RESUMO
Background: Hepatitis C Virus infection presents a major public health threat globally. The advent of different immunoassays for the detection of specific markers for the diagnosis of the infection since the discovery of the virus is a positive development, but their varied degrees of sensitivity and specificity is a matter of public health concern. Aim: To evaluate the efficiency of two commercial rapid test kits for the detection of anti- HCV antibodies against a third generation Enzyme Immunoassay (EIA) used as a gold standard. Methodology: A total of 500 patient plasma samples screened by ELISA (Autobio Diagnostics, China) were subjected to further screening using two rapid test (immuno chromatographic) strips supplied by Global Diagnostics (USA) and Wondfo Biotech Diagnostic Products (China). Results: Of the 500 samples, anti HCV was detected in 79(15.80%) by ELISA, 59(11.80%) by Wondfo strip, whereas only 45(9.00%) by Global strip method. This gave Wondfo Kit a sensitivity of 75.0%, specificity of 99.0%, overall accuracy of 95.2%, positive predictive value of 93.6%, negative predictive value of 95.4% positive likelihood ratio of 75.0, negative likelihood ratio of 0.25 and Kappa value of 0.803, while Global Kit had a sensitivity of 57.0%, specificity of 100.0%, overall accuracy of 93.2%, positive predictive value of 100%, negative predictive value of 92.5%, positive likelihood ratio of 0.57, negative likelihood ratio of 0.43 and Kappa value of 0.672. Conclusion: The result pattern reveals a marked or significant variation in sensitivity of the test kits. It is therefore recommended that third generation ELISA should be used for blood donors screening, to reduce transmission of hepatitis C virus through blood transfusion. Where the use of ELISA is practically unavailable in health facilities like in remote rural areas or poorest developing countries, the used of rapid strips can be adopted provided their performance are validated before its adoption. We recommend the use of PCR for detection of HCV RNA as a supplement to ELISA in laboratories or blood banks that can afford it.
RESUMO
Due to their potent toxicity; mycotoxins have attracted worldwide attention over the years and recently; there has been an increasing disquietness on the part of governments; producers; processors; marketers and consumers over the health and economic significance. The diversity in occurrence; structure and chemistry of mycotoxins make their impact more complex to diagnose. Owing to their usual environmental conditions of production in countries with warm and humid climates as well as poor conditions of storage and handling; agricultural commodities are susceptible to fungal colonization and development which can lead to the accumulation of mycotoxins. As part of drying process; agricultural produce are exposed to contamination by ubiquitous mycoflora that grow; develop and produce some toxic metabolites that are harmful to the consumers. Food is already a limited commodity; especially in developing countries of the world and consumers therefore; either as a matter of choice or for the relative cheapness and affordability during periods of scarcity; opt for the over-fresh produce; sometimes not aware of the adverse health implications such foods pose. In the quest to ensure regular and continuous availability of certain perishable farm produce; especially in developing nations; local farmers and traders resort to unscientific and faulty storage conditions to preserve commodities; thereby pre-disposing produce to fungal colonization and mycotoxin production. Thus; commodities such as groundnuts; maize; sorghum; rice; yam; cassava; tiger nut; soyabeans; cotton seeds; fruits; vegetables spices can be contaminated with toxins of fungal origin such as aflatoxins; ochratoxins; fumonisins; patulin; sterigmatocystin; deoxynivalenol; zearalenone and other mycotoxins which pose serious economic and health risks. This review presents some mycotoxins commonly found on agricultural commodities both in temperate and tropic regions of the world. The acute and chronic toxic effects of these toxins in humans and animals are highlighted. Control measures include education of the populace on the risks of exposure to mycotoxins through skin contact; inhalation and ingestion; early harvesting; rapid appropriate drying; sequestration of diseased seeds from sound seeds; sanitation; use of good agronomic practices; insect control; the use of botanicals and synthetics as storage protectants; biological control and detoxification of mycotoxin-contaminated commodities. Probable related health implications are also discussed with a view to creating better public awareness and providing scientific basis for appreciating the challenges; while proactively promoting the development and implementation of policies at mitigating risk factors. Some mycotoxins; their producer fungi and toxic effects are further presented