Health care-associated hepatitis C virus infection

Hepatitis C virus(HCV)is a blood-borne pathogen that has a worldwide distribution and infects millions of people.Care-associated HCV infections represented a huge part of hepatitis C burden in the past via contaminated blood and unsafe injections and continue to be a serious problem of public health.The present review proposes a panorama of health care-associated HCV infections via the three mode of contamination that have been identified:(1)infected patient to non-infected patient;(2)infected patient to non-infected health careworker(HCW);and(3)infected HCW to non infected patient.For each condition,the circumstances of contamination are described together with the means to prevent them.As a whole,the more important risk is represented by unsafe practices regarding injections,notably with the improper use of multidose vials used for multiple patients.The questions of occupational exposures and infected HCWs are also discussed.In terms of prevention and surveillance,the main arm for combating care-associated HCV infections is the implementation of standard precautions in all the fields of cares,with training programs and audits to verify their good application.HCWs must be sensitized to the risk of blood-borne pathogens,notably by the use of safety devices for injections and good hygiene practices in the operating theatre and in all the invasive procedures.The providers performing exposed-prone procedures must monitor their HCV serology regularly in order to detect early any primary infection and to treat it without delay.With the need to stay vigilant because HCV infection is often a hidden risk,it can be hoped that the number of people infected by HCV via health care will decrease very significantly in the next years.

Is transfusion-transmitted dengue fever a potential public health threat?

Dengue is an arboviruses due to single-stranded enveloped ribonucleic acid viruses, named dengue viruses(DENV), that include four serotypes and are mainly transmitted via the bite of mosquitoes of the genus Aedes(A. aegypti and A. albopictus). The distribution of the disease was historically limited to intertropical areas; however, during the last thirty years, the perimeter of the disease extended considerably and temperate areas are now at risk of outbreaks. The present global burden of dengue is considerable: 2.5 billion people over more than 100 countries are concerned; 50 to 100 million infections occur every year, with a number of fatal cases of approximately 20000. Although frequently asymptomatic or limited to a mild fever, dengue is responsible for severe cases mainly consecutive to the occurrence of hemorrhagic complications that can lead to shock and death, notably in children from poorresource settings. The place of DENV as a transfusiontransmitted pathogen has been recognized only in 2008. At the present time, only five cases of transfusiontransmitted dengue, including one case of dengue hemorrhagic fever, have been formerly documented. This review provides a general overview of dengue, its viruses and their vectors. It replaces the disease in the context of other viral diseases transmitted by arthropods. It discusses the threat of dengue on the supply of blood products in endemic and non endemic areas. Finally, it describes the specific and non specific measures available for improving the security of blood products with regards to this emerging risk. Interestingly, in 2009, the American Association of Blood Banks placed DENV in the highest category of emerging infectious agents for their potential impact on transfusion recipient safety for the next years in North America.