Non-Communicable Disease and Healthcare System Developments
EMA CHMP April 2026 Recommendations
The European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) issued positive opinions on five new medicines at its April 2026 meeting, with several carrying substantial clinical relevance for European practice.
The most consequential recommendation from a neurological standpoint is the approval of tolebrutinib (Cenrifki, Sanofi Winthrop Industrie) for the treatment of non-relapsing secondary progressive multiple sclerosis (nrSPMS) in adults. Tolebrutinib is a covalent Bruton’s tyrosine kinase (BTK) inhibitor that acts centrally within the central nervous system, where it targets microglial and B-cell-mediated neuroinflammation—pathological processes that predominate in the progressive phase of MS and that are inadequately addressed by conventional disease-modifying therapies designed primarily against relapse biology. Non-relapsing SPMS represents a particularly unmet medical need: patients in this disease stage typically do not benefit from the immunomodulatory mechanisms underlying most currently approved MS therapies, and the approval of a BTK inhibitor in this indication marks a meaningful therapeutic advance. The indication is restricted to adults in whom the progressive phase is established and in whom relapses are absent or clinically non-contributory.
Onasemnogene abeparvovec (Itvisma, Novartis Europharm Limited), a gene therapy for 5q spinal muscular atrophy (SMA), received a positive opinion in what constitutes an update to the existing marketing authorisation for this product (previously approved as Zolgensma). The CHMP also recommended approval of plozasiran (Redemplo, Arrowhead Pharmaceuticals), an RNA interference therapeutic targeting apolipoprotein C-III for the treatment of familial chylomicronaemia syndrome (FCS)—a rare autosomal recessive lipid disorder characterised by severely elevated triglycerides and recurrent pancreatitis, for which no licensed pharmacological treatment has historically been available. Both Itvisma and Redemplo received orphan medicine designation, reflecting the rarity and severity of their respective indications.
Two additional positive opinions were issued for a ranibizumab biosimilar (Rexatilux) for neovascular age-related macular degeneration and related retinopathies, and a palbociclib generic (Palbociclib Viatris) for the treatment of breast cancer—the latter expanding access to CDK4/6 inhibitor therapy as patent protection for the originator product concludes.
Among the nine extensions of therapeutic indication recommended, the update to the Comirnaty (BioNTech/Pfizer) COVID-19 mRNA vaccine is of ongoing public health relevance, as successive strain adaptations of the authorised vaccine are regularly incorporated via these extension procedures. The CHMP declined to recommend an extension of Opdualag (nivolumab/relatlimab) to include advanced melanoma with PD-L1 levels ≥1%, though it agreed to incorporate the relevant clinical data into the product information to support clinical decision-making for patients with PD-L1 levels below 1%. Two applications were withdrawn: Viokat (diazoxide choline) for Prader-Willi syndrome, and a proposed expansion of Pluvicto (lutetium-177 vipivotide tetraxetan) to treat asymptomatic or minimally symptomatic PSMA-positive metastatic castration-resistant prostate cancer.
Infectious Diseases: Global Perspective
Respiratory and Droplet Transmission
Avian Influenza A(H5N1): Human Case in Cambodia
On 21 April 2026, Cambodia’s Ministry of Health confirmed a new human case of avian influenza A(H5N1) infection in a woman in her 60s from Romduol district, Svay Rieng province, representing the country’s fourth confirmed human case in 2026. The patient was hospitalised and receiving antiviral treatment; epidemiological investigation revealed contact with sick and dead poultry both in the household and in the surrounding village during the two weeks preceding illness onset (2–13 April 2026), consistent with the established route of zoonotic transmission via direct or close contact with infected birds, their secretions, or contaminated environments. Close contacts received oseltamivir prophylaxis, and health education campaigns were initiated in the affected villages.
