Modeling the Impact of Lock-down on COVID-19 Spread in Malaysia

After a breakdown notified in Wuhan, China in December 2019, COVID-19 is declared as pandemic diseases. To the date more than 13 million confirmed cases and more than half a million are dead around the world. This virus also attached Malaysia in its immature stage where 8718 cases were confirmed and 122 were declared as death. Malaysia responsibly controlled the spread by enforcing MCO. Hence, it is required to visualize the pattern of Covid-19 spread. Also, it is necessary to estimate the impact of the enforced prevention measures. In this paper, an infectious disease dynamic modeling (SEIR) is used to estimate the epidemic spread in Malaysia. The main assumption is to update the reproduction number Rt with respect to the implemented prevention measures. For a time-frame of five month, the Rt was assumed to vary between 2.9 and 0.3. Moreover, the manuscript includes two possible scenarios: the first will be the extension of the stricter measures all over the country, and the second will be the gradual lift of the lock-down. After implementing several stages of lock-down we have found that the estimated values of the Rt with respect to the strictness degree varies between 0.2 to 1.1. A continuous strict lock-down may reduce the Rt to 0.2 and accordingly the estimated active cases will be reduced to 20 by the beginning of September 2020. In contrast, the second scenario considers a gradual lift of the enforced prevention measures by the end of June 2020, here we have considered three possible outcomes according to the MCO relaxation. Thus, the estimated values of Rt = 0.7, 0.9, 1.1, which shows a rapid increase in the number of active cases. The implemented SEIR model shows a close resemblance with the actual data recorded from 10, March till 7, July 2020. Author summary Conceptualization, A.A.A; methodology, A.A.A, N.M; validation, A.A.A, N.M; formal analysis, A.A.A; investigation, N.M, A.A.A; resources, G.E.M.A, L.T; data collection, L.T, N.M; writing—original draft preparation, A.A.A, L.T, G.E.M.A, N.M; writing—review and editing, V.S.A, S.C.D, B.S.G, P.S, S.A.B.M.Z, N.M; visualization, N.M; supervision, V.S.A; project administration, V.S.A. All authors have read and agreed to the published version of the manuscript

Common symptoms of COVID-19 are cough, fever, sore throat, pneumonia, and 10 shortness of breath [4][5][6]. All groups of people can be affected by this illness; however, 11 about half of them needs a hospital admission due to medical problem backgrounds such 12 as high blood pressure, heart and diabetes [7][8][9]. 13 The COVID-19 disease spreads from an infected person to an uninfected person 14 through breathing small droplets from nose or mouth, expelled when the COVID-19 15 infected person coughs, sneezes, or speaks. These droplets do not sink to the ground nor 16 travel far. Thus, nearby people can also get infected when they first touch the surfaces 17 with virus droplets and then touch their face, eyes, nose, or mouth. Therefore, it is 18 advised to always wash hand too [7,10,11]. 19 The chronology of COVID-19 spread starts when China's Health Authority reported 20 a mysterious pneumonia found among 41patients from Wuhan city, on 31st December 21 2019. This first cluster is linked to the Huanan Seafood Wholesale Market [5,12,13]. 22 Accordingly, Wuhan city is placed under quarantine and followed by the whole province 23 of Hubei in the next days [4,13]. However, few days later China recorded its first case of 24 death [14]. The coronavirus case and even case of death also starts to be observable in 25 regions outside of China. Other than China, COVID-19 was also found to start having 26 outbreak in other countries, South Korea, Iran, Italy, and Spain. On March 11, the 27 WHO has declared COVID-19 as a pandemic [11,[14][15][16]. 28 As for Malaysia, the Malaysian authorities have initiated a thermal checkup at all 29 the entry points of the country since the reporting of the first wave of the virus. The 30 very first recorded case COVID-19 is linked to a male returning from Wuhan, on the 31 25 th January 2020 [17]. Following that, on 27 th January, all the travelers from Hubei 32 province are banned from entering the country. On 9 th February, the ban is extended to 33 include all travelers from Jiangsu and Zhejiang provinces [49] and on 5th March, 5. Closure of all public and private higher education institution (IPTs) and skill 48 training institutes. 49 6. Closure of all government and private premises except for essential services. 50 With the movement control order put in place since 18 th March, all citizens have been 51 prohibited from leaving the country and foreigners also prohibited from entering the 52 country. The movement control order was originally set to end on 31st March; however, 53 the order has been extended three times as additional two-week "stage"over the course 54 of two months. For the purpose of estimating the active cases in Malaysia, the various 55 stages are described as follows:  Control Order (CMCO), aims to relax the enforced regulations in order to reopen 76 the national economy in a controlled manner [44]. The regulations of the CMCO 77 were eased where most economic sectors and activities are allowed to operate 78 while observing the business standard operation. However, sports activities 79 involving large gatherings, social, community, cultural and religious events, as well 80 as all types of official events and assemblies are not permitted [44,45]. It is believed that any system that has intrinsic number of uncertainties, measurement 102 and time delays, such systems are very complex and difficult to predict. Currently the 103 most contagious corona virus has all such factors within itself and it has swallowed 104 already more than 284,000 lives. In the last few months, researchers from all around the 105 globe has suggested numerous models for predicting the behavior of COVID-19 curve two points. In most of the cases, this is generated using the dataset from census and 112 from hospitals. Whereas the compartmental model is based on ordinary differential 113 equations used in several cases such that [22][23][24].

