Worldwide,  up to the end of year  2002, there were total 106 documented and 238 possible occupationally acquired HIV seroconversion temporally associated with an occupational HIV exposure. Percutaneous needle injury involving hollow-bore needles are commonly implicated.

Management

Immediate washing of the wound with soap and water thoroughly

Small wound and puncture may be cleansed with antiseptic eg alcohol based hand hygiene agent

Disinfection of wound and dressed

Mucosal contact: immediately and liberally wash the exposed parts with water or saline

Seek proper medical advice for proper wound care and post-exposure management

Referral for follow-up and reporting

In Hong Kong, health care personnel can seek advice and obtain initial treatment at Emergency Department of any public hospitals. For subsequent treatment, the health care personnel can be referred to the Therapeutic Prevention Centre of Kowloon Bay Integrated Treatment Centre for exposure management

The health care personnel should also inform Infection Control team of hospital for advice and counselling

The supervisor of the health care personnel should also document the incident and report to Labour Department

Assess severity of exposure

Blood tests:

Baseline blood tests for the health care personnel

• anti-HIV antibody
• complete blood picture
• renal/liver function tests
• serum glucose
• HBsAg
• anti-HCV
• pregnancy test for female health care personnel
• Obtain anti-HIV , HBsAg and anti-HCV status from source patient if possible

For those on post-exposure prophylaxis, monitor

• anti-HIV antibody
• complete blood picture
• renal/liver function tests
• serum glucose
• amylase

Creatinine kinase at 2 weeks, 4 weeks and 3 months

Follow up HIV antibody testing for health care personnel at 6 months

An additional testing at 12 months can be considered on individual basis for highly infectious source for fear of delayed seroconversion

HIV

HIV/AIDS statistics in Hong Kong from 1984 to 2006

Rationale of post-exposure prophylaxis

nIn a primate model of simian immunodeficiency virus (SIV) infection, infection of dendritic-like cells occurred at the site of inoculation during the first 24 hours following mucosal exposure to virus.

 

nOver the subsequent 24-48 hours, migration of these cells to regional lymph nodes occurred, and virus were detectable in the peripheral blood within 5 days.

Retrospective case control study showed health care workers exposed to HIV had reduction in risk of HIV infection if they were given prophylaxis

nInterval beyond which PEP is no longer effective has not been established.

nIt is best to encourage the HCW to initiate PEP early . Animal studies suggest that early first dose is very important and there is minimal  toxicity in 24 to 48 hours of PEP. This will allow time to discuss until final decision is reached.

nPerform HIV rapid test (commercial test kits) for the source.

　

Recommended post-exposure prophylaxis (PEP) for different type of exposure

　

Infection Status of source patient
Exposure type	HIV + Class 1	HIV + Class 2	HIV status unknown	Unknown source	HIV -ve
Less severe	Recommend basic PEP	Recommend expanded PEP	Generally no PEP Consider basic PEP if source patients have risk factor for HIV	Generally no PEP Consider basic PEP if exposure to HIV infected persons is likely	No PEP
More severe	Recommend expanded PEP	Recommend expanded PEP	Generally no PEP Consider basic PEP if source patients have risk factor for HIV	Generally no PEP Consider basic PEP if exposure to HIV infected persons is likely	No PEP

　

Class 1: asymptomatic HIV or low viral load (< 1500 RNA copies/ml)

Class 2: known acute HIV seroconversion /AIDS or high viral load

Less severe exposure: solid needle or superficial injury

More severe exposure: large-bore hollow needle, deep puncture, intramuscular injection, actual injection of blood into artery or vein, visible blood on device, needle used in patient's artery or veins, laceration producing bleeding, fresh wound exposed to infected blood or fluid

Risk is increased with high viral load in end stage AIDS or acute HIV seroconversion

Risk is increased with blood or blood contaminated fluid

Risk factors	Adjusted odds ratio
Deep injury	15
Visible blood in device	6.2
Procedure involving needle in artery or vein	4.3
Source patients have terminal AIDS	5.6

Basic PEP: 2 drugs

• Two NRTI or NRTI + NNRTI

  zidovudine (ZDV) + 3TC (Combivir)

  zidovudine (ZDV) + lamivudine

Expanded PEP: 3 or more drugs

• Basic PEP with addition of PI for example indinavir, efavirenz, Kaletra

　

Treated for 4 weeks

If given PEP and later source is found to be HIV -ve, PEP should be discontinued

　

Nucleoside reverse transcriptase inhibitors (NRTI)

• zidovudine (ZDV)
• Lamivudine (3TC)
• Stavudine (d4T)
• Didanosine (ddI)

Nucleotide analogue reverse transcriptase (NtRTI)

• Tenofovir (TDF)

Nonnucleoside reverse transcriptase inhibitors (NNRTI)

• Efavirenz (TDF)

Protease inhibitors (PI)

• Indinavir
• Nelfinavir
• Ritonavir
• Saquinavir

Fusion inhibitor

Contraindication to PEP

• Significant hepatic or renal insufficiency
• Bone marrow dysfunction
• Immunosuppression
• pregnancy or breast feeding was contraindicated previously, now should be considered on individual basis

