Artemisia spp. essential oils against the disease-carrying blowfly Calliphora vomitoria

Synanthropic flies play a considerable role in the transmission of pathogenic and non-pathogenic microorganisms. In this work, the essential oil (EO) of two aromatic plants, Artemisia annua and Artemisia dracunculus, were evaluated for their abilities to control the blowfly Calliphora vomitoria. Artemisia annua and A. dracunculus EOs were extracted, analysed and tested in laboratory bioassays. Besides, the physiology of EOs toxicity and the EOs antibacterial and antifungal properties were evaluated.

Both Artemisia EOs deterred C. vomitoria oviposition on fresh beef meat. At 0.05 μl cm^-2 A. dracunculus EO completely inhibited C. vomitoria oviposition. Toxicity tests, by contact, showed LD₅₀ of 0.49 and 0.79 μl EO per fly for A. dracunculus and A. annua, respectively. By fumigation, LC₅₀ values were 49.55 and 88.09 μl l^-1 air for A. dracunculus and A. annua, respectively. EOs AChE inhibition in C. vomitoria (IC₅₀ = 202.6 and 472.4 mg l^-1, respectively, for A. dracunculus and A. annua) indicated that insect neural sites are targeted by the EOs toxicity. Finally, the antibacterial and antifungal activities of the two Artemisia EOs may assist in the reduction of transmission of microbial infections/contaminations.

Results suggest that Artemisia EOs could be of use in the control of C. vomitoria, a common vector of pathogenic microorganisms and agent of human and animal cutaneous myiasis. The prevention of pathogenic and parasitic infections is a priority for human and animal health. The Artemisia EOs could represent an eco-friendly, low-cost alternative to synthetic repellents and insecticides to fight synanthropic disease-carrying blowflies.