Seroprevalence of transfusion-transmissible infections and evaluation of the pre-donation screening performance at the Provincial Hospital of Tete, Mozambique.

BACKGROUND: The World Health Organization recommends universal and quality-controlled screening of blood donations for the major transfusion-transmissible infections (TTIs): human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis. The study objectives were to determine the seroprevalence of these TTIs among blood donors at the Provincial Hospital of Tete, Mozambique, and to assess the local pre-donation screening performance. METHODS: All consenting voluntary and replacement candidate blood donors were consecutively included from February to May 2009. Sera of all candidates, independent of deferral by questionnaire, were submitted to screening with quality-assured rapid or simple assays for HIV, HBV surface antigen (HBsAg), HCV and syphilis. Assays locally used by the blood bank for HBV and syphilis screening were run in parallel to quality-assured external assays supplied during the study, and all discordant samples were submitted to confirmation testing in reference laboratories in Mozambique and Belgium. RESULTS: Of 750 consenting candidates (50.5% of voluntary donors), 71 (9.5%) were deferred by the questionnaire, including 38 specifically because of risk behavior for TTI. Of the 679 non-deferred candidates, 127 (18.7%) had serological confirmation of at least one TTI, with a lower prevalence in voluntary than in replacement donors (15.2% versus 22.4%, p = 0.016). Seroprevalence of HIV, HBsAg and syphilis infections was 8.5%, 10.6 % and 1.2%. No confirmed HCV infection was found. Seroprevalence of TTIs was similar in the 38 candidates deferred for TTI risk as in the non-deferred group, except for HBsAg (26.3 % versus 10.6 %; p = 0.005). The local assays used for HBV and syphilis had sensitivities of 98.4% and 100% and specificities of 80.4% and 98.8% respectively. This resulted in the rejection of 110 of the 679 blood donations (16.2%) because of false positive results. CONCLUSIONS: The seroprevalence of TTIs after questionnaire screening is high in Tete, Mozambique, but HCV infection does not appear as a major issue. The questionnaire did not exclude effectively HIV-infected donor candidates, while the locally used assays led to unnecessary rejection of many safe donations. A contextualized questionnaire and consistent use of quality-assured assays would considerably improve the current screening procedure for blood donation.

Risk factors and true outcomes for lost to follow-up individuals in an antiretroviral treatment programme in Tete, Mozambique.

Scale-up of antiretroviral therapy (ART) in sub-Saharan Africa is a major public health priority, but ensuring long-term adherence to treatment is a growing concern. The objectives of this retrospective study were to determine risk factors and true outcomes for individuals lost to follow-up in a routine HIV/AIDS care programme in Tete, Mozambique. Between May 2002 and August 2007, 2818 individuals were initiated on ART and 594 (21%) considered lost to follow-up were actively traced. Risk factors for being lost to follow-up were: age between 16 and 35 years [odds ratio (OR) = 1.4, P = 0.009]; CD4 count <50 cells/µl (OR = 1.7, P < 0.001); time on ART <3 months (OR = 3.6, P < 0.001); tuberculosis infection (OR = 2.5, P < 0.001); and Kaposi's sarcoma infection (OR = 5.9, P < 0.001). Sixty-four percent (380/594) of patients lost to follow-up could not be traced. Of the 214 (36%) that could be traced, 118 (55%) were dead, 43 (20%) were transferred out, 7 (3%) were misclassified and 46 (22%) were true defaulters. Active tracing should be conducted routinely to better understand the reasons for defaulting and to provide evidence for action. Early mortality may be reduced by enrolling patients in care as early as possible and providing optimal adherence counselling in the first months.