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Seasonal and Circadian Dynamics

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Old World

Circadian activity

Italy, Emilia Romagna: In studies, Ph. perfiliewi had its maximum biting activity around 3:00 hours in the morning (Killick-Kendrick et al., 1977).

Iran: A not exclusively nocturnal behaviour in Ph. papatasi was observed, with sand flies still quite active in darkened rooms or shaded animal shelters between 6:30 and 10:00 hours (Javadian et al., 1977).

Oman: The circadian activity of Arabian sand flies, mainly Ph. alexandri and Sergentomyia clydei, increased rapidly after sunset (18:50 hours) and was fairly constant on a high level during 9 hours of darkness until dawn, when it decreased rapidly. Few flies were still active at 7:00 hours, 1.5 hours after sunrise. The main factor affecting sandfly activity was light intensity, followed by low relative humidity, followed by low wind velocity. Optimum humidity was around 10%, probable maximum wind velocity was 3.5 m/sec and 11°C was the probable minimum temperature. Best nights for catches had a low humidity (10-25%) and low wind speed (< 0.3 m/sec) in combination with highest temperatures (31-43°C) (Roberts, 1994).

Seasonal activity

Exemplary, the data of the following regions is listed:

Spain, northeast (Aragon): One of the prevalent sandfly species, Sergentomyia minuta, which is also prevalent in diverse other localities of the Mediterranean Area (see Benito-De Martin et al., 1991), reached its highest density in the coldest and most humid areas of the Northeast of Spain. Seasonal activity in the was depending on the degree of urbanization with the longest span (6 months) in suburban areas, decreasing towards periurban and rural foci. The species showed one (July-August) as well as two (June, August-September) peaks of density depending on the area and vegetation (Benito-De Martin et al., 1991).

Spain, south: The longest seasonal activity period recorded in this area has been nine months (Martinez-Ortega, 1984; Morillas-Marquez et al., 1983; Sanchis-Marin et al., 1986).

Jordan, southern Jordan Valley: The most abundant sandfly, Ph. papatasi, which distribution and temporal association points to significance in the transmission of Leishmania, had its peak abundance in September and October, then declining sharply by late November (Janini et al. 1995).

Kenya: Sandfly population was highest during the rainy seasons, April-June and November-December. A significant association was observed between monthly sandfly abundance and rainfall in the previous month (Robert et al., 1994).

Senegal: The three most abundant species of the study, S. dubia, S. schwetzi, S. buxtoni, had their population peak in February (Ba et al., 1998).

India: Ph. papatasi showed its maximum indoor resting density during the monsoon season. A positive correlation between density and rainfall could be observed. The finite rate of natural increase of the field population was maximum in October and minimum in April (Srinivasan et al. 1993), similar to findings on the African continent.

   

References

  • Ba, Y., J. Trouillet, J. Thonnon and D. Fontenille: Phlébotomes du Sénégal (Diptera <FONT size=2>– </FONT>Psychodidae): peuplement et dynamique des populations de la region de Mont-Rolland. Parasite 5, 143-150, 1998
  • Benito-De Martin, M.I., J. Lucientes-Curdi, J. Orcajo-Teresa and J.A. Castillo-Hernandez: Seasonal dynamics of Sergentomyia minuta (Rondani, 1843) populations in Aragon (N. E. Spain). Parassitologia 33 (Suppl.) 89-97, 1991
  • Janini, R., E. Saliba and S. Kamhawi: Species composition of sand flies and population dynamics of Phlebotomus papatasi (Diptera: Psychodidae) in the southern Jordan Valley, an endemic focus of cutaneous leishmaniasis. J. Med. Entomol. 32, 822-826, 1995
  • Javadian, E., R. Tesh, S. Saidi and A. Nadim: Studies on the epidemiology of sandfly fever in Iran III. Host-feeding patterns of Phlebotomus papatasi in an endemic area of the disease. Am. J. Trop. Med. Hyg. 26, 294-298, 1977
  • Killick-Kendrick, R., P.D. Ready and S. Pampiglione: Notes on the prevalence and host preferences of Phlebotomus perfiliewi in Emilia-Romagna, Italy. In: Rioux, J.-A. (ed.): Ecologie des Leishmanioses. Coll. Internat. CNRS No. 239, Montpellier, France, 1974, pp 169-175, 1977
  • Martinez-Ortega, E.: Fenología de Sergentomyia minuta (Rondani, 1843) (Diptera, Psychodidae, Phlebotominae) en el sureste de la Peninsula Ibérica. Bol. Asoc. Esp. Entomol. 8, 35-39, 1984
  • Morillas-Marquez, F., D.C. Guevara-Benitez, J. M. Ubeda-Ontiveros and J. Gonzalez-Castro: Fluctuations annuelles des populations de Phlébotomes (Diptera, Phlebotomidae) dans la province de Grenade (Espagne). Ann. Parasitol. Hum. Comp. 58, 625-632, 1983
  • Robert, L.L., K.U. Schaefer, and R.N. Johnson: Phlebotomine sandflies associated with households of human visceral leishmaniasis cases in Baringo District, Kenya. 88, 649-657, 1994
  • Roberts, D.M.: Arabian sandflies (Diptera: Psychodidae) prefer the hottest nights? Med. Vet. Entomol. 8, 194-198, 1994
  • Sanchis-Marin, M., F. Morillas-Marquez, J. Gonzalez-Castro, I. Benavides-Delgado and A. Reyes-Magaña: Dinámica estacional de los flebotomos (Diptera, Phlebotomidae) de la provincia de Almeria (España). Rev. Iber. Parasitol. 46, 285-291, 1986
  • Srinivasan, R., K.N. Panicker and V. Dhanda: Population dynamics of Phlebotomus papatasi (Diptera: Phlebotomidae) in Pondicherry, India. Acta Trop. 54, 125-130, 1993

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