CLINICAL-EPIDEMIOLOGICAL PROFILE OF COVID-19 PATIENTS DURING THE FIRST WAVE OF THE DISEASE IN THE STATE OF PARÁ, BRAZIL

December 2019 saw several cases of pneumonia of unknown origin reported in Wuhan, China; the cause of this unknown disease was later identified as the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The purpose of the present study was to evaluate the epidemiological profile of coronavirus disease 2019 (COVID-19) in the North Region of Brazil to assess possible correlations between demographic, social and health factors as well as adherence to safety protocols and the epidemiological profile of COVID-19. Information was obtained via a socio epidemiological survey carried out using Google Forms shared on various social media platforms from May 13 to 20, 2020. 6,781 people, living in the State of Pará, participated in the study of which only 682 (10.1%) had been diagnosed with COVID-19. Of these, 43 (6.3%) required hospitalization. 155 (23.5%) tested positive by RT-PCR associated with computed tomography. The RT-PCR test, with no association with other methods, was performed in 77 (11.6%) cases and serology performed in 360 cases (54.6%). There was a higher prevalence of confirmed cases (457, 67.0%) in females than in males, and the predominant age group was 30 to 40 years of age (214 participants, 31.4%). Considering the relatively homogeneous demographic profile of the sample, continued research is vital, preferably multi- centric studies, to obtain relevant data regarding the epidemiological dynamics of COVID-19; this data will allow the development of pandemic-prevention strategies that consider the social, cultural and political aspects of specific locations.


INTRODUCTION
In December 2019, many cases of pneumonia of unknown etiology, spreading at an alarming rate, were reported to health authorities in Wuhan, China (Sun et al., 2020). Subsequently, researchers confirmed that the cause of the unknown disease was a new coronavirus, which is an RNA virus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the seventh member of the Betacoronavirus genus capable of infecting humans (Gorbalenya et al., 2020).
In January 2020, the World Health Organization (WHO) declared the SARS-CoV-2 outbreak a Public Health Emergency of International Interest (ESPII), and in March, it was declared a pandemic (Cucinotta & Vanelli, 2020; WHO, 2020a). The first case of coronavirus disease 2019  in Brazil was confirmed on February 26, 2020, and the presence of COVID-19 was first confirmed in the North Region of the country on March 13, 2020 Due to the rapid spread of COVID-19 in Brazil (Brazil 2020a, 2020b), clinical and epidemiological data were published daily on easily accessible media channels. Studies integrating epidemiological data from different geographic regions of Brazil are extremely important, especially since different regions are characterized by distinct and unique socio demographic characteristics. In this context, the present study describes the epidemiological scenario of COVID-19 in the state of Pará, northern Brazil, and evaluates possible associations with demographic, social, and health aspects, as well as adherence to safety protocols, to increase understanding of the pandemic in Pará during the first wave of SARS-CoV-2.

MATERIAL AND METHODS
In this cross-sectional descriptive study, a socio epidemiological survey with Google Forms was carried out using a convenience sample; the survey was shared on various social media platforms from May 13 to 20, 2020, and approved by the Research Ethics Committee of the Institute of Health Sciences (CAAE 31800720.1.1001.0018) of the Federal University of Pará. Only residents of the State of Pará who had a confirmed diagnosis of COVID-19 were selected. The socio-epidemiological characteristics were presented using descriptive statistics. Data were quantified and tabulated on Microsoft Excel version 2010 spreadsheets.

General characteristics of the participants
Between May 13 and 20, 2020, 6,781 residents in the State of Pará responded to the epidemiological survey. 4,690 (69.1%) participants resided in the capital city Belém (PA), and 982 (14.4%) resided in the municipality of Ananindeua (PA). Among the participants, 682 (10.1%) had tested positive to COVID-19.
Regarding education, 311 (45.6%) had completed postgraduate studies, and 154 (22.6%) were graduates. Regarding family income, 339 (49.7%) of the participants reported an income five times the minimum wage. Table 1 shows the general characteristics of participants in the survey that tested positive for COVID-19.
Regarding undiagnosed individuals, 4,279 (95.0%) said they had not been tested for COVID-19; while 218 (4.8%) claimed to have taken some test to diagnose the disease and nine (0.2%) did not inform. Regarding suspect cases of COVID-19, 1,040 (83.4%) individuals said they had not been tested, while 207 (16.6%) had undergone some test method.
Regarding the methods used for diagnosis, 155 (23.5%) reported being positive by RT-PCR associated with computed tomography. The RT-PCR test, with no association with other methods, was performed in 77 (11.7%) of the cases and serology performed in 360 cases (54.6%). Regarding the care of positive patients, 567 (83.1%) reported that they sought and received health care, and 115 (16.9%) reported not having access to health care. Forty-three (6.3%) people reported being hospitalized, while 639 (93.7%) reported that they had not required hospitalization.
Of the participants, 286 (42.0%) belonged to a high-risk group, while 396 (58.0%) did not belong to a high-risk group. Of the most cited risk factors, shown in Table 3, hypertension was predominant in 100 (35.0%) individuals, followed by respiratory disease in 65 (22.7%) and obesity in 59 (20.6%) people.
An important finding was that none of the 22 smokers (3.2%) who were positive for COVID-19 required hospitalization, while 42 nonsmokers (6.2%) were hospitalized.

