Epidemiological-Based Study of SARS-CoV-2 in Faisalabad

Simple Summary

The World Health Organization has declared the end of SARS-CoV-2 as a global health emergency. However, the disease remains a global threat, therefore it is important to understand the divergence of the epidemiology of SARS-CoV-2 in different populations. From a developing country like Pakistan, less data is available related to SARS-CoV-2 epidemiology. This study reports SARS-CoV-2 epidemiological data from Pakistan to highlight the patterns of infection. The study identified that SARS-CoV-2 was more prevalent in individuals who were middle-aged, male, and had low socio-economic status. The patients’ vaccination status highlights a critical gap in preventive healthcare and shows the need to strengthen vaccination awareness and accessibility in the population to reduce vulnerability to future outbreaks. This study has valuable practical implications for preventing the transmission of SARS-CoV-2 by guiding public health interventions.

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raced around the world across different populations; there needs to be a consolidated effort to understand the divergence of the epidemiology of SARS-CoV-2. Population-based epidemiological characteristics studies measure the extent of SARS-CoV-2 infection in a country. The current research study was designed to report epidemiological data from Pakistan. For this purpose, 246 SARS-CoV-2-infected patients were included in the study. For SARS-CoV-2 confirmation, viral samples were collected from all the study participants; SARS-CoV-2 infection was confirmed by viral nucleic acid detection using a nucleic acid detection kit. After SARS-CoV-2 confirmation, all the study participants were interviewed for epidemiological data through a detailed questionnaire. The study results showed that the disease ratio was higher between 30 and 59 years (51.21%) of age. The male ratio (55.28%) was higher compared to the female ratio (44.71%). The patients’ illiteracy and low socioeconomic status were 32.52% and 59.75%, respectively. The majority of the patients (97.56%) had cough, smell or taste disturbance (79.67%), or fever (76.42%), and 70.73% had fatigue. For comorbidities, a higher ratio was observed for diabetes (38.61%), hypertension (36.17%), and respiratory disease (16.26%). The vaccination status analysis revealed that 51.21% of patients had not received routine immunizations, and 65.5% were un-vaccinated against SARS-CoV-2. Notably, not a single patient was vaccinated for influenza vaccine. The current research study concluded that SARS-CoV-2 was more prevalent in individuals who were middle aged, male, and had low socio-economic status. The most common symptoms were cough, smell or taste disturbance, and fever. The patients’ vaccination status highlights a critical gap in preventive healthcare and shows the need to strengthen vaccination awareness and accessibility in the population to reduce vulnerability to future outbreaks. Future research should focus on investigating the impact of COVID-19 outcomes on comorbidities such as diabetes and hypertension.

1. Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 disease, which was initially reported in China on 30 December 2019. It is a novel infectious disease with devastating health implications and a range of manifestations from asymptomatic infection to severe pneumonia. Fast transmission and an asymptomatic incubation period make SARS-CoV-2 a lethal disease, which spreads through infected patients via respiratory droplets and the asymptomatic period (3–9 days) [1,2]. The SARS-CoV-2 infection’s initial symptoms include fever, cough, fatigue or myalgia, gastrointestinal symptoms, sputum production, dyspnea, loss of appetite, sore throat, chest pain or pressure, and taste or smell disturbance [3,4]. Clinical diagnosis includes physical examination, nucleic acid detection, CT scan, enzyme-linked immune-sorbent assay (ELISA) and IgM/IgG point-of-care testing (POCT) [5]. As of 16 February 2025, the World Health Organization (WHO) has reported 777.4 million confirmed cases, 7087,731 deaths (736 in the last seven days), and 13.64 bn doses of vaccines have been administrated [6].

