Spatial distribution of Covid-19, a modeling approach: case of Algeria

The objectives of this study are to modeling the spatial distribution of Covid-19 at the regional scale (Case of Algeria) based on geostatistcal study of covid-19 cases spatial distribution and Hybrid Kriging. The data analysis of a published ocially Covid-19 reports by the Algerian Ministry of Health. a map of contamination by covid-19 has been obtained and a new model of risk evaluation has been developed and proposed to predict the propagation of this pandemic in Algeria. To conclude this work show areas with high population density are most exposed to virus propagation and death arising. Simulation show that infection by Covid-19 will arise to 14 000 cases in Algeria in the last of April also the velocity of transmission of this virus is rapid. Map obtained help the local authority to manage Covid-19 infections at the spatial scale.


Introduction
Pneumonia of unknown cause was detected in Wuhan City, Hubei Province, China -the seventh-largest city in China with 11 million residents. As of January 23, there are over 800 cases of 2019-nCoV con rmed globally, including cases in at least 20 regions in China and nine countries/territories (Dong E  The international ratio infected/death cases is across 5.54% contrariwise the Algerian Ratio is higher than the International standard 12.15 %.
Our study aims to establish a map of risk of corona virus in Algeria. By using data about infected cases from two spaced date, the model developed gives a prediction of infection risk at the regional scale. The methodology developed can help the government to manage the Covid-19 crisis at the spatial planning of the crisis.

Area Of Study
Algeria is located along the North African coast (Fig.1), bordered to the east by Tunisia and Libya, to the southeast by Niger, to the southwest by Mali, and to the west by Mauritania and Morocco. It is the rst largest country in Africa, with area about 2.7 millions km², coastline of 1200km.
Algeria holds a special place in the Mediterranean basin with its geostrategic position and its demographic and economic weight. Pcovid: is the predicted covid-19 cases; Popdensity : is the density of population by km².
A new model is derived from the analysis of cases, to predict evolution of contamination risk in function of time ( Figure.3). Analysis concludes that very person can contaminate 4 people.
Insert Figure 3 here.

The model obtained have an exponential form, it is given by the equation (eq.2):
Pcovid : is the predicted covid-19 infection; t: is time given in days By taking an incubation time of 14 days, we suppose that every person can contaminate 3 persons we can establish a time function of Virus propagation in Algeria.
A simulation of the actual situation by taking into account our scenario show that the cases of Covid-19 in Algeria can be arise from 1400 cases actually to 14 000 infections cases.
The analysis of these results allows us to formulate a new model to predict the Covid-19 infections. The new equation was given as below: Map in gure.4 show the spatial variation of Covid-19 cases in Algeria as reported by the national ministry of health.
Insert Figure 4 here.
The spatial distribution of infected cases shows that the center of the infection is localized in the North of Algeria. The isolation of the epicenter of the diseases can reduce the propagation along the country.
The velocity of propagation is high which can damage the health structure and the capacity of the hospital to manage the arising cases (Shannon 2020, Wendy 2020). Our work gives a global idea about the propagation risk of this virus. A lot of parameters can accelerate this velocity (Road tra c, density of contact, space markets and commercial centers, Administrations and services local) all of this kind of structures can accelerate the propagation of contagious virus (ACSS 2020).
In this work a map of spatial covid-19 was established to demonstrate the evolution of this contagious virus in Algeria. The map show regions with low evolution are located in the south of the country. Regions of medium evolution are located in the high steppes and nally regions of high propagation risks are located in the North.
The high propagation of this virus in the north of the country is due to the high population density, high transport and air tra cs .These factors are the primary causes of the rapid evolution of this dangerous contagions virus.
In conclusion, the velocity of propagation of COVID-19 is high which need an intensi ed efforts to reduce the contagious and contamination Risk. This study illustrates a geographic analysis of the propagation of this virus.
The simulation shows a high propagation of this virus in Area with high population density. The simulation also show that the number of cases will achieves 14 000 cases in 30/04/2020. Map show that COVID-19 epicenter is localized in the north of the region. Algerian authority work hardly to reduce the propagation of this virus. The efforts of all sectors in Algeria concentrated to reduce the death number by application of Chloroquine protocol which gives good results according to the clinical recovered persons.
The Algerian ministry of health a rms the good results of this medicaments type.

Con ict of interest
The authors declare that they have no con icts of interest.