[Transmission of hepatitis C by accidental needlestick injuries. Evaluation of the risk]

The risk of transmitting contagious diseases by accidental needle-stick injury has raised a considerable amount of concern among hospital staff. Before generalized vaccination in the early 80s, there was a high risk of hepatitis B transmission. More recently, the development of reliable techniques of detecting serum markers has made it possible to precisely evaluate the risk for hepatitis C. The risk of contamination by the hepatitis C virus by accidental needle-stick injury can be estimated at 0 to 3%, and can only reach a maximum of 10% when the patient is positive for hepatitis C RNA. The risk is thus less than for hepatitis B virus (7 to 30%). The low rate of transmission probably results from the quantity of viral material in blood and secretions. In populations of health personnel exposed to a risk of septic needle-stick injury, the prevalence of anti-hepatitis C virus antibodies has been observed in several studies at rates between 0 and 2%. This is similar to non-exposed populations and would be an argument suggesting that there is a low risk of hepatitis C virus transmission. Nevertheless, because hospital staff is frequently exposed to blood and because a significant number of patients are positive for anti-hepatitis C virus antibodies, adequate preventive measures must be taken. The Immunization Practice Advisory Committee (USA) recommends injection of polyvalent gammaglobulins when stick injury occurs with a needle used for a hepatitis C virus antibody positive patient, but the effectiveness of this protocol has not been demonstrated. Several preliminary studies suggest that treatment of hepatitis C in the acute phase could significantly reduce the rate of chronicity. When interferon has been authorized for this indication, and if effectiveness is confirmed, treatment might be recommended for health personnel with acute needle-stick transmitted HCV infection. Infected needle-stick victims might be followed by having their transaminases checked 4-12 weeks later. In case of positive results, early interferon therapy might be started.