SARS-CoV-2 belongs to the betacoronavirus family, having fast transmission and an asymptomatic incubation period that makes it a more lethal disease. The disease spreads through infected patients via respiratory droplets and the asymptomatic period (3–9 days) [1,7]. SARS-CoV-2 infections have a wide range of clinical characteristics that usually result in mild to moderate upper respiratory tract infections and a severe type of infection involving the respiratory, hepatic, gastrointestinal, and neurologic systems [8]. According to previous literature, seven coronavirus species have been identified that cause disease in humans [9]. These viruses are alpha-coronaviruses-229E, HCoV-NL63, beta-coronaviruses OC43, HCoV-HKU1, SARS-CoV, MERS-CoV, and SARS-CoV-2; in these, four prototypic coronaviruses cause endemic and epidemic respiratory infections such as alpha-coronaviruses-229E, beta-coronaviruses OC43, HCoV-NL63, and HCoV-HKU1 [10]. Among these viruses, HKU1, -OC43, -NL63, and HCoV-229E are distributed all over the world; they cause mild upper respiratory tract infections in adults, while they cause life-threatening bronchiolitis and pneumonia in infants, the elderly, and immunocompromised individuals [11,12]. Due to rapid mutation rate and genomic recombination, the disease becomes lethal. To date, several SARS-CoV-2 variants, such as Alpha (B.1.1.7 and Q lineages), Beta (B.1.351 and descendent lineages), Gamma (P.1 and descendent lineages), Delta (B.1.617.2 and descendant lineages), Epsilon (B.1.427 and B.1.429), Eta (B.1.525), Iota (B.1.526), Kappa (B.1.617.1), Omicron (B.1.1.529 and descendant lineages), Zeta (P.2), and Mu (B.1.621, B.1.621.1), have been identified [13]. These coronavirus (CoV) variants can have more serious outcomes in people and are responsible for CoV waves in different parts of the world [14].

SARS-CoV-2 caused respiratory manifestations; however, study evidence indicates that diseases have direct and indirect multiorgan effects, such as cancer and cardiovascular diseases, through change in healthcare delivery and patient behavior [15]. Many studies have reported that COVID-19 severity is associated with socio-demographical factors, obesity, and comorbidities [16]. In addition to poverty and overcrowded living environments, lower socioeconomic status is an essential component of catching COVID-19 disease. Being a developing country, Pakistan is the world’s fifth most populated country, where it is difficult to figure out the pandemic disease due to a smaller number of diagnosis tests and vaccine availability [17].

To gain more knowledge about COVID-19 asymptomatic and symptomatic cases, population-based epidemiological studies are the best way to know about potency and sustainability of acquired immune response from a public health perspective [18], because such individuals are often excluded from infection chain tracking and spread the disease silently [19]. Seroprevalence studies are important at a population level for tracking the pandemic evolution by enabling incidence estimates [20]. From a developing country like Pakistan, less data is available related to SARS-CoV-2 epidemiology. This study has valuable practical implications for controlling or preventing the transmission of COVID-19 by guiding public health interventions. With region-specific data, finding specific factors related to COVID-19 transmission and prevention would be useful for local health authorities to develop targeted and prevention-based strategies to mitigate viral transmission [21]. Regional epidemiological-based study findings can strengthen regional-specific preparedness and response-based frameworks that work best and are applicable to the circumstances. This study can contribute to understanding the regional dynamics of COVID-19 and help in making public health policies [22]. The current research study is based on a SARS-CoV-2 epidemiological-based study in Faisalabad Pakistan, studying the clinical, socioeconomic, and demographic aspects related to SARS-CoV-2.

2. Materials and Methods

2.1. Study Design

A cross-sectional study of SARS-CoV-2 patients was conducted at Allied Hospital Faisalabad, Pakistan. Allied Hospital ethical committee on human research approved the study protocol. Informed consent was obtained from all the study participants. Viral samples were collected from all the study participants, and epidemiological data was collected through detailed questionnaires with questions including the clinical, socioeconomic, and demographic aspects of the study participants. The sample size was determined based on estimated COVID-19 prevalence and logical feasibility.

2.2. Sample Collection

Viral samples were collected through nasopharyngeal swabs (FLOQSwabs^®, Copan Diagnostics, Murrieta, CA, USA) from all SARS-CoV-2 symptomatic patients. Viral nucleic acid detection was performed through a nucleic acid detection kit (QIAamp Viral RNA Mini Kit, QIAGEN, Venlo, Netherlands) (PCR florescent method), used according to the manufacturer’s instructions intended for in vitro qualitative detection of ORF1b (Open reading frame), N (Nucleocaspid), and E (Envelope) genes. SARS-CoV-2 nucleic acid was detected by monitoring fluorescent intensity RT-PCR (real-time polymerase chain reaction) (ABI7500 Instrument, Applied Biosystems, Foster City, USA) with internal control (Human RNase-P gene to ensure successful RNA extraction and PCR amplification, Thermo Scientific, Salt Lake, UT, USA) and external positive control (inactivated virus was used to validate the RNA extraction and PCR detection process, Thermo Scientific, Salt Lake, UT, USA).

