Relative performance of surveys for the Old World screwworm fly, Chrysomya bezziana, in Iraq based on fly trapping and myiasis monitoring

Abstract

Fly traps are being used to monitor populations of Old World screwworm (OWS) flies in Iraq. We evaluated trapping systems for seasonality and trap type and compared the results with monitoring of OWS flies using myiases on animals. Fly catches increased during spring and autumn with low catches during the hot, dry summer and the cold winter. The effectiveness of the sticky trap/Swormlure and LuciTrap/Bezzilure for OWS flies could not be determined because no OWS were caught during the comparison period in 2009. The LuciTrap caught more flies of all other species than the sticky trap during this comparison. The numbers of myiases detected on animals in Iraqi provinces from 1996 to 2013 are provided. The high numbers of myiases in most provinces in the late 1990s were followed by lower numbers and subsequent apparent elimination in about half of the provinces. Myiases were detected mainly in sheep (77.0%) and goats (16.7%). A temporal comparison of OWS fly detection with traps and animal myiases in Babil province demonstrated a similar sensitivity and a weak correlation between the two methods. We recommend that both fly trapping and inspection of animals for myiases are used for the detection or monitoring OWS fly populations and that Iraq and the international organisations initiate an area-wide integrated OWS fly program, including the sterile insect technique, with the aim of eradicating the OWS fly from Iraq.