Non-Communicable Disease and Healthcare System Developments
LDL Cholesterol Targeting in Secondary Prevention: New Randomised Evidence
The Ez-PAVE trial, published in the New England Journal of Medicine on 28 March 2026, provides the first adequately powered randomised evidence directly comparing intensive versus conventional LDL cholesterol targets in patients with established atherosclerotic cardiovascular disease (ASCVD). Conducted in South Korea, the open-label superiority trial enrolled 3,048 patients randomised 1:1 to a target LDL-C below 55 mg/dL (1.4 mmol/L) versus below 70 mg/dL (1.8 mmol/L). Over a median follow-up of three years, the composite primary endpoint—encompassing cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, any revascularisation, or hospitalisation for unstable angina—occurred in 100 patients (cumulative incidence 6.6%) in the intensive-targeting group versus 147 patients (9.7%) in the conventional group (hazard ratio 0.67; 95% CI 0.52–0.86; p = 0.002). This corresponds to a 33% relative risk reduction, achieved with a median attained LDL-C of 56 mg/dL in the intensive arm versus 66 mg/dL in the conventional arm—a notably modest absolute separation between groups that nonetheless translated into a clinically meaningful outcome difference. Safety profiles were comparable across arms, with the exception of a lower incidence of creatinine elevation in the intensive-targeting group.
The findings are directly relevant to the clinical recommendations already embedded in both the 2026 ACC/AHA and 2025 ESC/EAS dyslipidaemia guidelines, which endorse a target below 55 mg/dL for very-high-risk secondary prevention patients. Notably, Ez-PAVE provides prospective randomised confirmation for a threshold that had previously rested largely on observational and Mendelian randomisation data. For the Bulgarian context, where ASCVD mortality remains among the highest in the EU and LDL-C management at the primary care level is suboptimal, these results strengthen the case for systematic adoption of intensive lipid-lowering targets and greater use of combination pharmacotherapy—including PCSK9 inhibitors and ezetimibe—when high-intensity statin monotherapy is insufficient.
Severe Infections and Dementia Risk: A Prospective Multicohort Analysis
A large prospective observational study published in The Lancet examined whether the previously documented association between hospital-treated severe infections and subsequent dementia risk is explained by pre-existing frailty, comorbidities, or other age-related conditions. The primary analysis in the UK Biobank cohort (n = 435,957 with dementia follow-up; 23,860 with a record of severe infection during the five-year exposure window) demonstrated that adjustment for frailty using the Fried Frailty Scale produced negligible attenuation of the infection–dementia association (adjusted HR 1.54 before versus 1.49 after adjustment). The association remained significant even within the non-frail subgroup (adjusted HR 1.34; 95% CI 1.18–1.53), with pre-frail and frail participants showing a modestly higher corresponding HR (1.62; 95% CI 1.47–1.79). Results from the Whitehall II replication cohort were consistent in direction but less precise. These findings are epidemiologically important because they substantially reduce the plausibility of pure confounding by pre-existing vulnerability as the explanatory mechanism, and shift the burden of evidence towards a more direct biological pathway—potentially involving neuroinflammation, microglial activation, or vascular injury. The authors appropriately note that interventional research testing whether infection prevention or treatment reduces dementia incidence is now warranted. The public health implications are significant: infections that generate substantial hospitalisation rates—including influenza, pneumonia, and sepsis—may carry a longer-term neurocognitive burden beyond the acute episode.
Psychiatric Bed Capacity and Suicide Mortality in Sweden
A nationwide ecological study using data from 20 Swedish counties between 2015 and 2024 found that each 10-bed increase in psychiatric inpatient capacity per 100,000 inhabitants was associated with a 7.6% reduction in suicide mortality (rate ratio 0.924; 95% CI 0.881–0.969; p = 0.001) in within-county fixed-effects models. National psychiatric bed capacity in Sweden declined from approximately 30.6 to 24.2 beds per 100,000 inhabitants over this period; the authors estimate, assuming causal interpretation, that a return to 2015 capacity levels would correspond to approximately 83 fewer suicides annually in a population of 10.6 million. The study draws on robust administrative data and employs quasi-Poisson regression with fixed-effects and Bayesian decomposition models to distinguish within- from between-county variation—an important methodological feature that partially addresses the ecological confounding that limits simpler designs. While the study cannot establish causality and is subject to unmeasured confounding at the county level, its findings are directionally consistent with clinical and policy arguments for maintaining and expanding inpatient psychiatric capacity. The finding is directly relevant to ongoing debates across EU healthcare systems regarding resource rationalisation and mental health service reform.
