According to data collated by statistics site Our World in Data, Singapore has conducted an average of 7.6 tests for each confirmed case since the COVID-19 outbreak started. This is compared to 18 test in Japan, 84.9 in South Korea, and 250.4 tests in New Zealand.
What the graph below tells us is that for every 7.6 COVID-19 tests conducted in Singapore, one will be positive. The data for Singapore is as of 1 June. We also note that the number of tests is different from the number of people tested, as one person may be tested more than once.
According to Our World in Data, Singapore’s test numbers are based on reports from the Ministry of Health on the number of people that have been tested and the number of swab tests that have been conducted, both of which the ministry started reporting on 10 April.
The site noted that countries with very few tests per confirmed case are unlikely to be testing widely enough to find all cases.
Singapore’s 7.6 tests per confirmed cases is still below the World Health Organisation’s recommendation of 10 to 30 as the benchmark for adequate testing.
In a World Health Organisation (WHO) briefing on 30 March, Dr Michael Ryan said, “In general where testing has been done fairly extensively we’ve seen somewhere between 3 and 12 percent of tests being positive…we would certainly like to see countries testing at the level of ten negative tests to one positive as a general benchmark of a system that’s doing enough testing to pick up all cases.“
Now, the Singapore government has repeatedly stated that the high number of positive cases in the country is due to extensive testing.
On 19 May, the Ministry of Health’s director of medical services Associate Professor Kenneth Mak said in a briefing that over 281,000 COVID-19 tests have been conducted to day on 191,000 unique individuals. That’s about 49,000 tests per million people being carried out in Singapore, he noted.
On 14 May, Minister for Manpower Josephine Teo had urged the public not to be “overly alarmed” as the number of positive cases among the migrant worker population in Singapore increases as this is due to “comprehensive” and “aggressive” testing being carried out.
She said, “Few countries have tested their migrant populations extensively; far fewer have undertaken to test all their migrant workers, as Singapore has.”
Even earlier on 27 April, Health Minister Gan Kim Yong said, “Our testing capacity for migrant workers is about 3,000 a day. We have not reduced it. Instead we have been increasing the capacity of testing of our migrant workers. The rate of testing has not slowed”
“A total of 21,000 migrant workers living in dormitories have been tested since the start of the outbreak. This means that 1 in 15 migrant workers in dormitories have been tested.”
On the same day, the MOH said in a statement, “To date, Singapore has tested about 2,100 per 100,000 persons. In comparison, the US has tested 1,600 per 100,000 and the UK 1,000 per 100,000. “
It added, “From an average of 2,900 tests per day in early April, we are now able to conduct more than 8,000 tests per day. “ (Note that the test capacity stated is different from actual tests conducted.)
However, all these statements and explanation from various ministers and the MOH do not quite tally with the graph above.
While it’s true that Singapore conducts a high number of tests per capita, we also have a higher percentage of positive cases in this country based on the population.
The extensive testing is also targeted towards people who are exhibiting symptoms, close contacts of infected patients, and those in high risk areas such as isolated foreign worker dormitories. Singapore is not simply testing everyone.
As such, what this Our World in Data graph likely indicates is that there might be cases within the community that have yet to be diagnosed due to how the tests are conducted compared to other countries.
As you can see in the graph, the number of tests conducted by New Zealand goes far beyond the number of confirmed cases.
That’s 250.4 tests for one confirmed cased compared to Singapore’s 7.6. So is Singapore really testing as extensively as the government says?