Forty-Two Degrees in Nicosia, Long COVID's Clotting Signal, and Europe's Worst Dengue Season in Years
Cyprus heat emergency, a landmark long COVID vascular study, a paediatric migraine approval, and Southern Europe's worst dengue season in years.
By Dr. Asher Knippel
Five developments from the past four days span the length of the Mediterranean: a heat emergency testing health systems from Nicosia to Naples, a major finding in long COVID's vascular biology, two drug and vaccine advances, and a regional epidemiological alert on dengue.
Sunday, 16 August: Cyprus and the Eastern Mediterranean Under a Level-3 Heat Alert
The Cyprus Ministry of Health activated a Level-3 heat-health alert on Saturday evening after Nicosia recorded a high of 42.3°C — the highest August temperature in the station's 74-year record — and the Mesaoria plain logged its third consecutive night above 29°C. EU Copernicus Climate Change Service monitoring placed 14–16 August among the five hottest consecutive three-day periods ever observed across the Eastern Mediterranean basin.
The World Health Organization's European Regional Office estimates that the two-week period ending today has produced approximately 1,800 excess deaths attributable to heat across EU member states, with the highest absolute burdens in Greece, Italy, and Spain. Heat stroke — characterised by confusion or altered consciousness, cessation of sweating, and core body temperature above 40°C — requires immediate emergency presentation; do not wait to see whether it resolves on its own.
Cyprus health authorities advise avoiding outdoor activity between 11:00 and 18:00, maintaining adequate hydration (at least 2.5 litres daily for adults), checking on elderly neighbours or relatives twice per day, and accessing public cooling centres if indoor temperatures exceed 35°C. The city of Larnaca has opened five cooling centres at municipal buildings. Copernicus data confirm that extreme heat events of this intensity are now occurring in Cyprus two to three times per decade more frequently than the 1990–2010 baseline — a structural shift that public-health infrastructure must plan for, not simply respond to.
Saturday, 15 August: Long COVID's Clotting Signal Persists Three Years After Acute Infection
A study published in Nature Medicine, led by researchers at University College London in collaboration with ten other European universities, finds that people with long COVID show measurably elevated platelet hyperactivation — an abnormal state of heightened clotting readiness — three years after their initial SARS-CoV-2 infection, compared with fully recovered matched controls.
The study enrolled 1,240 participants across six countries. Those carrying a WHO-defined long COVID diagnosis had significantly higher levels of activated platelet surface markers (P-selectin, CD63), circulating microthrombi, and fibrin degradation products than controls, independent of vaccination status, initial disease severity, or antiviral treatment history. The findings support a vascular mechanism: persistent microthrombi in small blood vessels may reduce oxygen delivery to organs including the brain and skeletal muscle, which would be consistent with the cognitive slowing, post-exertional malaise, and exercise intolerance most commonly reported by people with long COVID.
This is an observational study. It identifies a biological signal with strong epidemiological consistency; it does not yet establish whether platelet hyperactivation drives symptoms or is an epiphenomenon. Two randomised trials of antiplatelet therapy in long COVID — one at King's College London and one in Berlin — are currently recruiting, with results expected in 2027. People experiencing long COVID symptoms should not self-administer antiplatelet or anticoagulant drugs without medical guidance.
Friday, 14 August: EMA Approves Rimegepant for Adolescents — First Oral CGRP Drug for Under-18s in Europe
The European Medicines Agency has extended the marketing authorisation for rimegepant (Vydura) to include acute treatment of migraine in adolescents aged 12 to 17, making it the first oral calcitonin gene-related peptide (CGRP) receptor antagonist approved for paediatric use anywhere in Europe.
The extension is based on a double-blind phase-3 trial of 342 adolescents published in The Lancet Neurology, in which a single 75 mg dose of rimegepant achieved pain freedom at two hours in 28% of participants versus 13% on placebo; the 24-hour sustained pain-freedom rate was 22% versus 9%. Adverse events were mild and consistent with adult trial data — nausea in approximately 3% of participants and no hepatotoxicity signal.
Migraine affects roughly 8% of adolescents and is among the leading causes of school absence in the 12–18 age group. Current paediatric-licensed acute options in Europe are largely limited to non-specific analgesics; most triptans, though used off-label in adolescents, are not formally approved for under-18s in most EU member states. Rimegepant's CGRP-blocking mechanism does not cause the vasoconstriction that restricts triptan use in patients with cardiovascular risk factors. The EMA authorisation is effective across all 27 member states immediately; UK NICE appraisal is expected by early 2027.
Friday, 14 August: Moderna's mRNA RSV Vaccine Holds 78% Efficacy Against Severe Disease at Two Years
Two-year follow-up data from the pivotal phase-3 trial of Moderna's mRNA RSV vaccine mRNA-1345 (Mresvia), published in The New England Journal of Medicine, show that the vaccine retains 78% efficacy against severe lower-respiratory-tract disease in adults aged 60 and older — with no statistically significant waning compared with the one-year readout.
The trial enrolled 36,000 participants across 22 countries. Severe RSV disease was defined as hospitalisation or respiratory failure attributable to RSV lower-respiratory infection. Efficacy against any symptomatic lower-respiratory illness fell from 79% at year one to 65% at year two — a modest decline that the authors describe as consistent with general patterns of mRNA vaccine immune kinetics rather than evidence of meaningful immune escape. No new safety signals emerged in the second year.
RSV causes an estimated 14,000 deaths per year in adults over 60 within the EU, primarily during winter months. The UK's Joint Committee on Vaccination and Immunisation is expected to advise this autumn on whether adults who received their first Mresvia dose in 2024 require a booster for winter 2026–27, with immunocompromised adults likely to be prioritised. The two-year data provide reassurance that the current single-dose recommendation for immunocompetent older adults remains well-supported.
Thursday, 13 August: ECDC Mid-Season Dengue Alert — 847 Local Cases in Southern EU, Nearly Double the Full 2025 Season
The European Centre for Disease Prevention and Control reports that locally acquired dengue cases in southern EU member states reached 847 as of 14 August — nearly double the 438 recorded across the entire 2025 transmission season — with 73% concentrated in Italy, 18% in Spain, and the remainder in France and Croatia. All four dengue serotypes are circulating; DENV-3 is dominant in Italy and DENV-1 in Spain.
The primary vector, Aedes albopictus (the tiger mosquito), has continued to extend its range northward into Central Italy and Catalonia, establishing in areas that recorded no activity a decade ago. The insect bites at dawn and dusk and breeds prolifically in small volumes of stagnant water — bottle caps, blocked drains, plant-pot trays — making urban gardens and terraces particularly productive larval habitats.
Cyprus has not recorded a locally acquired dengue case in 2026, though A. albopictus is present in coastal areas and sporadic imported cases have been confirmed. The Cyprus Ministry of Health advises eliminating standing water on properties, using repellents containing DEET or picaridin during dawn and dusk outdoor activity, and presenting to any medical facility within 24 hours if a sudden high fever, severe headache, and muscle or joint pain develop within 14 days of outdoor exposure. There is no EMA-licensed dengue vaccine available for adults without prior confirmed dengue infection; Dengvaxia is restricted to seropositive individuals aged 9–45.
This article is a journalistic summary of recent health and medicine developments compiled for general information purposes. It does not constitute medical advice. Readers should consult a qualified clinician before making any change to their treatment, medication, or health plan.