Medicinal Chemistry in Bosnia and Herzegovina - Past, Present and Perspectives.

Although Bosnia and Herzegovina has had a rich history in medicines and traditional medicines, it historically had poor activity regarding the field of medicinal chemistry in the country. However, this has changed recently as Bosnia and Herzegovina has shown immense potential in this field. A significant milestone occurred in 2019, with the establishment of the Organization Pharmaceutical Research Institute. This non-governmental organization aims to improve medicinal chemistry in Bosnia and Herzegovina. Through research, partnerships, and educational initiatives, the organization has made substantial strides in promoting pharmaceutical research, education, and innovation. Moreover, the country's membership in the European Federation for Medicinal Chemistry and Chemical Biology (EFMC) has further facilitated collaboration with European experts, access to cutting-edge knowledge and technologies, and harmonization with European standards. Looking to the future, this organization endeavors to improve healthcare, encourage innovation in medicinal chemistry, and promote the development of new therapies. With the efforts to establish an Association of Chemists in Bosnia and Herzegovina, the nation's scientific community is poised to flourish, contributing to the advancement of medicinal chemistry and healthcare in the region.

Trends in SARS-CoV-2 Cycle Threshold Values in Bosnia and Herzegovina-A Retrospective Study.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which led to the COVID-19 pandemic, has significantly impacted global public health. The proper diagnosis of SARS-CoV-2 infection is essential for the effective control and management of the disease. This study investigated the SARS-CoV-2 infection using RT-qPCR tests from laboratories in Bosnia and Herzegovina. We performed a retrospective study of demographic data and Ct values from 170,828 RT-qPCR tests from April 2020 to April 2023, representing 9.3% of total national testing. Samples were collected from 83,413 individuals across different age groups. Of all tests, 33.4% were positive for SARS-CoV-2, with Ct values and positivity rates varying across demographics and epidemic waves. The distribution was skewed towards older age groups, although lower positivity rates were observed in younger age groups. Ct values, indicative of viral load, ranged from 12.5 to 38. Lower Ct values correlated with higher positive case numbers, while higher Ct values signaled outbreak resolution. Additionally, Ct values decreased during epidemic waves but increased with the dominance of certain variants. Ct value-distribution has changed over time, particularly after the introduction of SARS-CoV-2 variants of interest/concern. Established Ct value trends might, therefore, be used as an early indicator and additional tool for informed decisions by public health authorities in SARS-CoV-2 and future prospective pandemics. Moreover, they should not be overlooked in future epidemiological events.

High genetic diversity of Anaplasma ovis in sheep from Bosnia and Herzegovina.

BACKGROUND: Ovine anaplasmosis (sensu stricto) is a rickettsial blood disease caused by the tick-borne species Anaplasma ovis. The disease is characterized by mild anemia, fever, and icterus. A more severe clinical presentation is possible in non-endemic areas. There is no existing data on the presence of Anaplasma ovis in Bosnia and Herzegovina. However, given the country's location within the Mediterranean Basin and the recent molecular detection of Babesia ovis, it is plausible that sheep in the region could naturally be infected with this tick-borne pathogen. METHODS AND RESULTS: Blood samples from 81 sheep in the Podrinje and Herzegovina areas were examined by PCR. PCR positivity was found in 38 (46.9%) cases indicating a high number of infected sheep. Mixed infections with Babesia ovis and A.ovis were observed in 63.3% of cases. A higher number of positive sheep was recorded in the area of Herzegovina. Phylogenetic analysis of the gltA, groEL, and msp4 genes of A. ovis revealed numerous genotypes and significant genetic variability. This diversity was not related to geographic origin, tick-borne infection status, or sheep breeding practices in Podrinje and Herzegovina. CONCLUSIONS: The data obtained in this study suggest that the emergence of new genotypes and the high genetic variability of A. ovis are driven by specific local and micro-environmental factors.

Measles outbreak in 2019: a warning for the post-COVID-19 pandemic period.

