Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2008 Aug 1:7:147.
doi: 10.1186/1475-2875-7-147.

A quantitative risk assessment approach for mosquito-borne diseases: malaria re-emergence in southern France

Nicolas Ponçon  1 , Annelise Tran, Céline Toty, Adrian Jf Luty, Didier Fontenille
Affiliations

A quantitative risk assessment approach for mosquito-borne diseases: malaria re-emergence in southern France

Nicolas Ponçon et al. Malar J. .

Abstract

Background: The Camargue region is a former malaria endemic area, where potential Anopheles vectors are still abundant. Considering the importation of Plasmodium due to the high number of imported malaria cases in France, the aim of this article was to make some predictions regarding the risk of malaria re-emergence in the Camargue.

Methods: Receptivity (vectorial capacity) and infectivity (vector susceptibility) were inferred using an innovative probabilistic approach and considering both Plasmodium falciparum and Plasmodium vivax. Each parameter of receptivity (human biting rate, anthropophily, length of trophogonic cycle, survival rate, length of sporogonic cycle) and infectivity were estimated based on field survey, bibliographic data and expert knowledge and fitted with probability distributions taking into account the variability and the uncertainty of the estimation. Spatial and temporal variations of the parameters were determined using environmental factors derived from satellite imagery, meteorological data and entomological field data. The entomological risk (receptivity/infectivity) was calculated using 10,000 different randomly selected sets of values extracted from the probability distributions. The result was mapped in the Camargue area. Finally, vulnerability (number of malaria imported cases) was inferred using data collected in regional hospitals.

Results: The entomological risk presented large spatial, temporal and Plasmodium species-dependent variations. The sensitivity analysis showed that susceptibility, survival rate and human biting rate were the three most influential parameters for entomological risk. Assessment of vulnerability showed that among the imported cases in the region, only very few were imported in at-risk areas.

Conclusion: The current risk of malaria re-emergence seems negligible due to the very low number of imported Plasmodium. This model demonstrated its efficiency for mosquito-borne diseases risk assessment.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Risk of malaria re-emergence.
Figure 2
Figure 2
Entomological factors.
Figure 3
Figure 3
Probability distributions.
Figure 4
Figure 4
Spatial distribution of the human biting rate in the Camargue in August. Classes were arbitrary chosen with a logarithmic scale.
Figure 5
Figure 5
Distribution of An. hyrcanus anthropophily.
Figure 6
Figure 6
Distribution of the length, in days, of the trophogonic cycle in August.
Figure 7
Figure 7
Distribution of the An. hyrcanus daily survival rate.
Figure 8
Figure 8
Distribution of An. hyrcanus susceptibility to P. falciparum.
Figure 9
Figure 9
Distribution of An. hyrcanus susceptibility to P. vivax.
Figure 10
Figure 10
Spatial variations of P. falciparum transmission risk estimate (ranging from 0 to more than 1) in June in the Camargue. Classes were arbitrary chosen with a logarithmic scale.
Figure 11
Figure 11
Spatial variations of P. falciparum transmission risk estimate (ranging from 0 to more than 1) in July in the Camargue. Classes were arbitrary chosen with a logarithmic scale.
Figure 12
Figure 12
Spatial variations of P. falciparum transmission risk estimate (ranging from 0 to more than 1) in August in the Camargue. Classes were arbitrary chosen with a logarithmic scale.
Figure 13
Figure 13
Spatial variations of P. falciparum transmission risk estimate (ranging from 0 to more than 1) in September in the Camargue. Classes were arbitrary chosen with a logarithmic scale.
Figure 14
Figure 14
Spatial variations of the P. vivax transmission risk estimate (ranging from 0 to more than 100) in August in the Camargue. Classes were arbitrary chosen with a logarithmic scale.
Figure 15
Figure 15
Sensitivity analysis.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Rodhain F, Charmot G. Evaluation des risques de reprise de transmission du paludisme en France. Med Mal Infect. 1982;12:231–236.
    1. Sautet J. A propos d'une épidémie de paludisme en Camargue. Mars Med. 1944;2:53–64.
    1. Balenghien T, Fouque F, Sabatier P, Bicout DJ. Horse, bird, and human-seeking behavior and seasonal abundance of mosquitoes in a West Nile virus focus of southern France. J Med Entomol. 2006;43:936–946. doi: 10.1603/0022-2585(2006)43[936:HBAHBA]2.0.CO;2. - DOI - PubMed
    1. Ponçon N, Toty C, L'Ambert G, Le Goff G, Brengues C, Schaffner F, Fontenille D. Biology and dynamics of potential malaria vectors in southern France. Malar J. 2007;6:18. doi: 10.1186/1475-2875-6-18. - DOI - PMC - PubMed
    1. Ponçon N, Toty C, L'Ambert G, Le Goff G, Brengues C, Schaffner F, Fontenille D. Population dynamics of pest mosquitoes and potential malaria and West Nile virus vectors in relation to climatic factors and human activities in the Camargue, France. Med Vet Entomol. 2007;21:350–357. - PubMed

MeSH terms