Immunological memory after exposure to variola virus, monkeypox virus, and vaccinia virus

UMMS Affiliation

Department of Medicine, Division of Infectious Diseases and Immunology; Center for Infectious Disease and Vaccine Research

Publication Date


Document Type



Immunity | Immunology and Infectious Disease | Immunology of Infectious Disease | Infectious Disease


We compared cellular and humoral immunity to vaccinia virus (VV) in individuals exposed to 3 different orthopoxviruses: 154 individuals previously vaccinated with VV, 7 individuals with a history of monkeypox virus infection, and 8 individuals with a history of variola virus infection. Among individuals vaccinated > 20 years prior, 9 (14%) of 66 individuals demonstrated VV-specific interferon (IFN)- gamma enzyme-linked immunospot (ELISPOT) assay responses; 21 (50%) of 42 had lymphoproliferative (LP) responses, and 29 (97%) of 30 had VV-specific neutralizing antibodies. One year after monkeypox virus infection, 6 of 7 individuals had IFN- gamma ELISPOT responses, all had VV-specific LP responses, and 3 of 7 had VV-specific neutralizing antibodies. Of 8 individuals with a history of variola virus infection, 1 had a VV-specific IFN- gamma ELISPOT response, 4 had LP responses against whole VV, 7 had LP responses against heat-denatured vaccinia antigen, and 7 had VV-specific neutralizing antibodies. Survivors of variola virus infection demonstrated VV-specific CD4 memory cell responses and neutralizing antibodies > 40 years after infection.

DOI of Published Version



J Infect Dis. 2007 Apr 15;195(8):1151-9. Epub 2007 Mar 5. DOI: 10.1086/512161 Link to article on publisher's site

Journal/Book/Conference Title

The Journal of infectious diseases

Related Resources

Link to Article in PubMed

PubMed ID