Factors associated with COVID-19 deaths in Sierra Leone, March 2020 - March 2022

Stephen Lawrence Musa Kamara^1,2, Adel Hussein Elduma^1,2, Umaru Sesay^1,2, Binta Bah^1,2, Joel Francis Mansaray^1,2, Magoba Bridget³, James Sylvester Squire^1,2, Amara Alhaji Sheriff^1,2,4, Solomon Aiah Sogbeh^1,2,4, Gebrekrstos Negash Gebru^4,3,&

 

¹National Surveillance Program, National Public Health Agency, Freetown, Sierra Leone, ²National Surveillance Program, Ministry of Health, Freetown, Sierra Leone, ³African Field Epidemiology Network, Sierra Leone, Freetown, Sierra Leone, ⁴Sierra Leone Field Epidemiology Training Program, Freetown, Sierra Leone

 

 

^&Corresponding author
Gebrekrstos Negash Gebru, Sierra Leone Field Epidemiology Training Program, Freetown, Sierra Leone.

 

 

 

 

The novel Coronavirus Disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus type two (SARS COV2), is a global pandemic that negatively affected population health, social interaction, and the economy [1,2]. The primary determinants of COVID-19 transmission are socio-ecological factors, such as population density, age, hygiene, and poor air quality [3]. According to the Centers for Disease Prevention and Control, persistent and multiple underlying medical conditions, diabetes with complications, obesity, anxiety, and fear-related disorders are factors that exacerbate COVID-19 deaths [4].

 

Globally, COVID-19 has affected more than 776 million people and caused 7 million deaths by the end of September 2024 [5]. The Western Pacific region accounted for the highest burden of COVID-19 cases, with 208,572,684, and the Americas with the highest number of deaths, with 3,035,072. However, Africa reported the lowest burden of COVID-19 cases and deaths (9,583,532 and 175,531 respectively) [5], this could partly be due to the younger population (60% less than 25 years old), travel restrictions, and low foreign travel [6-9]. Given the numerous challenges, these statistics may be suboptimal, including limited funding, weak surveillance systems, limited logistics, and low COVID-19 vaccination coverage [9]. Even though COVID-19 infection rates were low in Africa, the pandemic exacerbated the double burden of diseases and increased disparities in access to and use of healthcare services. It disrupted agriculture, production, mining, and trade [10]. In low-resource countries such as Sierra Leone, the effects of the pandemic may be even worse, due to the recent Ebola outbreak (2014 and 2015) [11] causing 14,000 cases and nearly 4000 deaths [12]. Following the first COVID-19 case detection in Wuhan, China, the World Health Organization (WHO) declared it a public health emergency of international concern on January 30, 2020. It recommended member states to document and report all cases and deaths to the global COVID-19 clinical data platform [13]. This is to improve understanding of the natural history of the disease, prognostic factors, clinical features, and outcomes [13]. In response, the government of Sierra Leone declared COVID-19 as a national public health emergency on 24 March 2020 [14]. Followed by a ban on international travel to countries with high transmission rates, training clinicians to heighten the index of suspicion, and social distancing to at least one meter [15]. Despite implementing these measures, Sierra Leone detected its first COVID-19 case on 31 March 2020 [16]. From March 2020- October 2021, a total of 249,534 samples were tested using PCR of which 6,398 confirmed positive (average positivity rate of 2.56%) and 121 deaths reported. During the pandemic, the country experienced three waves (week 15, 2020 -week 43 ,2021) in which all deaths occurred during the peak of the waves [1].

 

Studies have reported older age (≥70 years and above), comorbidities, unemployment, and a high number of tourists as drivers of COVID-19 deaths [17,18] whereas human mobility and host susceptibility as drivers of COVID-19 infection in Africa [20]. In Sierra Leone, although studies have been conducted on COVID-19 cases and its impacts [1,20,21], only two studies have examined factors associated with COVID-19 deaths [22,23]. Botu and colleagues reported an altered level of consciousness, high levels of neutrophils, and C-reactive proteins as factors associated with COVID-19 deaths in Sierra Leone [22] while Olivia et al showed that hypertension is an associated factor to Covid -19 deaths [23]. Although the studies provided information on factors associated with COVID-19 deaths in Sierra Leone, both utilize data from a single health facility and as a result, the findings may not apply to all COVID-19 cases and deaths reported in Sierra Leone. Understanding the scope, severity, and factors associated with COVID-19 cases and deaths is crucial for informing future public health and clinical interventions and policies in preventing the spread of large-scale pandemics. This study aimed to examine the associations of sociodemographic and clinical characteristics that influenced the outcome of COVID-19 deaths in Sierra Leone.