2.3. SARS-CoV-2 Patients’ Epidemiological Data

SARS-CoV-2-infected patients’ epidemiological data was collected through designed questionnaires with questions that included age, gender, marital status, residence, occupation, body mass index (BMI), blood group, active smoking and passive smoking, education and socioeconomic level, number of individuals at home and at work, travel history, contact with COVID-19 patient, patient condition, nutritional status, infection before COVID-19, COVID-19 symptoms (fever, cough, gastrointestinal symptoms, myalgia or fatigue, sputum production, headache, dyspnea, loss of appetite, smell or taste disturbances, chest pain, and sore throat), comorbidities (diabetes, hypertension, CVD, respiratory disease, chronic liver disease, viral, and bacterial disease), and vaccination status (TB, measles, tetanus, poliomyelitis, diphtheria, pertussis, hepatitis B, pneumonia and meningitis, and seasonal influenza).

2.4. Statistical Analysis

The SARS-CoV-2 patients’ epidemiological data was analyzed using statistical software IBM^® SPSS^® software (Version 30).

3. Results and Discussion

According to the study results, the participants ranged from 13 to 86 years with the mean age of 46 years (SD 19.20). The COVID-19 infection ratio was found to be higher in the ranges of 30–39, 50–59, and 40–49 years with ratios of 18.69% (N = 46), 17.99% (N = 44), and 14.63% (N = 36), respectively, while other age groups, such as 20–29, 60–69, 10–19, 70–79, and 80–89 years, were 13.82% (N = 34), 12.19% (N = 30), 11.78 (N = 26), 10.56 (N = 26), and 1.62% (N = 4) (Figure 1). Adults are the most vulnerable individuals to get infected with COVID-19; they contribute to the highest proportion of the disease transmission. Nikolich et al. reported that in the UK, 17 million COVID-19 patients aged >60 years were at a high risk of hospital mortality, particularly those >80 years of age. Over the years the immune system of adults may undergo several changes, such as the production of B and T lymphocytes and coordination of the immune system that may lead to excessive immune response and further complications, including endotheliopathy and hypercoagulability [23]. Comorbidities are more common among older population, which is linked with poor outcome in COVID-19 patients. According to previous studies, older populations tend to have a higher risk of mortality associated with influenza and other respiratory viruses which are similar to those documented in SARS-CoV-2. COVID-19 cases in children show mild to moderate disease [24].

Among total 246 COVID-19-infected study participants, the male ratio was found to be higher compared with the female. The male and female ratios were 55.28% (N = 136) and 44.71% (N = 110), respectively, in which married and unmarried ratios were 83.73% (N = 206) and 16.26% (N = 40), respectively (

Table 1. Gender and marital status of the study participants.

Gender	Marital Status		Total Number
	Married	Unmarried
Male	116	20	136
Female	90	20	110

). According to results from recent research studies, males are more susceptible to COVID-19 infection than females. Our study results are also confirmed by various epidemiological-based studies from other countries. Alyami et al. reported that the COVID-19 infection rate was higher among adult males (median age between 34 and 59). COVID-19 severe cases were noted among adult patients (>60 years of age), particularly those suffering from comorbidities such as diabetes, cerebrovascular disease, and cardiovascular disease. Comorbidities weaken the immune system; for this reason, it is difficult for the weakened immune system to tackle the COVID-19 infection. Males more commonly have diabetes and cardiovascular disease (CVD); there is a high prevalence of smokers, and their lifestyle is different; that is why COVID-19 is more prevalent in males rather than females [24]. Another suggested risk factor that emerged from our study is that there is a gender difference in term of COVID-19 epidemiology, with males more susceptible to COVID-19 infection than females. Our study found that the highest proportion of COVID-19 cases was among the male population (on average 79% of the cases) compared to only 21% for females. Various epidemiological and population-based studies from other countries supported these findings. The incidence of COVID-19 was found to be the highest among adult males (median age between 34 and 59 years) [25,26,27].

