Group O Human Immunodeficiency Virus Type 1 Infection That Escaped Detection in Two Immmunoassays

Abstract
We report a case of human immunodeficiency virus type 1 group O infection not detected by two highly sensitive immunoassays. The sera were strongly reactive to the V3 peptide of group O but not to the gp41 immunodominant epitope. Gp41 was sequenced, confirming that this virus belonged to group O.