Positivity rate down to 15%; Centre ups caution

India’s test positivity rate for Covid-19 has fallen to 15.2 per cent between May 13 and May 19 after reaching nearly 22 per cent in the first week of May, revealed the health ministry data. Positivity rate had been consistently increasing for 10 weeks since February and started to decline in the past 10 days.

The central government has also increased the caution level in its latest advisory by recommending double masking, wearing masks at home, and also stating that aerosols — one of the key transmission modes of the novel coronavirus — can be carried in the air for up to 10 metres.

The advisory, released by the office of the Principal Scientific Advisor K Vijayraghavan, while suggesting proper airflow and ventilation in indoor spaces, has also cautioned against surface transmission, advising frequent disinfecting of high contact points, such as door handles, light switches, tables, and chairs. “Even one infected person showing no symptoms can release enough droplets to create a ‘viral load’ that can infect many others,” said the advisory.

The health ministry, quoting an international study, said one person can infect up to 406 people in 30 days if he does not follow any physical distancing. This number can be brought down to 2.5 by reducing physical exposure.

Eight states continue to have more than 100,000 active cases. Of these, all - except Tamil Nadu - are seeing a declining trend in active cases.