JEFF MANN'S EM GUIDEMAPS - BLOOD EXPOSURE
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Introduction

Occupational post exposure HIV prophylaxis

Non-occupational post exposure HIV prophylaxis

Hepatitis B

Hepatitis C

Appendix

Recommended review journal articles and web-based educational resources

Commentary, criticism and controversy

Introduction

- this guidemap is mainly focused on the ED management of occupational blood and body fluid exposures with a lesser emphasis on non-occupational exposures

- this guidemap represents the author's attempt to develop a rational approach to the problem of post exposure HIV prophylaxis, and this guidemap also offers some simple advice on how to deal with the risk of hepatitis B and/or hepatitis C following blood or body fluid exposure

- this guidemap should not be regarded as the "standard of care" - it's merely a distillation of the best review articles that I could find on the subject - and the reader should comply with local hospital protocols and only use this guidemap as a supplementary educational/informational resource

- this guidemap will be frequently revised if the author acquires more accurate (evidence-based) knowledge from expert-opinion journal articles, revised CDC protocols and/or constructive criticism from readers

Occupational post-exposure HIV prophylaxis

- when a health care worker (HCW) presents to the ED following an occupational exposure to blood or other body fluids, the ED should use a pre-planned post exposure protocol that will expedite management - speed is of the essence because HIV prophylactic therapy should optimally be started within 1 - 2 hours of exposure for maximum prophylactic efficacy

(there is some evidence to demonstrate that the prophylactic efficacy of anti-retroviral therapy progressively decreases with time - it is unlikely that any benefit will be obtained if therapy is instituted > 72 hours after exposure, although HIV prophylactic therapy can even be given up to ~ 2 weeks post exposure)

- because expeditious managment requires a significant amount of data collection, computerised check-off forms may allow for more rapid and more complete information retrieval

- a computerized charting system should optimally include clinical guidelines, treatment protocols, a written information package that can be given to the exposed person, a follow-up plan and a means of documenting the provision of after-care instructions

History of the exposure

- first obtain detailed information about the exposure

- determine whether the source patient is known to be HIV positive - determine whether the health care worker Diagnostic testing

- baseline testing of the HCW includes testing for:-

(female HCW's in the reproductive age group should also have a serum HCG ordered)

- a blood glucose is recommended if the HCW is to be treated with protease inhibitor drug, which may produce or aggravate hyperglycemia and an urinalysis if indinavir is to be used

 - the source patient's blood should be tested for:-

- routine testing of a HIV-seronegative source patient's blood for HIV RNA or p24 antigen to detect early infection (prior to the detection of any HIV antibody) is not routinely recommended

- performing HIV testing on any dried body fluid sample or dirty needle is not recommended - because the results obtained are not reliable and the results will not influence immediate decision-making

- all positive rapid HIV antibody tests should be confirmed by highly specific laboratory testing procedures, although PEP therapy should not be delayed if the source patient's rapid HIV antibody blood test is positive

Indications for post-exposure prophylaxis

- the risk of HIV conversion following a body fluid exposure depends on the type of fluid involved and the part of the body exposed

- an occupational exposure to HIV-contaminated blood through a percutaneous needle puncture is associated with an average 0.3% risk of seroconversion

- a percutaneous exposure with a hollow-core needle has an even greater risk of HIV seroconversion and the risk of seroconversion depends on two variables - the amount of blood to which the person is exposed and the amount of HIV virus in the source blood

- factors increasing the rate of seroconversion include visible blood on the device, a large amount of blood injected percutaneously, a procedure involving the direct placement of the contaminated needle in an artery or vein, and terminal HIV illness of the source patient (which is associated with a high viral load)

- contaminated scalpel blades or solid core needles are associated with a lesser risk of seroconversion

- mucous membrane exposure with blood or body fluids is associated with a risk of seroconversion of ~ 0.1%

- seroconversion is very rare in intact skin exposures and the rare cases of seroconversion after skin exposure have involved large volumes of blood, a large area of skin exposed and/or a prolonged skin contact exposure

- HIV-seroconversion usually occurs within 6 - 12 weeks and ~ 80% of seroconverting HCWs will experience an acute retroviral syndrome illness (usually within 3 - 6 weeks)

