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Occupational Exposure to HIV: Universal Precautions and PEP

HAIVNHarvard Medical School

AIDS Initiative in Vietnam

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Learning Objectives

By the end of this session, participants should be able to:

Explain the risk of HIV transmission after a single percutaneous exposure

Demonstrate “scoop” technique of recapping needles

List the steps involved in post-exposure prophylaxis (PEP)

Describe PEP regimens in Vietnam

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HIV Transmission Through Occupational Exposure

HIV transmission as a result of an occupational exposure is a rare event

The majority of transmissions occur by exposure to HIV-infected blood

The overall risk of HIV transmission depends on the route and severity of exposure

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Risk of HIV Transmission

Blood exposures Risk of HIV Transmission

Percutaneous needlesticks0.3%

(95% CI=0.2-0.5%)

Mucous membranes0.09%

(95% CI 0.006% -0.5%)

Intact Skin0%

(95% CI =0.0%-0.77%)

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Factors that Increase Risk of Transmission

Factors that increase the risk of HIV transmission from a needle stick injury include exposure: • through a visibly bloody device• through a device used in an artery or vein• via a deep injury• from a source individual with more advanced

HIV disease and a high HIV viral load

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Body Fluids and Risk for HIV Exposure

Potential Risk Blood Cerebrospinal fluid

(CSF) Pleural fluid Peritoneal fluid Any body fluid visibly

contaminated with blood

Negligible Risk* Urine Saliva Sputum Sweat Feces Vomitus

* If not visibly contaminated with blood

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Questions: What does the term

“Universal Precautions” mean?

What are some examples of Universal Precautions?

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Universal Precautions (1)

#1 Treat ALL blood and body fluids as if they are potentially infectious

Follow Universal Precautions

#2 Prevent needle sticks

Safely manage sharps

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Universal Precautions (2)

Following universal precautions means minimizing exposure to blood and body fluids through:• Use of protective barriers• Hand hygiene• Safe injection practices• Environmental control of blood and

bodily fluids• Sharps management

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1. Use of Protective Barriers

Procedure Gloves Gown Goggles/Face Protection

Giving an injection No No No

Drawing blood Yes No No

Irrigating a wound Yes Yes Yes

Performing an operation Yes Yes Yes

Guidelines on when to use protective barriers

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2. Hand Hygiene

Prevents transmission of resistant organisms and infections• Before patient care• After blood/fluid contact, glove removal

Methods:• Hand washing• Use hand sanitizer

60-95% ethyl or isopropyl alcohol

http://www.cdc.gov/handhygiene

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3. Safe Injection Practices

Use a sterile syringe and needle for every infection; use the correct intended medication

Place needle in a puncture-proof container right after use

Discard sharps waste appropriately

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4. Environmental Control of Blood and Body Fluids

Spills in patient-care areas

Clean visible blood/fluid with towel and discard

Disinfect area• 1:100 dilution (500

ppm) of hypochlorite

Spills in laboratory areas

Soak towel and blood/fluid spill in disinfectant before discarding

Use more potent disinfectant• 1:10 dilution (5000

ppm) of hypochlorite

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5. Sharps Management

Injuries can occur whenever a sharp is exposed in the work environment, therefore it is important to:

Organize work areas• Have sharps containers nearby

Avoid hand-passage of sharps Not recap needles, or: recap using a

one-handed “scoop technique”

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“One-hand” Technique of Recapping Needles

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Post-Exposure Prophylaxis (PEP)

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Post-Exposure Prophylaxis (PEP)

The use of therapeutic agents to prevent infection following exposure to a pathogen

Types of occupational exposure include:• Percutaneous injury (needle-stick or cut

through the skin)• Contact of mucous membrane or non-intact

skin with bodily fluids that are potentially infectious

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PEP Rationale (1)

Information about primary HIV infection indicates that systemic infection does not occur immediately

There is a brief delay between exposure to virus and appearance of HIV in the blood

During this “window of opportunity” antiretroviral treatment may prevent systemic infection

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PEP Rationale (2)

Animal models show that following exposure to HIV:• immune cells at site of HIV entry become

infected within first 24 hours• infected cells move to regional lymph

nodes over next 24-48 hours• within 5 days HIV is detectable in the blood

ARVs given soon after exposure may prevent infection by blocking HIV replication in the few cells that are initially infected

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Efficacy of Antiretroviral Therapy

Case Control study: 31 cases, 679 controls

Cases acquired HIV following an occupational exposure• 94% after needle stick (all hollow needles)

29% of cases received PEP (AZT) vs. 36% of controls

Risk for HIV infection reduced by ~81% in HCWs receiving AZT

Cardo D. NEJM 1997; 337:1485-90

Human data-CDC Needle Stick Surveillance Group

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Steps for Post-Exposure Management

1. Treat the exposure site 2. Report the exposure to the manager and

complete the report form3. Assess the risk of exposure 4. Determine the HIV status of the source of

exposure 5. Determine the HIV status of the exposed

person.6. Counsel the exposed person.7. Provide ARV prophylaxis (if indicated)

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National Guidelines on PEP Regimens (1)

Medications Indications2 drug regimen (basic regimen)

AZT+ 3TC

OR

d4t + 3TC

All exposures with risk

3 drug regimen AZT+ 3TC

OR

d4t + 3TC

Plus: LPV/r

In case source of exposure is

known to have or suspected of ARV

resistance

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National Guidelines on PEP Regimens (2)

Dosages:• AZT: 300mg BID PO• 3TC: 150mg BID PO• d4T: 30mg BID PO• LPV/r: 400mg/100mg BID PO

Nevirapine is not recommended due to fulminant liver failure in 4 American HCW taking it for PEP

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Suggested Post-Exposure Follow-up and Testing

Test health care worker for HIV after 4-6 weeks, 3 months, and 6 months

Conduct laboratory tests to monitor ARV side effects:• CBC, ALT at baseline and after 4 weeks

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Risk of Seroconversion afterPercutaneous Occupational Exposure

Virus Range MeanHBV 2 – 40 % 30%

HCV 0 – 7 % 3 %

HIV 0.2 – 0.5 % 0.3%

HBV is 100x more transmissible than HIV!

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Case Study, Part 1

A nurse sustains a percutaneous (needle stick) injury to her index finger

The source patient is a woman who is at the OPC for her second visit and is known to be HIV-infected

Her clinical status and CD4 count have not yet been established

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Case Study: Questions

1. What steps should be taken immediately?

2. You are responsible for counseling the nurse about PEP. What is the risk of acquiring HIV from a known HIV-infected source patient? What questions about the incident could you ask her to assess her risk?

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Case Study, Part 2 (1)

On questioning, the nurse reports that she was wearing gloves when her finger was stuck by a 21-gauge phlebotomy needle that had just been used to draw blood from the vein of the source patient

The needle was visibly bloody at the time she was stuck, and she is not sure if it was a ‘deep’ stick or not, but she says “it made my finger bleed” a lot.

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Case Study, Part 2 (2)

She does not think she is pregnant She has never been tested for HIV

but has no reason to believe that she might have HIV infection

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Case Study: Questions

3. What are your PEP recommendations for the nurse?

4. What additional testing and follow-up care should be performed for the exposed nurse? What additional advice and counseling would you offer?

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Key Points

The term “Universal Precautions” means treating all blood and body fluids as if they are infectious

Risk of transmission from a single occupational exposure for:• HIV = 0.3%• HBV = 30%

PEP in Vietnam should follow MOH guidelines

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Thank you!

Questions?