“…After healing of an infection caused by a TK-negative drug-resistant HSV strain and stopping antiviral therapy, recurrences are most often associated with a drugsensitive strain, although some cases of spontaneous recurrences of ACV-resistant viruses have been reported (1,78,100,113,125,126,142,146,152,153,178,201,205,232,246). Laboratory diagnosis of ACV resistance is required to guide clinicians toward different treatment options in cases of therapy failure.…”