Laboratory diagnosis of smallpox: role of the Virus Reference Laboratory, Colindale, 1947-70.

The Virus Reference Laboratory, Colindale, first embarked on laboratory investigations for smallpox early in 1947. From then, in conjunction with the Department of Bacteriology, University of Liverpool, it provided a complete diagnostic service throughout England and Wales until 1962, after which the service became available regionally until eradication was effected. Up to 1970 it had investigated 2696 specimens from suspected cases of smallpox and had recovered 108 strains of variola and 248 of vaccinia virus. These last were from persons suffering the complications of vaccination. Some outbreaks following smallpox importation are discussed but infection among laboratory staff during this period was not demonstrated.