A team of scientists have identified a species of bloodsucking flies that also have a taste for cannabis. The researchers, led by professor Alon Warburg from the Hebrew University of Jerusalem, published their findings this week in the journal Proceedings of the National Academy of Sciences.
The scientists were studying sand flies, which can transmit diseases including leishmaniasis, a serious and disfiguring disease caused by a parasite in the blood. The authors of the report wrote that sand flies pick up and pass along the parasite that causes the disease while sucking the blood of larger animals to nourish their next brood of young.
“Sand fly females become infected with Leishmania parasites and transmit them while imbibing vertebrates’ blood, required as a source of protein for maturation of eggs,” they wrote.
The sand flies also suck the sap of plants and by studying which plants the insects are eating, the scientists can learn more about the spread of the parasites.
“In addition, both sand fly sexes consume plant-derived sugar meals. Therefore, the structure of plant communities can influence the transmission dynamics of sand fly-borne diseases,” the researchers explained.
To learn more about the sand flies diet, the scientists trapped samples in five locations from Brasil to the Middle East, where a serious outbreak of leishmaniasis fueled by civil unrest in Syria is affecting thousands. The scientists then analyzed the DNA found inside the sand flies to determine from which plants they had been feeding.
Sand Flies Prefer Cannabis
The researchers learned that many of the sand flies had been sucking the sap of cannabis, even though wild samples of the plant were found in only one collection site. In fact, so many of the sand flies had been consuming cannabis sap that the team of scientists believes they prefer it over other plants.
“We infer this preference based on the substantial percentage of sand flies that had fed on C. sativa plants despite the apparent “absence” of these plants from most of the field sites,” they wrote.
The researchers determined that the low availability of cannabis coupled with its high prevalence in the samples indicated the sand flies were seeking out the plant as a food source.
“We conclude that cannabis comprised but a small fraction of the available sugar sources in any particular habitat and that its ample representation among sand fly plant meals signifies bona fide attraction,” the scientists wrote.
The scientists went on to note that the sand flies’ attraction to cannabis could have implications for the prevention of leishmaniasis and other serious diseases.
“Our findings demonstrate that, in proportion to their abundance, Cannabis sativa plants were consumed by sand flies much more frequently than expected (i.e., C. sativa is probably highly attractive to sand flies). We discuss the conceivable influence of C. sativa on the transmission of Leishmania and its potential utility for sand fly control.”
The researchers explained that insect traps specifically attractive to sand flies could be produced by including an extract of cannabis plants as bait. Such species-specific traps could potentially be an effective control against sand flies and thus slow the spread of disease-causing parasites.