- post exposure HIV prophylaxis may decrease the seroconversion rate by a maximum of 80% if given within 1 - 2 hours of exposure, but the actual efficacy depends on the degree of contamination, the viral load and the amount of time delay preceding the commencement of anti-retroviral therapy

- although evidence of decreased post exposure seroconversion has only been demonstrated for one anti-retroviral drug - zidovudine (ZDV) - the basic PEP regimen includes lamivudine (3TC) because it is active against many ZDV-resistant strains and because the combination of ZDV + 3TC is not associated with increased toxicity; certain high risk exposures warrant adding a third drug - a protease inhibitor - which has been shown to markedly reduce the viral load in HIV-treated patients

(PEP with ZDV has only been shown to be effective in animal models and there are no definitive human studies available; there are also case reports of seroconversion despite PEP)

- the efficacy of HIV post exposure prophylaxis is significantly reduced if the patient delays therapy, does not take the correct dose of drugs or prematurely discontinues therapy (a full course of therapy = 4 weeks)

( ~ 1/3 of patients taking PEP anti-retroviral drugs discontinue therapy because of drug side-effects)

- prior to advising the HCW on the need for PEP => determine the exposure code and the HIV status code so that you can decide whether HIV prophylaxis therapy is actually warranted

Step 1: Determine the exposure code

Is the source material blood, bloody fluid or other potentially infectious material (*OPIM) or an instrument contaminated with one of these substances?

(* OPIM includes semen or vaginal secretions, cerebrospinal fluid, synovial, pleural, pericardial, amniotic fluid - but does not include non-blood contaminated sweat, urine, feces, vomitus, saliva or tears)

No => No PEP needed
Yes => Determine the exposure code
 
Determination of the exposure code
Mucous membrane or compromised skin exposure

(compromised skin = chapped skin, dermatitis, abraded skin, open wound)

  Small volume of blood 
  • few drops
  • short duration (secs)
 		 EC1
 
 

 
   Large volume of blood
  • more than several drops
  • major blood splash
  • longer duration (mins)
 EC2
Intact skin exposure
  • Small volume of blood or other body fluid
 No PEP needed
 
  • Large volume of blood or extensive skin exposure or prolonged skin contact
 Consider PEP
Percutaneous exposure  Less severe
  • solid needle
  • superficial scratch
 EC2
   More severe
  • large-bore hollow needle
  • deep puncture
  • visible blood on device
  • needle used in source patient's artery or vein
 EC 3

Step 2: Determine the HIV status code

What is the HIV status of the exposure source

HIV negative => No PEP needed

(a source is considered negative if there is laboratory confirmation of a negative HIV antibody, negative HIV polymerase reaction (PCR), or negative HIV p24 antigen from a specimen collected at the time of exposure and there is no clinical evidence of a recent retro-viral illness)

HIV status unknown => HIV SC unknown

Source unknown => HIV SC unknown

HIV positive

(a source is considered positive if there is a positive HIV antibody, HIV PCR or HIV p24 antigen test; or if the patient has physician-diagnosed AIDS; lower titer exposure = asymptomatic patient, high CD4 count; higher titer exposure = advanced AIDS, primary HIV infection, high or increasing viral load or low CD4 count)

Step 3: Determine the PEP recommendation
 
 
PEP recommendation
EC HIV SC PEP recommendation
1 1 PEP may not be warranted. Exposure type does not pose a known risk for HIV transmission. Whether the risk for drug toxicity outweighs the benefit of PEP should be decided by the exposed HCW and treating physician.
1 2 Consider basic regimen. Exposure type poses a negligible risk for HIV transmission. A high titer in the source may justify consideration of PEP. Whether the risk of drug toxicity outweighs the benefit of PEP should be decided by the exposed HCW and the treating physician.
2 1 Recommend basic regimen. Most HIV exposures are in this category; no increased risk for HIV has been observed but the use of PEP is appropriate.
2 2 Recommend expanded regimen. Exposure type represents an increased HIV transmission risk.
3 1 or 2 Recommend expanded regimen. Exposure type represents an increased HIV transmission risk.
2 or 3  Unknown If the source or, in the case of an unknown source, the setting where the exposure occurred suggests a possible risk for HIV exposure => consider the basic regimen 

