Impact of environmental changes and human-related factors on the potential malaria vector, Anopheles labranchiae (Diptera: Culicidae), in Maremma, Central Italy.

The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when a national campaign for malaria elimination drastically reduced the presence of the main vector Anopheles labranchiae Falleroni. However, the introduction of rice cultivation over 30 yr ago has led to an increase in the An. labranchiae population and concern over possible malaria reemergence. We studied the impact of anthropogenic environmental changes on the abundance and distribution of An. labranchiae in Maremma, focusing on rice fields, the main breeding sites. Adults and larvae were collected in three main areas with diverse ecological characteristics. Data were collected on human activity, land use, and seasonal climatic and demographic variations. We also interviewed residents and tourists regarding their knowledge of malaria. Our findings showed that the most important environmental changes have occurred along the coast; An. labranchiae foci are present throughout the area, with massive reproduction strictly related to rice cultivation in coastal areas. Although the abundance of this species has drastically decreased over the past 30 yr, it remains high and, together with climatic conditions and the potential introduction of gametocyte carriers, it may represent a threat for the occurrence of autochthonous malaria cases. Our findings suggest the need for the continuous monitoring of An. labranchiae in the study area. In addition to entomological surveillance, more detailed knowledge of human-induced environmental changes is needed, so as to have a more complete database that can be used for vector-control plans and for properly managing emergencies related to autochthonous introduced cases.

Results preliminary attempts to control the larvae of Leptoconops (Holoconops) kerteszi Kieffer, 1908 (Diptera, Ceratopogonidae) in the coastal wetlands of Tuscany, Italy.

Leptoconops spp. are small midges, members of the family Ceratopogonidae, that are relatively widespread in wetlands with sandy or silty-clay soils, including many tourist sites. Although very few of the species are proven vectors of pathogens, the blood-feeding females attack mammals, including humans, in large swarms and their painful bites may cause severe reactions, especially in children. Although Leptoconops spp. may limit the socio-economic development of an area, there are currently no effective methods for the control of their natural populations, and the repellents and netting used against mosquitoes are ineffective against these midges. The diurnal control of the adults with pesticides may have unacceptable impacts on non-target species, including humans, and be ineffective because the adult females can easily be carried, from untreated areas to treated, on the wind. In the present study, the use of a diflubenzuron-based insecticide against the larvae of Leptoconops (Holoconops) kerteszi Kieffer, 1908 - a sand-reproducing species that is widespread in certain coastal areas of the Italian province of Grosseto - was explored. In Grosseto, in summer, attacks by swarms of adult L. kerteszi create problems for the local people and the many tourists. The encouraging results of preliminary tests are discussed in relation to the potential use of diflubenzuron for the integrated control of L. kerteszi populations.