A woman is seen on oxygen support moments before she collapsed while waiting to get tested for Covid-19 infection, at MMG hospital, on April 21, 2021 in Ghaziabad, India.
Sakib Ali/Hindustan Times via Getty Images
  • Doctors in India say Covid-19 patients have unusual symptoms that could be due to the Delta variant.
  • They include gangrene and hearing loss.
  • There aren't enough sequencing tests sent to labs to know if these are unique to the Delta variant.
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Doctors in India claim that the highly infectious Delta variant could cause unusual symptoms such as gangrene and hearing loss, which they say are becoming more common in Covid-19 patients of all ages.

Alarming details of the symptoms were reported by Bloomberg on June 7 and followed up by the Daily Mail and Daily Mirror in the UK, where the Delta variant now accounts for 91% of new Covid-19 cases.

The highly infectious variant has spread to 67 countries and is becoming more common around the world. But, with fewer cases in India sequenced, there isn't enough data to know for sure whether the symptoms are unique to the variant, or are caused by Covid-19 more generally, which has already been linked to unusual symptoms such as diarrhoea and blood circulation issues.

The Delta variant is estimated to be 60% more infectious than the Alpha variant. It also has mutations that mean it can partially avoid the immune response.

Dr. Ganesh Manudhane, consultant cardiologist at Seven Hills Hospital in Mumbai, told Insider that he used to see four patients a year who had small blood clots causing gangrene, a serious condition where a loss of blood supply causes body tissue to die. Now it's one person every week, he said.

"I suspect it could be because of the Delta variant, because of the increased number of cases," Manudhane said - but he added that he hadn't genetically sequenced the patient's coronavirus tests to check for the Delta variant, which has become the most common Covid-19 variant in the country since first being identified there in October.

Dr. Abdul Ghafur, infectious disease consultant at Apollo Hospital in Chennai told Insider that he had experienced far more cases of people with Covid-19 presenting with diarrhoea than in the first wave in 2020.

But "all of the inferences from local doctors across the country were based on their clinical experience and not on any published data," he said.

It isn't clear how many people in India are infected with Delta compared with other variants. It is one of three similar virus strains that all originated in India.

Some statistics group these three together, and not all positive coronavirus tests are sequenced in the lab to check for variants. As of April, 0.75% of all India's cases were sequenced, according to a report in Nature. The country has had 29.45 million recorded cases since the pandemic began.

This lack of data is holding back doctor's understanding of the variant.

Ghafur added that "despite having the second highest number of [Covid-19] patients in the world, India's premier research institute, the Indian Council of Medical Research, hadn't conducted any scientific studies of value."

Anurag Agarwal, director at the Institute of Genomics and Integrative Biology in Delhi, told Insider that there was no clear link between the Delta variant and atypical symptoms.

Agarwal said the rise in people with atypical symptoms may be because of the increases in overall Covid-19 cases in India, rather than the rise of the Delta variant.

Neil Ferguson, director at the MRC Centre for Global Infectious Disease Analysis at Imperial College London, said at a briefing in the UK on Wednesday that, when a large number of people get sick, there can be a spectrum of rare conditions that aren't typical at all.

Dr Jeffery Barrett, director at the Covid-19 Genomics Initiative at the Wellcome Sanger Institute, UK said at the same briefing that the UK processes up to 20,000 tests each week.

INSACOG, a group of research labs that conducts India's sequencing, said it had sequenced more than 10,000 samples since it was set up in December.

Barrett told the briefing there was no data to suggest the Delta variants caused different symptoms to other variants.

A health worker takes a swab from a man's nose through a glass shield (for safety) in New Delhi, India, on August 8, 2020. Rapid antigen tests for COVID-19 are being provided by the Indian government for free.
Pradeep Gaur/SOPA Images/LightRocket via Getty Images

Black fungus

Black fungus isn't a symptom of coronavirus but a complication that occurs during the weeks after infection. Doctors in India have anecdotally associated it with the Delta variant.

Dr. Harsh Vardhan, India's health minister, said Monday that there were more than 28,000 recorded cases of black fungus infection that occurs in people with compromised immunity or diabetes. Of these, 86% had had Covid-19.

The link between black fungus and suppressed immunity or diabetes is not proven - but it's been suggested the high numbers of both in India could explain the number of cases of it.

Ghafur said he believed the Delta variant was most likely the cause of the rise in black fungus cases.

"India has always been the diabetes capital of the world and use of [immune system suppressing] steroids was rampant in the first wave,'' Ghafur told Insider. "The only difference this time is the Delta variant."

Dr Shailesh Kothalkar, an ear, nose, and throat (ENT) surgeon at Seven Star Hospital in the western city of Nagpur, told the Telegraph that the Delta variant was "causing damage to the beta cells in the pancreas, which produce insulin and regulate blood glucose levels."

"We need more investigation into this but [...] around 40% more patients are developing diabetes after having COVID-19 during this second wave," he said.

Professor David Denning, a professor of infectious diseases at the University of Manchester and chief executive of the Global Action Fund for Fungal Infections told the Telegraph: "It's possible that a different variant would produce more disruption of the lining of the nose or the lungs… and then that would allow fungus to get in more easily."

"But it's a bit tenuous," he said.

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