(see the appendix for an alternative approach to risk stratifying patients for PEP)

Basic regimen = Zidovudine (600mg/day in 2 - 3 divided doses) + lamivudine (150mg bid)

Expanded regimen = Basic regimen + either indinavir (800mg tid) or nelfinavir (750mg tid)

- both regimens are used for 4 weeks and the cost varies from $500 (two drug regimen) to $1,000 (three drug regimen)

 - whenever possible, these regimens should be implemented in consultation with physicians having expertise in anti-retroviral therapy

- the HCW should be encouraged to participate in PEP decisions - especially if the indications for PEP therapy are equivocal

- the HCW should be highly encouraged to start PEP therapy if the CDC protocol suggest an increased risk of HIV transmission => the HCW can always change his mind later if he decides not to continue PEP therapy (after he has consulted the appropriate expert and considered the matter carefully)

- if the source patient's HIV status is unknown + not possible to obtain rapid HIV testing + high likelihood that the source patient may be HIV positive based on high risk behaviours => strongly consider PEP with a two-drug regimen on a case-by-case basis => the follow-up physician can modify the regimen to three-drugs if the HIV test of the source patient's blood is found to be positive at the time of the follow-up visit and the exposure is deemed a high risk exposure

- if the source patient's HIV test is negative at the time of exposure + source patient participated in high risk behaviours in the 12 week period prior to HIV testing => consider the source patient's blood as high risk and consider PEP therapy

(the same thinking applies to blood from an unknown source if the exposure setting suggests a high likelihood that the the source patient's blood or body fluid could be HIV positive eg. AIDS unit => PEP should be administered on a case-by-case basis)

Drugs commonly used for HIV post exposure prophylaxis
Drug Dosage Side-effects/interactions
Zidovudine (Retrovir, ZDV, AZT) 300mg bid or 200mg tid
(peds = 180mg/m2 q6h -  age 3m - 12 y, adult dose > 12y)		 Neutropenia, anemia, nausea, fatigue, malaise, headache, insomnia, myositis
Lamivudine (Epivir, 3TC) 150mg bid
(peds = 4mg/kg bid - age 3m - 16y)		 Headache, abdominal pain, diarrhea, pancreatitis-rare
ZDV + 3TC (Combivir)  1 tablet bid
(peds dosing not available)		 Toxicity of the combination is equal to ZDV alone
Indinavir (Crixivan, IDV) 800mg q 8h on an empty stomach = 1 h before or > 2h after meals
(peds - not recommended, substitute nelfinavir)		 Nephrolithiasis (reduced by drinking large amounts of water; > 48oz/day), crystalluria, hematuria, nausea, headache, elevated liver function tests, hyperglycemia, many drug interactions - terfenadine, astemizole, cisapride, triazolam, midazolam, rifampin, rifabutin, ketoconazole
Nelfinavir (Viracept) 750mg tid with food
(peds = 20 - 30mg/kg/dose tid - age 2 - 13 y, adult dose > 13 y)		 Diarrhea, hyperglycemia, same drug interactions as indinavir
Stavudine (d4T/Zerit)  40mg bid  for > 60kg, 30mg bid for < 60kg
(peds = 1mg/kg/dose for < 30kg, adult doses > 30kg)		 Pain, peripheral neuralgia, elevated liver enzymes
Didanosine (ddl/Videx) 200mg bid for > 60kg, 125mg bid for < 60kg
(peds = 120mg/m2 bid		 Pancreatitis, stomatitis, peripheral neuropathy; must be taken < 1h before or > 2h after meals

- if the source patient had previously been treated with zidovudine (ZDV) and/or lamivudine (3TC) => consult an infectious disease specialist and consider using other anti-retroviral agents eg. stavudine + didanosine, or another protease inhibitor eg. saquinavir, ritonavir, amprenavir

(the soft-gel formulation of saquinavir "Fortovase" should be used - however, the dose of 1,200mg tid necessitates taking 18 pills per day)

