Are we losing control over COVID-19?

Note:  The majority of the posts with the "Risk" label invariably looks at the current situation.  As such the current analysis supersedes all the previous analysis regarding the questions of whether there is any cause for concern or whether the risk of catching Covid-19 has increased.  Specifically, I have taken offline the 7 and 8 May 2020 posts. 

Over the past 4 weeks, we seemed to have an average of 100 Covid-19 cases per week. 

 

If you look at the chart showing the number of weekly cases since the end of the MCO, you can see that the number of weekly cases seems to be on an increase c/w that in late June/early July 2020. 

There has been recent news about how other countries that previously had the virus under control eg New Zealand, seemed to experience a surge.

So the question is whether Malayais is losing control over the virus?

When you separate the cases over the past 4 weeks into imported and local transmissions we find that about 60 % is locally transmitted.  This is equivalent to about 60 cases per week due to local transmission. 

Currently, we have a mandatory quarantine of all those coming into the country so I would imagine that we have these under control.

But what about the local transmissions? 

Under Control

There are different ideas of what “under control” means in the context of Covid-19.  

• New Zealand seems to interpret it as eliminating the virus

• President Trump thinks that with 1,000 daily deaths it is under control

I have not seen any definition of this for Malaysia.  A Google search for “Malaysia Covid-19 under control” showed the following

• On 7 June, our PM said that the virus is under control. There were 37 cases during that week. Of these 13 were due to local transmission. 

• On 11 Jul, our DG of MOH stated that “Covid-19 infections are well under control in Malaysia, as shown by the low number of positive cases detected during pre-surgical screening”.  As of July 10, he said a total of 60,952 pre-surgical samples have been taken, and 21 cases were tested positive (0.03%).

So should we be looking at "under control" from these numerical targets only?  If so we have failed as shown below!

Current situation

A statistical comparison of both situations shows the following.

• We currently have 60 cases per week due to local transmissions c/w to the 13 cases during the week when our PM made his announcement.  This is more than a fourfold increase

• From 2 to 15 Aug, we had 8 cases detected during pre-surgical testing (Source: MOH daily press release).  Compare this with the 21 cases as of Jul 10.   

While I don’t have the number of pre-surgical testing carried out from 2 to 15 Aug to compute the positivity rate, the number of cases detected over a 2 week period seemed very high compared to that detected over the 4 to 5 months period. 

If we go by the PM and MOH statements, the numbers indicate that we are no longer “under control”.

Of course, there has not been any official definition of what "under control" meant.  Historically there were also references to

• Keeping below a certain R0 target

• Flattening the curve concept

So how do we perform if we follow these criteria?

R0 reference 

R0 is an epidemiological term that indicates how contagious an infectious disease is.  It is also referred to as the reproduction number ie how many times it reproduces itself.  

A value that is greater than 1 means that the virus will spread whereas a value of less than 1 implies that the virus will eventually be eliminated. 

On 23 Jul, the DG of MOH said that Malaysia may see a surge in the number of new COVID-19 cases soon if the infectivity rate or R-naught (R0) exceeds 1.6.  The current R0 had increased to 1.36 compared to 0.3 during the Conditional Movement Control Order (CMCO) which ended on June 9.

I don’t know how MOH computes the R0 (eg does it cover only the local transmission).  But during the 2 weeks prior to 23 Jul when the DG made his statement, we had 85 cases in total due to local transmission.  

Contrast this with the 113 cases over the past 2 weeks.  Using a simple factoring, R0 would have exceeded 1.6 currently. 

By this measure, we are losing control.

Flattening curve

The concept of flattening the curve is to keep the number of cases below both the treatment, treatment  and contact tracing capacity.  This was the initial objective of many countries when the virus first hit them.

Malaysia also adopted this approach.  However, I could not find any specific mention of the target number of daily cases to signify that the infection rate is within the various capacities. 

Instead, we had other indirect measures as follows. 

Medical capacity

On 13 Aug, the Malaysian Deputy Minister of Health reported that the country has a total of 6,889 regular beds and 430 Intensive Care Unit (ICU) beds reserved for Covid-19 cases in 40 hospitals nationwide. 

Of these numbers, he said less than 15% of the regular beds and less than 5% of the ICU beds are currently occupied by Covid-19 patients.