Introduction. At the end of 2019 and the year before, there was a significant spread of measles in the World Health Organization (WHO) European Region.Gap statement. Among the countries that reported, a measles outbreak was Bosnia and Herzegovina (BiH).Aim. To describe the measles outbreak in BiH (an entity of the Federation of BiH, FBiH) in 2019.Methodology. Confirmatory IgM serology, measles nucleic acid detection by real-time RT-PCR and virus genotyping were done in the WHO-accredited laboratory for measles and rubella at the Clinical Center of the University of Sarajevo, Unit for Clinical Microbiology. Genotype was determined in all measles-RNA-positive cases by sequence analysis of the 450 nt fragment coding the C-terminal of measles virus nucleoprotein (N).Results. From 1 January to 31 December 2019, 1332 measles cases were reported, with the peak observed in April 2019 (413/1332, 31.01 %). Sarajevo Canton had the highest incidence, number of cases and percentage (206.4; 868/1332; 65.17 %) of measles cases. Around four-fifths of infected persons were unvaccinated (1086/1332, 81.53 %), while 4.58 % of the patients (61/1332) were immunized with one dose of measles-containing vaccine. The highest proportion of cases was found in children 0-6 years of age (738/1332, 55.41 %). Measles IgM positivity was determined in 75.88 % (346/456), while virus RNA was detected in 82.46 % (47/57) of the swab samples. All measles virus sequences belonged to genotype B3. SNP (position 216: C=>T) was detected in 1 of the 40 sequences obtained during this outbreak.Conclusion. Due to suboptimal immunization coverage, BiH belongs to countries at a high risk for measles outbreaks. Post-COVID-19 (coronavirus disease 2019) pandemic, targeted and tailored strategies are required to ensure routine vaccination demand and acceptance and broad partner and stakeholder group participation.

A brief history of neurosurgery in Bosnia and Herzegovina: historical vignette.

The modern period of neurosurgery in Bosnia and Herzegovina began with the first neurosurgical procedure performed by Dr. Karl Bayer in 1891 on 3 patients with depressed skull fractures and epilepsy. In 1956 the Department of Surgery in Sarajevo designated several beds specifically for a neurosurgical unit. A significant milestone in the history of neurosurgery in Bosnia and Herzegovina was the establishment of the Division of Neurosurgery at the Clinical Center University of Sarajevo in 1970. The first neurosurgeon to complete his training in Bosnia and Herzegovina was Dr. Faruk Konjhodzic. The first female neurosurgeon was Dr. Nermina Iblizovic. Presently, there are 7 neurosurgical departments in the country, located in Sarajevo, Tuzla, Zenica, Mostar, Banja Luka, Bihac, and Foca. The Association of Neurosurgeons in Bosnia and Herzegovina, founded in 2003, is a member of the European Association of Neurosurgical Societies and the World Federation of Neurosurgical Societies. The aim of this historical paper is to provide a concise chronology of important events and mention key individuals who have contributed to the development of modern neurosurgery in Bosnia and Herzegovina.

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.

Changes in management of head and neck malignancies during the COVID-19 pandemic.

Objective: Despite multiple studies from high-income countries, reports from low- and middle-income countries on the impact of COVID-19 on head and neck cancer care remain sparse. This study aimed to assess the effects of the COVID-19 pandemic on head and neck cancer patients at a tertiary reference centre in Bosnia and Herzegovina. Methods: We included 228 patients with malignant head and neck tumours evaluated and treated between January 1, 2019, and December 31, 2021. Patient demographics, histological characteristics, and treatment modalities were retrospectively obtained and compared between the pre-pandemic period (pre-COVID-19 group) and the period after the implementation of COVID-19 restrictive measures (COVID-19 group). Results: Patients were significantly older during the COVID-19 pandemic. In particular, 63 patients (44.7%) were under 65 and 78 (55.3%) were 65 or older, while in the pre-COVID-19 period, 53 patients (60.9%) were under 65 and 34 (39.1%) were 65 or older (p = 0.017). The pre-COVID-19 and COVID-19 groups did not significantly differ regarding other patient- and tumour characteristics, or primary treatment modalities. Conclusions: During the COVID-19 pandemic, significantly fewer patients were under 65 at the time of initial work-up, potentially reflecting the more enhanced disease-related anxiety of the younger population. Future studies are warranted to address this population's specific educational and psychological needs to ensure appropriate cancer care.

Tick-Borne Pathogens in Dermacentor reticulatus Ticks from Bosnia and Herzegovina.