- the NNRTIs (nevirapine and delavirdine) are fast-acting and very potent, but concerns about side-effects and the availability of alternative agents argue against using this group of drugs as initial therapy unless specific indications exist

(see the CDC publication "MMWR report: Appendix - First line drugs for post exposure prophylaxis"  for further details on anti-retroviral drugs)

- the basic regimen is not contra-indicated if the HCW is pregnant, but breast-feeding should be discontinued to avoid exposing the infant to these agents => consult the HCW's obstetrician prior to instituting PEP

(protease inhibitors may increase the risk of pregnancy-associated hyperglycemia => careful monitoring of the serum glucose levels will be required if they are used during pregnancy; the safety and tolerability of protease inhibitors in pregnant patients is unknown)

- advance preperation of drug packages containing a 3 - 5 day supply of drugs is useful because the HCW will not need an immediate prescription  => a prescription for further PEP drug therapy can be the responsibility of the follow-up physician, who will have access to the HIV test of the source patient's blood at the time of the first follow-up visit if rapid HIV testing is not available => positive HIV test => further modification of PEP therapy based on the exposure risk and HIV titer of the source patient's blood

(pre-prepared drug packages also have the advantage that the HCW does not have to seek an "open" pharmacy, which may be especially difficult after-hours or on weekends)

- it is recommended that the hospital develop a special "Consent to PEP therapy" form containing a checklist that should be completed  prior to discharging the HCW from the ED

- discharge instructions should include an instructional leaflet/booklet with basic information on HIV and hepatitis B/C and PEP therapy

(see the CDC's informational booklet on "Exposure to blood - What health-care workers need to know"  which is available in Adobe's pdf format)

 it is strongly recommended that the hospital bank the HCW's baseline sera if the HCW refuses baseline HIV testing or PEP therapy, so that the pre-exposure status of the HCW can be determined if the HCW subsequently develops AIDS

Follow-up recommendations

- all HCWs exposed to HIV positive blood or body fluid should be followed-up, even if the exposure was a minimal intact skin exposure not warranting the initiation of PEP therapy in the ED

- the patient should preferably be seen by an infectious disease specialist within several days for a review of the source patient's HIV test results + expert counselling +/- any needed modification of the PEP regimen +/- a prescription for more drugs if a precription was not given at the time of the ED visit

- if the source patient's HIV test is negative at the time of follow-up visit + PEP was started in the ED => PEP can be discontinued at the discretion of the follow-up physician

- if the source patient's HIV test is positive + high titer exposure and/or EC3 exposure category => the follow-up physician can consider adding a protease inhibitor if only the basic two-drug regimen was initiated in the ED

- the HCW should have repeat HIB antibody testing at 6 weeks, 12 weeks and 6 months

(testing should also be done at 12 months if the HCW develops hepatitis C - because simeultaneous exposure to HCV may delay HIV-seroconversion)

- HCW's receiving PEP should have repeat blood cell counts, renal and liver function tests in 2 weeks to detect anti-retroviral drug toxicity

(monitoring for crytalluria, hematuria, hemolytic anemia and hepatitis should also be perfomed if the HCW is taking IDV)

- HIV testing should be performed if the HCW develops an acute retroviral type illness (fever, rash, malaise, fatigue, myalgia, lymphadenopathy) at any point-in-time during the next 6 - 12 months

- the HCW should seriously consider sexual abstinence (or practice safe sex) and should refrain from donating blood or organs or semen for the next 6 - 12 weeks (until seroconversion has been virtually ruled-out)

- there is no need to modify the HCW's patient care responsibilities to prevent HIV transmission to patients (based solely on the HCW's history of HIV exposure)

- any seroconversion of a HCW should be reported to the CDC

Resources for consultation
Resource or registry Contact information
National Clinicians Postexposure Hotline Tel: (888) 448-4911
HIV Postexposure Prophylaxis Registry Tel: (888) 737-4448
Antiretroviral Pregnancy Registry Tel: (800) 258-4263
FDA (for reporting unusual drug reactions) Tel: (800) 332-1088
CDC (for reporting HIV seroconversions) Tel: (404) 639-6425
National Nonoccupational HIV Postexposure Prohylaxis Registry (http://www.hivpregistry.org) Tel: 877-HIV-1PEP