 

 

Study design and period

 

We conducted an analytic cross-sectional study from September 2023 to February 2024 on COVID-19 cases and deaths.

 

Study area

 

This study was conducted in Sierra Leone. Sierra Leone is located on the west coast of Africa, bordering Liberia in the southeast and Guinea in the northeast. According to the mid-term population census, Sierra Leone has an estimated population of 8.5 million [24]. The country has five regions with 16 districts and 1,328 health facilities, each with a COVID-19 diagnostic and treatment facility. The National COVID-19 Emergency Response Centre (NACOVERC) manages COVID-19 cases and fatalities [25] which is also known as District COVID-19 Emergency and Response Center (DICOVERC) at the district level. . The stakeholders in this organisation are representatives from the Ministry of Health, Ministry of Defense, and Ministry of Finance.

 

All COVID-19 probable cases, confirmed cases, and deaths were included in the study.

 

Study population

 

Individuals who were laboratory confirmed for COVID-19 infection with Severe Acute Respiratory Syndrome type two (SARS-CoV-2) based on nasopharyngeal swabs and met diagnostic criteria by WHO [26] and recorded in the district health information system (DHIS 2) were included in the study [27]. Also, individuals who were epidemiologically linked (probable case) to a confirmed case were included in the study. Covid 19 deaths were deaths of laboratory confirmed Covid-19 cases or death not otherwise explained in an adult with respiratory distress preceding death and who was a contact of a probable or confirmed case or linked to a Covid -19 cluster [26].

 

Data extraction

 

We extracted data from the eCBDS platform in the DHIS2, from March 31, 2022, to April 14, 2022. All COVID-19 confirmed cases and deaths reported from March 31, 2020, to March 31, 2022, were included in the extracted data. We categorized outcome variables based on the patient's final vital status (dead or alive). The independent variables included socio-demographic factors (age, sex, and location) and clinical features (including fever, diabetes, and hypertension).

 

Data cleaning and management

 

The extracted data was cleaned by removing patient records with missing variables. Personally identifiable information of patients such as name, address, and facility names were removed. The raw dataset was stored in a Microsoft excel version 2019 with access granted only to authors who participated in the data analysis and visualization.

 

Data analysis

 

We used univariate analysis to identify important variables based on the literature to build the logistic model. We computed bivariate and multivariate analysis in Epi-info software version 7.2.5 (16) using 0.2 as a cut-off point to select variables from the bivariate analysis to be included in the multivariable model. To control for confounders, we used multivariate analysis to compute the adjusted Odd Ratio (aOR) at 95% CI to identify factors associated with COVID-19-related deaths.

 

Data validation

 

We explored the global clinical database platform developed by WHO to validate our study findings [13] and a partial validation using study findings reported in a retrospective study conducted among 180 COVID-19 patients at the 34 Military Hospital in Freetown, Sierra Leone [22]. However, since our study focuses on both confirmed and probable cases, neither database was used in this investigation. This is because only confirmed cases were uploaded to both systems. The results of the study are comparable to a study on COVID-19 deaths among patients admitted to the 34 military hospitals in terms of the factors linked to these deaths.

 

Ethical consideration

 

Taking into consideration that the study was a secondary data analysis of existing COVID 19 data in the DHIS 2, and routine data analysis is carried out as part of the mandate of the surveillance unit of the ministry of health to conduct surveillance activities. We obtained permission from the Ministry of Health (MoH) through the National Disease Surveillance Program at the Directorate of Health Security and Emergencies (DHSE) to use the data for the study. Personal identifying information were excluded to protect cases and extracted data was kept on a password-protected computer.

 

 

