India reported a record daily rise of 83,883 coronavirus infections on Thursday, taking its total to 3.85 million cases, just as the country pushed ahead with attempting a return to normality and kickstarting its economy.

India now has the fastest growing Covid-19 infection rate in the world, and is only 100,000 cases behind Brazil, the second worst-affected country in the world. Experts are predicting that the south Asian nation will soon overtake Brazil (4 million) and then the US (6.1 million) to hold the dubious title of having the highest number of cases globally.

Shahid Jameel, a virologist and CEO of the Wellcome Trust/DBT India Alliance, said that the situation in India did “not look pretty”, adding: “Of the three top countries only India is showing a rising curve. This is a matter of grave concern and there is an urgent need to reverse the trend.”

Jameel placed much of the blame for the rampant spread of the virus on public apathy, which he said arose from “the constant narrative from central and state governments of rising recovery rates and low mortality”. He said this was a false depiction of the situation on the ground.

“People are not using the only scientifically proven methods to limit transmission: wearing masks properly in public and maintaining safe distancing,” he said.

The steep upwards trend, whereby the number of cases in the capital, Delhi, has increased by 50% in the past month, comes as India enters its “unlock 4:0” phase. Services such as metros will resume this week and later this month gatherings of up to 100 people will be permitted at sports, entertainment, cultural, religious and political events.

India went into a strict lockdown mid-March while rates of infection remained low. But over the past three months, rates of infection – even in states such as Kerala, celebrated for successfully containing the virus – have increased with an increasing momentum as the country has reopened.

The focus of infection is shifting from the big cities to rural areas, where two-thirds of new cases are now being reported. While the virus tends to spread less quickly in rural areas, this is still a cause for concern as 86% of people outside cities have no health insurance, only 20% of doctors serve in rural communities, and only 37% of government hospital beds are in rural areas.

The Indian government has continued to downplay the spread of the virus and emphasised instead the need to get the economy moving again. This week India reported a 23.9% drop in its GDP over the past quarter – the greatest recession it has suffered since records began in 1996. It is the worst-hit major economy. And with so many Indians working in the informal sector, the figure was likely to underestimate the country’s hardship, economists said.

The Indian government has attributed the record-breaking rise in cases to increased testing, with more than a million tests a day being done. But still only 45m tests have been carried out in a population exceeding 1.3 billion people. There are also concerns that about half of the coronavirus tests are rapid antigen tests, which have a high false negativity rate, indicating infections could be worse than official figures suggest.

“The infection is spreading faster and faster across India, entering new territories, and the ramped-up testing is just giving us a greater ability to detect those cases,” said Prof K Srinath Reddy, President of Public Health Foundation of India (PHFI). “In the big cities where it came in earlier, like Bangalore, Delhi and Kolkata, we are expecting it to settle down by the end of September, but the challenge will then be places where the virus arrived later. So I don’t see the pattern for India as a single peak but as a mountain range with many foothills that will continue for many months to come.”

As the official death toll continued to rise by over 1,000 a day, reaching a total of 67,376, India’s health ministry claimed that the country had one of the lowest coronavirus fatality rates in the world, at just 1.76% compared with the global average of 3.3%. While India’s young population and undercounting of deaths are believed to be factors, they do not fully explain India’s apparent high recovery rate.

In a statement, the union health ministry said: “While the global average is 110 deaths per million population, India is reporting 48 deaths per million population. The comparative figure for Brazil and the UK is 12 and 13 times higher, respectively.”