Influenza Vaccine Composition for 2026/2027: EMA Recommendations
EMA’s Committee on Human Medicinal Products (CHMP) endorsed, at its March 2026 plenary meeting, the recommended composition of seasonal influenza vaccines for the 2026/2027 season. The recommendation marks the formal transition from quadrivalent to trivalent formulations, reflecting the global absence of B/Yamagata lineage viruses in circulation since March 2020. For egg-based and live-attenuated vaccines, the recommended strains are: an A/Missouri/11/2025 (H1N1)pdm09-like virus; an A/Darwin/1454/2025 (H3N2)-like virus; and a B/Tokyo/EIS13-175/2025 (B/Victoria lineage)-like virus. Cell-based vaccine manufacturers are recommended to use A/Missouri/11/2025 (H1N1)pdm09-like virus; A/Darwin/1415/2025 (H3N2)-like virus; and B/Pennsylvania/14/2025 (B/Victoria lineage)-like virus. In markets where the transition to trivalent vaccines has not been finalised, manufacturers of inactivated quadrivalent products may include B/Phuket/3073/2013 (B/Yamagata lineage) in line with previous WHO guidance. Marketing authorisation holders are expected to submit variation applications for centrally authorised products by 15 June 2026. The annual renewal of strain composition reflects the ongoing antigenic evolution of circulating influenza viruses and underscores the necessity of season-specific vaccination, particularly for older adults and individuals with underlying conditions who bear the greatest burden of influenza-associated morbidity.
Infectious Diseases: Global Perspective
Respiratory and Droplet Transmission
Avian Influenza A(H5N1): New Human Case in Cambodia
On 31 March 2026, the Cambodian Ministry of Health confirmed a new human case of avian influenza A(H5N1) infection in a child under five years of age from Banteay Ampil District in Oddar Meanchey province. Epidemiological investigation identified exposure to sick and dead poultry in both the household and surrounding village as the probable source; no additional cases were detected among close contacts, who received antiviral prophylaxis (oseltamivir) as a precautionary measure. This represents Cambodia’s third confirmed human A(H5N1) case of 2026—the previous case, involving an adult woman, was reported on 15 March 2026. Information on the viral clade has not been published; clade 2.3.2.1e has historically been the predominant circulating strain in Cambodia and in recent human cases in the country. Since 2003, Cambodia has accumulated 93 cases, including 52 deaths (case fatality rate 56%)—the highest nationally reported CFR among the major endemic countries.
Globally, the cumulative total since 2003 stands at 997 confirmed human cases of A(H5N1), including 477 deaths (CFR: 48%), spread across 25 countries. To date, no sustained human-to-human transmission has been detected. ECDC’s risk assessment remains unchanged: the overall risk for the general EU/EEA population is considered low, with direct contact with infected or dead poultry or a contaminated environment identified as the primary route of exposure. The occurrence of cases in young children with backyard poultry exposure underlines the importance of personal protective measures and awareness campaigns in affected settings.
Fecal-Oral Transmission
Cholera
Since 25 February 2026 and as of 30 March 2026, 17,723 new cholera cases, including 212 new deaths, have been reported worldwide. The five countries reporting the most cases in this period are Afghanistan (7,758), the Democratic Republic of the Congo (5,775), Mozambique (2,496), South Sudan (455), and Somalia (386). Notably, this period’s total is substantially lower than the previous reporting cycle (28 January–25 February 2026), which registered 24,009 new cases and 275 deaths—a decline of 26% in case numbers and 23% in deaths. The year-to-date comparison is also instructive: since 1 January 2026 and as of 30 March 2026, 44,602 cases and 496 deaths have been reported worldwide; the corresponding figures for the same period in 2025 were 95,191 cases and 1,188 deaths—a reduction of more than 50% year-over-year, suggesting a meaningful overall decline in global cholera burden in 2026 relative to the prior year.