Check baseline HIV status, repeat at 6 weeks, 12 weeks and 6 months after exposure

Repeat HIV test whenever there is symptom compatible with retroviral infection regardless of the time interval

Counselling and education

Prevent secondary transmission

• sexual abstinence or use of condom
• avoid pregnancy
• no blood , organ, tissue or semen donation
• risk of transmission if breast feeding

Alert for side effects of PEP

• Didanosine : pancreatitis
• Efavirenz: Stevens-Johnson syndrome
• Indinavir: hyperglycaemia
• Saquinavir: nephrolithiasis

Alert for symptom of primary infection

unexplained fever, rash, myalgia, fatigue or lymphadenopathy

nEmotional impact is often substantial for the health care personnels

nAlthough the risk of transmission is low, they are committed to 4-weeks of drugs treatment with significant side effects  and  need for behavioural  modification to prevent secondary transmission

　

Failure of PEP have been reported

l16 cases of ZDV failure in healthcare personnel

l5 cases of failure of combination HIV PEP failure

Possible causes

• ndelay in treatment
• ndose too low / low drug levels
• nresistant  virus
• nhigh inoculum exposure
• ntreatment duration too short

Epidemiology of hepatitis in Hong Kong

　

Recommended guidelines for post-exposure prophylaxis against hepatitis B infection

　

	Post-exposure prophylaxis
	Previously vaccinated			No previous vaccination
	Known responders	Known non-responders	Unknown responders	HBsAg -ve	HBsAg +ve
Source known
a) HBsAg +ve	Nil	HBIg in 24 hours repeat after 1 month	Dependent on antiHbs status of exposed person	HBIg+HB vaccine	Nil
b) HBsAg -ve	Nil	Nil	Nil	HB vaccine	Nil
c) HBsAg unknown	Nil	Dependent on source HBsAg status	Dependent on anti-Hbs status of exposed person		Nil
Source unknown	Nil	as in (a)	as in (a)	as in (a)	Nil

　

When indicated, 1 dose of hepatitis B immunoglobulin should be given within 24 hours of exposure and preferably within 7 days

For a previously vaccinated person with unknown result of antibody response, he should be tested for the status of anti-HBs

No treatment is required if the anti-HBs status is positive

Hepatits B immunoglobulin with or without hepatitis B vaccine can be given if anti-HBs status is negative

HCV

Epidemiology of hepatitis C in Hong Kong

Anti-HCV serological + status

• ranged from 0.04% to  0.1 %  in new blood donors from 1991 to 2004
• up to 0.3% in prevalence study by department of health
• up to 9.8% in all ever-tested HIV/AIDS patients
• as high as 98% in HIV/AIDS patients who are drug users

No effective vaccine or prophylactic agent for preventing HCV infection after occupational exposure

Surveillance of exposure to blood-borne viruses (HIV,HBV,HCV) and its management in HK

Preventing needlestick injuries in health care settings

Needle stick injuries related to certain work practices

• recapping
• transferring of body fluid between containers
• failure of proper disposal of used needles in puncture resistant sharps container

Desirable characteristics of devices with safety features

• nNeedleless.
• nSafety feature as integral part of the device.
• nThe device works passively.
• nCan easily tell whether the safety feature is activated.
• nCannot be deactivated
• nReliable performance
• nEasy to use and practical.
• nSafe and effective for patient care

　

Definitions

nHealth-care personnel

person involving contact with patients or with blood or other body fluids from patients in a health-care, laboratory, or public-safety setting.

　

 

nOccupational exposure

 percutaneous injury (needle stick or cut with sharp objects) or contact of mucous membrane or non-intact skin with blood, tissue, or other body fluids that are potentially infectious.

　

 

nOther potentially infectious body fluids

semen; vaginal secretion; amniotic, cerebrospinal, pleural, pericardial, peritoneal, and synovial fluid; or any fluid visibly contaminated with blood.

nHIV+ source

person with known HIV-positive serological status, one clinically diagnosed with AIDS, or a high-risk person with compatible signs and symptoms.

References

1) Scientific Committee of the Hong Kong Advisory Council on AIDS and the Scientific Working Group on Viral Hepatitis Prevention of the Department of Health. (March 2003)  Recommendations on the management and post-exposure prophylaxis of needlestick injury or mucosal contact to HBV, HCV and HIV (English version) (Chinese version)

2) Schalm SW, Buster EH. Management of hepatitis B virus infected health care workers based on HBV DNA levels. J Clin Virol. 2003; 27: 231-234

3) Buster EH, van der Eijk AA, Schalm SW. Doctor to patient transmission of hepatitis B virus: implications of HBV DNA levels and potential new solutions. Antiviral Res. 2003; 60: 79-85

4) Cardo DM et al. A case control study of HIV seroconversion in health care workers after percutaneous exposure. Centers for Disease Control and Prevention Needlestick Surveillance Group. N Engl J Med 1997; 337: 1542.

5) Centre for health protection. Therapeutic prevention of HIV infection