Non-occupational post exposure HIV prophylaxis

- there is no data on the effectiveness of PEP following non-occupational HIV exposures

- there is no data on the risk of HIV infection or the effectiveness of anti-HIV therapy after sexual assault

- the risk of HIV transmission following a single act of anal receptive intercourse with a HIV-positive person has been estimated to be 0.5 - 3%

- the risk of HIV transmission for discordant heterosexual couples following a single act of penile-vaginal intercourse is 0.1%

- the risk of HIV transmission following receptive fellatio with ejaculation is unknown

- the risk of HIV transmission following needle sharing is 0.4 - 3% per shared injection with a HIV-positive person

- the risk of transmission following sexual assault is probably higher than the same act performed consensually because of additional risk factors - increased likelihood of associated genital trauma, increased likelihood of associated genital infections - especially if there was exposure to multiple assailants and/or involvement of multiple receptive sites

- the CDC has not issued specific guidelines on non-occupational exposures and an individual physician needs to seek guidance from other sources

(see the CDC's "PHS report summarises current scientific knowledge on the use of post exposure anti-retroviral therapy for non-occupational exposures")

- because the risk of HIV transmission following occupational percutaneous blood exposure is 0.3% and the CDC recommends PEP at that rate of risk => PEP could be warranted if a non-occupational exposure has a HIV transmission risk of > 0.3%

- the first comprehensive post-sexual exposure guideline that I found is by Katz: Ann Intern Med, Volume 128 (4) 306 - 312 February 15, 1998  and readers can follow the recommendations if they deem them appropriate
 
Recommendations for post-sexual exposure HIV prophylaxis
Post exposure HIV prophylaxis is recommended if there is:-
  • unprotected receptive anal intercourse
  • unprotected receptive vaginal intercourse
  • unprotected insertive vaginal intercourse
  • unprotected insertive anal intercourse
  • unprotected receptive fellatio with ejaculation
with a HIV positive person or if the person is a HIV risk group (gay or bisexual men, injection drug users or sex workers), and if the exposure is isolated and the patient is commited to safer sex in the future and the exposure occurred within 72 hours of presentation for care

- clinically, it is irrelevant whether the patient was an "innocent victim" or a "knowing participant" and PEP should be considered in all sporadic HIV exposures

- it is important to determine the likely risk of repeat exposures - continuing exposures would in effect require ongoing prophylaxis and PEP is not recommended for likely repeat exposures

- the HIV status of the patient should be determined at the time of ED presentation using a rapid HIV antibody test

- HIV positive patients do not require PEP => an optimal regimen for primary or long-standing HIV infection is more suitable

- consider adding a protease inhibitor anti-retroviral drug if the source patient is known to be HIV-positive + has known high HIV viral load and/or has known resistance to standard NRTI drugs

- note that some authorities take a more aggressive approach and they recommend triple therapy in all sexually assaulted patients exposed to HIV-positive sources or HIV-unknown sources with high HIV risk factors, and they even recommend the basic two-drug regimen for exposure to HIV-unknown source patients with low HIV risk factors

Standard PEP regimen as suggested in "Non-occupational HIV post-exposure prophylaxis: A new role for the Emergency Department" by RC Merchant in the Annals of Emergency Medicine 36:4 366 - 375 October 2000
 
