Seroprevalence of SARS-CoV-2 antibodies and knowledge, attitude and practice toward COVID-19 in the Republic of Srpska-Bosnia & Herzegovina: A population-based study

The Second Round of a Population-Based Seroprevalence Study of Anti-SARS-CoV-2 Antibodies and COVID-19 Vaccination Assessment in the Republika Srpska, Bosnia and Herzegovina

INTRODUCTION

The aim of the study was to assess the seroprevalence of SARS-CoV-2 in the Republika Srpska, Bosnia and Herzegovina, after five waves of COVID-19 and 1 year after introduction of vaccination to better understand the true extent of the COVID-19 pandemic in the population of the Republika Srpska and role of vaccination in achieving herd immunity.

METHODS

The population-based study was conducted from December 2021 to February 2022 in a group of 4463 individuals in the Republika Srpska. Total anti-SARS-CoV-2 antibodies were determined in serum specimens using the Wantai total antibody ELISA assay. Quantitative analysis, using Kantaro IgG assays, was performed in subsamples (1273 specimens) to asses and compare levels of IgG among vaccinated, recovered and participants with hybrid immunity. To adjust for age and gender distribution in sample, poststratification method is applied.

RESULTS

The overall cumulative seroprevalence was 94.6% (95% CI = 93.9-95.3). Significantly higher seroprevalence rates were observed among vaccinated 97.8% (95% CI = 97.3-98.4) comparing to unvaccinated participants (89.5%, 95% CI = 88.0-91.0). Seroprevalence increases with the number of received doses. Among various professions, the highest seroprevalence was found in the service industry (98.1%), education (98.0%) and healthcare (96.9%). We found that 2.2% of vaccinated and 3.6% of participants with SARS-CoV-2 positivity during 2021 had no detectable IgG antibodies. Both seroprevalence (98.6%) and antibody titres (1094.4 AU/mL) were significantly higher among people with hybrid immunity.

CONCLUSION

Our findings reveal a 2.3-fold increase in seroprevalence of SARS-CoV-2 antibodies due to infection and vaccination, comparing to the first study performed 1 year earlier. This study provides better understanding of the SARS-CoV-2 transmission and highlights the important role of the vaccination in achieving the population immunity. Periodically conducted population-based seroprevalence studies are important to understand temporal trends and assess surveillance system performance and public compliance with vaccination policies.

Clinical and epidemiological risk factors associated with hospitalization and mortality rate of COVID-19 patients in Banja Luka County: A retrospective observational cohort study on 40,000 patients

Context

Since beginning of the coronavirus disease (COVID-19) it became clear that severe forms of this infection have primarily affected patients with chronic conditions.

Aims

The aim of the study was to explore clinical and epidemiological characteristics associated with COVID 19 outcomes.

Settings and Design

The retrospective observational study included 40,692 citizens of Banja Luka County, Bosnia and Herzegovina, who were confirmed as reverse transcriptase polymerase chain reaction (RT-PCR) positive on COVID-19 at a primary healthcare centre from March 2020 to September 2022.

Methods and Materials

Epidemiological data were obtained from Web-Medic medical records of patients. The COVID-19 data were obtained from COVID-19 data sheets comprised of patients' RT-PCR testing forms, surveillance forms for severe acute respiratory syndrome coronavirus-2 status, and a map of their positive and isolated contacts.

Statistical Analysis Used

Differences regarding the distributions of patients between groups were analysed using the Pearson chi-square test and Mantel-Haenszel chi-square test for trends, while differences in mean values were compared using an independent sample t-test.

Results

The average age of hospitalised patients was significantly higher compared to the age of non-hospitalised patients (P < 0.001). The average age of patients with lethal outcomes was nearly twice as high in comparison to patients with non-lethal outcomes (P < 0.001). Male patients had a higher hospitalization and mortality rate (P < 0.001). The highest hospitalization rate was in patients with chronic renal failure (CRF), diabetes and cardiovascular diseases (CVDs), while the death rate was the highest among patients with CRF and hearth comorbidities. Patients with fatigue and appetite loss had a higher percentage of lethal outcomes. Vaccinated patients had a significantly lower rate of lethal outcome.

Conclusions

Clinical symptoms, signs and outcomes, are posing as predictive parameters for further management of COVID-19. Vaccination has an important role in the clinical outcomes of COVID-19.

The prevalence of SARS-CoV-2 antibodies within the community of a private tertiary university in the Philippines: A serial cross sectional study

The COVID-19 pandemic has caused a public health emergency in all sectors of society, including universities and other academic institutions. This study determined the seroprevalence of SARS-CoV-2 antibodies among administrators, faculty, staff, and students of a private tertiary academic institution in the Philippines over a 7 month period. It employed a serial cross-sectional method using qualitative and quantitative COVID-19 antibody test kits. A total of 1,318 participants were tested, showing 47.80% of the study population yielding IgG antibodies to SARS-CoV-2 virus. A general increase in seroprevalence was observed from June to December 2021, which coincided with the vaccine roll-out of the country. All brands yielded positive antibody formation, with mRNA vaccines having higher levels than other types of vaccines. A decreasing trend in IgG reactivity was found in vaccinated individuals after 1 to 6 months of completion of the 2 doses of the COVID-19 vaccine. Where possible, IgG and T-cell reactivity and/or neutralizing capacity against SAR-CoV-2 need to be monitored regardless of vaccine brand. Together with uptake of COVID-19 vaccines and boosters, other public health interventions such as wearing of masks and regular testing need to be continued for better protection. Effective communication is also needed to inform risks associated with activities across different settings. Investments in long-term measures such as air filtration and ventilation systems, and wastewater surveillance need to be made.

Consumption of Antibiotics in Primary Care Setting before and during COVID-19 Pandemic in Republic of Srpska, Bosnia and Herzegovina

The pandemic of COVID-19 has brought many changes in health care systems at all levels of health care. The increase in the number of cases of COVID-19 has led to overuse and misuse of antibiotics.The aim of this study was to compare the consumption of antibiotics for systemic use in outpatients in the Republic of Srpska (RS), before and during the first year of the COVID-19 pandemic, as well as the association between antibiotic consumption and the rate of incidence and mortality of COVID-19. The total consumption of the antibiotics for systemic use (J01) in outpatients in the Republic of Srpska during 2019 was 19.40 DDD/TID, with an increase to 30.80 DDD/TID in 2020.Significantly higher use of penicillin (10.58 ± 11.01 DDD/TID in 2019 vs. 17.10 ± 13.63 DDD/TID in 2020), cephalosporins (2.68 ± 1.90 DDD/TID in 2019 vs. 5.93 ± 2.77 DDD/TID in 2020) and macrolides (2.14 ± 2.22 DDD/TID in 2019 vs. 3.40 ± 3.44 DDD/TID in 2020) was observed during the pandemic period. It is necessary to improve the prescribing practice of antibiotics at the primary health care level, public awareness about rational use of antibiotics, as well as the current antibiotic stewardship programs and control their implementation.