Since the practice of announcing the weekly number of cases for each province started last month, the Black Sea region in the north dominates the list of places with highest incidence of COVID-19. The reasons vary, but a group of researchers suspects it might have something to do with a variant exclusive to the region.

Professor Faruk Aydın, head of the Department of Medical Microbiology at Karadeniz Technical University (KTÜ) in the northern province of Trabzon, which had the highest number of weekly cases when the first results were announced, leads the team of researchers. Researchers will analyze samples of the virus collected from Ordu, Trabzon, Samsun, Giresun and Rize, which remain in the "red" category in a map showing the provinces under outbreak risk. "Red" means very high risk, which, in turn, delays "normalization" for the region, while most of the country began the new week with the lifting of a string of restrictions.

Although authorities stepped up inspections against violations of rules in place to curb the pandemic, like mandatory masks and social distancing, it did little to change the risk level. The only apparent change is that Ordu is now ahead of Trabzon with the highest number of weekly cases, around 301 per every 100,000 people.

Researchers will look into COVID-19 samples taken from different families in the region and check their genetic sequence. The study ultimately aims to uncover whether a brand-new mutated virus, differing from foreign variants, exists in the region.

"There must be something else behind the fact that the number of cases here is at least four times higher than other regions," Aydın told Demirören News Agency (DHA) on Thursday. "It can be connected to a U.K. variant, but I don’t think it would affect this region only. Certainly, there may not be any exclusive variant for the Black Sea region, but we have to find out what causes such a high rate of cases here. A variant might be one of the reasons," he said. Experts also link the prevalence of cases to higher mobility in the region where people in close-knit communities tend to visit each other more despite restrictions. Trips to the villages by urban dwellers are also blamed for the increase in the number of cases in rural areas. Likewise, local governorates have escalated inspections targeting people ignoring social distancing recently.

"It will be a cross-sectional study and if we come across a variant, it will shed light on this (mystery behind the prevalence of cases). But it is also possible that there is no variant at all. I can’t comment for now," he added.

Aydın said they would "isolate" eight virus samples from each province and analyze their differences to the U.K., South Africa, Brazil and U.S. variants. Turkey did not report any risky variant exclusive to the country, though some experts claim otherwise.

Dr. Esra Özkaya, one of the researchers, said the suspicion of a variant has always been there due to the outstanding difference between regions. "Our study will have a limited scope, but there should be a wider study to determine the exact variants existing here," she said.

Health Minister Fahrettin Koca said Wednesday it was possible that virus variants were observed more commonly, and they would take measures against them. Koca’s remarks followed the announcement of the daily coronavirus tally, which showed a concerning surge in daily cases, up to more than 11,000 people.

Koca also remarked that the Health Ministry would report the frequency of virus cases for every province weekly and update a province-based risk map every 15 days. "These reports will come out on the weekends and measures, if and when necessary, will be effective from Monday onward for 15 days," he added.

On Monday, Turkey started easing weekend curfews while continuing weeknight curfews to stem the virus's spread. The country also allowed more in-person education and restaurant dining, based on local risk assessment.