ABH Substances Secretion Status, ABO & Rhesus Blood Groups Typing and P24 Antigen Screening in HIV 1 and 2 Screened Antibody-negative Apparently Healthy Prospective Blood Donors in Calabar, Nigeria

Aim: To investigate ABH Secretion status, ABO/ Rhesus blood groups and P24 antigen in 400 HIV screened antibody-negative apparently healthy prospective blood donors aged above 20 years recruited within Calabar, Nigeria.

Study Design: experimental, work carried out in the Haematology & Blood Transfusion Unit, Department of Medical Lab Science,University of Calabar Nigeria between December 2009 and December 2010.

Methods and Materials: About 5ml of blood and 3ml of saliva samples were collected by standard procedures from 400 consented selected subjects prior to selection and sera were serologically screened for HIV 1& 2 antibodies using Stat Pak , Determine and Unigold test Kits ,while HIV 1 & 2 antigens were screened using HIV1 and 2 P24 antigens Combi test Kit. Saliva samples analysed for ABH secretor status using BIOTECH Anti-H reagent. ABO/Rhesus blood groups typing were done using blood grouping Anti -sera (A, B, AB, & D) reagents and known red blood cells.

Results: Only 10 samples (02.5 %) reacted positively to the HIV antibody screening panel with two samples (0.2%) out of the 10 samples reacted positive to HIV P24 antigens screening kit. About 11 samples (2.82%) from the tested HIV antibody-negative samples reacted positively to HIV P24 antigens screening kit with 13 positive samples (3.25%). 317 samples (79.25%) were ABH Substance secretors and 83 samples (20.75%) were non-secretors. 4 samples (1%) that were HIV P24 positive were also positive for non-secretor while 9 samples (2.25%) that were positive to P24 antigen screening test were also secretor.

The order positive results of P24 antigens screening amongst ABO/Rhesus blood groups positive samples were 2(.5%) for A+ , 4(1%)for B+, 7(1.75%) for O+. A significant statistical difference exists between HIV Antibody and HIV P24 antigen tests (P<0.5). Chi-Square X2 test shows positive relationship between HIV P24 antigen screening, secretor status, ABO and Rhesus typing results (P<0.5).

Conclusion: ABH Substance secretors were less susceptible to HIV 1 and 2 P24 antigens screened positive test than ABH Substance non-secretors. Blood group O+ subjects are predisposed to HIV 1 and 2 P 24 antigens screened positive test than A+ ,B+, AB+, and Rhesus D negative subjects . The risk of infected HIV antibody-negative blood donors has been implicated with a prevalence rate of 3.3%.