The Democratic Republic of the Congo remains the country with the highest absolute mortality: 176 of the 212 new deaths in the reporting period occurred in the DRC. Mozambique, which reported only 64 cases in the same period of 2025, has accumulated 5,659 cases and 57 deaths in 2026 to date, indicating an active and severe outbreak context. South Sudan has reported 455 cases in 2026, compared with 25,179 in the same period of 2025—a dramatic decline that, if real, would represent a major public health achievement, though interpretation requires caution given variable reporting completeness. Cholera cases have continued to be reported in Africa, Asia, the Middle East, and the Americas; although the risk to travellers visiting affected countries remains low, sporadic importation to the EU/EEA is possible.
Infectious Diseases: European Union / European Economic Area
Bloodborne Transmission
Integrase Inhibitor-Resistant HIV-1: Multi-Country Signal
The most operationally significant EU/EEA signal in Week 14 is the detection and characterisation of transmitted integrase strand transfer inhibitor (INSTI)-resistant HIV-1 across multiple member states, documented in an ECDC special assessment. As of March 2026, 33 treatment-naive individuals from Belgium, Denmark, France, Greece, Hungary, Lithuania, Luxembourg, and the Netherlands have been reported as having been diagnosed between 2014 and 2025 with HIV-1 carrying high-level or major resistance to the INSTI drug class. Ireland, Norway, Romania, and Spain reported zero such cases. In the countries reporting cases, all individuals were treatment-naive, and some carried additional nucleoside and non-nucleoside reverse transcriptase inhibitor (NRTI/NNRTI) resistance.
The public health significance of this signal lies not in its current scale—the number of cases remains very few relative to the total number of people newly diagnosed with HIV during the reporting period, and there is no current evidence of widespread INSTI-resistant HIV transmission in the EU/EEA—but in its implications for both treatment and prevention. INSTIs, including dolutegravir, bictegravir, and cabotegravir, are now the recommended backbone of first-line antiretroviral therapy in all major international guidelines, and long-acting injectable cabotegravir is increasingly used for HIV pre-exposure prophylaxis (PrEP). The emergence and transmission of INSTI resistance may have significant implications for both treatment effectiveness and prevention strategies, including potential cross-resistance with the commonly used INSTI dolutegravir.
The epidemiological profile of the reported cases illustrates the complexity of the signal. In the Netherlands, two unlinked treatment-naive patients were identified in autumn 2025—one heterosexual Dutch man with no reported sexual partners since 2022 (carrying G140S and Q148H integrase mutations), and one bisexual man from South America with NNRTI resistance plus E138K and Q148K integrase mutations. Phylogenetic analysis confirmed the absence of a molecular link between the two, indicating independent acquisition. France reported 11 cases with major INSTI resistance mutations since 2014 through systematic surveillance of primary HIV infections, with second-generation INSTI-resistance mutations (including R263K, E138K/T, and S230R) distributed across multiple years. Lithuania reported two patients diagnosed in 2024 with high-level resistance to all four available INSTIs, both also carrying NRTI resistance. The absence of epidemiological or molecular linkage across country reports suggests these represent dispersed transmission events rather than a defined cluster; however, the pattern of findings across geographically disparate countries and over a ten-year window warrants continued systematic surveillance.
ECDC recommends that clinicians order genotypic resistance testing at the time of HIV diagnosis and prior to ART initiation, consistent with EACS guidelines. EU/EEA countries are encouraged to report unusual patterns of INSTI resistance via EpiPulse to enable early detection of emerging transmission networks.
SARS-CoV-2 Variant Classification
Since the last update on 27 February 2026, and as of 27 March 2026, no changes have been made to ECDC variant classifications for variants of concern (VOC), variants of interest (VOI), variants under monitoring (VUM), or de-escalated variants. Variant proportions available from a single EU/EEA reporting country for weeks 10–11 of 2026 indicate the predominance of BA.3.2 (VUM) at 30%, with NB.1.8.1 (VUM) and XFG (VUM) each at 10%, and BA.2.86 (VOI) at 0.0%. ECDC notes that low SARS-CoV-2 transmission, reduced reporting, and declining sentinel testing volumes across the EU/EEA significantly limit the accuracy of variant proportion estimates; data from a single country cannot be considered representative of the broader regional situation. None of the currently circulating sublineages is assessed to be associated with increased infection severity or reduced vaccine effectiveness against severe disease compared with previously circulating variants, though older adults and immunocompromised individuals retain elevated risk.