Dermacentor (D.) reticulatus ticks carry and transmit a wide range of pathogens to vertebrate hosts. Limited information is available about the existence of emerging tick-borne pathogens and the distribution of D. reticulatus in Bosnia and Herzegovina. The study aimed to investigate the occurrence and distribution of D. reticulatus and to detect the presence of Anaplasma spp., Borrelia (B.) burgdorferi s.l., Rickettsia spp., and Babesia spp. in samples originating from questing ticks and ticks collected from domestic animals in various regions of Bosnia and Herzegovina. A total of 402 collected D. reticulatus ticks were widely distributed throughout the country. Of the 41 pools consisting of 205 individual D. reticulatus ticks, 21 (51.2%) indicated the presence of Rickettsia spp., 17 (41.4%) of Babesia spp., 2 (4.8%) of Anaplasma spp., and 1 (2.4%) of B. burgdorferi s.l. after real-time PCR screening. Our study indicates that D. reticulatus has significantly expanded its distribution and host range in Bosnia and Herzegovina. Moreover, our results represent the first detection of Babesia spp. in D. reticulatus in Bosnia and Herzegovina. Given the demonstrated presence of emerging pathogens in questing and feeding ticks, there is an urge to establish a surveillance system for ticks and tick-borne pathogens in Bosnia and Herzegovina.

Application of machine learning models and landsat 8 data for estimating seasonal pm 2.5 concentrations.

Air pollution is a significant global challenge that affects many cities. In Europe, Bosnia and Herzegovina (BiH) are among the most highly polluted and are mainly affected by air pollution. In this study, we integrate open-source landsat 8 remote sensing products, topographical data, and the limited ground truth PM2.5 data to spatially predict the air quality level across different seasons in Tuzla Canton, BiH by adopting three pre-existing machine learning models, namely XGBoost, K-Nearest Neighbour (KNN) and Naive Bayes (NB). These classification models were implemented based on landsat 8 bands, environmental-derived indices, and topographical variables generated for the study area. Based on the predicted results, the XGBoost model exhibited the highest overall accuracy across all seasons. The predicted model results were used to generate spatial air quality maps. Based on the classification maps, the PM2.5 air quality level predicted for Tuzla Canton in the Winter Season is very unhealthy. The findings conclude that the PM2.5 air quality concentration in Tuzla Canton is relatively unsatisfactory and requires urgent intervention by the government to prevent further deterioration of air quality in Tuzla and other affected cantons in BiH.

Updated Surveillance Metrics and History of the COVID-19 Pandemic (2020-2023) in Europe: Longitudinal Trend Analysis.

BACKGROUND: In this study, we built upon our initial research published in 2020 by incorporating an additional 2 years of data for Europe. We assessed whether COVID-19 had shifted from the pandemic to endemic phase in the region when the World Health Organization (WHO) declared the end of the public health emergency of international concern on May 5, 2023. OBJECTIVE: We first aimed to measure whether there was an expansion or contraction in the pandemic in Europe at the time of the WHO declaration. Second, we used dynamic and genomic surveillance methods to describe the history of the pandemic in the region and situate the window of the WHO declaration within the broader history. Third, we provided the historical context for the course of the pandemic in Europe in terms of policy and disease burden at the country and region levels. METHODS: In addition to the updates of traditional surveillance data and dynamic panel estimates from the original study, this study used data on sequenced SARS-CoV-2 variants from the Global Initiative on Sharing All Influenza Data to identify the appearance and duration of variants of concern. We used Nextclade nomenclature to collect clade designations from sequences and Pangolin nomenclature for lineage designations of SARS-CoV-2. Finally, we conducted a 1-tailed t test for whether regional weekly speed was greater than an outbreak threshold of 10. We ran the test iteratively with 6 months of data across the sample period. RESULTS: Speed for the region had remained below the outbreak threshold for 4 months by the time of the WHO declaration. Acceleration and jerk were also low and stable. While the 1-day and 7-day persistence coefficients remained statistically significant, the coefficients were moderate in magnitude (0.404 and 0.547, respectively; P<.001 for both). The shift parameters for the 2 weeks around the WHO declaration were small and insignificant, suggesting little change in the clustering effect of cases on future cases at the time. From December 2021 onward, Omicron was the predominant variant of concern in sequenced viral samples. The rolling t test of speed equal to 10 became insignificant for the first time in April 2023. CONCLUSIONS: While COVID-19 continues to circulate in Europe, the rate of transmission remained below the threshold of an outbreak for 4 months ahead of the WHO declaration. The region had previously been in a nearly continuous state of outbreak. The more recent trend suggested that COVID-19 was endemic in the region and no longer reached the threshold of the pandemic definition. However, several countries remained in a state of outbreak, and the conclusion that COVID-19 was no longer a pandemic in Europe at the time is unclear.

Diversity of Trichinella species in carnivores from Bosnia and Herzegovina.

