Non-Communicable Disease and Healthcare System Developments
EMA Vaccine Confidence Advisory Group
On 29 April 2026, the European Medicines Agency formally launched a new advisory group on vaccine confidence, convening for the first time with a membership of over 20 high-level European and international experts drawn from academia, healthcare professional societies, medical organisations, patient advocacy groups, and public health institutions. The group will meet quarterly and is tasked with advising the Agency on the evolving landscape of vaccine hesitancy, contributing to EMA’s outreach and communication strategy, and amplifying science-based public health messaging to healthcare professionals and the broader public. This development is part of EMA’s broader Vaccine Outreach Strategy and follows collaborative initiatives with EU medical academies including the development of the Vaccine Essentials communication tool in partnership with the European Academy of Paediatrics. The establishment of this group is particularly timely: measles is currently in active outbreak transmission in the United States, Mexico, Canada, and multiple EU/EEA countries, with Bulgarian national surveillance now detecting a significant weekly case burden (see Section 4), making institutional support for vaccination confidence a matter of immediate public health relevance.
Sex-Based Disparities in TAVI Outcomes: Ten-Year US Medicare Cohort
A large nationwide cohort study published in JAMA Cardiology on 6 May 2026 analysed sex-based patterns and long-term outcomes of transcatheter aortic valve implantation (TAVI) among 314,123 US Medicare fee-for-service beneficiaries treated between 2013 and 2022. The study found that the proportion of women undergoing TAVI declined progressively from 47.6% in 2013 to 43.6% in 2022, raising questions regarding referral equity for symptomatic aortic valve disease in women. Despite substantial improvements in periprocedural safety for both sexes over the decade, women consistently exhibited higher early procedural risk: periprocedural mortality of 2.5% versus 2.2% in men (adjusted OR 1.20; 95% CI 1.14–1.26), vascular complications of 5.8% versus 3.6% (AOR 1.65), and major or life-threatening bleeding of 10.4% versus 6.8% (AOR 1.67). Women required permanent pacemaker implantation less frequently (16.9% vs 20.0%; AOR 0.81). Over longer follow-up, women demonstrated modestly but significantly better all-cause survival (adjusted HR 0.92; 95% CI 0.91–0.93), though with higher risks of heart failure hospitalisation, stroke, and bleeding events compared with men. The findings highlight a persisting paradox: women bear disproportionate procedural risk while achieving marginally better long-term survival, and their declining representation in the treated population suggests that factors beyond clinical severity—including referral practices and diagnostic delay—may contribute to inequitable access. These data are relevant for cardiology practice and cardiovascular health policy in Bulgaria, where cardiac interventional capacity is concentrated in a limited number of tertiary centres.
Prenatal Benzodiazepine Exposure and Childhood Psychiatric Outcomes
A population-based cohort study published in The BMJ on 29 April 2026 examined the association between prenatal exposure to benzodiazepines or Z-hypnotics and psychiatric disorders in children, using the National Health Information Database of South Korea and following 3,809,949 liveborn children from 2010 to 2023. Of these, 94,482 (2.5%) were exposed to benzodiazepines or Z-hypnotics during pregnancy. While unadjusted analyses and comparison with unexposed pregnancies suggested an elevated risk, the critical methodological contribution of the study is its sibling-controlled analysis, designed to account for shared familial and genetic confounding. In this design, the association with overall psychiatric disorders was fully attenuated (hazard ratio 0.99; 95% CI 0.94–1.04), with no increased risk observed for any of 12 specific psychiatric outcomes. Modest point estimate elevations were noted in subgroups with exposure during the second half of pregnancy and with 30 or more days of Z-hypnotic use, but confidence intervals were wide and included the null. The study provides important reassurance for clinical practice: benzodiazepines and Z-hypnotics are occasionally necessary during pregnancy for management of severe anxiety and sleep disorders, and the finding that familial confounding appears to explain the apparent association in prior studies meaningfully recalibrates the evidence base for prescribing decisions. The authors appropriately caution that uncertainty remains for specific high-dose or late-pregnancy exposures.