The body mass index (BMI) of the study participants ranged from 15.9 to 34.1. The mean BMI was 23.24 (SD 4.25). According to the BMI data, the underweight (<18.5), normal (≥18.5), overweight (≥25), and obesity (≥30) ratios of the patients were 17.07% (N = 42), 43.15% (N = 116), 27.64% (N = 68), and 8.13% (N = 20), respectively (Figure 2). According to previous research studies, obesity is an important risk factor for the progression and death of hospitalized COVID-19 patients. The role of obesity and overweight in COVID-19 may relate to ventilation. Obesity is a risk factor for abnormal ventilation and can contribute to the overcoming of functional residual lung capacity and chest wall elastance. It is also possible that adiposity may have a direct role, i.e., via local biological effects of epicardial adipose tissue or other fat deposits in the body [24]. Malik et al. reported that due to prolonged viral shedding, the quarantine period for obese subjects should be longer than for normal-weight individuals [28].

The literacy rate of the study participants indicated that the ratio of illiterate individuals was 32.52% (N = 80); however, the educated individuals’ ratio was 67.47% (N = 166), in which the ratio of graduate individuals was 43.08% (N = 106) (Figure 3). According to the studies, that education plays a significantly important role in disease awareness. Educated individuals tend to have more awareness that is comparatively better than that of illiterate individuals, and they have better understanding of living in a healthy and clean environment [29]. Health literacy, including COVID-19 disease awareness, preventive behaviors, and compliance with pharmacological management, could thus be an important strategic intervention yielding long-term benefits [30].

The socioeconomic status of the study participants was found to be lower. The ratio of individuals with earnings per month of less than USD 99 was 59.75% (N = 147), while other groups, such as those with USD 100–199, 200–299, 300–399, 400–499, and >500, were 18.29% (N = 45), 1.62% (N = 4), 13.41% (N = 33), 4.47% (N = 11), and 2.43% (N = 6), respectively (Figure 4). Socioeconomic status was defined according to the Organization for Economic Co-operation and Development (OECD). The study results indicated that COVID-19 prevalence was more common in individuals with low socioeconomic status, particularly in developing countries. Individuals with higher socioeconomic status would have more resources to access health facilities and maintain healthier nutrition [31]. The results also indicated that study participants with balanced nutritional status had less severe disease status [29].

The COVID-19 symptoms of the study participants included fever, cough, myalgia or fatigue, sputum, headache, dyspnea, loss of appetite, smell or taste disturbance, chest pain, and sore throat; these were observed in the study participants. However, the majority of the patients had cough, smell or taste disturbance, fever, and fatigue, with ratios of 97.56% (N = 240), 79.67% (N = 196), 76.42% (N = 188), and 70.73% (N = 174), respectively. Other symptoms, such as loss of appetite, dyspnea, headache, chest pain, sore throat, and sputum production, were 60.97% (N = 150), 52.84% (N = 130), 39.02% (N = 96), 31.70% (N = 78), 31.70% (N = 78), and 30.89% (N = 76), respectively (Figure 5). According to the literature, that the onset of COVID-19 infection fever, cough, and fatigue are the most common symptoms. However, individuals with mild COVID-19 might experience sputum production, sore throat, diarrhea, joint pain, headache, and disturbance of taste and smell [32]. The COVID-19 disease spectrum ranges from asymptomatic to mild upper respiratory illness, to moderate to severe disease with respiratory compromise, to acute respiratory distress syndrome and organ failure, to death [33]. COVID-19 infection symptoms appear after a virus incubation period that depends upon the patient’s age and immune system status [34].