Since 2003, Cambodia has reported 93 human cases of A(H5N1), including 52 deaths, yielding a country-specific case fatality rate of 56%—substantially above the global average of 48%, which is based on 477 deaths among 998 confirmed cases across 25 countries. No clade information has been reported for the recent Cambodian cases; clade 2.3.2.1e has historically circulated among birds in Cambodia and has been associated with prior human infections in the country. Current virological evidence continues to indicate that circulating A(H5N1) viruses retain characteristics consistent with avian-adapted viruses. No sustained human-to-human transmission has been detected globally. ECDC’s risk assessment for the general population in the EU/EEA remains low, though the concentration of recent severe human cases in Asia—particularly in children and adults with unprotected backyard poultry exposure—reinforces the importance of personal protective measures for anyone in direct contact with infected or suspect birds.
A parallel animal-health signal of direct relevance to the regional context was reported by Ukraine, which notified the WOAH on 21 April 2026 of the recurrence of highly pathogenic avian influenza A(H5N1) in non-poultry including wild birds—a finding that underscores ongoing viral circulation in the migratory flyways traversing Eastern Europe and the Black Sea basin.
Avian Influenza A(H9N2): Batch Report of Five Human Cases from China
The Hong Kong Centre for Health Protection reported five new human infections with avian influenza A(H9N2) in mainland China, with symptom onset between January and March 2026. Four of the five cases were children aged five years or younger from Guangdong, Jiangxi, and Yunnan provinces; the fifth was a 63-year-old man from the Guangxi Zhuang Autonomous Region. Information on exposure history and specific clinical outcomes has not been made publicly available. This batch reporting reflects a pattern consistent with prior H9N2 notifications from China, whereby cases with onset in earlier months are disclosed following laboratory confirmation and administrative review.
Globally, 201 human cases of H9N2, including two deaths, have been reported by 11 countries since 1998; since 2015, China alone has accounted for 159 of these cases. The case fatality rate of approximately 1% reflects a generally mild clinical syndrome, though severe outcomes occur in young children and those with comorbidities. No clusters indicative of human-to-human transmission have been documented, and the virus has not acquired sustained transmissibility in humans. ECDC classifies the current risk to human health in the EU/EEA as very low.
Fecal-Oral Transmission
Salmonella Bovismorbificans: Multicountry EU/EEA Outbreak
A multicountry outbreak of Salmonella Bovismorbificans has been detected, with approximately 50 genetically closely related confirmed cases identified across Ireland, Finland, and the United Kingdom between January and April 2026, involving exclusively adults with a predominance of females (71%). At least five cases have required hospitalisation. Outbreak investigations in all three countries converge on the consumption of sprouted seeds and microgreens as the common food exposure, and a dedicated RASFF notification (2026.3378) has been issued. Four additional EU/EEA countries have identified cases with closely related isolates from the same period, and a fifth country has observed an increase in this serotype, though food and travel exposure data are not yet available from these additional cases.
Salmonella Bovismorbificans is a relatively infrequent serotype in European surveillance and its emergence in a multicountry cluster centred on sprouted seeds is epidemiologically noteworthy. Sprouted seeds have been implicated in multiple previous EU-level foodborne outbreaks—most notably the 2011 E. coli O104:H4 outbreak across Germany and France—because the warm, humid germination environment supports bacterial amplification, and heat treatment is rarely applied to the final product. ECDC is monitoring the event through EpiPulse in collaboration with EFSA and the European Commission, and countries are encouraged to share epidemiological and microbiological data if linked cases are identified. The absence of travel history among confirmed cases supports domestic source exposure and underscores the public health importance of the ongoing food investigation.
Infectious Diseases: European Union / European Economic Area
Respiratory and Droplet Transmission
End-of-Season Respiratory Virus Situation
Respiratory virus activity across the EU/EEA has substantially resolved as of week 16, 2026, with influenza returning to inter-seasonal levels in almost all reporting countries. Test positivity for influenza in primary care settings stood at a pooled median of 1.8% (IQR 1.1–5%) in week 15, with 21 of 21 reporting countries at baseline or low intensity—a stark contrast to the elevated activity that characterised the winter months. In hospital settings, SARI-associated influenza positivity was 3% (IQR 4; 1.8–5.7%) across nine reporting countries. The geographic spread of influenza transmission was classified as sporadic in eight countries, local in four, and regional in five, with no country reporting widespread activity; four countries had no detected influenza activity. Influenza A was the predominant type throughout the season, with A(H3) accounting for 60% of subtyped viruses and the subclade 2a.3a.1(K) representing 90% of genotyped A(H3) specimens. A(H1)pdm09 comprised the remaining 40%, predominantly subclade 5a.2a.1(D.3.1).
