Coronaviruses are major viruses that cause a variety of diseases in many animals and humans, and have long been known to cause colds in humans. With the start of Covid-19 in China and its dissemination to the continents of the world, the World Health Organization declared Covid-19 a pandemic (1). The incidence of this disease in Iran has similarly affected people and has vastly increased the number of referrals to the hospitals, with subsequent increase in the number of hospitalizations in the provinces involved. Considering the occurrence of the disease in China in late December 2019, thoughtful and detailed planning was taken in advance at Zanjan University of Medical Sciences and the Deputy of Health, to get fully prepared for the management of the outbreak in the province. Among the measures taken at the level of health care, was thoughtful and meticulous planning  to get prepared for the control of the outbreak  including preparation of  training packages for diverse groups of people such as the requires trainings for the control and prevention of Corona Virus, preparing training and disease prevention platforms, as well as monitoring and screening foreign workers in the province, introduction  of selected centers for timely referral of patients, closure of all universities and schools, and continuous disinfecting of public transport vehicles and disinfecting 52 areas of the province, determination of quarantine stations for suspects and patients, provincial ban on all gatherings, hookah houses, restaurants, halls, ceremonies, continuous monitoring of all business activities and bakeries, etc.
With the pandemic of Covid-19 and its country-wide dissemination, given that about 85% of cases of Covid-19 indicate mild or asymptomatic symptoms; identifying and isolating Covid-19 patients sound incredibly efficient in reducing R0 rate and consequently preventing and controlling the incidence. To this end, an innovative planning was implemented in Zanjan province since March 26, 2020 to screen the cases of Covid-19 in outpatients referred to 16-hour centers.

 

Kidney function was evaluated by measuring the kid- Zanjan province has 8 cities, the demographic charac-teristics of which are as follows:(Table 1).

Table 1. Demographic characteristics of Zanjan province

A: General information on the status of care and treatment of suspected cases of Covid-19 in the 16-hour outpatient centers of the province:
 

As the table 2 shows the frequency of females and males who referred to outpatient centers was 16255 and 15682, respectively.

Table2. The total number of clients who referred to the selected comprehensive health service centers by May 16, 2020

The number of positive cases with suspected Covid-19 and people in contact with these patients, in the 16-hour centers of the province is 10056.  The total number of tested samples is 9760 (Table 3). The total number of detected positive cases was 1917 (19.6%).
The percentage of positive samples to the total number of tested samples obtained from outpatient centers by cities is as follows: Abhar 19%, Ijroud 12%, Khodabandeh 23%, Khorramdareh 18%, Zanjan 22%, Soltanieh 21%, Tarom 14%, Mahneshan is 19%, and ultimately across the whole province, this value is 20% (Table 3).

Table3. The status of Covid-19 incidence in the cities of Zanjan province

It seems that the samples correspond to the population of each city, i.e., by comparing the population of Abhar and Mahneshan, in proportion to the population of Abhar which is 4 times more than Mahneshan, the size of samples correspondingly increases. The city of Zanjan has a population of 3 times more than Abhar and the size of sample is subsequently larger. Therefore, comparing the size of samples with the population of cities, the obtained sample sizes are reasonably reliable.
The Covid-19 age specificity in our 16-hour outpatient centers (per 100,000 population) had the following distributions: age range under 10 years old:  47 cases; 10 - 19 years old : 111 cases; 20 - 29 years old: 169 cases; 30 - 39 years old:227 cases; 40 - 49 years old:  229 cases; 50 -59 years old:  247 cases; 60 - 69 years old:  270 cases; 70 - 79 years old : 336 cases;  and finally over 80 years old  had 237 cases.
As the table 4 shows, outpatient total cases exceeded hospitalized patients. In Abhar, for example, there were 177 outpatient cases and 83 hospitalizations, i.e., significantly double in value. In Ijroud and Soltanieh, the number of hospitalizations is noticeably lower indicating that the disease detection is more accurate and therefore the hospitalization figure in these two cities tends to be lower.
Outpatient case detection brought about a marked effect on reducing hospitalized cases; otherwise, we would have faced a significant peak in hospitalization and subsequent increase in mortality rates.