BACKGROUND: In Bosnia and Herzegovina, domestic and wild carnivores represent a significant driver for the transmission and ecology of zoonotic pathogens, especially those of parasitic aetiology. Nevertheless, there is no systematic research of Trichinella species in animals that have been conducted in Bosnia and Herzegovina, even though trichinellosis is considered the most important parasitic zoonosis. The available results of the few studies carried out in Bosnia and Herzegovina are mainly related to the confirmation of parasitic larvae in the musculature of domestic pigs and wild boars or data related to trichinellosis in humans. The objective of our study was to present the findings of a comprehensive investigation into the species composition of Trichinella among 11 carnivorous species within the territory of Bosnia and Herzegovina, as follows: red fox (Vulpes vulpes), grey wolf (Canis lupus), brown bear (Ursus arctos), wildcat (Felis silvestris), pine marten (Martes martes), European badger (Meles meles), weasel (Mustela nivalis), European polecat (Mustela putorius), Eurasian lynx (Lynx lynx), but also dog (Canis lupus familiaris) and cat (Felis catus). RESULTS: In the period 2013-2023, carnivore musculature samples (n = 629), each consisting of 10 g of muscle tissue, were taken post-mortem and individually examined using the artificial digestion method. In the positive samples (n = 128), molecular genotyping and identification of parasitic larvae of Trichinella spp. were performed using a PCR-based technique up to the species/genotype level. Positive samples were used for basic PCR detection of the genus Trichinella (rrnS rt-PCR technique) and genotyping (rrnl-EVS rt-PCR technique). The Trichinella infection was documented for the first time in Bosnia and Herzegovina among red foxes, grey wolves, brown bears, dogs, badgers and Eurasian lynx, with a frequency rate of 20.3%. Additionally, the presence of T. britovi infection was newly confirmed in Bosnia and Herzegovina, marking the initial documented cases. Furthermore, both T. britovi and T. pseudospiralis infections were observed in the wildcat population, whereas T. britovi and T. spiralis infections were detected in pine martens. Consistent with previous research, our findings align particularly regarding carnivores, with data from other countries such as Germany, Finland, Romania, Poland and Spain, where T. britovi exhibits a wider distribution (62.5-100%) compared to T. spiralis (0.0-37.5%). T. britovi is more common among sylvatic carnivores (89.0%), while T. spiralis prevails in wild boars (62.0%), domestic swine (82.0%) and rodents (75.0%). CONCLUSION: The results of our study represent the first molecular identification of species of the genus Trichinella in Bosnia and Herzegovina. Additionally, our findings underscore the necessity for targeted epidemiological studies to thoroughly assess trichinellosis prevalence across diverse animal populations. Considering the relatively high frequency of trichinellosis infection in investigated animal species and its public health implications, there is an evident need for establishing an effective trichinellosis surveillance system in Bosnia and Herzegovina.

Mpox virus DNA detection in different clinical specimens: tertiary-level laboratory experience, Bosnia and Herzegovina, 2022.

Mpox virus (MPXV) infection is difficult to distinguish from other (non-)infectious diseases. The etiology of rash can be differentiated by real-time polymerase chain reaction (rtPCR) on different types of samples. The study aims to provide experience with emerging MPXV diagnostics in a tertiary-level laboratory in Bosnia and Herzegovina. From July-December 2022, a total of 18 mpox suspected persons were tested. MPXV infection was confirmed by rtPCR in 10/18 (55.56 %) persons. The number of cases reached a peak in October 2022. The lowest median Crossing point (Cp) (x̄ = 29.76) was obtained from a swab of skin lesions in a viral transport medium (VTM). Evaluating the Cp values for the 7/9 mpox cases from whom paired swab samples from different anatomic sites were collected, higher positivity of skin lesion swabs in VTM was observed. In conclusion, our data highlighted the confirmatory role of rtPCR in the diagnosis of MPXV in skin lesion samples.

Ongoing measles outbreak, the Federation of Bosnia and Herzegovina, December 2023 to February 2024.

We report on an ongoing measles outbreak in the Federation of Bosnia and Herzegovina with 141 cases notified between week 52 2023 and week 6 2024. Among those with known vaccination status, 97% were unvaccinated and the most affected group is children under the age of 5 years (n = 87) who were not vaccinated during the pandemic years. Sixty-eight cases were hospitalised, the most common complications were measles-related pneumonia and diarrhoea. The sequenced measles viruses from four cases belonged to genotype D8.

