Utku Perktaş

Dr. Utku Perktaş is a professor of biogeography in the Biology Department at Hacettepe University.

An outbreak caused by the new coronavirus, COVID-19, started in China earlier this year. To date, more than 130.000 cases have been diagnosed worldwide. A total of 123 countries officially reported infections. This outbreak, which first started as an epidemic, was turned into a pandemic by the World Health Organization on March 11, 2020.

What do the words epidemic and pandemic mentioned in our daily conversations in the sensitive days mean for the COVID-19 outbreak? What do the terms epidemic and pandemic mean? Epidemia means the emergence of a particular disease in a large number of people in a particular area at the same time. The first patients caused by COVID-19 originated in Wuhan province of China; this marked the epidemic situation. This situation later spread across China. Pandemic means that a disease occurs in more than one continent or almost all over the world, and it is found in almost all people, animals or plants. Also, a pandemic is a concept that includes passing the disease from person to person, from animal or plant to human or vice versa. For example, malaria in some parts of the world is still pandemic. Similarly, the new-coronavirus-related respiratory disease has also had a pandemic condition worldwide. It reached a dimension that threatens every geography in the world depending on human movements. According to current reports, it even began to reach small islands in the middle of the Pacific Ocean. The mobility of people who are the host of the virus has reached an incredible point with the opportunities provided by the airways.

In a recent article, I mentioned that the reason for the start of the epidemic situation for COVID-19 would be global warming due to climate change. Although there is some evidence of this issue, it is clear that we need more and more evidence. However, there is one thing we should keep in mind that the increasing human population and the global warming problem that is related to this increase will bring other problems in the near future. Let’s care about climate change!

Is climate a vital parameter for COVID-19

New scientific evidence, and scientific publications in recent months endorse that there may be a significant relationship between coronavirus and climate. According to what we have read and experts say, the virus tends to survive in humid environments, droplets for a certain period of time. So, what does this mean? Without much complication, we can say that, as the environment gets dry, the weather gets warmer, the chances of the virus surviving in the external environment will decrease. That’s why experts say we need to ventilate the environments we live in these days. So, when you wake up in the morning, the first job is to open the curtains and windows of your room, expose your apartment to fresh air and sun for a while; do this every day. Do not forget the Turkish proverb “If the sun does not enter the house, the doctor will”!

So, if we think of this humid condition for the whole world and associate it with the average temperatures we see throughout the year, what is the result of understanding the distribution of the virus? So, can we predict what kind of distribution pattern the virus will create in the world depending on the climate in the coming months? As a biogeographer, I can say that this is one of the essential questions to answer. Indeed, Spanish biogeographers must have thought like me that, following a scientific way, they modeled the relationship of the virus to the climate in the light of modern analysis. They also showed in a scientific perspective how the virus will be distributed worldwide in a year. The results are very interesting and guide the future planning against the virus. Let me summarize briefly…

Miguel B. Araújo is recognized as one of the leading names in the effects of climate change on biodiversity. Prof. Araújo and his research team, which are linked to research institutes in Spain, Portugal, and Denmark, introduced a comprehensive model of the coronavirus. With this model, they showed the ecological niche of the virus, that is, the locations of the virus in the world, depending on the climatic preference. The results projected the ecological niche of the virus, taking into account the seasonal changes in temperature and precipitation throughout the year. What the projection results obtained at 3-month intervals can be seen in the figure given in the text. The figure contains distributions with colors ranging from blue to red, and geographies where colors shift from blue to red are indicated as places where the virus is most likely to be found. In other words, these geographies on the map are the places where climate suitability is best for the virus.

Maps below show the ecological niche of the virus around the year.

CLIMATE SUITABILITY IN JANUARY
CLIMATE SUITABILITY IN APRIL
CLIMATE SUITABILITY IN JUNE
CLIMATE SUITABILITY IN OCTOBER

Which countries are more risky in summer?

As can be seen from the figure, the risk of spread for coronavirus is related to seasonal changes in climate suitability. The most important conclusion from these results is that the risk is not between the northern and southern hemispheres of the world, but between the temperate and cold temperate regions of the world. In other words, in hot-temperate countries such as (large regions of) China, Central Asian countries and Iran in Asia, Italy, Spain, Portugal, France, England, Germany, Greece and Turkey in Europe and the U.S.A in North America, the virus is more active in seasons such as autumn, winter, and spring. While in cold-temperate countries such as Scandinavian countries, Canada and (large regions of) Russia, the virus season is more Visible until the end of the summer, the potential risk peaks in the summer. At this point, it is discussed that the pandemic situation will be global, but it will not affect every place at the same intensity at the same time. Another point that should not be skipped is the evaluation of the arid regions as regions with low risk compared to the temperate zone.

This study interprets the distribution of the virus by adhering to the climate. However, although the climate is an important variable, it is of course not enough to explain everything about the distribution of the virus. The virus needs a host to move. This host, which is the most important reason for the pandemic situation, is human. The mobility and behavior of man is essentially the most important factor that will affect the density of the host. When I started writing, I mentioned that the virus started to be seen even in the farthest corners of the world. Therefore, the steps taken to limit human movements will undoubtedly prevent the spread of the outbreak. Then, depending on the climate, the virus will gradually disappear.

The result continues to remain isolated for some time patiently, without panic, respecting scientific results…