Despite the availability of a safe and effective vaccination, uptake of human papillomavirus (HPV) vaccination remains low worldwide. We aimed to analyze the coverage of HPV immunization during the first year of the immunization program and the sociodemographic characteristics across different administrative units in Serbia and Montenegro. Coverage of HPV vaccination in Serbia for females aged 9–14 and 15–19 years was 5.5% and 5.9%, respectively. The coverage rate of immunization against HPV in Montenegro for girls aged 9–14 years was 22.1%. Within Serbia, only one administrative region (Moravica) had HPV immunization coverage in girls 9–19 years old above 10%, 11 districts had coverage from 5 to 10%, while 13 districts had coverage below 5%. As per Montenegro, two administrative units, Cetinje and Berane, reported the highest coverage, with 39% and 36.4% of vaccinated eligible girls, respectively. When we explored the coverage of HPV immunization among girls aged 9–19 years across different regions in Serbia, we observed that the level of coverage did not correlate with the number of pediatricians or with the population density. In Montenegro, we observed a similar situation. On the other hand, we noticed a statistically significant moderate negative correlation (r = −0.446; p = 0.026) between HPV immunization coverage and the percentage of illiterate women in the administrative units. Comparing the coverage between the two countries we found that the higher coverage in Montenegro corresponded with a smaller number of female populations aged 9–14 years, with higher average net monthly income, with smaller population density and smaller number of pediatricians, among divorced persons, and among those without formal education or incompletely primary education. Taking into account the experiences in Montenegro, increasing immunization coverage in Serbia could be achieved through a more vigorous educational campaign targeting schools, the general population, and healthcare workers as well as by additionally incentivizing those engaged in these activities.

Background/Objectives: Mumps remains a relevant vaccine-preventable disease globally, especially in settings where immunization coverage fluctuates or vaccine-induced immunity wanes. This study aimed to assess long-term trends in mumps incidence, vaccination coverage, clinical outcomes, and demographic characteristics in the Autonomous Province of Vojvodina (AP Vojvodina), Serbia, over a 47-year period. Methods: We conducted a retrospective observational study using surveillance data from the Institute of Public Health of Vojvodina. Analyses included annual mumps incidence rates (1978–2024), coverage with mumps-containing vaccines (MuCVs; 1986–2024), monthly case counts, and individual-level case data for the 1997–2024 period. Variables analyzed included age, month of notification, gender, vaccination status, presence of clinical complications, and the method used for case confirmation. Results: Following the introduction of MuCV in 1986, the mumps incidence markedly declined, with limited resurgences in 2000, 2009, and 2012. Between 1997 and 2024, a total of 1358 cases were reported, with 62.7% occurring in males. Over time, the age distribution shifted, with adolescents and young adults being increasingly affected during the later (2011–2024) observed period. In 2012, the highest age-specific incidence was observed among individuals aged 10–19 and 20–39 years (49.1 and 45.5 per 100,000, respectively). Vaccination coverage for both MuCV doses was suboptimal in several years. The proportion of unvaccinated cases decreased over time, while the proportion with unknown vaccination status increased. Mumps-related complications—such as orchitis, pancreatitis, and meningitis—were rare and predominantly affected unvaccinated individuals: 84.2% of orchitis, 40.0% of pancreatitis, and all meningitis cases. Only two pancreatitis cases (40.0%) were reported after one MMR dose, while fully vaccinated individuals (two doses) had one orchitis case (5.3%) and no other complications. Laboratory confirmation was applied more consistently from 2009 onward, with 49.6% of cases confirmed that year (58 out of 117), and, in several years after 2020, only laboratory-confirmed cases were reported, indicating improved diagnostic capacity. Conclusions: Despite substantial progress in controlling mumps, gaps in vaccine coverage, waning immunity, and incomplete vaccination records continue to pose a risk for mumps transmission. Strengthening routine immunization, ensuring high two-dose MuCV coverage, improving vaccination record keeping, and enhancing laboratory-based case confirmation are critical. Consideration should be given to booster doses in high-risk populations and to conducting a seroepidemiological study to estimate the susceptible population for mumps in AP Vojvodina.

