Boğaziçi University Launches Research Against Asian Spotted Wing Fly

Southeast Asia-native species notwithstanding, the Asian tiger mosquito is found in different regions of the world and can bite through clothing. The Asian tiger mosquito can carry numerous diseases such as yellow fever, zika, and West Nile virus infection. In recent years, as this mosquito has begun appearing in Turkey, Assistant Professor Dr. Necla Birgül İyison and her team from Boğaziçi University's Department of Molecular Biology and Genetics have started work on developing a biopesticide against it. The goal of this project is to produce a long-term and environmentally friendly solution against the variety of Asian tiger mosquito seen in Turkey, which exhibits different characteristics in each region. Unlike known mosquitoes, the Asian tiger mosquito, which can be active both day and night and can bite through clothing, is seen most frequently in the Black Sea and Marmara regions of Turkey. The project titled "Investigation of Insecticidal Action Mechanisms of Cry Toxins Against Asian Tiger Mosquitoes," in which Boğaziçi University Department of Molecular Biology and Genetics doctoral student Gökhan Gün participates, is also supported by the Scientific Research Fund.

Assistant Professor Dr. Necla Birgül İyison explained the characteristics of the Asian tiger mosquito and the biopesticide development work they aim to achieve in the project to Boğaziçi University's Corporate Communications Office as follows.

The Asian tiger mosquito (Aedes albopictus), a species native to Southeast Asia, in its natural habitat actually only bites animals. However, in recent years, as their distribution areas have expanded, they also bite humans. Additionally, they can lay eggs in artificial environments, which accelerates their spread. Unlike the mosquitoes we know, they can take blood meals at any time of day.

Can bite through clothing

In some people it causes excessive allergic reactions and complaints such as extreme itching and edema at the bite site. Mosquito species living in our country generally circle around before biting and attack when they find a suitable area to feed on blood, whereas the Asian tiger mosquito is extremely aggressive and directly attacks its target, and can bite through clothing. A black mosquito easily distinguished by its appearance. A white line runs down toward the body and white stripes are present on the legs. It is a serious problem as an effective vector in transmitting yellow fever, dengue, zika, chikungunya, West Nile encephalitis, Ross River and similar diseases.

Observed in Marmara Region

According to May 2020 data from the European Centre for Disease Prevention and Control, the Asian tiger mosquito is now considered an established species in the Eastern Black Sea and is reported to have entered the Marmara region. Among the reasons for this spread we can point to excessive human population movement, transport of commercial goods, and climate change. The Black Sea region, particularly due to the abundance of stagnant water accumulations, creates a suitable habitat for the species. We do not yet have a current distribution map for Turkey, but we see complaints coming from the southern regions of Turkey as well.

Work continues for long-term solution

Currently, mosquitoes are mostly controlled through chemical pesticides, but these chemicals both cause environmental pollution and are harmful to human health because they can accumulate in the food chain. Biological pesticides, which are environmentally friendly, have less effect on non-target organisms. This makes it more difficult for the target species to develop resistance and provides a longer-lasting solution compared to chemical pesticides.

Development of toxin specific to Turkey's species is targeted

In the first phase of the project we are working on, we will examine the effects of toxic proteins we are studying on Asian tiger mosquito larvae seen in our country and try to determine lethal dose ratios. This species, which shows distribution worldwide, can exhibit different responses to biological toxins in different regions, so our primary objective is to interact the species seen in Turkey with the toxin so we can compare differences in the DNA sequences of mosquito receptors. Thus we will be able to identify amino acids that play critical roles in receptor-toxin interaction. In the later stages of the project we will work on developing more effective toxin forms, applying them under different environmental conditions, and obtaining forms with easier storage conditions.