As Padval and Shah point out in their correspondence, human to human transmission of orthopoxviruses is possible in principle. This has been confirmed by several publications for variola and vaccinia viruses ([1, 2] in Padval’s letter), buffalopoxvirus ([3] in Shah’s letter), and monkeypox virus (4). However, for the independent species cowpox virus, no human to human transmission has been reported in the literature so far, and we have not observed any cases.
In view of the known transmission potential of other orthopoxvirus species and the well known transmission potential of cowpox viruses in animals of the same species and across the species barrier, as well as of the contact infection we described in our article—from a patient’s abdomen to their own eye—we certainly think that human to human transmission of cowpox is possible.
Footnotes
Conflict of interest statement
The author declares that no conflict of interest exists according to the guidelines of the International Committee of Medical Journal Editors.
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