Major player Smitech (Asia) sold 250,000 digital thermometers here last week, five times the number it sold last year. Another, Futron Electronics, ordered half a million digital thermometers last week. All but 500 have been sold.

'Everyone is coming to us to buy in bulk and many are paying cash upfront,' said Futron's managing director James Lee. His company sold 48,000 such thermometers last year.

Ministry of Trade and Industry figures show that last year, Singapore imported about 180,000 thermometers, including industrial thermometers. Most of them were shipped from China, countries in Europe, the United States and Taiwan.

The increased demand has led to shortages, said suppliers. Stocks are low everywhere - in pharmacies, supermarkets, and even schools, which require students to carry personal thermometers.

'Everyone the world over is buying a thermometer now,' said Smitech managing director Christopher Koh. He said he is out of stock because factories overseas are short of raw materials.

'Don't forget we are talking about the whole world demanding the product now.'

A Guardian Health & Beauty spokesman said its chain is 'out of stock of thermometers in many stores'. He added that sales are up 20 times.

It is the same at Unity, which saw sales surge by 22 times. Watsons Personal Care Stores said sales have gone up by over 100 times since the virus broke out.

'We are making every effort to ensure we get stock into our stores as soon as possible,' said the Guardian spokesman. He said 24,000 oral digital thermometers would be in stores by Friday. 'We expect these to be snapped up very quickly and have made provision for further shipments to be in over the coming days and weeks.'

Read the full story in Wednesday's edition of The Straits Times.