Symptomatology
Regarding signs and symptoms from January 2020 until the time of questionnaire completion, 677 (99.3%) people reported symptoms during this period, 42 (6.2%) were hospitalized, and six (0.9%) were asymptomatic. Of those who had shortness of breath (331, 48.5%), 39 (11.8%) were hospitalized. The most prevalent signs and symptoms are shown in Table 4. 487 (71.4%) people reported contact with someone diagnosed with COVID-19, while 149 (21.8%) people did not know whether they had been in contact with someone diagnosed with COVID-19. Forty-six individuals (6.7%) reported no contact with people diagnosed with COVID-19. Table 5 shows that 612 (89.7%) people practiced social distancing. The supermarket and pharmacy were the most visited locations according to 489 (78.2%) and 448 (71.6%) individuals, respectively.
Among the 682 individuals diagnosed with COVID-19, only 112 (16.4%) did not have health insurance. Among those who had a health insurance plan, 36 (6.3%) were hospitalized, and among those without a private plan, 7 (6.2%) were hospitalized. In the first months of the new coronavirus pandemic, when this study was carried out, Brazil did not have the budget or venues to perform mass testing; therefore, the Ministry of Health advised that only those with moderate to severe clinical conditions should be tested. For patients with mild symptoms, self-isolation was recommended (Brazil, 2020a). This testing dynamic is reflected in the results of the present study, considering the relatively low percentage of people with a confirmed COVID-19 diagnosis and with serological testing the most frequent test method among participants. Bichara et al. (2021) noted similar results.

DISCUSSION
The WHO recommends RT-PCR molecular tests to detect the viral genome of SARS-CoV-2 in respiratory tract samples. RT-PCR is the gold standard for the diagnosis of COVID-19, and chest computed tomography is the best choice for image diagnosis in cases of severe acute respiratory syndrome associated with COVID-19 (WHO, 2020a). This may explain why for most of the participants, the diagnosis was confirmed by computed tomography and RT-PCR, as this was the recommended medical approach at the time. Bichara et al. (2021) reported similar results.
Regarding clinical factors, almost half of the interviewees reported belonging to a high-risk group, where hypertension, respiratory diseases and diabetes were the most reported comorbidities among the possibilities presented. This was similar to the results of other studies in the literature (CDC COVID-19, 2020; Richardson et al., 2020; Kreutz et al., 2020). Since the beginning of the pandemic, hypertension has been closely associated with the development of severe cases of COVID-19. This association may be related to the presence of the angiotensin 2 converting enzyme (ACE2). This enzyme, which is found in large quantities in patients with hypertension and diabetes, due to the use of drugs to control these diseases, is also considered the main point of virus entry into cells. In addition, ACE2 has been directly linked to organs such as the liver, heart and pancreas (Huang et al., 2020;Wan et al., 2020).
Among the signs and symptoms reported by the study participants, headache, cough, sore throat, loss of smell and taste, diarrhea and fever were the most frequently reported, similar to other studies (Silva et al., 2020; Giacomelli, 2020; WHO, 2020b; Bichara et al., 2021), even though there is a report classifying headache as a less frequent symptom (Zhu et al., 2020). Thus, it is worth noting that the referred signs and symptoms may vary according to the stage of the disease. Moreover, many people are considered asymptomatic, demonstrating that clinical characteristics, in many cases, are variable (Iser et al., 2020).
Regarding adherence to safety protocols during the COVID-19 epidemic, most participants reported practicing social distancing. Findings described by Bezerra et al. (2020) indicated that people who partially or totally isolated themselves believed that social distancing helped reduce the number of cases of COVID-19, preventing the spread of the virus by asymptomatic victims (Wilder-Smith & Freedman, 2020).
Although a large part of the studied population claimed to practice social distancing, a high percentage reported having had contact with people who had been diagnosed with COVID-19. This may be related to the fact that even among people who practiced social distancing, some daily activities, such as going to the supermarket or the pharmacy, led to contact with other people, which certainly favored exposure to the virus. Therefore, the recommendations for social distancing must always take into account the social, cultural and political characteristics of a particular population at the time of the pandemic (Aquino et al., 2020).
Most participants in this study claimed to use masks and practice hand hygiene, similar to the results of a study by Costa-Lima et al. (2020). Although some sectors of society question the effectiveness of wearing masks as a way of protecting against SARS-CoV-2, mask wearing is the WHO official recommendation and that of the Brazilian Ministry of Health. Further studies are necessary to demonstrate the effectiveness of this prevention method (Brazil, 2020b; Garcia, 2020).
The results of this study highlight that during the first epidemiological wave of the COVID-19 pandemic in Belém-PA, all safety protocols recommended by national and international health institutions regarding diagnosis, treatment, and prevention methods were generally reported as being followed. However, the social isolation index of 53%, as reported by the Government of the State of Pará in response to the confinement decree (lockdown) imposed on the population of Belém in April 2020, did not reach the expected minimum of 70%. This suggests that even though this population generally followed the guidelines for social isolation, daily life needs influenced adherence during the period that preceded data collection in this study, showing that if isolation recommendations are not conceived in compliance with the cultural and sociopolitical particularities of each location, the expected end result will not be achieved.
The fact that the study was carried out at the beginning of the pandemic period and that the questionnaire was applied online can be seen as factors that can influence the veracity of the responses obtained, since at the time of the research very little was known about the new coronaviruses and COVID-19. The lack of accurate information at the time on modes of transmission, prevention, diagnosis and treatment favored the proliferation of false news, with many questions arising every day. We understand that the complexity of the epidemic, together with the absence of precise information about the socioepidemiological aspects of COVID-19, may have influenced the investigated public's responses to the questionnaire, which can be considered a limitation in the present study.
Considering the relatively homogeneous demographic profile of this sample, it is important that further research be carried out, preferably multicentered studies, to obtain relevant data on the epidemiological dynamics of COVID-19 and, based on the information obtained, design more effective prevention strategies considering the social, cultural and political particularities of each location.