Design and sample
Chinese scientists isolated a new Coronavirus (CoV) from patients in Wuhan, China, on January 7, 2020. The cause of the disease was a new Coronavirus called SARS-CoV-2, and the world health organization (WHO) named the common disease COVID-19, and declared the spread of SARS-CoV-2 as a state of emergency on January 30, 2020. The significant number of cases and spread of geographical spread of the disease posed a great threat to public health and attracted considerable attention worldwide, so that the World Health Organization declared that new coronavirus infection, COVID-19, as a pandemic (global epidemic) in March 2020. Despite the fact that the whole world has taken important steps to curb the spread of COVID-19.
The high rate of virus spread has caused countries to face large numbers of infected people. The current epidemic state of new coronavirus is still severe and worrying around the world, and efforts are making to slow its spread to save time to produce the appropriate vaccine or treatment[5, 6].
Until two decades ago, human coronaviruses were only known to cause uncomplicated respiratory infections such as cold, but two new coronaviruses, called SARS and MERS (In the years 2003 SARS and 2012 MERS), with higher disease severity, created severe epidemics around the world. Infection with Acute respiratory syndrome COVID-19 is very similar to other viral infections in terms of clinical manifestations[4, 8], and patients show a wide range of clinical symptoms from very mild and low symptomatic cases to very severe cases in which patients need intensive care and sometimes lead to death. Fever, cough, and fatigue is the main symptom of the disease at the beginning of COVID-19 infection, while it may be accompanied by other symptoms such as headache, hemoptysis (bloody sputum), diarrhea, shortness of breath sputum, and lymphopenia[9, 10].
In pulmonary CT scans, clear pneumonia is apparent; and RNA of virus can be detected in the blood. In severe cases, the clinical picture of acute shortness of breath syndrome can be observed, and it is associated with heart damage and pulmonary opacification, and usually leads to death. A high percentage of people (about 80%) in society show asymptomatic infection or mild symptoms of a cold[11, 12]. On average, about 20 percent of patients have more severe symptoms of the disease, including pneumonia, sepsis, septic shock, and acute respiratory distress syndrome that is associated with fluid accumulation in the lungs. Based on the severity of the disease, patients need to be assisted in breathing, and a small number of patients die (about 2% of cases that vary slightly in different studies)[3, 13].
The clinical symptoms of the disease begin after a period of almost 2.5 days, but the incubation period can take up to 14 days. The duration of disease onset until death is from 6 to 41 days and about 14 days on average in severe cases. Its duration depends on several factors, such as the patient's age and status of the immune system, so that the length of this period is shorter in patients over 70 years of age than patients under 70 years of age. People infected with COVID-19 can transmit it to healthy people even a few days before the onset of clinical symptoms[4, 11]. No specific vaccine or treatment has been offered for the disease yet. The number of cases is rapidly increasing in the current emergency status; hence, it is important to diagnose all suspected cases as soon as possible and isolate them quickly to cut off the infection source[9, 14].
COVID-19 is a new disease that can be transmitted from animals to human; however, there is insufficient knowledge about the new virus and its ways of transmission, zoonotic reservoirs, prevention methods, and its precise clinical manifestations are not entirely clear, and there is a need for further studies. It is necessary to have sufficient information about factors and determinants that are effective in causing its symptoms, complaints of the disease, and its consequences to properly manage this epidemic and take effective preventive and medical coping measures.
The present study was descriptive-analytical research in which all 1142 patients suspected of having coronavirus, who visited Saveh Medical Centers from February 9 to April 1 7, 2020, were included in the study. Inclusion criterion: all patients with coronavirus should have filed at the hospital. Exclusion criteria: the lack of cooperation and no informed consent to participate in the study. Data collection was performed using interviews, inserting information into the researcher-made questionnaires, and using the information in patients' medical records. To complete the questionnaires about hospitalized patients, the research team visited medical centers after obtaining the necessary permission from the university. In the case of outpatients and patients discharged from the hospital, they were contacted by phone, and then they made an appointment at their houses. After stating the research objectives and obtaining the patients' consent, the researchers interviewed the patients and collected data while maintaining confidentiality. Investigating and collecting the data from patients' files were also with permission from hospital authorities. In the present study, the definitive patients meant to have COVID-19 with positive results of the PCR. A suspected case was a patient with at least one of the following symptoms: dry cough, chills, sore throat, shortness of breath, and fever that were not justified with another etiologic agent. The negative case of the disease had a negative PCR result.
The data collection tool of the present study was a researcher-made questionnaire that was designed after reviewing authoritative scientific texts and consulting with experts in infectious diseases and epidemiology. The questionnaire consisted of socio-demographic information (such as age, occupation, gender, occupation, level of education, place of residence) symptoms and risk factors (such as underlying diseases, and history of substance abuse) of COVID-19. The content validity of the questionnaire was determined by both qualitative and quantitative methods. In the qualitative method, the questionnaire was given to 12 professors in the fields of infectious diseases, internal medicine, and epidemiology, and they were asked to examine the questionnaire in terms of using proper words, placement of items in the right places, and compliance with the grammar, and give the feedback. The Content Validity Ratio (CVR) and Content Validity Index (CVI) were calculated in examining the content validity by a quantitative method. To determine the CVR, the experts were asked about the necessity or non-necessity of each item; and values greater than 0.56 were accepted. To determine the CVI, the relevance, clarity, and simplicity of each item were reviewed, and values greater than 0.79 were accepted.
Data were analyzed by SPSS 21 using Chi-square, independent sample t tests, Fisher's Exact Test, and regression tests. Logistic regression was performed for determining the association between independent variables and death of covid-19. Only those independent variables that showed significant associations with death (P ≤ 0.05) in uni-variate analysis were included in the multivariate logistic regression models.
Permission to conduct the research was sought, and obtained from the Saveh Medical Centers. This research was approved by the Ethics Committee of Saveh University of Medical Sciences [IR.SAVEHUMS.REC.1399.002].