Exposure to persons known to be HIV infected
  • if medication regimen of source patient is unknown => prescribe Zivudine (AZT/ZDV) 300mg bid + Lamivudine (Epivir) 150mg bid + Indinavir (Crixivan) 800mh q8h or nelfinavir (Virasept) 1250mg bid or 750mg tid
  • Combivir 1 tablet bid may be substituted for zidovudine and lamivudine
  • if medication regimen of source patient is known => prescribe 2 NRTIs and 1 protease inhibitor that are different from the source patient's regimen
  • possible substitues for zidovudine and lamivudine:- stavudine (d4T/Zerit) 40mg bid for > 60kg and 30mg bid < 30kg, and didanosine (ddl/Videx) 200mg bid for > 60kg and 125mg for < 60kg; exception: zidovudine and stavudine should not be used together
Exposure to person or persons of unknown HIV status but who probably have high HIV risk factors
  • significant exposures => treat as if an exposure to a known HIV-infected person with an unknown medication regimen, as above
  • exposures that might result in HIV infection => treat with zidovudine and lamivudine without a protease inhibitor
Exposure to person or persons of unknown HIV status but who probably have low HIV risk factors
  • significant exposures => treat with zidovudine and lamivudine. A protease inhibitor could be added if the patient requests it, if the provider believes that the exposure history is unclear, other exposures also occurred, or if other factors relating to exposure history or HIV status are compelling
  • exposures that might result in HIV infection => treat with zidovudine and lamivudine without a protease inhibitor
Additional caveats
  • PEP should not be provided to patients whose exposure history has no known possibility for HIV transmission
  • PEP should not be given to persons already infected with HIV
  • providers may consider PEP for any patient who appears to be at risk after an HIV exposure but whose circumstances are not delineated in the above categories
Providers are reminded that PEP should only be prescribed as part of a comprehensive program to reduce future HIV risk-related behaviours. Multiple prescription requests for PEP should be strongly discouraged and must be averted through risk reduction counselling

Definitions:

High HIV risk factors: trading sex for drugs or money, IV drug use, unprotected anal or vaginal intercourse with persons with HIV risk factors
Significant exposures include the following: anal or vaginal intercourse without a condom or with condom breakage; exposure to semen or blood onto mucosal or nonintact surfaces, and intravenous needle sharing
Examples of exposures that might result in HIV infection are as follows: cunnilingus, fellatio, semen or blood on healing skin wounds

- patients with sexual exposure to HIV should also be tested for other sexually transmitted diseases - syphilis, gonorrhea, chlamydia, hepatitis B, and hepatitis C

- all patients, regardless of HIV status, should be referred to a risk-reduction counseling program, which can provide ongoing multiple-session counseling

- for substance abusers, referal to a  substance abuse treatment program is appropriate

Hepatitis B

- the risk of contracting hepatitis B following a needle-stick injury from a HBsAg positive source patient is ~ 26%, and is considerably higher than the risk of contracting HIV following a needle-stick exposure to HIV positive blood (~ 0.3%)

- the risk depends on the infectivity of the source patient; ~ 40% if the source patient is HBeAg positive and only ~ 2% if the source patient is HBeAg negative

(the risk is negligible if the source patient is HBsAb positive, but HBsAg negative)

- the risk of contracting hepatitis B  is considerably less if the body fluid was not blood - the titer of HBV is 1/1,000 - 1/10,000 lower in semen and saliva compared to blood

- all HCWs not known to be immune to hepatitis B should receive a three-dose vaccine series (0, 1 and 6 months after exposure) => retested for anti-HBs 1 - 2 months after completing the vaccine series

- if the HCW has been previously vaccinated against hepatitis B and has a documented positive antibody response > 10 mIu/ml at any point-in- time in the past => no further treatment is necessary

(HCW's who are immunosuppressed should be retested for anti-HBs levels after exposure)

- if the HCW has an unknown antibody response to a previous vaccination => give HBIG + booster dose of HB vaccine

(HBIG should also be given to a person who has never been vaccinated against hepatitis B eg. non-occupational exposure)

- the HBIG should be given within 72 hours and at a different site than any hepatitis B vaccine

(HBIG does not have to be given in the ED if the HBsAg results of the source patient's blood is not immediately available and the source person is not a high-risk patient => HBIG can be given at the 48 hour follow-up visit if the source patient's blood comes back HBsAg positive and the HCW has an inadequate level of anti-HBs)

Recommended PEP for percutaneous or permucosal exposure to HBV
Vaccination and antibody response of exposed person  Source
HbsAg-positive		 Source
HBsAg-negative 		 Source not tested or unknown source
Unvaccinated HBIG x 1 => initiate hepatitis vaccine series Initiate hepatitis B vaccine series  Initiate hepatitis B vaccine series
Previously vaccinated 
  • known responder
 No treatment No treatment No treatment
Previously vaccinated
  • known non-responder
 HBIG x 2, or HBIG x1 and initiate revaccination No treatment If known high-risk source => treat as if HB-positive
Previously vaccinated
  • antibody response unknown
 Test exposed person for anti-HBs
  • if adequate => no treatment
  • if inadequate => HBIG x1 and vaccine booster
 No treatment Test exposed person for anti-HBs
  • if adequate => no treatment
  • if inadequate => initiate vaccination

