Probable autochthonous introduced malaria cases in Italy in 2009-2011 and the risk of local vector-borne transmission

We describe two cases of probable autochthonous introduced Plasmodium vivax malaria that occurred in 2009 and 2011 in two sites of South-Central Italy. Although the sources of the infections were not detected, local transmission could not be disproved and therefore the cases were classified as autochthonous. Sporadic P. vivax cases transmitted by indigenous vectors may be considered possible in some areas of the country where vector abundance and environmental conditions are favourable to malaria transmission. Two probable autochthonous introduced cases of Plasmodium vivax malaria were notified from two sites in South-Central Italy in 2009 and 2011. We report on the possible risk of local vector-borne malaria transmission in areas in Italy where the vector abundance and environmental conditions are favourable to malaria transmission. Although soon after the World War II malaria was eliminated from Mediterranean countries, the rise in the average temperature of the earth [1], environmental modifications, the increase of international travel, and socio-economic constraints recorded in the last decades [2], have raised the concern about the possible re-emergence of malaria in some of these countries, such as Italy, where malaria had been endemic before [3]. However, the presence of competent vectors and of reservoirs of the parasites, i.e. humans carrying gametocytes in their blood may play a major role in malaria re-emergence. The recent outbreaks of malaria in Greece, although limited in size, are paradigmatic of this possible public health threat [4]. In Italy, since the five-year eradication campaign in 1947-1951, one single confirmed case of autochthonous introduced P. vivax malaria (transmitted by an indigenous vector) [5], has been recorded in Grosseto, Tuscany Region in 1997 [6]. Hereby, we report two probable but not proved autochthonous introduced [5] malaria cases that occurred in Italy in the last three years, namely between 2009 and 2011.