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This is observed while doing literature survey that people have tried to predict the 115 Ro by any technical strategy hence in the same regard this paper presents the major 116 modeling schemes that are tried to predict the next upcoming months for specific 117 jurisdiction such that from 06 January 2020 till 11 May 2020. For this time interval 118 proposed manuscript identifies the top 10 frequent studies that may estimate the 119 reproductive co-efficient for this novel coronavirus (COVID-19) from all over the world. 120 It has been observed that very few models are available that focuses specific cities of a 121 country [23] [25] [?], whereas others are focused on entire country. In Table 1, it has 122 been seen that mostly the approaches are proposed for entire country and very few are 123 proposed for cities.

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It has been observed that very few research contributions were made to derive the 125 mathematical model universally applicable to individual countries or locality [24]. Some 126 of the techniques were based on Susceptible, exposed, infectious and recovered SEIR 127 approach [26] and some are based on exponential growth with an amalgamation of 128 statistical approach and stochastic representation [26]. Few estimation techniques are based on the epidemiological parameters which are 130 derived using an age-structured, location and model that uses data on specific contact 131 patterns [29]. Taking an example of Italy which had been affected by COVID-19 132 recently, people implemented the SEIR Model to compute the future response [37] by 133 varying the parameters and initial conditions. The same model has been adopted by one 134 of the researchers for computing the causalities in the United Kingdom [31]. SEIR

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Model has a great and efficient computational result, therefore, it has been used by 136 many researchers such that India [30], the data record most of the cases are collected 137 from John Hopkin's repository in the multiple time frames. In addition to this, several 138 research contributions were made in [31][32][33][34] using this SEIR model, therefore, the paper 139 also proposes the same model for computing the casualties in Malaysia.    in Malaysia. The first 3 cases were reported in Selangor state and 1 in Johor, later 159 followed by Kedah. Figure 3(b) shows the total death for January. Two states were first 160 to report first death cases in Malaysia, those are Johor and Selangor.  Figure 4(b). 165 Indeed few deaths were counted for February which is plotted in Figure 4(c control and also social distance was enforced.

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As shown in Figure 5 it represents the total number of confirmed cases based on 177 state and number of death reported. In Figure 5 Putrajaya. The Selangor cases were tacked back from the wedding which took place in 181 Bangi Selangor on March 6-7. It was reported this cluster was the second in recording 182 the number of cases after tabligh event. In this cluster, around 92 cases were reported, 183 from which 44 cases were reported from Hospital Teluk Intan. Even though MOH 184 believes, tabligh cluster is also linked with this cluster in spreading virus unknowingly. 185 In the month of April maximum number of confirmed cases were reported. As shown 186 in Figure 6(a) upto 6000 cases were notified. Figure 6  shows the major state where death cases were reported.

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Since it is required to understand the pattern of virus spread as there is no clinically 202 proven medication for this virus to cure. Hence, it is required to follow the social 203 distancing and actively practice MCO until June 2020. In this paper, the next section 204 will define how mathematically prediction can be developed to stay safe and how long 205 MCO should be practiced. The main assumption in this manuscript is no local cases infected from animal 219 transmissions, hence the initial cluster and the clusters that follow are from overseas. 220 Moreover, we assume that the immunity of the population is the same. Finally, we 221 assume that the natural death and birth have minimal impact on the course of 222 predication, thus, they are not considered in the calculation.

