As Ukrainian scientist in the United States helped to prove the importance of masks during a pandemic

Physicist Valentin Stadnitskii was one of the researchers, proved mask can significantly slow the spread of SARS-CoV-2. DW talked to him about his work in the United States.

Как украинский ученый в США помог доказать важность масок во время пандемии

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Optional sneeze or cough to spread droplets in the air that can carry the coronavirus SARS-CoV-2 — just normal conversation. This conclusion was confirmed in the United States during the experiment with laser carried out by group of scientists of the National Institute of health. One of the scientists in this team is a Ukrainian physicist Valentin Stadnitskii.

Meanwhile, the scientists found that the drops are stored in air for up to eight minutes. The results of the study drew worldwide media attention, becoming yet another argument in the dispute about the importance of using protective masks during an outbreak COVID-19. In an interview with DW Stadnitskii told about the progress of this experiment and their experience in the United States.

DW: the Study team in which you worked, can give a clue to the rapid spread of the coronavirus. How did you manage to get those results?

Valentin Stadnitskii: it All started with the idea of Dr. Adrian Bax, who sought to visualize the drops of saliva, exhaled by the person during speaking and too small for someone to see them with the naked eye. He and Dr. Philip Anfinrud — his colleague at the laboratory of chemical physics (LCP) at the National Institute of diabetes and digestive diseases and kidney, where I also work as a researcher was thinking about using lasers for the visualization of the drops. The Friday night doctor Anfinrud painted the inner walls of cardboard boxes, cut holes in it and the next morning began to adjust the optics in their laser lab. He took me to the team because I have extensive experience with lasers. And before the end of the morning we had designed and ready to work the camera. The three of us spent the rest of the weekend, recording video and interpreting the received material.

Confirm your findings by other studies of American or international institutions?

At the time of our work we were not aware of any published studies that use laser technology to visually demonstrate a drop of saliva into the air during speaking, although a group of scientists in Japan has published something similar in relation to sneezing. Of course, data on the distribution of these drops have been published before — for example, in one work 2019, which showed that speaking leads to the release of more drops than breathing and loud speaking increases the spread of these droplets.

What kind of mask you wear personally?

Our report demonstrated that a simple speaking, even without the sneezing and coughing contributes to the spread of thousands of potentially dangerous drops in the air, and the use of simple masks, not even the N95, a significant way prevents it spread. I personally follow the recommendations of the Centers for control and prevention of diseases of the USA about which mask to wear.

In General, you are afraid of being infected with coronavirus?

It is natural to man to fear the unknown. But fear does not solve problems, only affects our judgments and ability to move forward. But we can study the problem and understand the associated risks. It is my duty as a scholar to aggressively explore something unknown. I use my experience and knowledge gained over the years to do an analysis of the possible risks and benefits. The risk of infection is, but I understand the importance of using PPE and the power of social distancing. With this knowledge I can reduce risk and focus on solving other problems — such as those outlined in the study.

Before moving to the USA in 2011, you studied at the Kiev national University of Taras Shevchenko. What was your path to scientific work in America?

My mother was a chemist and wrote his dissertation at the Kiev national University, and his father an engineer. But the desire of my parents were crossed out by the collapse of the Soviet Union — mother had to abandon her passion and become an accountant to feed his family. She always joked that her thesis, I was, and encouraged my brother and me to realize our ambitions. For her, education was our priority. I was fond of mathematics and natural Sciences, so left school with advanced study of languages and continued her studies at the Kiev Natural-scientific Lyceum No. 145.

I received a bachelor’s and master’s degree in physics national University of Kyiv with honors. But during the last two years of study at University, I started to think about their next career steps and found it logical to continue studies on a doctoral programme. I considered the possibilities of such programmes in the UK, Germany, Belgium and the United States. It was difficult — I had to write many drafts for a truly compelling cover letters and to pass the exam in English to convince the universities that I’m a worthy candidate.

Hard work has paid off and I received several invitations for interviews from Europe, and several invitations to doctoral programs in the United States. Thus I found myself at Purdue University in Indiana.

Than working in the U.S. different from working in Ukraine, and what would you change in Ukrainian science?

My scientific work in the United States has taught me not to think of the patterns — this helped a team of scientists from different countries and scientific disciplines. When I was a student in Ukraine, I always thought that you must solve every problem, to be able to do good research. But now I understand that outstanding scientific achievements often require involvement of experts from different areas in the team working together. My doctoral studies and research at the National Institute of health would not have been possible without the cooperation and interaction with scientists from other fields of science.

In Ukraine, the impact of years of underfunding. But we can offer the world a very smart, talented and hardworking people who have a serious scientific basis. So I think that cooperation with international scientific communities and universities is the best way for the scientific community in Ukraine. This will give the Ukrainian scientists access to the latest equipment and resources to test their great ideas as members of international teams working on large-scale scientific mysteries, advanced technologies that can improve the quality of human life.

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