Abstract |
We calculated the number and growth rate of Plasmodium falciparum parasites emerging in recipients of candidate preerythrocytic malaria vaccines and unvaccinated control subjects undergoing mosquito- bite challenge. This was done to measure vaccine efficacy and to distinguish the effects on blood-stage multiplication from those on liver-stage parasites. Real-time polymerase chain reaction measurements of parasite densities were analyzed by nonlinear regression and mixed-effects models. Substantial reductions in numbers of liver parasites resulted from the use of 2 immunization regimens: FP9 boosted by modified virus Ankara (MVA) encoding the malaria epitope- thrombospondin-related adhesion protein insert (92% reduction) and RTS,S/AS02 used in heterologous prime-boost immunization regimens, with MVA encoding the circumsporozoite protein (97% reduction). Forty-eight-hour growth rates in blood from control subjects were not different from those in blood from any vaccination group (mean, 14.4-fold [95% confidence interval, 11-19-fold]).
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Authors | Philip Bejon, Laura Andrews, Rikke F Andersen, Susanna Dunachie, Daniel Webster, Michael Walther, Sarah C Gilbert, Tim Peto, Adrian V S Hill |
Journal | The Journal of infectious diseases
(J Infect Dis)
Vol. 191
Issue 4
Pg. 619-26
(Feb 15 2005)
ISSN: 0022-1899 [Print] United States |
PMID | 15655787
(Publication Type: Clinical Trial, Controlled Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antigens, Protozoan
- DNA, Protozoan
- Malaria Vaccines
- Vaccines, Synthetic
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Topics |
- Animals
- Antigens, Protozoan
(genetics, immunology)
- Bayes Theorem
- Blood
(parasitology)
- DNA, Protozoan
(analysis)
- Humans
- Liver
(parasitology)
- Malaria
(immunology, parasitology, prevention & control)
- Malaria Vaccines
(administration & dosage, immunology)
- Markov Chains
- Models, Biological
- Models, Statistical
- Nonlinear Dynamics
- Plasmodium falciparum
(growth & development, immunology, isolation & purification)
- Polymerase Chain Reaction
- Regression Analysis
- Sporozoites
(growth & development)
- Vaccination
- Vaccines, Synthetic
(administration & dosage, immunology)
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