a severe or even fatal form of vaccinia that occurs mainly in persons with an immunological deficiency; characterized by progressive enlargement of the initial lesion (noun.state)
a local infection induced in humans by inoculation with the virus causing cowpox in order to confer resistance to smallpox; normally lasts three weeks more.. a local infection induced in humans by inoculation with the virus causing cowpox in order to confer resistance to smallpox; normally lasts three weeks and leaves a pitted scar (noun.state)