Comparison between conventional open-heart valve surgery and minimally invasive valve replacement surgery regarding the length of hospital stay and usage of blood derivates: insights from a single-centre, single-surgeon study conducted in Bosnia and Herzegovina.

Aim To analyse the correlation between different surgical methodologies employed in valve diseases treatment and their subsequent impact on the duration of hospitalization. Methods This retrospective study conducted at the Clinical Centre of the University of Sarajevo analysed medical records of 163 valve disease patients treated between January 2019 and November 2022. The patients were divided into two groups: 77 had openheart valve surgery and 86 underwent minimally invasive cardiac surgery (MICS). Results The mean duration of the surgical procedures was 3.9±1.3 hours, with conventional open-heart surgery requiring an average of 3.6±1.1 hours and minimally invasive cardiac surgery (MICS) procedure 4.2±1.5 hours. No substantial disparities were found in the total length of hospitalization between the two groups, as both conventional (8.2±4.5 days) and MICS (8.7±7.0 days) demonstrated similar duration. Similarly, the total duration of intensive care unit (ICU) stay displayed similarity, with conventional surgery patients staying an average of 3.9±2.8 days and MICS patients of 4.2±4.1 days. The pattern of blood transfusion and fresh-frozen plasma usage revealed higher rates in the conventional valve surgery group comparing to the MICS group. Conclusion Minimally invasive valve surgery, despite slightly longer operative times, resulted in lower blood transfusion requirements and comparable hospitalization and ICU stay.

Asymmetric impact of microfinance on economic growth: Evidence from Bosnia and Herzegovina.

This study explores the correlation between microfinance loans (MFL) and economic growth in Bosnia and Herzegovina (Bosnia). It utilizes the non-linear Autoregressive Distributed Lag (NARDL) method to examine cointegration and short-run dynamics by analyzing quarterly data spanning from 2010 to 2022. The findings underscore the link between MFL shocks and long-term economic growth. The study unveils the unique effects of both positive and negative MFL shocks on growth, suggesting a non-linear relationship between microfinance loans and economic growth in Bosnia. However, the study concludes that the impact of MFL on Bosnia's GDP is adverse. Short-term fluctuations in MFL show no substantial influence on Bosnian economic growth. The coefficient of the error correction model is both negative and significant indicating the stability of the long-term relationship. This implies a rapid correction, with 46.4 % of the previous quarter's imbalance rectified within the current quarter. While our results are based on a single country, they align with recent criticisms of microfinance practices. Furthermore, our study offers a novel approach as it represents the first examination of the asymmetric relationship between MFL and GDP in Bosnia, providing valuable policy recommendations.

Metagenomic Sequencing of Lloviu Virus from Dead Schreiber's Bats in Bosnia and Herzegovina.

Bats are a natural host for a number of viruses, many of which are zoonotic and thus present a threat to human health. RNA viruses of the family Filoviridae, many of which cause disease in humans, have been associated with specific bat hosts. Lloviu virus is a Filovirus which has been connected to mass mortality events in Miniopterus schreibersii colonies in Spain and Hungary, and some studies have indicated its immense zoonotic potential. A die-off has been recorded among Miniopterus schreibersii in eastern Bosnia and Herzegovina for the first time, prompting the investigation to determine the causative agent. Bat carcasses were collected and subjected to pathological examination, after which the lung samples with notable histopathological changes, lung samples with no changes and guano were analyzed using metagenomic sequencing and RT-PCR. A partial Lloviu virus genome was sequenced from lung samples with histopathological changes and found to be closely related to Hungarian and Italian virus sequences. Further accumulation of mutations on the GP gene, coding the glycoprotein responsible for cell tropism and host preference, enhances the need for further characterization and monitoring of this virus to prevent spillover events and protect human health.

Molecular characterization and phylogenetic analysis of highly pathogenic H5N1 clade 2.3.4.4b virus in Bosnia and Herzegovina.

Influenza A virus continues to represent a growing problem affecting mainly birds but with an increasing number of mammal transmission events reported each year. Nevertheless, molecular characterization and phylogenetic analysis of influenza A viruses originating from all confirmed cases have not been systematically performed in all parts of the world. In this study, we investigated a sample originating from a mute swan that died in November 2021 in the northern part of Bosnia and Herzegovina with RT-qPCR and whole genome sequencing using ONT MinION. It was diagnosed as a highly pathogenic Influenza A virus, subtype H5N1 of 2.3.4.4b clade, and phylogenetic analysis revealed high sequence homology with other European HPAI H5N1 sequences at the time. The notable detected mutations in HA (N110S and T139P) and NA genes (H155Y), that facilitate the host specificity shift and enable the resistance to some antiviral drugs respectively, underscore the necessity of virus evolution surveillance. Therefore, the rapid dissemination of information, including virological and molecular data, is essential for the introduction of tailored prevention measures for infected animals, providing clearer insight and better awareness of a potential public health threat.