Infectious Diseases: Global Perspective
Respiratory and Droplet Transmission
Avian Influenza A(H5N1)
On 29 April 2026, WHO reported a fatal human case of avian influenza A(H5N1) infection in a child from Chattogram Division, Bangladesh, with disease onset on 21 January 2026. The child had no documented comorbidities. Illness onset was followed by hospitalisation on 28 January and ICU admission on 31 January; the child died on 1 February. A nasopharyngeal swab collected on 29 January tested positive for influenza A(H5) by real-time RT-PCR at the National Influenza Centre and was subsequently characterised by whole-genome sequencing as clade 2.3.2.1a (Gs/GD lineage), consistent with strains circulating in Bangladeshi poultry since 2011. Epidemiological investigation identified the source as household poultry—two ducks and one chicken reportedly died shortly before illness onset, and environmental samples from community ducks and household frozen chicken meat tested positive for A(H5) by RT-PCR. This is the first confirmed human A(H5) case in Bangladesh in 2026; four cases were reported in the country in 2025. Samples from symptomatic close contacts tested negative.
Since 2003, a cumulative total of 998 confirmed human A(H5N1) cases have been reported across 25 countries, with 478 deaths (case fatality ratio: 48%). No sustained human-to-human transmission has been detected. ECDC’s risk assessment for the general population in the EU/EEA remains unchanged at low, reflecting the sporadic and zoonotic character of human infections with current circulating strains. The case underlines the persistent risk of unprotected contact with backyard poultry in regions where A(H5N1) circulates endemically in birds, and reinforces the importance of personal protective equipment in surveillance and outbreak investigation activities.
Zoonotic and Contact Transmission
Hantavirus Cluster Linked to Cruise Ship Travel
The most significant emerging global signal of the reporting period is a cluster of severe respiratory illness aboard a Dutch-flagged cruise ship, reported to WHO on 2 May 2026 and generating continued international response activity as of 4 May. The vessel departed Ushuaia, Argentina, on 1 April 2026 carrying 147 individuals—88 passengers and 59 crew members of 23 nationalities—and followed an itinerary across the South Atlantic encompassing mainland Antarctica, South Georgia, Nightingale Island, Tristan da Cunha, Saint Helena, and Ascension Island. As of 4 May, seven cases (two laboratory-confirmed and five suspected) have been identified, including three deaths, one patient hospitalised in intensive care, and three individuals with mild ongoing symptoms. The vessel is currently moored off the coast of Cabo Verde.
Hantavirus cardiopulmonary syndrome (HCPS) is caused by hantaviruses of the genus Orthohantavirus (family Hantaviridae). Human infection is primarily acquired through inhalation of aerosolised excreta—urine, faeces, or saliva—from infected rodents, or through direct contact with contaminated surfaces. Sylvatic rodents serve as natural reservoirs, with different species carrying distinct viral strains across geographic regions. In South America, Orthohantavirus andesense (Andes virus) is the predominant cause of HCPS, and this species is of particular epidemiological concern because, unlike other hantaviruses, it has been documented in previous outbreaks to permit limited human-to-human transmission in settings of close and prolonged contact, including secondary cases in household contacts and healthcare workers, though such events remain rare.
The clinical syndrome is characterised by a prodromal phase of fever, headache, myalgia, and gastrointestinal symptoms lasting two to eight days, followed by abrupt-onset respiratory distress, hypotension, and potential progression to acute respiratory distress syndrome (ARDS) and cardiogenic shock. Incubation ranges from one to eight weeks, with most cases presenting two to four weeks after exposure. Case fatality ratios in the Americas range up to 50%, substantially higher than the less-than-1% to 15% seen with hantavirus haemorrhagic fever with renal syndrome (HFRS) in Europe and Asia. No specific antivirals or licensed vaccines exist; management is supportive and survival is improved by early ICU-level care.
Illness onset in the cluster ranged from 6 to 28 April. Two of the confirmed cases had documented travel in South America, including Argentina, before boarding. Case 1 (adult male) developed symptoms on 6 April, rapidly progressed to respiratory distress, and died aboard on 11 April; no samples were collected antemortem. Case 2 (adult female, close contact of Case 1) went ashore at Saint Helena on 24 April with gastrointestinal symptoms, deteriorated during an evacuation flight, and died upon arrival at a Johannesburg emergency department on 26 April; PCR confirmed hantavirus on 4 May. Case 3 (adult male), presenting with pneumonia on 24 April, was medically evacuated to South Africa and is currently in ICU; PCR on an extensive respiratory pathogen panel was negative for all other pathogens, with hantavirus confirmed on 2 May. Case 4 (adult female) died on 2 May following symptom onset on 28 April. Laboratory confirmation has been conducted at the National Institute for Communicable Diseases (NICD) of South Africa; sequencing and metagenomics are ongoing. Additional specimens are being transferred to the Institut Pasteur de Dakar.
