Faunistic study of sandflies in Greece.

A faunistic study of phlebotomine sandflies was carried out on the mainland and on four islands in Greece between 1999 and 2004. Sandflies were collected in 18 areas, and the population structure was observed and recorded. A total of 10 species were identified; their distribution is presented here. Of these, the species Phlebotomus neglectus Tonnoir and P. perfiliewi Parrot (Diptera: Psychodidae), epidemiologically the most important vectors of leishmaniases and sandfly fever in Greece, were shown to be present in the main endemic foci of the country.

Ticks, tick-borne rickettsiae, and Coxiella burnetii in the Greek Island of Cephalonia.

Domestic animals are the hosts of several tick species and the reservoirs of some tick-borne pathogens; hence, they play an important role in the circulation of these arthropods and their pathogens in nature. They may act as vectors, but, also, as reservoirs of spotted fever group (SFG) rickettsiae, which are the causative agents of SFG rickettsioses. Q fever is a worldwide zoonosis caused by Coxiella burnetii (C. burnetii), which can be isolated from ticks. A total of 1,848 ticks (954 female, 853 male, and 41 nymph) were collected from dogs, goats, sheep, cattle, and horses in 32 different localities of the Greek island of Cephalonia. Rhipicephalus (Rh.) bursa, Rh. turanicus, Rh. sanguineus, Dermacentor marginatus (D. marginatus), Ixodes gibbosus (I. gibbosus), Haemaphysalis (Ha.) punctata, Ha. sulcata, Hyalomma (Hy.) anatolicum excavatum and Hy. marginatum marginatum were the species identified. C. burnetii and four different SFG rickettsiae, including Rickettsia (R.) conorii, R. massiliae, R. rhipicephali, and R. aeschlimannii were detected using molecular methods. Double infection with R. massiliae and C. burnetii was found in one of the positive ticks.

Colonization of Phlebotomus neglectus (Diptera: Psychodidae), the major vector of visceral leishmaniasis in Greece.

Colonization of Phlebotomus neglectus Tonnoir, the major vector of visceral leishmaniasis, in Greece is reported for the first time. Starting with wild-caught specimens, a small closed colony was established that was maintained for 17 mo or 10 generations. Gonotrophic discordance, stenogamic mating behavior, low fecundity, and dormancy because of low temperature were the most important findings that characterized the colony.

Typing of sandflies from Greece and Cyprus by DNA polymorphism of 18S rRNA gene.

A simple and reliable technique was developed to distinguish Phlebotomine sandflies by restriction fragment length polymorphism of PCR-amplified (PCR-RFLP) 18S rDNAs. Seven morphologically identified sandflies species from several localities of Greece and Cyprus were studied, and specific patterns were developed by double digesting amplified 18S rDNAs with HpaII and RsaI. Three additional species of the subgenus Larroussius were distinguished by a second double digestion with AccI and BanI. We have successfully applied the method on samples in which morphological characters were badly distinguished due to poor storage conditions and in larval stages.

Water wells as a habitat of sand fly (Diptera: Psychodidae) vectors of visceral leishmaniasis in Greece.

Overall, 37 of 79 water wells in 3 diverse geographic areas of Greece were found to harbor sand flies. The predominant species were Phlebotomus tobbi Adler, Theodor & Lourie and P. neglectus Tonnoir, species implicated in the transmission of Leishmania infantum Nicolle. Three additional species of Phlebotomus and 2 Sergentomyia spp. also encountered. Wells appear to be resting and possibly breeding habitat for sand flies in Greece.

Transmission cycle of murine typhus in Greece.

A field study, based on a follow up of the 49 human cases of the disease that occurred on the island of Evia in 1985, has established the transmission cycle of murine typhus in Greece for the first time. In 1993, two types of traps were used to catch 53 rats, all of them Rattus norvegicus, in the localities where the cases had occurred. Some 300 fleas, all of them probably Xenopsylla cheopis, and a few ticks and mites were collected from the rats. Eight of the fleas were found positive for Rickettsia typhi by PCR and anti-R. typhi antibodies were found in the sera of 48 (91%) of the rats at titres between 1:8 and 1:524,288 and in 22 (42%) at titres > 1:256. The commensal rat population in the general area of study was both ubiquitous and abundant. Murine typhus is obviously endemic in the area and probably of much greater public health significance than the number of reported cases indicates.

Leishmaniasis in greater Athens, Greece. Entomological studies.

Greater Athens, the largest urban area in Greece, has a population of 3.1 million and is home for most of the human and canine cases of visceral leishmaniasis (VL) reported in Greece. Seven species of sandflies (Diptera: Psychodidae) were identified in light- and sticky-trap surveys in the area in 1993. Although none of the flies was found in wooded areas or scrub, flies were collected from quarries, corrals, wells, walls, houses and animal shelters. There were small 'island' populations in residential districts and moderate or large populations in the quarries and corrals in the foothills of the mountains bordering the area and in the hills near the city centre. Phlebotomus neglectus, the putative vector of VL in the area, was ubiquitous; it predominated in the quarries and was common in the sampled corrals and residential habitats. The distribution, abundance and seasonal activity of all seven species of sandflies are described and discussed.

Comparative susceptibility of mosquito species and strains to oral and parenteral infection with dengue and Japanese encephalitis viruses.

Thirty-four strains of Asian and Pacific mosquitoes belonging to 22 species of 7 genera were compared for oral and/or parenteral susceptibility to infection with 1 or more strains of each of the 4 dengue serotypes. Surprisingly, several species of common man-biting Aedes were much more susceptible to oral infection with each of the 4 dengue serotypes than was Aedes aegypti. These species included Aedes albopictus and members of the scutellaris group of the subgenus Stegomyia found on South Pacific islands. Mosquito strains and species relatively susceptible to 1 dengue serotype usually were relatively susceptible to the others also. Almost all species of Aedes tested were uniformly susceptible to parenteral infection with the dengue viruses but, with the exception of a species of Tripteroides, species of all other genera were comparatively resistant to that mode of infection. Dengue viruses usually replicated to about the same extent in orally-infected mosquitoes as they did in parenterally-infected specimens of the same species. Seventeen species of mosquitoes of 7 genera also were tested for parenteral susceptibility to infection with Japanese encephalitis virus. With the possible exception of 2 species of Anopheles, the virus replicated to about the same degree in all species tested and achieved levels considerably higher than did any of the dengue viruses in the same mosquito strain and species held under the same conditions.

Evaluation of personal protection methods against phlebotomine sand flies including vectors of leishmaniasis in Panama.

Three personal protection methods were evaluated against phlebotomine sand flies in Panama. Skin applications of five selected repellents including deet (N,N-diethyl-m-toluamide) provided a mean coefficient of protection (CP) of 99.2% against the attack of at least three sand fly species. Deet-treated net jackets also provided good protection, but it was concluded that an additional application of repellent to the unprotected face was necessary for maximum protection. Permethrin-treated clothing did not provide the protection expected. Apparently sand fly behavior and resistance to quick knock-down were responsible for the numbers of bites recorded, and therefore maximum protection from bites would require application of deet or another suitable repellent to the exposed skin when wearing permethrin-treated clothing.