Self-boosting vaccines and their implications for herd immunity
- 19 November 2012
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 109 (49), 20154-20159
- https://doi.org/10.1073/pnas.1209683109
Abstract
Advances in vaccine technology over the past two centuries have facilitated far-reaching impact in the control of many infections, and today's emerging vaccines could likewise open new opportunities in the control of several diseases. Here we consider the potential, population-level effects of a particular class of emerging vaccines that use specific viral vectors to establish long-term, intermittent antigen presentation within a vaccinated host: in essence, "self-boosting" vaccines. In particular, we use mathematical models to explore the potential role of such vaccines in situations where current immunization raises only relatively short-lived protection. Vaccination programs in such cases are generally limited in their ability to raise lasting herd immunity. Moreover, in certain cases mass vaccination can have the counterproductive effect of allowing an increase in severe disease, through reducing opportunities for immunity to be boosted through natural exposure to infection. Such dynamics have been proposed, for example, in relation to pertussis and varicella-zoster virus. In this context we show how self-boosting vaccines could open qualitatively new opportunities, for example by broadening the effective duration of herd immunity that can be achieved with currently used immunogens. At intermediate rates of self-boosting, these vaccines also alleviate the potential counterproductive effects of mass vaccination, through compensating for losses in natural boosting. Importantly, however, we also show how sufficiently high boosting rates may introduce a new regime of unintended consequences, wherein the unvaccinated bear an increased disease burden. Finally, we discuss important caveats and data needs arising from this work.Keywords
This publication has 48 references indexed in Scilit:
- First Results of Phase 3 Trial of RTS,S/AS01 Malaria Vaccine in African ChildrenNew England Journal of Medicine, 2011
- Basigin is a receptor essential for erythrocyte invasion by Plasmodium falciparumNature, 2011
- Synthesizing epidemiological and economic optima for control of immunizing infectionsProceedings of the National Academy of Sciences of the United States of America, 2011
- Profound early control of highly pathogenic SIV by an effector memory T-cell vaccineNature, 2011
- Natural immune boosting in pertussis dynamics and the potential for long-term vaccine failureProceedings of the National Academy of Sciences of the United States of America, 2011
- Mucosal host immune response predicts the severity and duration of herpes simplex virus-2 genital tract shedding episodesProceedings of the National Academy of Sciences of the United States of America, 2010
- Cytomegalovirus Infection- and Age-Dependent Changes in Human CD8 + T-Cell Cytokine Expression PatternsClinical and Vaccine Immunology, 2010
- Evasion of CD8 + T Cells Is Critical for Superinfection by CytomegalovirusScience, 2010
- The effect of opinion clustering on disease outbreaksJournal of The Royal Society Interface, 2008
- Ability of herpes simplex virus vectors to boost immune responses to DNA vectors and to protect against challenge by simian immunodeficiency virusVirology, 2007