“There are 1,364 ventilators available at Covid-19 hospitals and the utilization rate, including non-COVID-19 patients, is around 40% currently. 

In terms of laboratories, there are 58 labs across the country that can carry out Covid-19 testing. These labs have a combined capacity of 38,600 tests per day,” he added.

So we have under-utilized treatment capacity.  

This becomes more awesome when you consider that Malaysia hospitalizes all detected Covid-19 cases irrespective of whether they are mild or asymptomatic.  Contrast this with the US where only those mild cases are asked to stay at home.

Testing

We also have an under-utilized testing capacity.  

The chart below showed that over the past 3 weeks, there were an average of 9,000 tests carried out daily with 0.16 % positivity rates during this period

• This is slightly less than ¼ of our testing capacity

• This is almost double the daily tests conducted in April

• It is very much lower than the WHO standard of below 10% positivity rate

Malaysia is still having problems with the medical reporting system.  Private labs have not been able to provide daily test results.  This is led to days where zero tests were reported followed by large cases the following days.  

It should be pointed out that Malaysia has a targeted testing programme covering known clusters, EMCO areas, first liners, old folks home, pre-surgeries, and detention centres.  

The low positivity rates showed that sufficient testing is being carried out.

Contact Tracing

There have not been many statements by the govt about our contact tracing capacity.  

Anecdotal evidence seems to suggest that we are doing ok in this area in terms of SOP, clusters, and the contact tracing app. 

1) We know that the current SOP requires all outlets to record visitors details

2) In terms of clusters that emerged in Aug

• The worst-case has been 3rd generation transmission.  

• The biggest is the Sivagangga cluster with 45 cases. 4,643 have been traced and tested as of 9 Aug

• The second biggest was the Tawar cluster with 33 cases and 657 contacts traced and tested as of 15 Aug

3) The govt seems to have focussed on MySejahtera as the main contact tracing app.  It is now mandatory for all businesses to use this app.  I have come across a Codeblue article that said 1 in 5 people in Malaysia has signed up as of 24 Jul 2020.

They all point to a situation where we seem to be able to trace and isolate all those infected before they reached exponential growth.

My Historical Analysis

When it comes to medical capacity, the various authorities announcements seem to focus on utilization.

I think this is not very informative from a "control" perspective because utilization is a "derived" figure.  It is dependent on the number of daily cases detected and the number of cases that have fully recovered.

Since treatment may take 2 to 3 weeks, we could have a situation where the number of daily cases builds up at such a rate that the incoming to the hospitals exceed those discharging.  This will then overwhelm medical capacity.

So it is important to know this trigger point in terms of the number of daily cases so that action could be taken before our medical capacity is overwhelmed.

We want a preventive method rather than a reactive "flatten the curve" approach. 

Furthermore, this is complicated by the nature of exponential growth. So we need a "trigger number" to indicate that we are entering the exponential territory.

In my 2 May 2020 post, I estimated that if we have less than 30 daily cases (excluding the imported), we safe from exponential growth. 

These 30 cases should be sporadic cases ie not from one or two clusters.  By sporadic cases, I mean that we have not been able to identify the cause/source of the infection.  

We thus have another perspective to assess whether we are losing control.  Since we have yet to reach these 30 cases, I would argue that we have not lost control yet.

Conclusion

• The current number of cases is significantly higher than those when our PM and/or the DG of MOH announced that the virus is under control

• There is a possibility that the current R0 figure is above MOH target R0 for "under control"

• However, our medical and testing capacities are currently under-utilized.  Also, the number of cases seems to be within our contact tracing capability

• The current number of cases also seem to be below the trigger point for exponential growth

Looking at the above, we can conclude that we get different conclusions using different metrics.  

Because they are all not pointing in the same direction, I am inclined to conclude that we have not entered the "losing control" zone.  

There is still hope.

It is instructive to note that in my 7 May post (which I have since taken offline as it is superseded by this post) I referred to an article The New Yorker by Jim Yong Kim, former president of the World Bank, former director of WHO and currently advising Massachusetts on its COVID 19 strategy. 

He said that any country wanting to fight successfully has to do all the following 5 things simultaneously.

• Testing
• Contact tracing
• Isolation and quarantine
• Social distancing
• Treatment

Malaysia today is still pursuing the above 5 things and I think it should be another reason why the country has not lost control of the fight. 

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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.