Pauline Zulueta, Cumming School of Medicine
March 9, 2018
High-containment lab raises sand flies to investigate global health issue
They鈥檙e smaller than a mosquito; they only live for about a month, yet these tiny flying insects are having a big impact on people鈥檚 health. During their short life, sand flies infect about one million people each year with the parasite听Leishmania,听causing a chronic disease called Leishmaniasis. The World Health Organization estimates as many as 30,000 people die annually from the disease, and hundreds of thousands of others have lifelong disfiguring scars on their skin. There is no vaccine. Treatment with intravenous medications can be extremely painful and hard to access.
In a highly specialized lab at the听草莓污视频导航鈥檚听听(CSM) a team of researchers is raising sand flies to understand more about transmission of the disease and our immune system鈥檚 response to it. Within the lab, the scientists created a real-life scenario; flies become naturally infected with听Leishmania听parasites, and then with a bite the female flies give the disease to a mouse. 听
鈥淲e used to think that initiating infections with these pathogens with a needle was a sufficient way to study disease in the mammalian host, but we now know that isn鈥檛 enough. There鈥檚 a huge difference in the natural progression of this disease when you compare the transmission between a fly bite and a needle,鈥 says Nathan Peters, PhD, an associate professor cross-appointed in the CSM and the Faculty of Veterinary Medicine and member of the听. 鈥淯ntil we fully understand the development of this disease in its many forms, we won鈥檛 be able to develop an effective vaccine.鈥
There are three forms of the disease. The most common results in lesions and ulcers on the skin and can lead to serious disability. Another form attacks the mucous membranes of the nose, mouth and throat, and the most serious form shows up in the spleen and liver and is fatal in 95 per cent of cases, if left untreated.
Leishmaniasis is considered a tropical disease, and is commonly found in South America, Africa the Middle East and India, but due to climate change, incidents of the disease are starting to show up in new areas including the island of Sicily, the south of France and Spain.
Dr. Bonnie Meatherall, an infectious disease specialist and assistant professor in the听听at the CSM, treats a handful of patients each year, mostly travellers. 鈥淢any of the patients I see didn鈥檛 expect to contract this disease on their vacation. They often are on an excursion, like a common jungle adventure as part of their trip.鈥 Meatherall suggests vacationers consider pre-travel counselling to educate themselves on the health risks even at popular destinations.听
While a lot of field research is conducted at the locations where the disease is commonly spread, it can be difficult for scientists to follow the full cycle of the disease, to include how the fly became infected, through to where it contacted a human host. That鈥檚 where the Peters lab comes in. The temperature and humidity levels in the lab and constant care of a sand fly colony allows researchers to map each stage of a fly鈥檚 life and the complete development of the disease in a host.听
The insectary, built with support from the Canadian Foundation for Innovation (CFI) and Alberta Economic Development and Trade, is state of the art and includes key card access, progressive negative pressure, and self-closing mechanically interlocking doors to ensure the safety of researchers and the preservation of the sand fly colony, which needs highly specialized care to thrive.
Peters says this research could have far-reaching implications in our understanding of other diseases transmitted by insects, including the malaria parasite,听Plasmodium, Zika and West Nile viruses, and Lyme disease bacteria.
Peters credits 草莓污视频导航 for having a 鈥榗an-do鈥 attitude when he first proposed building the facility during his recruitment. 鈥淚 have to say, the leadership at the Snyder Institute saw the uniqueness and potential of such a facility and were all extremely supportive,鈥 he says.
Nathan Peters, PhD, is an associate professor in the departments of听听at the CSM, and in the听Department of Comparative Biology and Experimental Medicine听at the听听.