Dark Clouds On The Horizon ?

Designed by Freepik

Based on the past few days of daily cases, we estimated that for week 9 of the MCO, we will have an average of 32 cases per day c/w an average of 50 cases per day the week before. Are we seeing a declining trend?

I am afraid that there are some dark clouds on the horizon.  I think we have about 377 potential cases from the Tahfiz, Market and Returnee groups as tabulated below.  This is even before including the potential cases from the Tabligh cluster. 

The 377 projection is based on the people that have yet to be tested and assumes the same historical positive test rates for the respective groups.   I would like to think that the actual number of infected would be lower as it has been some time since these groups have been identified and some of those infected who were asymptomatic may have already recovered. 

Groups	No still to be tested	No infected at same % positive rate
Tahfiz	6,13	295
Market	7,539	68
Returnee	1,277	14
Total	19,878	377

As for the Tabligh group, MOH had been reporting an increasing number of people screened even though the index event was held at the end of Feb 2020.   FYI, there were 220 cases from the Tabligh cluster over the 19 days period from 28 April to 17 May so it is not a small number.

Date              Cum No from Tabligh cluster screened

28 April                      32,122

14 May                       38,679

17 May                       38,911

I suspect that the inter-state travel restriction and as well as the advice to keep the Raya visits low is because of the potential cases from the Tahfiz and Tabligh groups.  

The only positive news is that the total due to community spread over the past 3 months is 1,717 cases equivalent to 21 cases per day. 

The basis for the above projection is the table below where I have tried to reconcile the number of cumulative tests reported by Worldodometer as of 17 May 2020 with those of MOH targeted groups.  Of the 8 targets, there was no information on the testing and/or number of cases for the senior citizen group.  Ignoring the senior citizen group, we can draw the following conclusion about the targeted groups

• They accounted for 69 % of the total cases
• They accounted for 35% of the testing

Groups	Total tested (a)	Total positives	% positive (g)	Population
1.Tabligh	38,911	2,375	6.1	16,000 (b)
2.Tahfiz	13,636	658	4.8	19,771
3.Markets	29,594	259	0.9	37,133
4.Returnee	36,200 (j)	390	1.1 (j)	37,477 (c)
5. Foreign workers	26,425 (d)	1,037	3.9
6. Healthcare	11,470 (e)	65 (e)	0.6
7. Other clusters (h)	NA	381
8. Emergency surgery (i)	8.528	12	0.1
9. Balance/EMCO	278,499 (f)	1,717	0.6
Total	443,263	6,894	1.6

I cannot explain the balancing figures (ie group No 9) as the % positive looked very low relative to the % positives of other targeted groups.  The balance refers to community spread, EMCO areas and other clusters not specifically mentioned here.   Note the following

• I had assumed that the number of tests reported by Worldodometer refers to the tests carried out to detect new cases and exclude those for re-testing patients under treatment, etc.  I understand that out of our 26,700 daily test capacity, a significant portion is for re-testing of patients, etc and hence can account for why the actual daily number of tests for yesterday was only 9,127 c/w the capacity. 

• For groups 1 to 6, MOH actually reported the number of people screened which I interpreted to be equivalent to the number of tests i.e. 1 screen = 1 test.  I could be wrong.

•  Not all the information for the groups referred to the same date so there could be some counting error from this. 

Can anyone throw more light onto this breakdown?  Am I wrong to interpret the number of people screen = number of tests carried out?

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

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

Notes

a) As at 17 May unless stated otherwise

b) Supposedly the number of people who attended the Sri Petaling event.  The number tested included contacts

c) Total quarantined as at 18 May of which 29,279 have completed their 14 days quarantine and 390 tested positives

d) There could be double counting for the total tested with those in the Markets clusters although the total positives seem to be an independent figure

(e) As at 12 May.  This is inconsistent with the 28 April report of 6,838 screened with 372 positives (5.4 % positivity).  If we assumed the 372 positives, we would have a lower balance figure.

(f) Assume that the foreign workers are deducted from the total

(g) Detection rate defined as number tested positive divided by total tested

(h) These are clusters that are clearly not linked to the other groups listed ie Church, Wedding, Case 26, Italy = 381 as per Malaysiakini.  There is no report on the number of people in these clusters that were screened

(i) MOH reported that all those emergency cases in the govt hospitals needed to be screened before surgery

(j) The % positivity was based on 28 April report and was used to derive the number tested

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. 

__,_._,___

ReplyForward