Table 4. The incidence of Covid-19 disease in 16-hour outpatient centers of the province by May 16, 2020 in terms of cities

 
Figure1. Distribution map of inpatient cases of Covid-19 in city of Zanjan (incidence per 100000 people).
 
 
Figure2. Distribution map of outpatient cases of Covid-19 in city of Zanjan (incidence per 100000 people).

Discussion

The Covid-19 pandemic is currently the world's most important health challenge. The rapid and dramatic dissemination of Covid-19 has given rise serious social, economic, cultural, psychological and even political issues in the countries. Although, this virus seems to have a lower death risk in comparison with other emerging viruses in the Corona Group, such as Sars and Mers, the rate of incidence and pathogenic behavior of this virus make it extremely difficult to control (2).
The pandemic caused by the spread of the virus, has led countries to adopt policies that are tailored to their circumstances. Due to the lack of treatment methods, vaccines, and the rate of contagiousness and pathogenicity, sufficient efforts must be taken to slow down the progression of this disease and assure safety in the community, to alleviate intense pressure on the health system, and to provide sufficient opportunities for the development of effective treatment and prevention methods (3). To achieve this goal and delay the onset of the disease, the most effective tool available at the moment is to isolate patients, so that suspicious and infected people have the least contact with healthy people and thus break the transmission chain (1, 3).
Accordingly, it seems that this epidemic is very serious and requires long-term measures. To control the first wave of the outbreak, the policy of isolating suspicious patients and reducing close contact with infected people is the most important factor for controlling the disease. The first step in achieving this, is to perform timely and rapid screening of suspected individuals in laboratory (4-9). Therefore, an innova-tive screening plan was proposed to fight against Covid-19 and cut its chain and reduce R0 and generational renewal (10-12). Ultimately, the practical purpose of this project implementation was to reduce disease transmission and cut off transmission chain. Screening based on salamat.gov.ir system is continu-ously carried out successfully in the province and due to the one-on-one screening of patients, we have been able to diagnose and screen about 80% of patients within three days of the onset of symptoms, and another 20% within 6 days.
In health science and epidemiology of infectious diseases, one of the most important indicators that can help health policymakers’ prediction of the future epidemics is R0 index. The R0 index reached 1.4 in the province following the implementation of the Covid-19 Outpatient Laboratory Screening Project.  This value fell below 1, indicating that the best way to control the disease is to find positive cases and have control over them.
Considering that covid-19 disease is an easy-to-transmit respiratory disease, and given that in the normal course of transmission of this disease, up to 85% of cases may be asymptomatic or mild; merely following-up, monitoring and care of hospitalized cases (15%) seem like the tip of the iceberg and inadequate; which may greatly surprise the health system admitting that a vast majority of asymptomatic patients (85%) act as carriers of the disease and  infect people who are more susceptible to the disease, and disseminate the infection and transmission chain all over the  society (1,2, 13-15). Therefore, in order to screen, detect, care and examine people in contact with Covid-19 patients with the goal of their isolation and implementation of environmental measures on one hand and relying upon the research proposal of Zanjan University of Medical Sciences and subsequent approval of the Ministry of Health and Medical Education, the laboratory outpatient screening project was implemented in patients referred to 16-hour and 24-hour outpatient centers. The analysis of the results of this study project in Zanjan province is as follows:
The total number of clients and those referred to the comprehensive selected health care centers by May 16, 2020, was 31,937, of whom 48% were men and 52% were women. The highest percentage of patients identified in the tested cases prior to the date of writing this article incorporates to Zanjan and Khodabandeh cities. However, 20% of the tested samples comprised positive cases of Covid-19 in the province. Based on the results of our study, the incidence is seen in all age groups. Due to the population of different age groups and the process of adaptation with specific population, the highest specific age incidence of covid-19 in outpatient centers of the province related to the age group over 70 years. A significant point in the specific incidence of age-related outpatient cases compared to hospitalized cases is the substantial distribution of all age groups, so that in a comparison of inpatient with outpatient cases, the proportion of age groups under 60 years old was considerably low.
