Health care workers and HIV prevention
Occupational exposure to HIV
In many countries for many years health care workers have become infected with HIV as a result of their work. The main cause of infection in occupational settings is exposure to HIV-infected blood via a percutaneous injury (i.e. from needles, instruments, bites which break the skin, etc.). The average risk for HIV transmission after such exposure to infected blood is low - about 3 per 1,000 injuries. Nevertheless, this is still understandably an area of considerable concern for many health care workers.
Certain specific factors may mean a percutaneous injury carries a higher risk, for example:
- A deep injury
- Late-stage HIV disease in the source patient
- Visible blood on the device that caused the injury
- Injury with a needle that had been placed in a source patient's artery or vein
If percutaneous exposure occurs then the site of exposure should be washed liberally with soap and water but without scrubbing. Bleeding should be encouraged by pressing gently around the site of the injury (but taking care not to press immediately on the injury site). It is best to do this under a running water tap.
There are a small number of instances when HIV has been acquired through contact with non-intact skin or mucous membranes (i.e. splashes of infected blood in the eye). Research suggests that the risk of HIV infection after mucous membrane exposure is less than 1 in 1000. If mucocutaneous exposure occurs then the affected area should be washed thoroughly with soap and water. If the eye is affected, it should be irrigated thoroughly.
If intact skin is exposed to HIV infected blood then there is no risk of HIV transmission.
Although infection through needlestick injury does not often occur, it can be devasting for the person concerned as the following account sent to AVERT shows:
"I am a lab tech. I worked 11-7 shift for the past 9 and half years. My job includes drawing blood, testing blood and urine samples in a hospital laboratory, and preparing blood transfusions for patients who need blood products. On 12/31/93 at 3.55am I was called to the emergency room to draw blood on an hiv+ drug abuser, it seems she was out of cash but wanted more 'pain meds". The doctors wanted blood tests first to find out what was she sick with. I ended up trying to draw her blood and she became violent, jerking her arm around after I had a needle in her vein and was getting blood out of her arm. She managed to get the dirty needle stabbed into my left thumb. When I saw that needle in my hand I felt a chill go down my spine and dreaded I would become positive too.
When I saw that needle in my hand I felt a chill go down my spine and dreaded I would become positive too.
- Lab technician.
"Well by march of 1994 I was hiv+. Since then I have tried many of the hiv meds on the market. Many have given me allergic reactions, some have simply been ineffective, others the virus has grown resistant to. It's a month to month battle. So far my t counts are holding and my viral load is between non detected and 10,000. I am married and had a son aged 18 months at the time I was infected. He's now 9.5 years old and the pride of my life. How can I ever tell him mom may not be around much longer? On October 28, 2000 we were blessed with the birth of a daughter. Beautiful is her description by anyone who has seen her. Tonight I received the results of her 1 year hiv test. It is positive."
How many occupational infections have been reported?
Up until December 2006, health care workers in the USA reported 57 occupational HIV infections. Of these, 48 had percutaneous exposure; 5, mucocutaneous exposure; 2, both percutaneous and mucocutaneous exposure; and 2, an unknown route of exposure. In addition, 140 possible occupational transmissions have occurred among healthcare personnel. These are cases in which a worker is infected with HIV and has a history of occupational exposure, but did not have a test immediately before and after the possible exposure. As no other risk factors are reported, it is most likely that the infection has occurred as a result of that occupational exposure. The occupations of these people are presented below.1
| Occupation | Documented occupational transmission | Possible occupational transmission |
|---|---|---|
| Dental worker including dentist | 0 | 6 |
| Embalmer/morgue technician | 1 | 2 |
| Emergency medical technician/paramedic | 0 | 12 |
| Health aide/attendant | 1 | 15 |
| Housekeeper/maintenance worker | 2 | 13 |
| Laboratory worker, clinical | 16 | 17 |
| Laboratory technician, nonclinical | 3 | 0 |
| Nurse | 24 | 35 |
| Physician, nonsurgical | 6 | 12 |
| Physician, surgical | 0 | 6 |
| Respiratory therapist | 1 | 2 |
| Technician, dialysis | 1 | 3 |
| Technician, surgical | 2 | 2 |
| Technician/therapist, other than listed | 0 | 9 |
| Other health care occupations | 0 | 6 |
| Total | 57 | 140 |
It should be noted that because of the voluntary nature of the reporting system, there might be some under-reporting of cases. In addition, the U.S. Centers for Disease Control and Prevention emphasise that over 90 percent of health care workers that are infected with HIV also have non-occupational risk factors for acquiring their infection2.
In the UK, as of February 2008, the Health Protection Agency (HPA) reported that there have been five documented cases of HIV infection after occupational exposure in the healthcare setting, the last being in 19993.
What are Universal Precautions?
Employing universal precautions means taking precautions with everybody. If precautions are taken with everyone, health care workers do not have to make assumptions about people's lifestyles and risk of infection. Health care workers should have the right to be able to protect themselves against infection, whether it is HIV, Hepatitis or anything else.
The following universal infection control precautions are advised by the World Health Organization4 to help protect health care workers from blood-borne infections including HIV:
- Wash hands with soap and water before and after procedures.
- Use protective barriers such as gloves, gowns aprons, masks, goggles for direct contact with blood and other body fluids.
- Disinfect instruments and other contaminated equipment.
- Handle properly soiled linen. (Soiled linen should be handled as little as possible. Gloves and leakproof bags should be used if necessary. Cleaning should occur outside patient areas, using detergent and hot water.)
- Use of new, single-use disposable injection equipment for all injections is highly recommended. Sterilizable injection should only be considered if single use equipment is not available and if the sterility can be documented with Time, Steam and Temperature indicators.
- Discard contaminated sharps immediately and without recapping in puncture and liquid proof containers that are closed, sealed and destroyed before completely full.
- Document the quality of the sterilization for all medical equipment used for percutaneous procedures.
Post Exposure Prophylaxis
Research evidence seems to suggest that the use of anti-HIV drugs if given soon after an injury can reduce the rate of transmission. Such treatment is referred to as Post Exposure Prophylaxis (PEP). PEP is recommended for health care workers if they have had a significant occupational exposure to blood or another high risk body fluid which is likely to be infected with HIV.
Although exposure through needle stick injuries can usually be avoided by following good working practices, health care workers should consider the implications of taking PEP. This will help them to make a swift decision in the event of an accident where an injury occurs.
WHERE NEXT?

AVERT.org has more about:
Page amended by Rob Noble & Gemma Spink, February 2008.
References:
- CDC (2006, December) ‘Surveillance of occupationally acquired HIV/AIDS in healthcare personnel, as of December 2006’ (modified 10th September 2007) accessed 17th January 2008.
- CDC (2007, September) 'Surveillance of occupationally acquired HIV/AIDS in healthcare personnel, as of December 2006' (modified 10th September 2007) Accessed 17th January 2008.
- BBC News (2008, 12th February) 'Nurse contracted HIV from patient'. Accessed 15th February 2008.
- Universal Precautions, Including Injection Safety, WHO, accessed September 2004.
Sources:
- HIV post-exposure prophylaxis: Guidance from the UK Chief Medical Officer's Expert Advisory Group on AIDS, 2nd edition, Department of Health, February 2004.


SIDA & VIH

