Another 4 Weeks Of CMCO ?! Also...A Few (Further) Thoughts On Foreign Worker Community Testing

The CMCO has been extended by another 4 weeks. I think it will give us time to assess the impact of so many people going back to work, i.e. will we be able to maintain a “steady” number of daily cases or will there be exponential growth.   We are already seeing some impact where the foreign workers now constitute a bigger portion of the number of daily cases.

Date - May	Number of daily cases
	Foreign Workers	Malaysians	Total
7	30	9	39
8	57	11	68
9	45	8	53
10	49	18	37

I think the news so far is about the foreign workers spreading it to their Malaysian co-workers.  Or at least that is the impression from the clusters reported.  I have yet to come across any clusters where the transmission is from foreign workers to Malaysian customers/visitors.  We all should be worried when this happens.

Designed by Freepik

Because of this, there have been many comments about testing foreign workers. There was even one yesterday where the MP of Klang asked for extending the mass testing of foreign workers to low-cost housing residents.  I can only conclude that not many of our politicians understand enough about the virus and/or our capacity to manage it.

• Don’t they understand that we have limited testing capacity – the data shows about 9,000 daily tests for the past week.  At this rate, I have already said it would take 10 months to test all of them.
• Secondly, don’t they understand that the tests have to be repeated.  Just because a person is tested negative one day does not mean that he cannot get infected the next day. 

So with limited capacity and repeated testing required, there is no way we can test all foreign workers. But all is not lost.  The answer – random testing.  This random testing or sampling technique has been successfully employed for quality control in many factories and by market research companies.  It is not some secret technique. 

MOH is already doing targeted testing.  I think the target is chosen based on the clusters detected.  But this is reactive.  We need to complement this with random testing so that we can identify potential new clusters.  

How can we gauge whether MOH testing of foreign workers is effective?

• MOH used the detection rate (no of positives divided by no tested) as an indicator of whether there is sufficient testing.  WHO has 10% as the standard.  Based on the statistics we have a 4.7 % detection rate for the foreign workers c/w 2.4 % for just the Malaysians.  So we are doing better than what WHO has set for even the foreign workers
• If you look at the % of the respective population being tested, depending on what is your view of the foreign workers' population, we probably are testing a higher % of foreign workers c/w Malaysian
• In terms of number of tests per million population, both the testing of foreign workers and Malaysians places us somewhere in the top 1/3 ranking (if all the countries tracked by Worldodometer are ranked by number of tests per million population)

Items	Foreign workers	Malaysian
Number tested	24,125	232,812 (a)
Total population	2 – 4 m	31.5 m
% of pop tested	0.6 % – 1.2 %	0.7 %
Number of positives	1,132	5,523
Positives % of tested	4.7 %	2.4 %
Number tested past 4 days (b)	1,786	33,001

Notes

a) Assumed that the total tested are just for Malaysians and foreign workers ie assume that there are no international travelers tested

b) Between 6 May and 10 May

  

So I would conclude that we are doing OK in terms of testing the foreign workers.  The only negative news is that the ratio of foreign workers being tested to Malaysians over the past 4 days is half of that over the past 4 months.  I interpret this to mean that more foreigners were tested during the MCO period c/w the past 4 days.  This should not be surprising since there were many EMCO areas (One City, Selangor Mansion, etc) that were mainly residences of foreign workers.

If we take the detection rate as the gold standard, it means that we will have to double the numbers of foreign workers to be tested c/w Malaysians.  One way to do this is for employers to send about 0.1 % of its foreign workers for testing every week.  So if an employer has 100 foreign workers, this means sending one every 2 - 3 months for testing.  This would be equivalent to testing 2,000 - 4,000 foreign workers every week, about the average weekly testing rate for the foreign workers during the MCO.  The main difference is that we will have some form of randomized testing with this plan, be affordable and be within our testing capacity.  This employers' plan together with the targeted testing of MOH would enable us to double the testing of foreign workers. 

- - - - - - - - - - - - - - - - - - - - - - - - - - -

Be fearless to get more to Stay Safe, Share this Blog

PS: This blog is for me to better understand COVID 19 as this will impact my investments. If you are also into equities, follow me at i4value.asia

Disclaimer:  I am not an epidemiologist, healthcare worker, pharmacist or staff in the Ministry of Health, but rather is someone with a strong interest in numerical analysis.  The content is an attempt to understand what is happening in the battle against Covid 19 from a data-based perspective. The opinions expressed here are based on information extracted from readily available public sources but I do not warrant its completeness or accuracy and should not be relied on as such.