Official websites use. Share sensitive information only on official, secure websites. The two main puzzles of this study are the onset and then sudden stopping of severe epidemics in western Provence a highly malaria-endemic region of Mediterranean France without any deliberate counter-measures and in the absence of significant population flux.
Malaria epidemics during the period from to were analysed against temperature and rainfall records and several other potentially relevant factors. Moreover, the epidemics were most likely not driven by other parameters e.
Until , very severe malarial epidemics affected large areas, whereas after this date, they were rarer and generally milder for local people and were due to canal digging activities. In the latter period, decreased rainfall in December, and more extreme and variable temperatures were observed.
It is known that rainfall anomalies and temperature fluctuations may be detrimental to vector and parasite development. This study showed the particular characteristics of malaria in historical Provence. Contrary to the situation in most other Mediterranean areas, Plasmodium falciparum was most likely not involved during the years with epidemics, the mean temperature during the months of July and August, among other factors, did not play a role and the population had no protective mutation.
The main parasite species was Plasmodium vivax , which was responsible for very severe diseases, but contrary to in northern Europe, it is likely that transmission occurred only during the period where outdoor sporogony was possible, and P. Possible key elements in the understanding of the course of malaria epidemics include changes in the virulence of P. In the past, malaria was endemic and constituted a major health issue in marshy areas of France [ 1 - 3 ].
