Catpox

Via ProMED-mail: Eurosurveillance surveys recent (human) cowpox cases in Germany, increasingly via cats, and speculates on the cause:

Before the global eradication of smallpox (announced by the World Health Organization in 1979), live vaccinia virus was commonly used as a vaccine against variola virus. Vaccinia virus is closely related to variola virus and other members of the orthopoxviruses and induces cross-immunity [13]. In the course of the eradication of variola virus, vaccinations of children were stopped in Germany in the 1970s due to severe vaccination-related complications. Thus, there is a widening immunisation gap in a population that was previously protected by this vaccine not only against smallpox, but also had an inprecisely defined protection against other forms of orthopoxviruses, e.g. cowpox and monkeypox. Over the last two years, nine patients suspected of suffering from poxvirus infection were examined at the German consultant laboratory for poxviruses. Four of the patients, including the two cases described above, were positive for cowpox virus. [...] This represents an increase in diagnosed human cowpox infections in Germany during the past years. Whilst it cannot be excluded that this is due to a reporting bias, this increase may reflect the fact that a smaller proportion of people have immunity against cowpox virus after the stop of smallpox vaccinations. Interestingly, recent human cowpox cases were observed in people too young to be vaccinated against smallpox.