Infectious Diseases: Bulgaria
Respiratory and Droplet Transmission
Measles — Outbreak Signal in Gabrovo District
The most urgent national epidemiological development in Week 14 is a large measles cluster in Gabrovo district, where 35 new cases were registered in a single week—by far the largest district-level measles report of 2026 in Bulgaria. Additional cases were reported from Kyustendil (2) and Pleven (6), bringing the national weekly total to 44 confirmed and probable cases. Measles, caused by a negative-sense single-stranded RNA paramyxovirus transmitted via respiratory droplets and aerosols, requires sustained population immunity above 95% (two-dose measles-mumps-rubella, MMR) to interrupt transmission. Bulgaria has experienced periodic measles resurgences attributable to accumulating susceptible cohorts, particularly in communities with historically suboptimal vaccine coverage. In the context of the ongoing international measles situation—including active outbreaks in Latvia, the United States, Mexico, and multiple other countries—the Gabrovo cluster underscores the national vulnerability to importation-seeded transmission in under-vaccinated communities.
Varicella
Varicella activity declined in Week 14, with 661 cases registered nationally compared with 784 in Week 13—a decrease of 123 cases (−16% week-over-week). The geographic distribution remained broad, with Sofia-grad contributing the largest share (163 cases), followed by Blagoevgrad (57), V. Tarnovo (50), Varna (50), and Plovdiv (51), with cases reported in all districts. The year-to-date total of 8,521 cases is 3% below the 8,782 registered in the same period of 2025, indicating that the 2026 varicella season as a whole remains marginally below the prior year’s baseline. The weekly decline, while potentially signalling a downward inflection, must be interpreted cautiously given the historical variability in varicella reporting; single-week decreases have been followed by rebounds in previous years and in earlier 2026 weeks. The case classification structure for Week 14—83 possible, 512 probable, 66 confirmed—reflects the predominantly clinical diagnosis basis on which varicella is reported in Bulgarian sentinel surveillance.
Scarlet Fever
Scarlet fever notifications declined substantially in Week 14, with 80 cases registered compared with 99 in Week 13 (−19 cases, −19% week-over-week). Geographically, Sofia-grad reported the highest single-district burden (17 cases), followed by Varna (16), Blagoevgrad (6), and Plovdiv (9). The year-to-date total of 1,067 cases represents a 25% deficit relative to the 1,425 cases registered in the same period of 2025, suggesting that despite period-specific fluctuations, the 2026 scarlet fever season has been notably less intense than the prior year overall. Scarlet fever is caused by Streptococcus pyogenes (group A streptococcus) producing erythrogenic toxin, and occurs predominantly in school-aged children; the week-over-week decline likely reflects both seasonal waning as spring temperatures rise and the approach of school holiday periods that interrupt institutional transmission chains.
Fecal-Oral Transmission
Gastroenteritis and Enterocolitis
A total of 181 cases of gastroenteritis and enterocolitis were reported in Week 14, compared with 189 in Week 13—a marginal decrease of 8 cases (−4% week-over-week). The case mix comprised 72 possible, 102 probable, and 7 confirmed cases. Geographically, Plovdiv (30), Sofia-grad (28), Varna (29), and Kardzhali (13) accounted for the largest district contributions. The year-to-date cumulative total of 1,972 cases exceeds the 1,926 cases registered in the same period of 2025 by 46 cases (+2.4%)—a deviation that does not meet the threshold for inclusion under the standard inclusion criteria, and is noted here solely to provide year-to-date context for the overall enteric disease burden.
Campylobacteriosis
Nine confirmed cases of campylobacteriosis were recorded in Week 14, one more than in Week 13 (+11% week-over-week). The year-to-date cumulative total of 143 cases stands against 54 cases in the same period of 2025—a 165% year-over-year excess that has been consistent and widening across all fourteen weeks of 2026. Campylobacter spp. are the most commonly reported bacterial cause of gastroenteritis in the EU/EEA, primarily transmitted through consumption of undercooked poultry, unpasteurised dairy products, or contaminated water. The sustained Bulgarian surplus, now extending beyond a seasonal or single-source explanation in its chronological persistence, warrants a coordinated investigation involving food safety authorities with source-attribution analysis focused on poultry supply chains.