RSV remained the principal contributor to respiratory virus activity in week 15, with a pooled primary-care test positivity of 5.5% (IQR 7.3; 2.6–11%) across 14 reporting countries and a hospital positivity of 10% (IQR 13; 5–17%) across nine countries. RSV-B accounted for 68% of subtyped primary-care specimens and 67% in hospital settings, consistent with the subtype distribution observed across the season. Although RSV activity is declining and the seasonal peak has passed, transmission remains moderate particularly among children aged 0–4 years and adults aged 60 years and above—the populations at highest risk for severe RSV disease. SARS-CoV-2 activity remained very low in all countries and age groups, with primary-care positivity at 1% (IQR 0; 0–1.4%) and hospital positivity at 1% (IQR 0.7; 0–1%).
Fecal-Oral Transmission
The Salmonella Bovismorbificans multicountry outbreak—described above in the global section—is fundamentally a European public health event, with its confirmed cases concentrated in Ireland, Finland, and the UK and additional related isolates identified in four further EU/EEA countries. Public health authorities in member states should maintain vigilance for cases of salmonellosis presenting in adults without documented travel history, particularly those with exposure to raw or sprouted plant products, and should consider microbiological typing to assess potential linkage to this outbreak cluster.
Infectious Diseases: Bulgaria
Respiratory and Droplet Transmission
Measles
The most significant epidemiological finding in Bulgarian national surveillance for Week 17 is the identification of 37 measles cases in the district-level breakdown from the National Centre for Public Health and Analyses (NCOZA/ZRZ), compared with zero cases visible in the operational analysis of the National Centre for Infectious and Parasitic Diseases (NCIPD). This discrepancy reflects the one-week structural lag that characterises the relationship between the two surveillance streams, and the 37 cases registered in the ZRZ report for the period 20–26 April 2026 should be interpreted as the current week’s district-level ascertainment. The geographic concentration is pronounced: Vratsa district accounts for 23 cases (62% of the national weekly total), followed by Pleven with 7 cases and Kyustendil with 6 cases, with a single case in Sofia-grad. This distribution—heavily centred in Vratsa—is consistent with an active local outbreak rather than dispersed importation events, though the epidemiological linkages between the clusters in different districts require investigation.
Measles (Morbillivirus hominis) is transmitted via the respiratory route with a basic reproduction number (R₀) of 12–18, among the highest of any known pathogen, rendering population immunity thresholds above 95% necessary to interrupt chains of transmission. The clinical syndrome—prodromal fever, coryza, conjunctivitis, and Koplik spots followed by a cephalocaudal maculopapular exanthem—is well characterised, but severe outcomes including pneumonia (the leading cause of measles mortality), encephalitis, and subacute sclerosing panencephalitis can occur, particularly in malnourished children, immunocompromised individuals, and adults. The occurrence of 37 cases in a single week is the largest weekly measles burden recorded in Bulgarian surveillance during 2026 and is contextualised by the dramatic global escalation of measles underway—with the United States exceeding 1,000 cases, Mexico registering tens of thousands, and ECDC reporting 173 cases across EU/EEA countries in January 2026 alone. The current Bulgarian event is of immediate public health concern and warrants expedited case investigation, contact tracing, identification of vaccination status, and assessment of whether the district clusters share epidemiological linkage or represent distinct introduction events.
Scarlet Fever
Scarlet fever registrations reached 59 cases in Week 17, representing an increase of 23 cases over the preceding week—a 64% week-over-week rise. This is a substantial single-week acceleration for a disease that had been tracking at moderate endemic levels through the preceding weeks of 2026. Scarlet fever is caused by Streptococcus pyogenes (group A streptococcus) elaborating pyrogenic exotoxins, predominantly affecting school-age children and presenting with acute pharyngitis, a characteristic sandpaper rash, and strawberry tongue; uncomplicated cases respond well to beta-lactam antibiotics, though rare severe manifestations including streptococcal toxic shock syndrome and invasive group A streptococcal disease warrant clinical vigilance. Of the 59 cases, 22 were classified as possible, 30 as probable, and 7 as confirmed, consistent with standard syndromic and laboratory-based case ascertainment practices. The year-to-date total of 1,218 cases is substantially below the 1,686 registered in the same period of 2025 (−28%), indicating that despite the current week’s spike, the 2026 scarlet fever season has not yet surpassed its prior-year baseline; however, the sharp Week 17 acceleration merits close monitoring. The geographic distribution from ZRZ data identifies Varna (12), Blagoevgrad (5), Plovdiv (5), and Sofia-grad (13) as principal foci, with cases distributed across most districts.
