Covid-19 recovery rate crossed the 40 per cent mark for the first time in Bengal on Thursday despite a recent surge in the number of patients in the wake of a huge influx of migrant workers and others stranded elsewhere in the country during the first three phases of the lockdown.

The state reported 368 new cases on Thursday and 345 (around 94 per cent) of them were in districts which were experiencing a high volume of returnees.

The total cases rose to 6,876 from 4,536 a week ago and 1,344 a month ago.

But the release of 188 infected persons following cure in 24 hours till 9am on Thursday took the total number of recoveries to 2,768. The total number of cured cases has seen a rise of over 10 times in one month.

“Our recovery rate was 19.64 one month ago. Today, it increased to 40.25. This doubling, amid a phase of spike in the number of cases, is a heartening indicator,” said a Bengal minister.

While Calcutta reported the most recoveries with 996, Howrah and North 24-Parganas have total cured cases at 467 and 318, respectively.

Another positive element of the state’s Covid-19 stats, the minister said, was a persistent rise in the number of tests. With 9,606 tests reported on Thursday, which was yet another record, Bengal’s tests per million count rose to 2,687.

The total number of tests increased to 2,41,831 and the 2.5 lakh tests mark is likely to be surpassed on Friday. A month ago, Bengal was recording around 2,500 tests a day, with 306 tests per million and a total test count of 27,571.

“While testing has seen a quantum leap, the positive confirmation rate has been deteriorating slightly over the couple of weeks or so because of the rising number of patients,” said the minister.

The positive confirmation rate — the percentage of people found infected among those tested — deteriorated from 2.58 a week ago to 2.84 per cent. An increasing positive confirmation rate is indicative of higher levels of Covid-19 spread.

However, the rate improved considerably from 4.87 per cent over a month.

The state now has 42 Centre-approved laboratories for Covid-19 testing with Purulia Government Medical College and Hospital receiving the nod on Wednesday.

The death toll directly from Covid-19 reached 283 with 10 fatalities being reported on Thursday. The state government had reported the death of 72 Covid-19 patients from comorbidities till April 30.

Calcutta accounted for 234 of the 355 total deaths.

Bengal now has 11,205 quarantine facilities for people who returned by Shramik Special trains. Those centres have 1,36,600 boarders. This is over and above another 1,48,359 people under home quarantine and 20,662 at 582 other state-run quarantine facilities.

“The institutional quarantine numbers rose by nearly 32 times and the home quarantine numbers by around 16 times since May 8, after which the returns went up,” said the minister.

“But there, too, the good news is that another 1.97 lakh people have already completed quarantine successfully,” he added.