Following host DNA degradation, is responsible for the degradation of 5'-dNMP's to deoxynucleosides that can be further excreted (PubMed:335083). Active on deoxynucleoside 5'-monophosphates but not active as a phosphatase on ribonucleotides, deoxynucleoside 5'-triphosphates, deoxynucleoside 3'-monophosphates, or deoxyoligonucleotides (PubMed:21305). a 2'-deoxyribonucleoside 5'-phosphate + H2O = a 2'-deoxyribonucleoside + phosphate Expressed pre-early in the viral replicative cycle. Expressed with a few other proteins from the first step transfer (FST) DNA. FST DNA corresponds to the first small portion of the genome that enters into the host cell at the beginning of infection before pausing. This gene is part of the long terminal repeats present at both ends of the viral genome and is thus duplicated.