The delta coronavirus variant, formerly known as B.1.617, which was first discovered in India, has been rapidly spreading throughout the world—and some doctors are reporting atypical Covid-19 symptoms linked to the variant, including hearing problems and blood clots leading to gangrene.

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Atypical Covid-19 symptoms related to the variant

In India, doctors have reported atypical Covid-19 symptoms in patients infected with the delta variant. According to Ganesh Manudhane, a cardiologist at Seven Hills Hospital in Mumbai, some patients have developed micro thrombi, or small blood clots, that can be severe enough to lead to tissue death and gangrene.

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"I saw three to four cases the whole of last year, and now it's one patient a week," Manudhane said.

Manudhane added that he's surprised to see blood clots in patients across all age groups who have no previous history of coagulation problems. "We suspect it could be because of the new virus variant," he said, adding that he's collecting data to study why some patients are developing the clots and others aren't.

Doctors have also reported some patients developing blood clots in their intestines, which can lead to stomach pain.

Others have reported hearing loss, swelling around the neck, and severe tonsilitis, according to Hetal Marfatia, an ear nose and throat surgeon at King Edward Memorial Hospital in Mumbai. "Every person is showing different symptoms" in the recent surge, she said.

The delta variant spreads worldwide

The delta variant, which has been the driving force behind India's Covid-19 surge, has now spread to more than 60 countries, including the United States and the United Kingdom.

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In the United Kingdom, Covid-19 cases are on the rise again, doubling over the past month from around 2,000 a day to 4,000 a day, the New York Times reports. Research has suggested the delta variant is likely more contagious than the original coronavirus and more likely to infect the partially vaccinated, the Times reports.

British Health Secretary Matt Hancock on Monday said the British government also believes the delta variant is 40% more transmissible than the alpha variant, also known as B.1.1.7, which was first discovered in the United Kingdom.

Meanwhile, a pre-print study by Public Health England released last month found that a single dose of either the Pfizer/BioNTech or AstraZeneca Covid-19 vaccines was just 33% effective against the delta variant, compared to 50% effective against the alpha variant.

Hancock said the government is evaluating data to determine whether the country will still fully reopen on June 21 as previously announced. For now, Hancock said the key is for everyone to get vaccinated.

"The jabs are working," he said, citing British data showing that only three people who had completed their vaccine course were later hospitalized with the delta variant.

"We have to keep coming forward to get them, and that includes vitally that second jab, which we know gives better protection against the delta variant," Hancock added (Leonhardt, New York Times, 6/7; Taylor, Washington Post, 6/7; Shrivastava, Bloomberg, 6/7).