Rotavirus Gastroenteritis
Rotavirus gastroenteritis increased in Week 14, with 23 confirmed cases registered compared with 18 in Week 13 (+5 cases, +28% week-over-week). The year-to-date total of 211 cases is 24% below the 278 cases registered in the same period of 2025, reflecting an overall milder rotavirus season in 2026. Rotavirus is the leading cause of severe dehydrating gastroenteritis in young children globally; the predominance of early childhood cases and the seasonal peak in winter and early spring months is consistent with Bulgaria’s current epidemiological profile. The week-over-week increase is notable but does not significantly alter the overall pattern of a subdued 2026 season.
Contact and Sexual Transmission
The pattern of sexually transmitted infections (STIs) in Bulgaria in 2026 continues to demonstrate marked year-over-year surpluses in gonorrhea and urogenital chlamydial infection—a trend sustained across all reporting weeks of the year.
Gonorrhea
One confirmed case of gonorrhea was registered in Week 14, a decrease of 7 from Week 13 (8 cases, −88% week-over-week). While this single-week figure represents the lowest weekly count of 2026 to date, the year-to-date cumulative total of 67 cases against 18 cases in the same period of 2025 constitutes a 272% year-over-year increase. The sustained magnitude of this excess, now spanning fourteen weeks without abatement at the cumulative level, strongly suggests a genuine increase in transmission intensity or a structural shift in case ascertainment, rather than a reporting artefact. The clinical and public health significance of Neisseria gonorrhoeae is amplified by internationally documented antimicrobial resistance trends, including the emergence of extensively drug-resistant strains.
Urogenital Chlamydial Infection
Eleven confirmed cases of urogenital chlamydial infection were registered in Week 14, an increase of 8 from Week 13 (+267% week-over-week—from 3 to 11 cases). The year-to-date total of 96 cases contrasts with 43 cases in the same period of 2025, representing a 123% year-over-year increase. The week-over-week jump, while numerically prominent on a percentage basis due to the low absolute numbers in Week 13, is consistent with the overall trajectory of expanding chlamydial reporting in 2026. Chlamydia trachomatis is predominantly asymptomatic, particularly in women, which complicates direct comparison of weekly counts and makes cumulative trends a more reliable epidemiological indicator.
Syphilis
Six confirmed cases of syphilis were reported in Week 14, down two from Week 13 (−25% week-over-week). The year-to-date total of 93 cases is 16% below the 111 cases registered in the same period of 2025, maintaining the pattern observed in prior weeks of a modest year-over-year deficit in syphilis notifications. Two confirmed cases of congenital and neonatal syphilis were reported in Week 14—the first such weekly count in 2026—bringing the year-to-date total to 8 cases compared with 9 cases in the same period of 2025. Congenital syphilis is a sentinel indicator of the quality of antenatal screening and treatment, and any weekly occurrence warrants attention given its complete preventability through timely antenatal serological testing and treatment of maternal infection.
Vector-Borne Transmission
Lyme Borreliosis
Three confirmed cases of Lyme borreliosis were registered in Week 14, an increase of 2 from Week 13 (+200% week-over-week on a base of 1 case). The year-to-date cumulative total of 43 cases is 12% below the 49 cases in the same period of 2025. The week-over-week increase, while proportionally large, reflects the expected onset of the primary tick activity season in Bulgaria, consistent with April’s warming temperatures and increasing Ixodes ricinus activity. One probable case of Mediterranean spotted fever (Marseilles fever), caused by Rickettsia conorii and transmitted by Rhipicephalus ticks, was also registered in Week 14—the first case of 2026, against zero cases in the corresponding period of 2025. Although a single case does not warrant an epidemiological alert in isolation, the seasonal concordance with tick emergence and the prior year’s absence of cases during this period warrants clinician awareness. Additionally, 2 confirmed cases of Q fever (Coxiella burnetii) were registered in Week 14, both new from Week 13. The year-to-date total of 10 cases is below the 14 cases registered in the same period of 2025.