Can a blood test be done to detect strep throat infection?
Streptococcus infection can be detected by measuring the antibodies produced by the body against the bacteria. This is called the Anti-streptolysin O or ASO titer. This antibody may not be present in the blood for a few weeks after an infection, and therefore its measurement may not be accurate to detect an active or acute infection. ASO titers also may not be detectable if the person had been appropriately treated with antibiotics. This test may be useful in evaluating a person with complications of strep throat infection such as rheumatic fever or glomerulonephritis (see below).
