Serological Immunity to Smallpox in New South Wales, Australia

The re-emergence of smallpox is an increasing and legitimate concern due to advances in synthetic biology. Vaccination programs against smallpox using the vaccinia virus vaccine ceased with the eradication of smallpox and, unlike many other countries, Australia did not use mass vaccinations. However...

Full description

Saved in:
Bibliographic Details
Published in:Viruses 2020-05, Vol.12 (5), p.554
Main Authors: Costantino, Valentina, Trent, Mallory J, Sullivan, John S, Kunasekaran, Mohana P, Gray, Richard, MacIntyre, Raina
Format: Article
Language:English
Subjects:
Adult
Age
Antibodies
Antibodies, Neutralizing - blood
Antibodies, Viral - blood
Blood & organ donations
Cell-mediated immunity
Dosage and administration
Epidemics
Female
Herd immunity
Humans
Humoral immunity
Immunity (Physiology)
Immunity, Herd
Immunological memory
Infections
Male
Medical research
Middle Aged
New South Wales - epidemiology
Outbreaks
Patient outcomes
Plasmapheresis
Population
population immunity
Prevention
response planning
Seroepidemiologic Studies
Serology
Smallpox
Smallpox - blood
Smallpox - epidemiology
Smallpox - immunology
Smallpox - prevention & control
Smallpox Vaccine - administration & dosage
Smallpox Vaccine - immunology
Studies
Time Factors
Vaccination
vaccine immunity
Vaccines
Vaccinia virus - immunology
Viral vaccines
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The re-emergence of smallpox is an increasing and legitimate concern due to advances in synthetic biology. Vaccination programs against smallpox using the vaccinia virus vaccine ceased with the eradication of smallpox and, unlike many other countries, Australia did not use mass vaccinations. However, vaccinated migrants contribute to population immunity. Testing for vaccinia antibodies is not routinely performed in Australia, and few opportunities exist to estimate the level of residual population immunity against smallpox. Serological data on population immunity in Australia could inform management plans against a smallpox outbreak. Vaccinia antibodies were measured in 2003 in regular plasmapheresis donors at the Australian Red Cross Blood Service from New South Wales (NSW). The data were analysed to estimate the proportion of Australians in NSW with detectable serological immunity to vaccinia. The primary object of this study was to measure neutralising antibody titres against vaccinia virus. Titre levels in donor samples were determined by plaque reduction assay. To estimate current levels of immunity to smallpox infection, the decline in geometric mean titres (GMT) over time was projected using two values for the antibody levels estimated on the basis of different times since vaccination. The results of this study suggest that there is minimal residual immunity to the vaccinia virus in the Australian population. Although humoral immunity is protective against orthopoxvirus infections, cell-mediated immunity and immunological memory likely also play roles, which are not quantified by antibody levels. These data provide an immunological snapshot of the NSW population, which could inform emergency preparedness planning and outbreak control, especially concerning the stockpiling of vaccinia vaccine.
ISSN:1999-4915
1999-4915
DOI:10.3390/v12050554