- no special precautions are necessary with respect to household contacts, sexual contacts or with patient care

Hepatitis C

- chronic liver disease develops in 70% of all HCV positive persons

- the risk of seroconversion following blood exposure is unknown and is thought to be ~ 1.8% (range of 0 - 7%)

- seroconversion is detected by measuring the anti-HCV, which becomes positive within 3 - 4 months in 80% of cases and by 6 months in virtually all seroconverting persons

- earlier seroconversion can be detected by a polymerase chain reaction for HCV RNA (PCR), which becomes positive within a few weeks of exposure

- HCV RNA is not detected in urine, feces, saliva, vaginal secretions or semen and the risk of transmission following contact with those body fluids is very small

- PEP has not been shown to prevent seroconversion and immunoglobulin is not helpful in preventing HCV infection

- exposed HCW's should be tested for anti-HCV and alanine aminotransferase at baseline and again in 6 months

- if earlier diagnosis is desired HCV RNA testing can be done at 4 - 6 weeks

(interferon use has been suggested for seroconverting HCW's who have a persistently elevated alanine aminotransferase level and a liver biopsy showing inflammation and necrosis)

- there is an extremely low risk of secondary sexual transmission and the most conservative approach would be to avoid unprotected sexual contact for 6 - 9 months until seroconversion has been ruled-out

- no special precautions are necessary with respect to household contacts or patient care

(see the CDC's MMWR report "Recommendations for the prevention and control of HCV infection and HCV-related chronic disease")

Appendix

- in the article on "HIV prophylaxis for Health Care Workers" in the Journal of Occupational and Enviromental Medicine, Linda S. Forst suggests calculating the risk of HIV seroconversion and number-needed-to-treat as follows:-

Number of HCW's that would have to be treated to prevent one case of HIV seroconversion
Risk factor Seroprevalence Seroconverting rate No. of cases seroconverting No. to treat to prevent one case 
Known HIV+ source - deep needlestick 100% 0.3% 1/325 361
Known HIV+ source - mucous membrane/skin 100% 0.1% - 0.3% 1/1,000 - 1/325 361 - 1,111
HIV  unknown - high risk (deep needlestick) 25%* 0.3% 1/325 9027
HIV unknown - high risk (mucous membrane) 25%* 0.1% - 0.3% 1/1,1000 - 1/325 9,027 - 27,778
HIV unknown -low risk (deep needlestick) 1%* 0.3% 1/325 36, 111
HIV unknown - low risk (mucous membrane) 1%* 0.1% - 0.3% 1/1,000 - 1/325 36,111 - 111,111

(* - assumes a 25% HIV positivity rate in a high risk setting eg. San Francisco General hospital ward and a low risk rate of 1% in the general hospital population)

Modifications to US Public Health Service Recommendations for HIV PEP in exposed HCWs
  HIV+, acute HIV or end-stage HIV HIV+, no active disease HIV unknown, high risk HIV unknown, low risk  Source unknown
Deep injury - device previously in vasculature, or hollow or solid needle, or blood or OPIM on injury device Increased risk - recommend 1+2+3 Increased risk - recommend 1+2+3 Increased risk - recommend 1+2+3 Slightly increased risk - not promote Slightly increased risk - not promote
Superficial scratch - hollow or solid needle Increased risk - recommend 1+2+3 Slightly increased risk - not promote Slightly increased risk - not promote Not increased - not offer Not increased - not offer
Blood (spash) on non-intact skin or mucous membrane Increased risk - recommend 1+2+3 Increased risk - recommend 1+2+3 Increased risk - recommend 1+2+3 Not increased - not offer Not increased - not offer
Blood on intact skin Increased if high quantity - not promote Increased if high quantity - not promote Increased if high quantity - not promote Not increased - not offer Not increased - not offer
Body fluid other than plasma-based (urine, saliva, sweat) Not increased - not offer Not increased - not offer Not increased - not offer Not increased - not offer Not increased - not offer

