Clinical observations on smallpox: a study of 1233 patients admitted to the Infectious Diseases Hospital, Calcutta, during 1973.

The paper presents clinical observations on 1 233 persons with smallpox who were admitted to the Infectious Diseases Hospital, Calcutta, in 1973. The disease was of the modified type in 53 patients (4.3%), the ordinary type in 717 (58.2%), the flat type in 249 (20.2%), and the haemorrhagic type in 214 (17.3%). The fatality of these types of smallpox was found to be 5.7%, 26.8%, 88.4%, and 98.1%, respectively, and the overall case fatality was 50.7%. The haemorrhagic type was found mainly among older patients and affected males more often than females. The vaccination status of 1 218 patients was known. Of these, 901 (73.9%) were unvaccinated and had a fatality rate of 53.4%, whereas the 317 (26.1%) vaccinated patients had a fatality rate of 36.5%. Among the 201 haemorrhagic cases, 145 patients were unvaccinated (16.09% of the total number unvaccinated) and 56 (17.67%) had been vaccinated. Of 34 patients vaccinated during the incubation period, 19 (41.1%) died, whereas of 18 patients who had been vaccinated after the onset of fever, but before the appearance of rash, 9 (50%) died.