Predictors of mortality among COVID-19 patients at Kilimanjaro Christian Medical Centre in Northern Tanzania: A hospital-based retrospective cohort study (preprint)

Background: COVID-19 disease is a global public health disaster causing a range of social, economic, and healthcare difficulties, border restrictions, high human loss, lockdown, and transportation challenges. Despite it being a global pandemic, there are few studies conducted in Tanzania to examine the predictors of mortality. This disease has caused a significant number of mortalities worldwide but literature shows low mortality and better survival in Africa than in other WHO regions. Therefore, this study aimed to determine the predictors of mortality among COVID-19 patients at KCMC Hospital in Northern Tanzania. Methodology This was the hospital-based retrospective cohort study, conducted at KCMC Hospital in Northern Tanzania among all admitted patients with confirmed COVID-19, from 10th March 2020 to 26th January 2022. The main study event was COVID-19 mortality. The predictors of mortality were determined by using the Weibull survival regression model and the statistically significant results were declared at a p-value of <0.05. Results A total of 547 confirmed COVID-19 patient records were included in the study. Their median age was 63 (IQR; 53-83), about 60% were aged 60 years and above, and 56.7% were males. The most common clinical features were; fever (60.8%), a severe form of the disease (44.4%), difficulty in breathing (73.3%), chest pain (46.1%), and generalized body weakness (71.3%). Of all participants, over one-third (34.6%) died (95%CI; 0.31-0.39). The median survival time was 7 days (IQR; 3-12). The overall mortality rate was 32.33 per 1000 person-days while the independent predictors of higher mortality risk were age ≥60 years (AHR=2.01; 95%CI 1.41-2.87; P<0.001), disease severity (AHR=4.44; 95%CI 2.56-7.73; P<0.001) and male sex (AHR=1.28; 95%CI; 0.93-1.73; P=0.128). Conclusion Mortality was higher in elderly male patients, with a severe form of the disease and those with any comorbidities. Therefore, more attention should be provided to older patients including uptake of the current vaccine and ensuring standard and supportive care at primary health facilities is available.

Neutrophil-to-Lymphocyte Ratio as a Prognostic Indicator in COVID-19: Evidence from a Northern Tanzanian Cohort (preprint)

Background: COVID-19 caused a profound global impact, resulting in significant cases and deaths. The progression of COVID-19 clinical manifestations is influenced by a dysregulated inflammatory response. Early identification of the subclinical progression is crucial for timely intervention and improved patient outcomes. While there are various biomarkers to predict disease severity and outcomes, their accessibility and affordability pose challenges in resource-limited settings. We explored the potentiality of the neutrophil-to-lymphocyte ratio (NLR) as a cost-effective inflammatory marker to predict disease severity, clinical deterioration, and mortality in affected patients. Methodology: A hospital-based retrospective cohort study was conducted at KCMC Hospital among COVID-19 patients followed from admission to discharge between 1st March 2020 and 31st March 2022. NLR was calculated as the absolute neutrophil count in µL divided by the absolute lymphocyte count in μL. The NLR cut-off value was determined using Receiver Operating Characteristic (ROC) analysis and assessed its predictive ability at admission for in-hospital mortality. The Chi-square test compared the proportion of NLR by patient characteristics. The association of NLR with disease severity and mortality was analyzed using the modified Poisson and Cox regression models, respectively. Results: The study included 504 patients, with a median age of 64 years, 57.1% were males, and 68.3% had severe COVID-19. The in-hospital COVID-19 mortality rate was 37.7%. An NLR cutoff value of 6.1 or higher had a sensitivity of 92.1% (95% CI 89.2%–94.0%) and a specificity of 92.0% (95% CI 89.7%–94.4%). Additionally, 39.5% of patients with an NLR value of 6.1 or higher had increased risk of severe disease, subsequent clinical deterioration, and mortality. Conclusion and recommendation: An NLR value of 6.1 or higher at the time of hospital admission associated with severe disease, clinical deterioration, and mortality in patients with COVID-19. Integration of NLR as a prognostic parameter in COVID-19 prognosis scales could improve risk assessment and guide appropriate management strategies for COVID-19 patients, as well as for potential future viral-related pneumonias. Further prospective studies are necessary to validate these findings and evaluate the clinical utility of NLR in larger cohorts of patients.

Health care workers self-perceived infection risk and COVID-19 vaccine uptake: a mixed methods study (preprint)

Background: Vaccination is the most cost-effective way of preventing COVID-19 disease although there was a considerable delay in its institution in Tanzania. This study aimed to assess healthcare workers (HCWs) self-perceived infection risk and uptake of COVID-19 vaccines. Methods: A concurrent embedded, mixed methods research design was utilized to collect data among HCWs in seven Tanzanian regions. Quantitative data was collected using a validated, pre-piloted, interviewer administered questionnaire whereas in-depth interviews and focus group discussions gathered qualitative data. Descriptive analyses were performed, and chi-square test used to test for associations across categories. Thematic analysis was used to analyze the qualitative data. Results: A total of 1,386 HCWs responded to the quantitative tool, 26 participated in the in-depth interviews and 74 in the focus-group discussions. About half of the HCW (53.6%) reported to have been vaccinated and three quarters (75.5%) self-perceived to be at a high risk of acquiring COVID-19 infection. Participants perceived that the nature of their work and the working environment in the health facilities increases their risk to infection. Limited availability and use of personal protective equipment was reported to elevate the perceived risks to the infection. Respondents belonging in the oldest age group and from low and mid-level health care facilities had higher proportions with a high-risk perception of acquiring COVID-19 infection compared to their counterparts. Conclusions: Only about half of the HCWs reported to be vaccinated albeit the majority recounted higher perception of risk to contracting COVID-19 due to their working environment, including limited availability and use of personal protective equipment. Efforts to address heightened perceived-risks should include improving the working environment, availability of PPEs and continue updating HCWs on the benefits of COVID-19 vaccine to limit their risks to the infection and consequent transmission to their patients and public.