Correlation analysis of different optical remote sensing indices for drought monitoring: a case study of Canton Sarajevo, Bosnia and Herzegovina.

Droughts are second to hurricanes the world's most costly weather events. Damage caused by droughts in certain countries is measured in tens of billions of dollars per year. Timely detection of drought and prediction of its occurrence has the potential to reduce costs and save a large number of people from its consequences. Numerous methods that serve this purpose exist in scientific research and practice. One group of drought monitoring methods belongs to the field of remote sensing, where it is possible to monitor drought indicators over large areas in almost real-time through satellite images. This paper is focused on the optical indices of remote sensing calculated by raster algebra. The intention was to reach conclusions about the quality of individual indices used for the Canton Sarajevo area in Bosnia and Herzegovina for each month of August in the period 2008-2021 through correlational and qualitative analysis and the use of meteorological indicators. Among the used indices, NDVI (normalized difference vegetation index) and NMI (normalized moisture index) proved to be the most reliable, and their mutual correlation was very strong (r = 0.99).

Evolution of seroprevalence to SARS-CoV-2 in blood donors in Sarajevo Canton, Federation of Bosnia and Herzegovina: Cross-sectional and longitudinal studies.

Background: Sarajevo Canton in the Federation of Bosnia and Herzegovina has recorded several waves of high SARS-CoV-2 transmission and has struggled to reach adequate vaccination coverage. We describe the evolution of infection- and vaccine-induced SARS-CoV-2 antibody response and persistence. Methods: We conducted repeated cross-sectional analyses of blood donors aged 18-65 years in Sarajevo Canton in November-December 2020 and 2021. We analyzed serum samples for anti-nucleocapsid (anti-N) and anti-spike (anti-S) antibodies. To assess immune durability, we conducted longitudinal analyses of seropositive participants at 6 and 12 months. Results: One thousand fifteen participants were included in Phase 1 (November-December 2020) and 1152 in Phase 2 (November-December 2021). Seroprevalence increased significantly from 19.2% (95% CI: 17.2%-21.4%) in Phase 1 to 91.6% (95% CI: 89.8%-93.1%) in Phase 2. Anti-S IgG titers were significantly higher among vaccinated (58.5%) than unvaccinated infected participants across vaccine products (p < 0.001), though highest among those who received an mRNA vaccine. At 6 months, 78/82 (95.1%) participants maintained anti-spike seropositivity; at 12 months, 58/58 (100.0%) participants were seropositive, and 33 (56.9%) had completed the primary vaccine series within 6 months. Among 11 unvaccinated participants who were not re-infected at 12 months, anti-S IgG declined from median 770.1 (IQR 615.0-1321.7) to 290.8 (IQR 175.7-400.3). Anti-N IgG antibodies waned earlier, from 35.4% seropositive at 6 months to 24.1% at 12 months. Conclusions: SARS-CoV-2 seroprevalence increased significantly over 12 months from end of 2020 to end of 2021. Although individuals with previous infection may have residual protection, COVID-19 vaccination is vital to strengthening population immunity.

The role of National Immunization Technical Advisory Groups in advising COVID-19 immunization policy during the pandemic: lessons from the Federation of Bosnia and Herzegovina.

A National Immunization Technical Advisory Group (NITAG) is a multi-disciplinary body of experts that provides evidence-based recommendations on immunizations to policy-makers to assist them in making immunization policy and program decisions. NITAGs faced challenges in making evidence-based recommendations for COVID-19 vaccines during the COVID-19 pandemic due to the new vaccine products available in a short time period and limited available data on vaccine effectiveness and vaccine safety. The authors reviewed the process used by the NITAG in the Federation of Bosnia and Herzegovina, called the expert body, to develop COVID-19 vaccine recommendations. The article reviews the evidence that was considered by the expert body when developing 23 recommendations on COVID-19 vaccination and describes the challenges and successes faced by the body. The expert body recommendations led to the successful roll-out of COVID-19 vaccines and provided guidance for COVID-19 vaccination during the pandemic. The expert body plans to improve its work and procedures for developing routine immunization recommendations with the support of the WHO Regional Office for Europe.