title: Haemagglutination-inhibiting variola antibodies in blood serum of former smallpox patients, their healthy siblings, and unvaccinated controls from other areas.
mesh_terms: D000906:Antibodies / Q000032:analysis*; D000937:Antigen-Antibody Reactions; D001789:Blood Group Antigens; D004196:Disease Outbreaks; D005190:Family; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007194:India; D012424:Rural Population; D012899:Smallpox / Q000453:epidemiology; D014611:Vaccination; D012901:Variola virus / Q000276:immunology*
chemical_list: D000906:Antibodies; D001789:Blood Group Antigens