Public health response involves the national IHR Focal Points of Cabo Verde, the Netherlands, Spain, South Africa, and the United Kingdom, with WHO having activated three-level coordination. Contact tracing among flight co-passengers of Case 2 has been initiated. WHO currently assesses the risk to the global population as low; the absence of sustained community transmission, the remote travel history, and the epidemiological pattern most consistent with zoonotic acquisition in South America support this assessment, though the potential for Andes virus human-to-human transmission warrants ongoing clinical vigilance aboard the vessel and at receiving healthcare facilities.
Fecal-Oral Transmission
Cholera
The ECDC monthly cholera update for the period 30 March to 28 April 2026 documents 20,028 new cases worldwide, including 272 deaths, across 13 countries in Africa, Asia, the Middle East, and Myanmar. Since 1 January 2026 and as of 28 April, cumulative global case counts stand at 65,153 including 768 deaths—a figure notably lower than the 96,282 cases and 1,192 deaths recorded in the comparable period of 2025, suggesting a modest reduction in global cholera burden compared with the previous year. The five countries with the highest case counts are Afghanistan (7,446), the Democratic Republic of the Congo (6,146), Yemen (1,564), Malawi (1,486), and Mozambique (944). The DRC continues to account for the highest number of recent deaths, with 216 fatalities in the most recent reporting period—a disproportionate burden reflecting the ongoing humanitarian and health system crisis in that country.
Cholera is caused by Vibrio cholerae O1 and O139 serogroups and is transmitted primarily via contaminated water and food. The disease is characterised by profuse watery diarrhoea, rapid dehydration, and electrolyte imbalance, with case fatality ratios of less than 1% with adequate oral or intravenous rehydration, rising to 25–50% in untreated cases in resource-constrained settings. The risk of cholera infection in travellers to affected countries remains low, and the risk of locally acquired cases in the EU/EEA remains very low based on the epidemiological history; 16 imported cases were reported in EU/EEA countries in 2024. No cholera cases have been reported in Bulgaria in 2026.
Vector-Borne Transmission
Chikungunya — French Guiana
Since January 2026, French Guiana has reported 143 confirmed autochthonous cases of chikungunya virus disease, with a notable acceleration in Week 16 when 33 cases were identified—more than double the 15 cases of the preceding week (+120%). The Littoral ouest sector, located on the western border with Suriname, accounts for 80% of cases (115 of 143) and was formally declared to be in the epidemic phase on 23 April 2026, the highest level of the surveillance classification framework. The identified strain belongs to the ECSA genotype without the E1-A226V mutation, showing close genetic proximity to sequences from Cuba and Brazil. Suriname, which shares the relevant border, reported 2,579 cases between January and mid-March 2026. The 2014–2015 chikungunya outbreak in French Guiana generated over 16,000 suspected cases and produced an estimated population seroprevalence of 20% by 2017, indicating the potential scale of the current event if transmission is sustained through the ongoing rainy season (January–July). ECDC currently assesses infection risk for travellers to French Guiana as low and the risk of onward transmission in mainland Europe as very low, given unfavourable environmental conditions for Aedes mosquito activity in Europe at this time of year.
Infectious Diseases: European Union / European Economic Area
Respiratory Transmission
SARS-CoV-2 Variant Surveillance
As of 24 April 2026, no changes have been made to ECDC’s SARS-CoV-2 variant classifications since the previous update of 27 March 2026; there remain no variants of concern (VOC) currently designated. Based on available genomic data from weeks 14–15 of 2026—derived from a single reporting EU/EEA country and therefore reflecting a very limited and potentially non-representative sample—BA.3.2 (variant under monitoring, VUM) accounts for 80% of sequenced specimens, with XFG (VUM) at 12% and NB.1.8.1 (VUM) at 4%. The interpretive limitation introduced by single-country sequencing data is explicitly acknowledged by ECDC and should be borne in mind: this distribution cannot be generalised to EU/EEA-wide circulating variants with confidence. Ongoing low SARS-CoV-2 transmission, reduced clinical testing, and diminishing reporting volumes across the region collectively constrain variant surveillance resolution at the European level. The variants currently classified as VOI or VUM are not associated with increased severity or reduced vaccine effectiveness against severe disease compared with previously circulating strains, though older adults, immunocompromised individuals, and those without prior infection history remain at elevated risk for severe outcomes and continued vaccination of high-risk groups is recommended.