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In this paper, we also assume that the reproduction number Rt follows the strictness 224 of the prevention measures imposed by the government. Thus, the extension of the The reason behind using a mathematical modeling of infectious disease is to help inform 232 public health interventions, predict the future course of an outbreak and more 233 importantly, to evaluate the strategies to control an epidemic in order to promote 234 evidence-based decisions and policy [21]. According to the theory of compartmental 235 models, the population is assigned to compartments with labels (i.e. S; refers to 236 susceptible, E; refers to exposed, I; refers to infectious, and R; refers resistant or 237 removed). The candidates of the population may progress between these compartments 238 based on the characteristics of the infectious disease. In that context, the SEIR model 239 belongs to the compartmental models' family, which used to project how infectious 240 diseases progress and show the likely outcome of an epidemic [39]. SEIR model is 241 utilized successfully in estimating the number of infectious cases with pandemics such as 242 Ebola [22] and SARS [23].

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According to SEIR model, the population is classified into four compartments: 244 susceptible (S; at risk of contracting the disease), exposed (E; infected but not yet 245 infectious), infectious (I; capable of transmitting the disease), and removed (R; those 246 who recover or die from the disease). Then, the total population (N) is given by the 247 sum of the various compartments; N = S + E + I + R. The susceptible individuals who 248 have been infected first enter a incubation period (exposed), where during this period, 249 they are not likely to infect other individuals. The differential equations of the SEIR 250 model are given as [42,43].
The transmission rate (β) is given by: While the estimates of the infectious, exposed, and removed portions of the population 253 are given by the following differential equations [42,43]: where σ is the infection rate calculated by the inverse of the mean incubation period, 256 and γ is the recovery rate calculated by the inverse of infectious period.

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The estimation is carried out for Malaysia with the major outbreak on 10 March 258 2020, where the number of infectious reached 129. According to the typical SEIR model, 259 S was assumed to be the population of Malaysia. The initial number of cases as well as 260 the respective recovered cases on 10 March 2020 are also considered. The number of 261 exposed individuals is assumed to be 20 times the infectious individuals; E = 20 * I [46]. 262 According to [47], the infection rate (σ) was set as 1 = 5 : 2, where the denominator (5.2 263 days) is the average incubation period of COVID-19. The recovery rate (γ) is assumed 264 to be 1/18, where the denominator (18) is calculated based on the summing the median 265 time from infection to diagnosis plus the hospitalization period [48].

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In this paper, we follow the initial values of Ro published by [46] to estimate the predication implements a parallel Rt values, where R 0 is assumed to be 0.9, 2.6, and 3.1. 278 Figure 8 shows that the number of the active cases will continue to climb for the whole 279 time period, and the increase in the value of the reproduction number value Rt result in 280 an exponential growth of the number of active cases. According to this scenario, the active cases during this period set as Rt = 2.9, 2.1, 0.9, 0.7, 0.5, 0.3, and 0.2 for stage 0, 299 1, 2, 3, 4, 5 and 6 respectively as shown in Figure 9.

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The results shows that the Rt values is assumed to decrease gradually from 2.9 to   The second stage of the MCO (30 March to 14 April) was capable to reduce the Rt 334 value from 2.1 to 0.9. This show that the prediction matches the actual data and 335 accordingly, the peak of the active cases curve occurred in mid-April (anticipated by the 336 WHO). Similarly, the further extension of the MCO result in a noticeable decline in the 337 active cases curve, where by 12 May 2020, the estimate of the active cases is 1881 as 338 compared to 1410 obtained from the actual data.

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The paper also further extend the prediction to estimate the number of the active 340 cases till 8 th September 2020. In order to simulate the impact of the relaxation of the 341 RMCO, the paper used a sequence of various Rt values. recovery also was found to be high, exceeding 50%.

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The predictions made by this paper were aligned with the health authorities' source 352 July 14, 2020 14/21  It was reported by the government after the control of cases for till April 2020,

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another spike was notified in the month of April 2020 (last week) and June 2020(early 372 weeks), in which most of the cases were reported from immigrants as shown in Figure 9. 373 These all immigrants were kept in the detention center. This may conclude that 374 COVID-19 is not spread among Malaysian as these immigrants were all living without 375 following social distancing parameters.