@article{fdi:010046345,
  title = {{A}ssessment of the relative success of sporozoite inoculations in individuals exposed to moderate seasonal transmission},
  author = {{T}all, {A}. and {S}okhna, {C}heikh and {P}erraut, {R}. and {F}ontenille, {D}idier and {M}arrama, {L}. and {L}y, {A}. {B}. and {S}arr, {F}. {D}. and {T}oure, {A}. and {T}rape, {J}ean-{F}ran{\c{c}}ois and {S}piegel, {A}. and {R}ogier, {C}. and {D}ruilhe, {P}.},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground: {T}he time necessary for malaria parasite to re-appear in the blood following treatment (re-infection time) is an indirect method for evaluating the immune defences operating against pre-erythrocytic and early erythrocytic malaria stages. {F}ew longitudinal data are available in populations in whom malaria transmission level had also been measured. {M}ethods: {O}ne hundred and ten individuals from the village of {N}diop ({S}enegal), aged between one and 72 years, were cured of malaria by quinine (25 mg/day oral {Q}uinimax {T} in three equal daily doses, for seven days). {T}hereafter, thick blood films were examined to detect the reappearance of {P}lasmodium falciparum every week, for 11 weeks after treatment. {M}alaria transmission was simultaneously measured weekly by night collection of biting mosquitoes. {R}esults: {M}alaria transmission was on average 15.3 infective bites per person during the 77 days follow up. {T}he median reappearance time for the whole study population was 46.8 days, whereas individuals would have received an average one infective bite every 5 days. {A}t the end of the follow-up, after 77 days, 103 of the 110 individuals (93.6%; {CI} 95% [89.0-98.2]) had been re-infected with {P}. falciparum. {T}he median reappearance time ('re-positivation') was longer in subjects with patent parasitaemia at enrolment than in parasitologically-negative individuals (58 days vs. 45.9; p = 0.03) and in adults > 30 years than in younger subjects (58.6 days vs. 42.7; p = 0.0002). {I}n a multivariate {C}ox {PH} model controlling for the sickle cell trait, {G}6{PD} deficiency and the type of habitat, the presence of parasitaemia at enrolment and age >= 30 years were independently predictive of a reduced risk of re-infection ({PH} = 0.5 [95% {CI}: 0.3-0.9] and 0.4; [95% {CI}: 0.2-0.6] respectively). {C}onclusion: {R}esults indicate the existence of a substantial resistance to sporozoites inoculations, but which was ultimately overcome in almost every individual after 2 1/2 months of natural challenges. {S}uch a study design and the results obtained suggest that, despite a small sample size, this approach can contribute to assess the impact of intervention methods, such as the efficacy vector-control measures or of malaria pre-erythrocytic stages vaccines.},
  keywords = {},
  booktitle = {},
  journal = {{M}alaria {J}ournal},
  volume = {8},
  numero = {},
  pages = {161},
  ISSN = {1475-2875},
  year = {2009},
  DOI = {10.1186/1475-2875-8-161},
  URL = {https://www.documentation.ird.fr/hor/fdi:010046345},
}