On the other hand, we came to the conclusion that isolation at home alone does not provide favorable conditions and is not considered fairly valuable. According to our investigation, 36.8% of those with positive Covid-19 test who were in a home-based quarantine, indicated that they did not receive effective isolation care at home.
The Covid-19 detection process is increasing in outpatient cases since the implementation of screening project was implemented. This increase is interesting compared to the decrease in hospitalized cases. The reason for this proportion may lie in the fact that before the implementation of the Covid-19 Screening Project, a large number of cases of Covid-19 (85%) lacked clinical signs or had mild clinical symptoms and easily disseminated the disease in the community. i.e., they were not tested and no identification or isolation was carried out. Therefore, following the implementation of the screening project and the referral of suspicious outpatient cases and those around them to 16-hour centers and their identification, treatment, care, isolation and control, the number of visits to the province's hospitals decreased. In other words, of 1,833 positive cases identified so far, merely 65 have been hospitalized.
The incidence of covid-19 among outpatient cases in Khorramdareh and Soltanieh cities was higher than other cities of the province. Interestingly, the disease is less common in some cities, where positive cases of covid-19 have been identified which may be due to the lack of proper facilities in the mentioned cities, which has led to more severe cases being referred to more specialized hospitals. This notion means that throu-ghout screening and detecting the outpatient cases, extreme care is required in detecting more patients. This issue includes a significant number of patients and has played an effective role in the rotation of the virus in the mentioned cities. However, by treating outpatients, we reduced hospitalizations. The number of people who discharged from outpatient hospitals also decreased, and we did not have even a single case of death. It is hoped that in the future the disease will be controlled in these cities, with timely identification and home isolation or referral to a recovery center. The distribution map of outpatient and inpatient cases in Zanjan city has also been examined. The noteworthy point is the high incidence of Covid-19 in areas with higher social and economic status, which is probably due to the unwillingness of people to refer to such public centers. The higher the income level, the more hospitalized cases, which displays that the private sector is not able to take optimal measures to prevent and diagnose the disease on its own. In areas with lower incomes, the rate of outpatient disease is vast, while the rate of hospitalization is less, indicating the ability of comprehensive health care centers to diagnose and take health measurements.
Outpatient laboratory screening measures have significantly reduced the number of hospitalizations in the province. In a way that, for example, in Abhar, Khodabandeh, and Zanjan cities out of 269, 206 and 973 positive cases, 83,49 and 123 cases were hospitalized, respectively. 46% of patients diagnosed in outpatient centers had clinical symptoms and 54% had no clinical symptoms.
87.5% of the cases identified in the outpatient centers of the province were isolated at home and 12.4% of the patients were monitored in the recovery centers of the province. Considering that it is difficult to monitor patients isolated in homes due to the lack of legal procedures, setting up recovery centers and conse-quently isolation of patients in these centers can be an effective way to cut the Covid-19 transmission chain.
Out of the followed-up and contact tracing patients, 3936 cases with close contact were identified during this time span with an average of 2.1 contacts per person. Subsequent to contact tracing, 2,547 cases took laboratory tests, of whom 2,398 have received laboratory results so far and 149 are waiting to be reported. Taking into account the lab reports, 39.5% of the contact tracing samples have been identified positive.

Conclusion

The level of R0 in the province had reached to 1.4, which significantly dropped below 1 after the implementation of the covid-19 Outpatient Laboratory Screening Project. This result suggests that the best way to control the disease is to find and control the positive cases. 90.8% of the identified patients have been well isolated so far. On the one hand, the best way to control the disease is to find positive cases and control them. On the other hand, home-based isolation did not prove to be effective. This finding recommends that patients ought to be isolated and closely monitored in recovery homes and outdoor centers.

 

Acknowledgements

We are grateful to all the health defenders in all parts of Iran who attempt in the self-sacrifice of defending the health of their compatriots.

 

Conflicts of Interest

None.

 

Funding Sources

None.