Fecal-Oral Transmission
Campylobacteriosis
Campylobacteriosis registered 19 confirmed cases in Week 17, an increase of 7 from the 12 cases in Week 16—a 58% week-over-week rise. This week’s figure continues a pattern of sustained and markedly elevated transmission: the cumulative 2026 total of 180 cases through Week 17 is 150% above the 72 cases registered in the same period of 2025. Campylobacter spp. are the most commonly identified bacterial cause of foodborne gastroenteritis in EU/EEA countries and are primarily acquired through consumption of undercooked poultry, contaminated water, or raw milk, with an incubation period of 2–5 days. The disease typically presents as self-limiting watery or bloody diarrhea with abdominal cramping and fever, though post-infectious complications—including reactive arthritis and Guillain-Barré syndrome—occur in a small proportion of cases. The scale of the 2026 excess in Bulgaria is not consistent with random surveillance variation and warrants coordinated food safety investigation targeting poultry supply chains, alongside assessment of potential changes in laboratory testing volume or diagnostic practice that could partly explain the observed increase.
Rotavirus Gastroenteritis
Rotavirus gastroenteritis surged to 30 confirmed cases in Week 17, compared with 16 in Week 16—an 88% week-over-week increase, representing the largest single-week count of 2026. This rise is noteworthy as it coincides with the period during which rotavirus transmission typically peaks in the spring months, though the Year 17 figure remains below the year-to-date comparison: 265 cases in 2026 versus 320 in the same period of 2025 (−17%). The geographic distribution from ZRZ data shows Sofia-grad (10) and Stara Zagora (6) as the principal contributors, with smaller numbers distributed nationally. Rotavirus infection is the leading cause of severe dehydrating gastroenteritis in young children globally and a significant cause of paediatric hospitalisation in countries without universal rotavirus vaccination, a category that includes Bulgaria. The current week’s rise warrants monitoring to determine whether this represents the seasonal peak or the beginning of a more sustained increase.
Typhoid Fever
A single confirmed case of typhoid fever (coremен тиф) was registered in Week 17—the first confirmed case reported in Bulgaria in 2026 to date. Salmonella Typhi, the causative agent, is primarily acquired through consumption of contaminated food or water, with an incubation period of 6–30 days. Typhoid fever presents with progressive fever, headache, relative bradycardia, and a characteristic rose-spot rash, and may be complicated by intestinal perforation, haemorrhage, and systemic dissemination. No confirmed cases were recorded in Bulgaria in the equivalent period of 2025, and the ZRZ data attribute this case to Varna district. Given the sporadic nature of typhoid in Bulgaria, characterisation of the exposure history—particularly any international travel, consumption of specific food items, or contact with a known case—is essential to determine whether this represents an imported case or a domestic exposure event.
Vector-Borne Transmission
Q Fever
Q fever registrations reached 7 confirmed cases in Week 17, rising from 2 cases in Week 16—a 250% week-over-week increase. The ZRZ district-level data identify Stara Zagora as the dominant focus, accounting for 6 of the 7 weekly cases; the remaining case was registered in Burgas. Q fever is caused by the obligate intracellular bacterium Coxiella burnetii, which is maintained in livestock reservoirs—particularly cattle, sheep, and goats—and transmitted to humans primarily through inhalation of contaminated aerosols generated during parturition, manure handling, or processing of animal products. The spring lambing and calving season in Bulgaria corresponds precisely to the characteristic seasonal peak of Q fever, and the concentration in Stara Zagora district—which encompasses significant agricultural and livestock farming activity—is epidemiologically consistent with occupational or peri-domestic exposure in rural settings. The year-to-date total of 20 cases in 2026 exceeds the 16 cases registered in the same period of 2025. Clinicians in affected districts should be alert to the diagnosis in febrile patients with livestock exposure and ensure confirmed cases are reported to support contact and source investigation.
