E-Paper
Bengal to start pool sampling to detect Covid-19 carriers
In pool testing, samples from two to five people are collected and tested in a single unit. If the pool tests negative then all individuals are regarded as negative. But if the pool sample is positive each person in the pool is tested individually to find out who is affected.
The West Bengal government has decided to start ‘pool testing’ to detect asymptomatic carriers of the Covid-19 disease. This will help to further ramp up the testing record of Bengal, which has been repeatedly drawing flak for its low rate of Covid-19 tests.
In pool testing, samples from two to five people are collected and tested in a single unit. If the pool tests negative then all individuals are regarded as negative. But if the pool sample is positive each person in the pool is tested individually to find out who is affected.
This helps to increases the testing capacities and saves time, money and manpower.
“In order to increase the capacity of the laboratories to screen more numbers of samples it has been decided to use pooled samples for screening of suspected Covid-19 cases in West Bengal,” read an order issued by the state government on Saturday.
A top official of the state health department said that pool sampling will be done for asymptomatic patients in those areas where prevalence of the disease is less than 2% of the population.
“Samples will be collected from asymptomatic patients during community survey and surveillance. Those suspects who have come in contact with Covid-19 patients and are living in areas where the disease has spread will not be included,” said the official.
Saturday’s order came a day after the division bench of Calcutta high court comprising Chief Justice T B N Radhakrishnan and Justice Arijit Banerjee heard arguments on a writ petition and asked the government to inform what action was being taken to tackle the outbreak and how it was determining the cause of deaths. It also wanted to know what the government was doing to stop the spread of the disease and protect medical staff and doctors following guidelines of the Indian Council of Medical Research (ICMR) and World Health Organisation (WHO).
Out of the 23 districts in West Bengal, at least 10 districts have not reported any case so far. Officials said that at least 81% of the cases are confined in urban areas with north and central Kolkata and urban areas of Howrah reporting the maximum cases. There is also a high prevalence of the disease in North 24 Parganas.
“We will take samples of five people in one pool. The ICMR has already issued some guidelines for pool testing and those would be followed,” the official said.
With allegations mounting that not enough tests are being done to detect Covid-19 patients in Bengal and numbers of persons infected with the deadly disease spiking every day, the Mamata Banerjee government had on Friday decided to test even the asymptomatic suspects who might be carriers of the virus.
Till April 17 in Bengal only 4,212 samples were tested. Compared to this Karnataka, Kerala and Madhya Pradesh had done 17,594, 18,029 and 20,298 tests respectively.
“The more you test, the more you can detect asymptomatic carriers. Random sampling and pool testing are ways through which you can ramp up your testing record. This is a welcome step and the need of the hour,” Kunal Sarkar cardiologist said.