Background: Despite ongoing global elimination efforts, measles remains a persistent public health threat. Methods: This retrospective observational study examines trends in crude measles incidence and vaccination coverage from 1948 to 2024 in the northern region of Serbia—Autonomous Province of Vojvodina (AP Vojvodina)—which accounts for 26.9% of the national population. This study further explores measles vaccination coverage across the province’s seven districts, along with the number of reported measles cases, age distribution, and vaccination status of affected individuals from 2000 to 2024. Data were obtained from official annual immunization records maintained by public health institutions within the framework of Serbia’s national mandatory immunization program. Results: A notable resurgence of measles occurred in Serbia during 2017–2018, following a decline in vaccination coverage. In AP Vojvodina, outbreaks were recorded in 2007, 2014–2015, and 2017–2018, predominantly affecting unvaccinated children and adults aged 20–39 years. Since 2019, the measles incidence has significantly declined. During the 2018 outbreak, the highest incidence was observed among children aged 1–4 years (40.6 per 100,000), followed by infants under 1 year (17.3 per 100,000) and adults aged 20–39 years (12.5 per 100,000). An analysis of the data from 2000 to 2024 revealed substantial age- and dose-related differences in measles incidence, particularly among unvaccinated individuals, those who had received one or two doses of a measles-containing vaccine (MCV), and those with unknown vaccination status. During the 2017–2018 epidemic, unvaccinated children under 1 year and those aged 1–4 years were the most affected. A marked increase in cases among single-dose recipients was noted in 2018, especially in adults aged 20–39 years (9.5%) and those ≥40 years (13.5%). A considerable proportion of measles cases in these age groups had unknown vaccination status: 33.1% among individuals aged 20–39 years and 18.2% among those aged ≥ 40 years. Epidemiological investigation linked the 2007 and 2014–2015 outbreaks in AP Vojvodina to importations from Bosnia and Herzegovina. No specific source was identified for the 2017–2018 outbreak, suggesting possible endemic transmission. Conclusions: These findings underscore the impact of fluctuating vaccination coverage on measles resurgence. Sustaining high two-dose MCV coverage, strengthening routine immunization programs, enhancing surveillance systems, and ensuring timely outbreak preparedness are critical measures for achieving effective measles control.

Pertussis continues to be a significant public health concern. We aimed to examine the epidemiological characteristics of pertussis in Vojvodina, which accounts for almost a third of Serbia’s population. Our aim was to determine the overall and age-specific incidence and mortality rates of pertussis in Vojvodina from 1948 to 2023, as well as the coverage of immunization against pertussis from 1960 to 2023. In the period 1948–2023, 42,259 cases of pertussis were reported. Following the introduction of the DTwP vaccine (1960) in Serbia, the reported incidence of pertussis began to decline. In 2001, for the first time since introduction of pertussis surveillance in Vojvodina, no pertussis cases were reported. Since 2012, the reported incidence of pertussis has once again increased, and peaked (41.1/100,000) in 2023, approaching the incidence rates recorded shortly after the introduction of DTwP vaccine. A shift in the age profile of pertussis from children aged 0–6 years to school-aged children (7–14 years) occurred between 2012 and 2023, when 48.3% of pertussis cases occurred in this age group. Although the incidence rates of pertussis among individuals aged 20 years and older were significantly lower than among younger age groups, there is evidence of an increasing trend in pertussis cases, particularly among those aged 40–49 years, since 2012. Based on the findings of this study, it is imperative to introduce additional booster doses of the aP vaccine for individuals aged 14 years, along with implementing maternal immunization strategies targeting women of childbearing age.

Background: Despite decades of high childhood vaccination coverage, pertussis has re-emerged in the Autonomous Province of Vojvodina (AP Vojvodina), Serbia. We aimed to describe the temporal, seasonal, and age-specific patterns of pertussis in AP Vojvodina and to analyze trends by vaccination status in order to highlight changes in epidemiology and potential gaps in vaccine-induced protection. Methods: We retrospectively analyzed 2796 pertussis cases reported between January 1997 and December 2024, examining temporal, seasonal, and age-specific trends, stratifying by vaccination status across four consecutive periods (1997–2003, 2004–2010, 2011–2017, and 2018–2024). Results: Throughout the 28-year period, after low and sporadic cases in the pre-2012 period, a dramatic rise was observed in 2014, 2017, and 2018, culminating in the highest annual number of reported cases in 2024 (1011 cases). Throughout this period, primary vaccination coverage with the DTwP/DTaP three-dose series ranged between 91% and 98%, while first booster coverage gradually declined from 98% in the early 2000s to 83% in 2024. Regarding seasonality, a sharp increase in cases began in 2012, peaking in November 2023 (>350 cases) and early 2024 (312 in January, 268 in February), with a seasonal shift from summer peaks in the 2011–2017 period to higher incidence rates during colder months more recently. Adolescents aged 10–14 years had the highest cumulative incidence (1149.4/100,000), followed by infants under 12 months (978.5/100,000), despite the latter representing fewer absolute cases. The proportion of pertussis in fully vaccinated individuals rose from 6.3% (1997–2003) to 49.7% (2018–2024). Conclusions: These findings suggest that booster immunization in adolescence and routine maternal vaccination during pregnancy could reduce transmission, particularly to infants. Enhanced surveillance and updated immunization policies are critical to mitigating future pertussis outbreaks.