Risk of AIDS From Needle Pricks

The risk of AIDS via needle prick injuries was exaggerated by Andre⁄ Picard ("A tiny pinprick, a deadly outcome" December 1, 2003, page A1,A6). According to Health Canada, there have only been 6 cases of AIDS due to occupational exposure in Canada over a time where there have probably been well over one million needle prick injuries.[1] Limited information has been published, but in the first case, an elderly woman, the conclusion was drawn not from positive evidence, but by the elimination of all other possible explanations. The possibility of false positive test results was not considered.

In the United States, with almost a million AIDS cases diagnosed, the CDC no longer bothers to report the number of health care workers with documented transmission of HIV (let alone AIDS).[2] Up to 1997, the last year this information was reported, only 25 cases of AIDS out of 633,000  had been blamed on documented occupational transmission. There was not a single case among paramedics and surgeons, two groups most likely to have uncontrolled exposures to HIV-positive blood.

Health care workers who are exposed to blood that is suspected to be HIV-positive are treated with drugs that have potentially fatal consequences. One US health care worker had a life-threatening allergic reaction,[4] and another required a liver transplant after post-exposure prophylaxis, for example.[5]

The case of Brenda Tippett, and others like it, are certainly unfortunate, but she may well be suffering from drug-induced injury, not from HIV and Hepatitis C.


References:
[1] HIV and AIDS in Canada: Surveillance report to December 31, 2002. Health Canada. 2003 Apr.

[2] HIV/AIDS Surveillance Report; U.S. HIV and AIDS cases reported through December 2001. CDC. 2002; 13(2).

[3] HIV/AIDS Surveillance Report (through December 1997). CDC. 1998; 9(2).

[4] Johnson S et al. Adverse Effects Associated With Use of Nevirapine in HIV Postexposure Prophylaxis for 2 Health Care Workers [first case]. JAMA. 2000 Dec 6.

[5] Sha BE et al. Adverse Effects Associated With Use of Nevirapine in HIV Postexposure Prophylaxis for 2 Health Care Workers [second case]. JAMA. 2000 Dec 6; 284(21): 2723.

Questions that should have been asked (and answered) about SARS before we panicked…

(Unpublished letter to the Globe and Mail)

Questions that should  have been asked (and answered) about SARS before we panicked:

• Do relatively vague symptoms (high temperature, plus one of a number of respiratory symptoms, including cough) necessarily indicate a single pathogen?
• How were environmental causes or co-factors eliminated from consideration?
• Why do "SARS" symptoms in a person with no known direct or indirect contact with someone from Southeast Asia not result in a diagnosis of SARS?
• Have people recently arrived from the far east never come down with these symptoms shortly  after arriving in Canada before?
• Were extra 'potent' pharmaceuticals, including antibiotics, prescribed once it was feared that a new pathogen was present?
• How can a test be known to be reliable when the pathogen that it is testing for is still unknown?
• Why have the media not asked these questions (or at least not published them, with corresponding answers, anywhere)?

Are we in fact witnessing an artificial phenomenon, where public health officials have realized that under-reacting to a potential threat is career suicide, yet over-reacting to a threat has minimal consequences, and might even make them look heroic?

Reference: SARS Case Definition

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David Crowe