A total of 8,595 COVID-19 cases and 276 deaths (CFR 3.2%) were recorded for the period under review. Among these cases, 88%(7571) were less than 60 years of age, 57.8% (4969) were males, 3.2% (277) were healthcare workers and 73.7% (6335) were residents of Western Area Urban (Table 1). Of the total deaths, the median age was 60 years (IQR: 46 - 70.3), and males accounted for 62% (171/276). The age group 60 years and above accounted for the highest number of deaths with 55% (153/276). Healthcare workers accounted for 3.6% (10/276) of the total deaths. Moreover, the Western Area region (52.2%-Western Area Urban and 8.3%-Western Area Rural) had the highest proportion of COVID-19 deaths, followed by Kenema District, 12.7% (35/276). Falaba District recorded no deaths. The proportion of deaths reported from the community was 49% (134/276), while 51% (142/276) were reported from the health facilities. Bombali District had the highest case fatality rate of 26.4 % (18/68 followed by Kenema District, 26.3% (35/133). Regarding clinical signs and symptoms, 39.5% (109/276) cases never presented any signs before their deaths. Fever accounted for the highest with 46% (126/276), followed by those having difficulty of breathing, 37% (101/276), cough, 34% (94/276) and malaise, 27% (75/276) (Table 2), whereas 86% (7152/8319) of those alive never presented with any signs/Symptoms of COVID -19. In addition, Hypertension was the leading co-morbidity among COVID-19 deaths with 17% (47/276), followed by diabetes with 10% (28/276) (Table 3).

 

At the bivariable level, the following variables were statistically significant: Demographic characteristics- aged 60 years and above (OR= 11.4, CI: 8.9 - 14.6), reside in other regions outside Freetown (cOR= 3.3, CI: 2.6 - 4.3), Referred by Community alert/signals (cOR= 0.4, CI: 0.3 - 0.5); Signs and Symptoms: Fever (cOR= 6.9, CI: 5.4 - 8.9), Sore Throat (cOR= 2.6, CI: 1.5 - 4.6), Unconsciousness (cOR= 126.0, CI: 35.3 - 449.1), Cough (cOR= 5.3, CI: 4.1 - 6.9), Difficulty Breathing (cOR= 14.6, CI: 11.1 - 19.0), Weakness (cOR= 6.2, CI: 4.7 - 8.2), Underlying conditions/Co-infections: Cardiac Disease (cOR= 14.0, CI: 7.0 - 27.9), Diabetes (cOR= 14.3, CI: 9.0 - 22.7), HIV infection (cOR= 7.2, CI: 2.4 - 24.5), Hypertension (cOR= 10.6, CI: 7.5 - 15.1), Diabetes and Hypertension (cOR= 19.8, CI: 10.2 - 38.3).

 

At multiple logistic regression level, COVID-19 death was ten times more likely among patients aged 60 years and above as compared to those below 60 years old, and was statistically significant (aOR= 10.0, CI: 7.0 - 13.1). Patients with fever and those with difficulty in breathing were independently associated with COVID-19 deaths (aOR= 2.2, CI: 1.5 - 3.2) and (aOR= 4.2, CI: 2.9 - 6.1), respectively. COVID-19 deaths among patients in coma were 11 times higher compared to patients not in coma (aOR= 10.8, CI: 2.2 - 52.2). Also, HIV/AIDS patients who were infected with COVID-19 were four times more likely to die compared to patients without the disease (aOR= 4.4, CI: 1.3 - 14.8). Furthermore, diabetes, hypertension, and diabetes-hypertension combined coinfections were independently associated with COVID-19 death, with (aOR= 2.4, CI: 1.1 - 5.1), (aOR=2.8, CI: 1.6 - 4.8), (aOR=2.5, CI: 1.1 - 5.8), respectively (Table 4).

 

 

This study, which aims to assess the factors associated with COVID-19 deaths in Sierra Leone, highlights several critical insights. The CFR of COVID-19 in Sierra Leone (3.2%) was slightly lower than the global estimate of 3.64% but slightly higher than the African region estimate of 2.95% by the end of March 2023 [28]. This suggests that while Sierra Leone did better than the global average, it still experienced higher mortality than the regional average. On the other hand, the low COVID-19 deaths in our study could be attributed to the prompt implementation of COVID-19 prevention and control measures through the robust surveillance system established for COVID-19. The lessons learned from the 2015 recovery plan aimed at rebuilding the Ebola outbreak response, particularly preparing for and responding to outbreaks, [30] may have contributed to the reduced deaths in Sierra Leone. This explanation was reported in a similar study conducted in Sierra Leone [22]. As anticipated, the Western Area urban recorded the highest number of COVID-19 deaths while Falaba District recorded no deaths. The Western Area Urban, which hosts the majority (15%) of the Sierra Leone population, [31] recorded the first COVID-19 case in Sierra Leone in March 2020 [16]. In April 2020, the national COVID-19 response team in Western Area Urban mandated testing of corpses suspected of COVID-19, heightened COVID-19 surveillance, and trained clinicians on COVID-19 case detection and management. Implementing these measures could have potentially increased the magnitude of COVID-19 deaths in this district than in any other district in Sierra Leone. On the other hand, this study found Falaba District as the only district that did not record any deaths. To the authors' knowledge, there is no straightforward explanation to state why Falaba District did not record any deaths. This study, therefore, recommends a qualitative or mixed method to explore the reasons for no COVID-19 deaths in Falaba District and those districts with low COVID-19 deaths.