Infectious Diseases: Bulgaria
Week 18, 27 April–3 May 2026. Data source: NCIPD operational weekly analysis and NCOZA regional district surveillance bulletin. Note: The NCOZA district-level breakdown and the NCIPD national analytical report operate on a one-week structural lag; measles cases appearing in the NCOZA Week 18 document are not reflected in the NCIPD analysis for the same week.
Respiratory and Droplet Transmission
Measles
The most significant epidemiological signal identified in Bulgarian national surveillance during Week 18 is a substantial measles case burden visible in the NCOZA regional breakdown. Forty-three measles cases were registered nationally in the week of 27 April–3 May 2026, with a strikingly concentrated geographic distribution: Pleven district accounts for 20 cases, Vratsa for 14, Lovech for 6, Varna for 2, and Sofia-grad for 1. The clustering across three contiguous or proximate districts in central and northwestern Bulgaria—Pleven, Vratsa, and Lovech—strongly suggests active local outbreak transmission rather than diffuse sporadic importation. This is the largest single-week measles count recorded in Bulgaria in 2026 to date and constitutes a high-consequence epidemiological event requiring urgent public health attention. Measles is a vaccine-preventable disease caused by a highly transmissible paramyxovirus (Morbillivirus hominis) with a basic reproduction number (R₀) of 12–18, among the highest of any known human pathogen; herd immunity requires sustained two-dose vaccination coverage exceeding 95%, a threshold that remains unmet in segments of the Bulgarian population. Clinical disease progresses from prodromal fever, coryza, conjunctivitis, and Koplik’s spots to a generalised maculopapular rash, with complications including otitis media, pneumonia, and encephalitis occurring in approximately 10–30% of cases in unvaccinated populations; subacute sclerosing panencephalitis (SSPE), a progressive fatal neurological complication, occurs years after primary infection. Vulnerable groups include unvaccinated children, immunocompromised individuals, and young adults who received only one MMR dose in early childhood. The current Bulgarian outbreak must be viewed within the wider European and global measles context: multi-country European outbreaks have been documented throughout 2025–2026, and the US outbreak (exceeding 1,000 cases as of March 2026) underscores the international resurgence driven by vaccination coverage gaps.
Scarlet Fever
Sixty-two cases of scarlet fever were registered in Week 18, a modest three-case increase from the 59 cases of Week 17 (+5%), insufficient to meet the 20% week-over-week threshold. The year-to-date total of 1,280 cases remains 28% below the 1,771 cases in the same period of 2025, indicating that the current season is substantially less intense than the prior year. Activity is distributed across multiple districts with no unusual concentration pattern.
Varicella
A total of 432 varicella cases were reported in Week 18, representing a 178-case decline from the 610 cases of Week 17—a 29% week-over-week reduction. This is the largest single-week decrease recorded in the 2026 varicella season and may mark the beginning of the seasonal decline following the peak activity observed in preceding weeks. Despite this fall, the current week’s count remains high in absolute terms and reflects ongoing transmission, particularly given the nationwide distribution across all districts (Sofia-grad: 80; Blagoevgrad: 54; Varna: 40; Plovdiv: 28; Rusé: 28; Shumen: 48; among others). The year-to-date total of 10,941 cases is essentially equivalent to the 11,057 cases in the same period of 2025 (−1%), consistent with a broadly stable varicella season without notable year-over-year change. In the absence of universal childhood varicella vaccination in Bulgaria, sustained seasonal transmission is expected throughout the spring term.
Fecal-Oral Transmission
Gastroenteritis and Enterocolitis
One hundred and thirty-eight cases of gastroenteritis and enterocolitis were registered in Week 18, a 30-case decline from the 168 cases of Week 17 (−18%). While this change falls just below the 20% reporting threshold, the declining trend over recent weeks is consistent with the post-Easter return to baseline activity, as cluster outbreaks associated with gatherings or food events typically subside following major public holidays. The year-to-date total of 2,630 cases is marginally above the 2,572 cases in the same period of 2025 (+2%), indicating no meaningful year-over-year signal. Cases are distributed across multiple districts without exceptional geographic concentration.
