The Potential Distribution ofPhlebotomus papatasi(Diptera: Psychodidae) in Libya Based on Ecological Niche Model

Abstract

The increased cases of cutaneous leishmaniasis vectored by Phlebotomus papatasi (Scopoli) in Libya have driven considerable effort to develop a predictive model for the potential geographical distribution of this disease. We collected adult P. papatasi from 17 sites in Musrata and Yefern regions of Libya using four different attraction traps. Our trap results and literature records describing the distribution of P. papatasi were incorporated into a MaxEnt algorithm prediction model that used 22 environmental variables. The model showed a high performance (AUC = 0.992 and 0.990 for training and test data, respectively). High suitability for P. papatasi was predicted to be largely confined to the coast at altitudes <600 m. Regions south of 300 degrees N latitude were calculated as unsuitable for this species. Jackknife analysis identified precipitation as having the most significant predictive power, while temperature and elevation variables were less influential. The National Leishmaniasis Control Program in Libya may find this information useful in their efforts to control zoonotic cutaneous leishmaniasis. Existing records are strongly biased toward a few geographical regions, and therefore, further sand fly collections are warranted that should include documentation of such factors as soil texture and humidity, land cover, and normalized difference vegetation index (NDVI) data to increase the model's predictive power.

Spatially Correlated Time Series and Ecological Niche Analysis of Cutaneous Leishmaniasis in Afghanistan

“…The seasonality in our data was also confirmed by the significance of trend and sinusoidal wave term as well as precipitation and temperature in our final model. These findings are similar to other studies indicating a positive association between precipitation, temperature and leishmaniasis [39,53].…”

“…Precipitation and temperature provides significant contribution in predicting the suitable condition for leishmaniasis with average precipitation in April contributing the greatest. This is similar to studies that found precipitation to contribute significantly to the predictive probability of the presence of leishmaniasis [19,39] and sandflies [53].…”

“…Previous studies have described the occurrence of the disease as seasonal [36,39,53]. The seasonality in our data was also confirmed by the significance of trend and sinusoidal wave term as well as precipitation and temperature in our final model.…”

“…The seasonality in the occurrence of zoonotic cutaneous leishmaniasis in humans was attributed to seasonal activity of the rodents which are natural reservoir hosts of the disease [11,52]. Regions with good vegetation for plant growth have been described to provide shelter and food for rodents thereby providing ideal sand fly habitats [53].…”

Species diversity of sand flies and ecological niche model of Phlebotomus papatasi in central Iran

“…So, our findings can be used in future ecological studies on the potential of presence for this main vector of zoonotic cutaneous leishmaniasis in Iran and other parts of its' geographical distribution around the world. Study on potential distribution of P. papatasi in Libya using MaxEnt model showed precipitation had the most influence, while temperature and elevation had less weight in the model (Abdel-Dayem et al, 2012). Since this sand fly is peridomestic species and opportunistic feeder but prefers to feed on humans and rodents (Yaghoobi-Ershadiet al,1995), it can easily breed around the human dwellings.…”