(the author recommends triple anti-retroviral therapy in all cases requiring PEP)

Sample form - Consent to be treated with post exposure prophylaxis (PEP)

Purpose and background

I may have been exposed to human immunodeficiency virus (HIV), the virus which causes AIDS. The risk of infection from my exposure is not known with certainty, but my physician has assessed my risk and found my risk to be ________ . Based on risk  assessment, my physician has recommended one of the following regimens of anti-retroviral drugs:-

"Basic" two drug regimen

"Expanded" three drug regimen Although the above PEP is indicated for treatment of established HIV infection, there is no proof that it will prevent infection following occupational or non-occupational exposures.

My physician-nurse team has instructed me on the following:-
 
_____  Recommendations for PEP were explained to me.
_____ Knowledge about the efficacy and toxicity of drugs used for PEP are limited.
_____ Only ZDV has been shown to prevent HIV transmission in humans.
_____ There are no data to address whether adding other anti-retroviral drugs provides any additional benefits for PEP, but experts recommend combination drug regimens because of increased potentcy and concerns about drug resistant virus.
_____ Data regarding toxicity of anti-retroviral drugs in persons without HIV infection and pregnant women are limited for ZDV and not known regarding other anti-retroviral drugs.
_____ Any and all drugs for PEP may be declined.
_____ I must follow up with ___________ in order to continue the PEP regimen. My physician provided me with enough drugs to last until my follow-up appointment on __________ .
_____ Dose reduction, drug substitution, and further diagnostic studies will be determined by the follow-up physician as part of the follow-up PEP program. 
_____ I was provided with a PEP instruction leaflet/booklet.

I HAVE BEEN GIVEN THE OPPORTUNITY TO ASK QUESTIONS RELEVANT TO MY POST EXPOSURE PROPHYLAXIS TREATMENT. IF I HAVE FURTHER  QUESTIONS, I MAY CONTACT ____________ .

______ YES, I agree to post exposure prohylaxis as explained to me by my physician-nurse team.
______ NO, I refuse the post exposure prophylaxis as explained to me by my physician-nurse team.

______________________________                        _________________
Exposed person's signature                                         Date

______________________________
Exposed person's name

______________________________
Physician's signature

  _____________________________
Nurse's signature

Recommended review journal articles and web based educational resources

1) Emergency department management of blood and body fluid exposures: Moran GJ - Annals of Emergency Medicine 35 (1) 47 - 62 January 2000

2) Drug therapy: Managment of occupational exposures to blood-borne viruses: Gerberding JL - NEJM 332 (7) 444 - 451 16 Feb 1995

3) Public health service guidelines for the management of health-care worker exposures to HIV and recommendations for postexposure prophylaxis - MMWR 47 (RR-7) May 15, 1998

4) B.C. Center for Excellence in HIV/AIDS - The therapeutic guidelines for the treatment of HIV/AIDS and related conditions: Section 7: Management of accidental exposure to HIV

(the best web-based source of information on the management of HIV PEP that I have found - it has an especially good section on pediatric anti-retroviral drug doses and the management of human bites)

5) Postexposure prophylaxis after nonoccupational HIV exposure: Clinical, ethical and policy considerations: Lurie P - JAMA 280 (20) 1769 - 1773 November 25, 1998

6) The care of persons with recent sexual exposure to HIV: Katz MH - Annals of Internal Medicine 128 (4) 306 - 312 February 15, 1998

7) HIV testing, counseling, and prophylaxis after sexual assault: Gostin LO - JAMA 271 (18) 1436 - 1444 May 11, 1994

8) HIV prophylaxis for Health Care Workers: Forst LS - J of Occup and Envir Medicine 39 (12) 1212 - 1219 December 1997

10) Nonoccupational HIV postexposure prophylaxis: A new role for the Emergency Department: RC Merchant - Annals of Emergency Medicine 36:4 366 - 375 October 2000)

Commentary, criticism and controversy