Campylobacteriosis
Nine confirmed cases of campylobacteriosis were reported in Week 18, representing a 10-case decline from the 19 cases of Week 17 (−53%). While the week-over-week change is substantial in relative terms, the absolute numbers are small and week-to-week fluctuation in campylobacteriosis is expected due to the sporadic nature of individual exposures. More significant is the persistent year-over-year excess: the year-to-date cumulative total of 189 cases is 128% above the 83 cases registered in the same period of 2025. This sustained and marked excess across eighteen weeks of 2026 represents a signal requiring coordinated investigation involving food safety authorities and microbiological reference laboratories, with attention to potential shifts in poultry supply chain contamination, changes in diagnostic testing uptake, or reporting system sensitivity.
Vector-Borne and Zoonotic Transmission
Mediterranean Spotted Fever (Marseille Fever)
One probable case of Mediterranean spotted fever (Rickettsia conorii infection, also referred to as Marseille fever or Mediterranean tick typhus) was registered in Week 18, representing the first reported case of the week—an increase of one from the zero cases of Week 17. This case signals the opening of the seasonal transmission window for tick-borne rickettsioses in Bulgaria. Rickettsia conorii is transmitted by Rhipicephalus sanguineus, the brown dog tick, and causes a febrile illness characterised by a triad of fever, maculopapular or petechial rash, and the pathognomonic eschar (tache noire) at the site of the tick bite. The condition responds well to doxycycline but may be fatal if unrecognised and untreated, particularly in immunocompromised individuals. The year-to-date total of 2 cases in 2026 is below the 7 cases recorded in the same period of 2025 (−71%), suggesting a currently low-intensity season, though the tick season will intensify through May and June.
Lyme Borreliosis
Three confirmed cases of Lyme borreliosis were registered in Week 18, with no week-over-week change from Week 17. The year-to-date total of 54 cases is 18% below the 66 cases reported in the same period of 2025, indicating that the current Lyme borreliosis season has not exceeded the prior-year level. The steady, low-level detection pattern observed across weeks of 2026 is consistent with baseline tick activity as the primary season approaches. With warmer temperatures expected through May, clinicians should maintain awareness of Lyme borreliosis and other tick-borne pathogens in patients presenting with compatible syndromes following outdoor activities.
Contact and Sexually Transmitted Infections
The STI surveillance pattern in Bulgaria continues to reflect the pronounced year-over-year increases that have been documented consistently since the beginning of 2026. The epidemiological significance of this sustained expansion warrants emphasis: the current trajectory suggests either a genuine increase in transmission at the population level, improved ascertainment through expanded testing, or—most likely—a combination of both.
Gonorrhea
Three confirmed cases of gonorrhea were reported in Week 18, a two-case decline from the five cases of Week 17 (−40%), representing fluctuation in small weekly numbers rather than a directional trend. The year-to-date cumulative total of 85 cases is 227% above the 26 cases recorded in the same period of 2025. Neisseria gonorrhoeae is of heightened public health concern internationally due to the emergence and geographic spread of extensively drug-resistant (XDR) strains, with the ECDC reporting treatment failures with extended-spectrum cephalosporins across multiple EU/EEA countries. Bulgarian national surveillance does not routinely link antimicrobial susceptibility testing to case notifications, which represents a critical surveillance gap for resistance monitoring and treatment guidance at the national level.
Urogenital Chlamydial Infection
Four confirmed cases of urogenital chlamydial infection were registered in Week 18, one more than the three cases of Week 17 (+33%), though again the absolute numbers are small. The year-to-date total of 115 cases is 156% above the 45 cases in the same period of 2025. Chlamydia trachomatis is the most commonly reported sexually transmitted pathogen across the EU/EEA and is characterised by a high rate of asymptomatic carriage—particularly in women—that facilitates transmission and complicates case ascertainment. The sustained year-over-year excess in Bulgaria may reflect both genuine transmission increases and improved laboratory detection capacity, but the public health implications are identical in either scenario: potential sequelae including pelvic inflammatory disease, ectopic pregnancy, tubal factor infertility, and neonatal conjunctivitis and pneumonia require attention to testing, treatment, and partner notification.
