Covid patients infected with the Indian variant are getting sicker more quickly than in previous waves, doctors in China have claimed.
In the city of Guangzhou, where the mutant strain is known to be spreading, medics say about 12 per cent of patients become severely ill within four days of symptoms starting.
The proportion had previously been as low as 2 or 3 per cent with the original Wuhan virus and the variant which first emerged in Kent and went on to become world-dominant.
The testimonies in China add to a growing body of evidence that the so-called Delta strain is not only far more virulent than previous versions, but also more dangerous.
In Britain, officials estimate the strain is twice as likely to cause hospitalisation than the Kent strain, and is at least 60 per cent more infectious.
UK experts say younger people also appear more likely to be admitted with the new variant, due to a combination of fewer young people being vaccinated and because the strain seems to pose a greater risk of severe illness.
But British doctors have not mirrored any claims about infected patients becoming sicker quicker.
Some scientists believe symptoms of the virus have become milder since the variant began to take off, which may be down to younger people — who are less vulnerable to the disease — getting infected.
Guan Xiangdong, director of critical care medicine at Sun Yat-sen University in Guangzhou, said the amount of Indian variant virus detected in the body rises to higher levels and declines more slowly than with previous strains.
This could partly explain why the mutant virus is more infectious, with patients coughing out more viral particles, and more deadly, because the immune system has to fight off a larger amount of the disease.
Cases in Guangzhou: The city in China’s southern Guangdong province has seen a slight uptick in cases since late May after an outbreak of the Indian ‘Delta’ variant. Source: John Hopkins University
It was first detected in a 75-year-old woman on May 21. Since then, the province has seen more than 200 symptomatic Covid cases. China does not class a patient as a confirmed case if they don’t have any symptoms. Source: John Hopkins University
Authorities in China’s southern Guangdong province are carrying out mass testing and have rolled back lockdown restrictions to curb an outbreak in Guangzhou.
The city’s latest wave of cases is being driven by the Indian variant which was first detected in a 75-year-old woman on May 21.
Since then, the province has seen more than 200 symptomatic Covid cases. China does not class a patient as a confirmed case if they don’t have any symptoms.
Checkpoints have been set up to monitor movement in and out of parts of Guangzhou and flights have been grounded in the city and neighbouring Foshan to get a grip of the latest outbreak.
An extraordinary testing blitz has also been launched in both cities, with 42million swabs carried out in three weeks — almost enough to vaccinate every resident twice over. The cities have a combined population of 28m.
Guangdong province recorded seven new cases yesterday, and the average number of daily infections is currently sitting at 12.
Professor Guan told state-run media last week the symptoms in patients infected with the Indian variant are different to older strains.
He said eight in 10 symptomatic patients in Guangzhou, in China’s southern Guangdong province, developed a fever.
It is not clear how this compares to previous waves in China but it is in line with findings from a major UK symptom tracking study by King’s College London.
The rolling British study found that the mutant strain caused symptoms more akin to a ‘bad cold’ than the typical Covid symptoms.
Professor Tim Spector, who runs the research, said Indian variant patients were more likely to report headaches, sore throat, runny nose and fever.
Previously the most common signs of the disease were a continuous cough, or loss of appetite or smell.
Officials in China have not said how many of the new infections from the Indian variant have been in people already vaccinated.
There has been questions about how effective China’s vaccines are and the nation has been reluctant to publish data from trials of the jabs.
But there is evidence in the UK that vaccines work less well against the new variant, particularly after just one dose.
Public Health England’s latest analysis, published last week, found that a dose of either AstraZeneca or Pfizer’s vaccine was about 33 per cent effective at stopping infection from the Indian variant, compared to around 50 per cent against the Kent one.
Two doses provided more than 80 per cent protection against the Delta strain, slightly less than for the ‘Alpha’, or Kent, version (88 per cent).