 

The study further revealed that older adults (aged 60 years and above) are more likely to die of COVID-19 infection than those below 60 years. These results highlight the critical impact of underlying health conditions on the severity and outcomes of COVID-19 infections. The increased mortality risk is likely due to a combination of weakened immune systems and the presence of comorbidities such as diabetes and hypertension, which are common in this age group [18,31]. This finding is consistent also with a systematic review study which indicated that older people with COVID-19 are more likely to die than young people [32]. Another study conducted by the US CDC reported that older adults aged 60 years and above had an 81% risk of dying from COVID-19 infection [33], which is similar to our study findings.

 

This study also found fever, difficulty in breathing, hypertension, Diabetes, cardiac disease, and HIV were clinical factors associated with COVID-19 deaths. This finding aligns with the study conducted by Anamika Gupta et al. on comorbidities and clinical complications associated with SARS-CoV-2 infection, where the authors reported multiple organ dysfunction and death among COVID-19 patients with pre-existing comorbidities [34]. This study recommends special attention and support be provided to individuals with existing medical conditions during public health emergencies to lower their risk of death.

 

Limitations

 

Three key limitations were identified in the study. First, this study could not account for COVID-19 deaths that were not reported in the DHIS2. This limitation may have resulted in an underestimation of certain findings. Secondly, due to the cross-sectional design of our study, we could not establish causality between variables. Thirdly, there was no significant data on vaccination in the DHIS2 at the time of this study. Studies have shown that COVID-19 vaccination protects people against COVID-19 infection [35,36]. A follow-up will still be conducted to assess the effect of vaccination on COVID-19. Despite this, our study provides comprehensive information on factors associated with COVID-19 deaths recorded in Sierra Leone.

 

Implication of study findings

 

Despite Sierra Leone's efforts to reduce disease severity during outbreaks, the relatively high CFR observed in this study shows the numerous challenges the country continues to face in treating and managing cases, especially those from emerging strains. Addressing these challenges requires a multisectoral approach. Stakeholders should train clinicians in managing patients with known and unknown aetiologies, provide medical equipment, enhance surveillance across districts, and heighten awareness of early healthcare-seeking during outbreaks.

 

 

The study found a relatively higher COVID-19 CFR in Sierra Leone than the regional estimate. Older age, fever, difficulty breathing, coma, as well as underlying conditions like HIV/AIDS, diabetes, and hypertension, were significant factors associated with COVID-19 death. Geographic variations in COVID-19 death rates highlight the need to strengthen healthcare support in regions with higher mortality. The considerable number of deaths occurring outside healthcare settings suggests potential barriers to accessing timely medical care and a low tendency to seek healthcare, underscoring the need for improved access and public awareness. We recommend that the Ministry of Health prioritize protecting older adults and individuals with comorbidities by enhancing vaccination efforts, implementing regular health monitoring, and ensuring timely access to early treatment to reduce COVID-19 mortality effectively.

 

 

The authors declare no competing interests.

 

 

Conceptualization and design: Stephen L M Kamara; Data Collection: Stephen L M Kamara, Joel Mansaray, Binta Bah; Analysis and Interpretation: Stephen L M Kamara, Adel Hussein Elduma, Umaru Sesay, Magoba Bridget, James. Sylvester,Squire, Gebrekrstos Negash Gebru; Drafting and Review of Manuscript: Stephen L M Kamara, Adel Hussein Elduma, Umaru Sesay, Solomon Aiah Sogbe, Amara Alhaji Sheriff, James. Magoba Bridget, Sylvester, Squire, Binta bah, Gebrekrstos Negash Gebru. All authors approve its submission for publication.

 

 

Table 1: Socio-demographic characteristics of Covid -19 cases in Sierra Leone, March 2020-2022 (N=8595)

Table 2: Clinical presentations related to COVID-19 cases in Sierra Leone, March 2020 - 2022, (N=8595)

Table 3: Pre-existing conditions among COVID-19 cases in Sierra Leone March 2020 - March 2022, (N=8595)

Table 4: Logistic regression analysis of factors associated with COVID-19 deaths, Sierra Leone, March 2020 - March 2022

 

 

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