneous exposure or 14 days for sexual exposure

Sexual exposure
HBIG within 14 days; and again at 4 weeks

Percutaneous exposure
HBIG within 24 hours, if possible; and again at 4 weeks
Once available, if anti-HBs <100mlU/mL, hepatitis B vaccine booster dose

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Expert information network

Advice will be provided 24 hours a day, seven days a week by the infectious diseases physician on call. They can be contacted through the switchboard in the following facilities:

Brisbane
Princess Alexandra Hospital (07) 3240 2111
Mater Adult Hospital (07) 3840 8111
Royal Brisbane Hospital (07) 3636 8111
Gold Coast
Gold Coast Hospital (07) 5571 8211
Nambour
Nambour General Hospital (07) 5470 6600
Townsville
Townsville General Hospital (07) 4781 9211
Cairns
Cairns Base Hospital (07) 4050 6333
In addition, during working hours, advice may be sought from sexual health physicians at sexual health clinics as listed below.

Sexual Health Clinic	Telephone
Brisbane City	(07) 3227 8666
AIDS Medical Unit	(07) 3224 5526
Brisbane South	(07) 3240 5881
Cairns	(07) 4050 6205
Gold Coast	(07) 5576 9033
Ipswich	(07) 3817 2428
Logan	(07) 3240 5881
Mackay	(07) 4968 3881
Mt Isa	(07) 4744 4805
Nambour	(07) 5476 2489
Redcliffe/Caboolture	(07) 5433 8300
Rockhampton	(07) 5479 2670
Sunshine Coast	(07) 5479 2670
Thursday Island	(07) 4069 0413
Toowoomba	(07) 4631 6446
Townsville	(07) 4778 9600
Wide Bay	(07) 4197 7260

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References

ANCARD HIV/AIDS Clinical Trials and Treatments Advisory Committee. Antiretroviral Therapy for HIV Infection: Principles of Use. Standard of Care Guidelines. October 1997

CDC Update: Provisional Public Health Service Recommendations for Chemoprophylaxis After Occupational Exposure to HIV. MMWR 1996; 468-80

CDC (1995). Case Control Study of HIV Seroconversion in Health Care Workers After Percutaneous Exposure to HIV Infected Blood – France, United Kingdom and United States, January 1988-August 1994. Morbidity and Mortality Weekly Report, 44, 929-33.

CDC (1998). Public Health Service Guidelines for the management of health-care worker exposures to HIV and recommendations for postexposure prophylaxis. Morbidity and Mortality Weekly Report, 47 (no RR-7), 1-39

CDC. Management of possible sexual, injecting drug use, or other non occupational exposure to HIB, including considerations related to antiretroviral therapy. Public Health Service Statement. MMWR 1998;47 (no RR-17)

Connor, E.M., Sperling, R.S., Gelber, R., et al. Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. The New England Journal of Medicine 1994; 331: 1173-1180

Guay, L.A., Musoke, P., Fleming, T., et al. Intrapartum and neonatal single-dose nevirapine compared with zidovudine for prevention of mother-to-child transmission of HIB-1 in Kampala, Uganda: HIVNET 012 randomised trial. Lancet 1999; 354:795-802

Holmes, K.K., Mardh, P.A., Sparling, P.F., Weisner, P.J. (editors). Sexually Transmitted Diseases. Second Edition. McGraw Hill. New York. 1990

Katz, M.H., & Gerberding, J.L. (1997). Post-exposure treatment of people exposed to the human immunodeficiency virus through sexual contact or injection drug use. New England Journal of Medicine, 336, 1097-1100.

Katz, M.H., Gerberding, J.L. The Care of Persons with recent Sexual Exposure to HIB. Ann Intern Med 1998; 128:306-312

Mastro, T.D., de Vincenzi, I. Probabilities of sexual HIV 1 transmission. AIDS 1996; Vol 10, Supplement A: 575-582

Mijch, A. ASHM Discussion Paper on Post Exposure Prophylaxis (PEP) in individuals exposed to HIV via sexual exposure or injecting drug use. Noah’s Arc 1998;9 (2)

National Centre in HIV Epidemiology and Clinical Research (editors) (1999). HIV/AIDS, hepatitis C and sexually transmissible infections in Australia: Annual surveillance report 1999.

National Centre in HIV Epidemiology and Clinical Research, Post exposure prophylaxis for non-occupational exposure to HIV: Experience in New South Wales one year after the guidelines, February 2000

Queensland Health, Infection Control Guidelines June 1999. See http://www.health.qld.gov.au/chrisp/ic_guidelines/contents.asp

Sepkowitz, K.A. Occupationally acquired infections in health care workers. Annals Internal Medicine. 1996;125:917-928

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Last Updated: 13 December 2007
Last Reviewed: 13 December 2008