Vito Scalia

Current incidence and estimated residual risk of transfusion-transmitted infections in donations made to Canadian Blood Services

BACKGROUND: New testing methods such as nucleic acid amplification testing (NAT) and chemiluminescent serologic assays have been introduced, more precise estimates for infectious window periods are available, and a new method for estimating the residual risk (RR) of transfusion‐transmitted infections (TTIs) has been developed. Thus, available RR estimates for Canada need to be updated.

Current incidence and residual risk of HIV, HBV and HCV at Canadian Blood Services

Estimates of the viral residual risk should be updated to reflect current incidence of infection in blood donors. Incidence rates were estimated for allogeneic whole‐blood donations made to Canadian Blood Services from 2006 to 2009 based on transmissible disease conversions of repeat donations within a 3‐year period. Residual risk was estimated as the incidence multiplied by the window period. The residual risk of HIV was 1 per 8 million donations, HCV 1 per 6·7 million donations and HBV 1 per 1·7 million donations. The residual risk remains low and has decreased for HCV since our previous estimates due to reduced incidence.

Hepatitis B virus DNA–positive, hepatitis B surface antigen–negative blood donations intercepted by anti‐hepatitis B core antigen testing: the Canadian Blood Services experience

BACKGROUND: The benefit of introducing anti‐hepatitis B core antigen (HBc) screening for intercepting potentially infectious donations missed by hepatitis B surface antigen (HBsAg) screening in Canada was studied.

Iron deficiency in Canadian blood donors

The adequacy of communication and knowledge of donors and physicians regarding iron needs and the relationship between hemoglobin (Hb) and iron stores require evaluation to address donor iron deficiency.

Epidemiology of hepatitis B in Canadian blood donors

BACKGROUND: The residual risk of hepatitis B is higher than for other markers such as human immunodeficiency virus and hepatitis C virus in nonendemic countries. Evaluating the potential for further risk reduction requires a better understanding of the relationship between donor selection criteria, immigration from endemic countries, and public health vaccination strategies.

Screening of Canadian Blood Services donors for severe immunoglobulin A deficiency

BACKGROUND: Immunoglobulin A (IgA)‐deficient patients with antibodies to IgA require transfusions with IgA‐deficient blood components to either avoid or reduce the frequency of serious adverse reactions. To supply compatible blood components for these individuals, the Canadian Blood Services (CBS) National Testing Laboratory must initially screen and subsequently identify, after confirmatory testing at the American Red Cross (ARC), donors severely deficient in IgA (<0.05 mg/dL).

Flow cytometric determination of residual white blood cell levels in preserved samples from leukoreduced blood products.

BACKGROUND: In preparation for a proposed consolidated testing service, Canadian Blood Services undertook the evaluation of a commercial test kit for the enumeration by flow cytometry of residual white blood cells (rWBCs) present in preserved samples recovered from leukoreduced (LR) blood and platelet products.

Assessment of a travel question to identify donors with risk of Trypanosoma cruzi: operational validity and field testing

BACKGROUND: Because Trypanosoma cruzi (T. cruzi) infection in Canada and the United States is largely contracted in endemic countries, targeted testing of blood donors with risk travel may improve safety. The operational validity of a travel question suitable for donor screening was tested, and it was field‐tested.

A Case of Vertical Transmission of Chagas Disease Contracted via Blood Transfusion in Canada

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and is endemic in many countries in Latin America, where infected bugs of the Triatominea subfamily carry the parasite in the gut and transmit it to humans through fecal contamination of a bite. However, vertical transmission and transmission through blood transfusion and organ transplantation is well documented. Increasing immigration from endemic countries to North America has prompted blood operators, including Canadian Blood Services and Hema Quebec, to initiate blood donor testing for Chagas antibody. In the present report, an unusual case of vertical transmission from a mother, most likely infected through blood transfusion, and detected as part of a concurrent seroprevalence study in blood donors is described.

A large national study of ferritin testing in Canadian blood donors

We assessed risk groups for iron deficiency and the feasibility and efficacy of ferritin testing in a large blood center.