Common warts from immunocompetent patients show the same distribution of human papillomavirus types as common warts from immunocompromised patients.

We studied the papillomaviruses (HPV) found in 131 common warts from 111 immunocompetent patients by amplification of viral DNA sequences with the general-primer-mediated polymerase chain reaction (PCR). The virus types were determined by restriction-enzyme cleavage and reverse-blot analysis. Results were confirmed by using the Southern blot technique. Forty patients harboured HPV 2a, 25 individuals showed HPV 2c and 13 yielded HPV 57. Common warts from 16 patients were induced by a variant of HPV 57. HPV 7 was found in four patients. HPV 1 was identified in two patients, and there was evidence for HPV 4 in only one case. One individual yielded an HPV type which was only weakly related to HPV 2. Three patients were infected by more than one HPV type. PCR did not demonstrate HPV-DNA in warts from six individuals. The distribution and variation of HPV types found in the common warts of immunocompetent patients were similar to the findings in immunocompromised patients reported by other authors.