Syphilis
Five confirmed cases of syphilis were reported in Week 18, a three-case increase from the two cases of Week 17 (+150%). The year-to-date total of 124 cases is essentially equivalent to the 126 cases in the same period of 2025 (−2%), indicating that unlike gonorrhea and chlamydia, syphilis has not demonstrated comparable year-over-year growth. One confirmed case of congenital or infant syphilis was reported in Week 18, the first case of the current week. The year-to-date total of 14 congenital syphilis cases in 2026 exceeds the 12 cases in the same period of 2025 (+17%), continuing a trend that warrants attention given the complete preventability of congenital syphilis through antenatal serological screening and timely treatment of seropositive pregnant women.
HIV
Five confirmed new HIV cases were registered in Week 18, a two-case increase from the three cases of Week 17 (+67%). The year-to-date total of 81 confirmed cases is 25% below the 108 cases in the same period of 2025—a reduction that may reflect changes in testing access, reporting completeness, or genuine transmission dynamics, and should be interpreted cautiously without further investigation. HIV is transmitted primarily through sexual contact, shared injecting equipment, and vertical mother-to-child transmission. Late diagnosis, which remains a persistent problem in Bulgaria, substantially impairs both individual treatment outcomes and population-level transmission control.
Recommendations
National and regional public health authorities should treat the concentration of 43 measles cases across Pleven, Vratsa, and Lovech districts in Week 18 as evidence of active outbreak transmission requiring urgent response: rapid case investigation to characterise vaccination status of cases, contact tracing, ring vaccination of susceptible contacts, and enhanced active surveillance in the affected districts are the immediate priorities; national immunisation coverage data for these regions should be reviewed and any coverage deficits corrected.
Given the coincident launch of the EMA Vaccine Confidence Advisory Group and the ongoing measles resurgence in Bulgaria and across the EU/EEA, healthcare providers and public health communicators should proactively address vaccine hesitancy in communities with suboptimal MMR coverage, drawing on EMA’s Vaccine Essentials materials and collaborating with regional health inspection offices to identify and reach unvaccinated or under-vaccinated individuals.
The hantavirus cluster aboard the cruise ship currently moored off Cabo Verde should prompt clinical awareness at Bulgarian healthcare facilities: although the WHO global risk assessment is low, citizens returning from South American travel—particularly those who visited rural or wildlife-rich environments in Argentina or neighbouring countries—presenting with febrile illness progressing to respiratory distress should have hantavirus included in the differential diagnosis; clinicians should contact the National Reference Laboratory for consultation if clinical suspicion arises.
The sustained 59% year-over-year excess in acute viral hepatitis ABCDEN through Week 18 requires continued investigation; public health authorities should prioritise disaggregation of the aggregate ABCDEN category into serotype-specific streams, undertake retrospective case review with laboratory typing where biobanked specimens exist, and assess whether the excess is driven by a single serotype or represents broad-based hepatitis activity.
The 128% year-over-year excess in campylobacteriosis through Week 18 warrants formal source-attribution investigation coordinated between the public health and food safety systems, with focus on poultry supply chains, abattoir hygiene monitoring, and an assessment of any changes in laboratory testing practices that might explain part of the apparent increase.
The dramatic and sustained year-over-year surges in gonorrhea (+227%) and urogenital chlamydial infection (+156%) in 2026 necessitate evaluation of national STI testing capacity and treatment pathway adequacy; antimicrobial susceptibility testing should be integrated into gonorrhea case reporting to permit real-time resistance monitoring in line with ECDC recommendations.
Surveillance data are subject to reporting delays and may not reflect the true burden of disease. Case counts are provisional and may be revised. Risk assessments represent the situation at the time of writing and may change as new information becomes available. The NCOZA district-level breakdown and the NCIPD national analytical report operate on a one-week structural lag; consequently, some diseases—including measles, which is reported through NCOZA—may not appear in the NCIPD operational analysis for the same surveillance week.
Sources: WHO Disease Outbreak News — Hantavirus cruise ship cluster (4 May 2026); ECDC Communicable Disease Threats Report, Week 18, 25 April–1 May 2026; NCIPD Operational Weekly Analysis, Week 18, 27 April–3 May 2026; NCOZA Regional District Surveillance Bulletin, Week 18, 27 April–3 May 2026; Nicolas J et al., JAMA Cardiology, 6 May 2026; Cho Y et al., BMJ 2026;393:e088671 (29 April 2026); EMA press release, 29 April 2026.