Introduction
Over the past several decades, several new epidemics have been reported and emerged in particular areas, which have led to the spread of diseases such as: Ebola virus disease (EVD) caused by Ebola viruses, The disease was first identified in 1976 and still around. Zika (caused by the Zika virus) , Nipah (caused by the Nipah virus) , and coronaviruses (CoVs). Recently, a new type of viral infection has emerged in Wuhan, Hubei province, China, (Hui, D. S et al, 2020) and in general the genetically data and structurally this virus does not exactly match with the previous CoVs. The novel CoV strain 2019, Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (China-WHO Joint Mission, 2020). However it is believed, that the disease originated in the wild animal host (zoonotic origin) and was later transmitted to humans, the possibility that food is the source of the transmission is neither undeniable nor the right reason. Codon usage studies suggest that animal source such as bats are more likely to be the source of the onset and spread of the this novel virus(Dhama, Sharun et al. 2020). The disease was first identified on December 12th, 2019, and has since spread globally. The World Health Organization (WHO) has published two valuable news on two different dates, including the announcement: the first one revealed On 30 January 2020 that the corona virus outbreaks is a Public Health Emergency of International Concern (PHEIC) and on 11 March 2020 the second declaration published and revealed that the new CoV strain 2019 is a pandemic infection(Ali, Baloch et al. 2020), which it defines as ”global spread of a new disease”. The evidences of local transmission and spread of the disease has also become a dangerous ring, and many countries have begun to spread awareness across the country and most of the them have announced an emergency alert throughout the countries, and across all six WHO regions (Hui, D. S et al, 2020). According to various studies the most common symptoms of Covid-19 include fever, dry cough, and difficulty in breathing but Muscle pain, sputum production, diarrhea, and sore throat are less common(Singhal 2020)(Centre for Disease control and Prevention, 2020). Although most of the result cases are mild, and some of them do not feel that he or she infected with the virus, in the progress, some symptoms such as pneumonia and congestion of some organs of the body have been reported. In the month of March 2020, with the considering age levels and other health issues, the average rate of death per number of diagnosed cases in March 2020 was 4.4 percent; however, it ranges from 0.2 percent to 15 percent (Li et al ,2020). And also have been reported in the gulf states. Since the beginning of the spread of the disease from Wuhan, a city in the Hubei Province of China, which dates back to December 2019, a very high rate has been announced, which more than 80,000 of COVID-19 cases have been reported in China. With the majority of those from Hubei and surrounding provinces (WHO ). China fact-finding mission estimated that the epidemic in China had reached its peak of spread between late January and early February 2020 (WHO Media Report, 2020. In early March, the number of cases in China dropped dramatically, however, at that time cases have been reported in all continents with the exception of the southern hemisphere, After a while in some parts of the world the rate of infection and death is rapidly increasing. After a while the rate of infection and death because of the COVID-19 has risen sharply, in the United States of America and many other Western European countries include united kingdom more cases have been reported and the disease have reached Southeast Asia, with more cases being registered daily in a country like Iran. and this has forced the countries to announce sudden lockdown(Wu, Leung et al. 2020).
The virus is typically transmitted via respiratory droplets produced through coughing and sneezing as well as through contact with contaminated objects or touching the face of an infected person (Centers for Disease control and Prevention, 2020). Some studies have suggested that the virus may remain on different surfaces for 72 hours (National Institutes of Health, 2020).
The period between exposure and onset of the disease lasts from two days to 14 days, with a an average of 5 days (Centers for Disease control and Prevention, 2020 Zhou et al, 2020). The standard method of diagnosis is by reverse transcription polymerase chain reaction (RT-PCR) from a nasopharyngeal swab. The infection can also be diagnosed from a combination of symptoms, risk factors and a chest CT scan showing features of pneumonia (Jin YH et al, 2020).
On February 19, 2020, 2 person in the Qum region of Iran was admitted with an atypical pneumonia that later proved to be COVID-19. In the next few days around the country were 245 more cases. This was the beginning of one of the largest and most serious clusters of COVID-19 in the Gulf states (WHO, 2020). Despite aggressive effort, the disease continues to spread and the number of affected patients is rising in Iran and it has also becomes higher than that of China. Iran has recorded higher number of cases per day and new deaths per day.
Untill the preparation of this research 7 July 2020, as illustrated by a chart from the (Figure 4) the coronavirus COVID-19 has affected 215 countries and territories around the world with a total 11,749,001 cases, resulting in over 540,860 deaths but more than 6,742,622 people have recovered from this deadly virus (Worldometer, 2020).