Lyme Borreliosis
Three confirmed cases of Lyme borreliosis were registered in Week 17, an increase of 2 from the single case in Week 16 (+200%), though the absolute numbers remain small. The year-to-date total of 51 cases is 12% below the 58 cases in the same period of 2025, indicating that cumulative tick-borne disease activity has not exceeded the 2025 baseline at this point. One confirmed case of Lyme neuroborreliosis was additionally registered in Week 17—the first of 2026 nationally—an indication of neurological dissemination of Borrelia burgdorferi s.l. infection that requires prompt parenteral antibiotic therapy. The onset of April corresponds to the primary active period for Ixodes ricinus populations in Bulgaria, and Lyme borreliosis registrations are expected to increase through the spring and early summer months.
Contact and Sexual Transmission
Sexually Transmitted Infections
The STI surveillance signals established in preceding weeks of 2026 persist with notable variation in Week 17. Gonorrhea registered 5 confirmed cases, an increase of 2 from the prior week (+67% week-over-week), though the public health relevance of this figure derives principally from the sustained cumulative excess: 82 cases through Week 17 of 2026 versus 25 in the same period of 2025—a 228% year-over-year increase that represents the most dramatic relative rise among all STIs under surveillance in Bulgaria this year. Neisseria gonorrhoeae infections are of concern both for their direct sequelae and for the global emergence of strains with reduced susceptibility or resistance to extended-spectrum cephalosporins, the current last-line therapy; Bulgarian surveillance does not routinely report antimicrobial susceptibility data alongside case notifications, limiting capacity for resistance monitoring.
Urogenital chlamydial infection registered 3 confirmed cases in Week 17, a decrease of 4 from the 7 in Week 16 (−57% week-over-week). The cumulative year-to-date total of 111 cases nonetheless remains 147% above the 45 cases registered in the same period of 2025. Syphilis showed a sharp single-week decline from 21 cases in Week 16 to 2 cases in Week 17, a change of −90% that, if sustained, may reflect natural fluctuation in an outbreak-level signal or a reporting anomaly; the year-to-date total of 119 cases in 2026 is nearly identical to the 122 cases in the same period of 2025, suggesting overall stability at the level of cumulative burden despite week-to-week volatility.
Respiratory and Droplet Transmission — Bacterial
Bacterial Meningoencephalitis (Pneumococcal)
Four confirmed cases of pneumococcal bacterial meningoencephalitis were registered in Week 17, an increase of 4 from the zero cases in Week 16. While the absolute number remains small, the week-over-week appearance from nil is noted. The year-to-date total of 13 cases is identical to the 13 registered in the same period of 2025, indicating no deviation from the established baseline. Streptococcus pneumoniae meningitis carries a case fatality rate of 20–30% in adults and a significant burden of neurological sequelae in survivors; vigilance for this diagnosis in patients presenting with the classic triad of fever, neck stiffness, and altered consciousness is clinically essential, and pneumococcal conjugate vaccination remains the primary preventive measure.
Additional Signals from Regional Animal Disease Surveillance
Two animal disease notifications in Bulgaria’s immediate geographic vicinity carry indirect public health relevance for Week 17. Romania has reported an ongoing sheep pox and goat pox event—confirmed by PCR in Voivodeni locality on 23 April 2026—affecting 398 domestic sheep, with stamping out of all animals and movement controls applied. This is the first occurrence of this disease in the affected zone, and the event remains active. Although sheep pox and goat pox viruses (genus Capripoxvirus) are not transmissible to humans, the proximity of the outbreak to Bulgaria’s northern border warrants attention from veterinary authorities for border surveillance. Armenia reported a single rabies case in a domestic dog in Gandzakar on 27–28 April 2026, classified as a recurrence of an eradicated disease; while geographically distant, the case reinforces regional circulation of rabies virus in the Caucasus and underscores the importance of animal vaccination and post-exposure prophylaxis protocols for travellers.