there is a more than 90 percantage chance of getting
hiv through blood transfusion either he had undetectable viral load or not because these viruses are in window period so we can't detect viral load
Next Steps
if u know that they had transfused
hiv infected blood then within 72 hours or i say within 24 hours you take prophylaxis medication then there is more than 99 percantage that you will not get infection