The study participants suffering from comorbidities such as diabetes, hypertension, CVD, respiratory disease, chronic liver disease, TB, HBV, and HCV were noted, where high ratios of diabetes, hypertension, and respiratory disease were observed with ratios of 38.61% (N = 95), 36.17% (N = 89), and 16.26% (N = 40), respectively. Other diseases, such as chronic liver disease, CVD, TB, HBV, and HCV, were 10.56% (N = 26), 8.94% (N = 22), 4.87% (N = 12), 1.62% (N = 4), and 1.21% (N = 3) (Figure 6). According to recent studies, diabetes has been identified as an important risk factor for the rate of progression to acute respiratory distress syndrome (ARDS) and mortality in hospitalized COVID-19 patients [35]. Early reports from Wuhan, China, and Italy reported a high prevalence of diabetes among severe cases of COVID-19 [24]. Wang et al. reported that diabetes, hypertension, cerebrovascular disease, and cardiovascular disease are major risk factors for COVID-19 patients. For clinicians, knowledge of these risk factors can be a resource in early appropriate medical management of COVID-19 patients [36]. COVID-19 patients with comorbidities lead to a severe infection cycle due to a weak immune system and chronic inflammation and are substantially associated with significant mortality; that is why comorbid patients must adopt vigilant preventive measures and require scrupulous management [37].

The study participants’ vaccination status, particularly the WHO-recommended routine immunization vaccines, such as TB, measles, tetanus, polio, pertussis, diphtheria, hepatitis B, pneumonia, meningitis, seasonal influenza, and SARS-CoV-2, were observed, where none of the patients were vaccinated with seasonal influenza vaccine; it is common in Pakistan that people do not get the vaccine doses for seasonal influenza and rely on the natural course of treatment each season [38]. However, the vaccination ratio of other vaccines, such as TB, measles, tetanus, polio, pertussis, diphtheria, hepatitis B, pneumonia, and meningitis, was 51.21% (N = 126), and not vaccinated was 48.78% (N = 120) for all, respectively, and 34.5% (N = 85) were SARS-CoV-2 vaccinated while 65.5% (N = 161) were not (Figure 7). Despite the increases in routine vaccination coverage during the past three decades in developing countries, the targets of completing the recommended vaccination schedule remain below expected targets, particularly in adult individuals who remain unvaccinated during childhood. As a current study showed, more than half of study participants were unvaccinated [39]. The reasons associated with unvaccinated individuals were related to geographic barriers, disturbances in receipt of immunization services, missed opportunities to vaccinate, and limitations in immunization-related communication and information regarding vaccination. It is noted that low education level, low socioeconomic status, and religious backgrounds were occasionally correlated with low vaccine uptake, particularly in Pakistan, Nigeria, and India [5].

Socioeconomic status and literacy rate have a correlation with living standards, access to healthcare, and education [40]. In this study, 59.75% of the study participants have less than USD 99 per month, which shows financial challenges to accessing healthcare and maintaining hygiene that ultimately increased the risk of diseases such as hypertension and diabetes. An additional factor was literacy rate; 32.52% of the study participants were illiterate, which indicates less awareness related to health and safety information, especially prevention of viral transmission; that is why all the participants were unvaccinated against seasonal influenza [41].

The outcomes of this cross-sectional study of SARS-CoV-2 patients share similarities with previous studies showing that middle-aged males are more prone to infection and comorbidities, such as diabetes and hypertension, which make the infection condition worse [42]. However, this study identifies a high rate of illiteracy, low income, and absence of seasonal influenza vaccination, which indicated a reflection of limited resources, health literacy, and barriers accessing health facilities. This study recommends that authorities organize events at the community level, where they can raise awareness in local languages about health safety and disease prevention and the importance of vaccination.

4. Conclusions

The current study highlighted key demographic and health-related factors associated with SARS-CoV-2 infection. The age group most affected by COVID-19 ranged from 30 to 59 years, with a higher infection rate observed in males compared to females. Illiterate and low-socioeconomic individuals were more prone to disease. The most common symptoms were cough, smell or taste disturbance, fever, and fatigue, with a notable prevalence of comorbidities, such as diabetes, respiratory diseases, and hypertension. Unfortunately, not a single patient was vaccinated with the influenza vaccine. These findings emphasize the importance of addressing underlying health conditions, improving socioeconomic status, and promoting vaccination to mitigate the impact of COVID-19. This molecular epidemiological study may encourage SARS-CoV-2 national policy formulation to trigger the control of viral transmission and urge people to vaccinate. The head of the United Nations WHO has declared “with great hope” an end to COVID-19 as a public health emergency, stressing that it does not mean the disease is no longer a global threat.