The Ebola disease outbreak in D.R. Congo (676 confirmed cases) continues expanding geographically, concentrated in Ituri Province. Uganda's 19 linked cases remain confined to Kampala with no new cases for six days. Chikungunya is declining in Argentina (12,408 suspected cases; peak late April), transmission remains concentrated in the Northwest. French Guiana is intensifying, with 621 confirmed cases and the Littoral ouest sector in full epidemic phase since April. A presumptive Nipah virus case in Kerala, India involves a ventilated patient with encephalitis and 77 identified contacts (15 high/highest risk, all quarantined). No secondary cases to date; exposure source unconfirmed. Dengue is surging across Southeast Asia: Vietnam reports 50,000+ cases (2.5× 2025, DENV-2 dominant); Malaysia 33,367 cases (+20.7%, DENV-3 emerging in Sabah); Sri Lanka 36,168 cases and 20 deaths, coinciding with monsoon onset.
Ebola virus disease, Democratic Republic of the Congo and Uganda
As of 10 June, 676 confirmed cases including 136 deaths (CFR 20.1%) have been reported from the DRC, while Uganda has reported 19 confirmed cases with two deaths and one fatal probable case. The outbreak remains concentrated in Ituri Province (93% of cases), with Bunia, Rwampara, Mongbwalu, and Nyankunde as the most affected health zones. Geographic expansion continues. In Uganda, all 19 confirmed cases are linked to importation from DRC (14 imported, 5 secondary) and are confined to the Kampala Metropolitan Area. No new cases have been reported in Uganda for six days, and no community transmission has been documented. WHO risk assessment: very high for DRC, high for Uganda and neighboring land-border countries, low globally. No travel or trade restrictions are advised.
Chikungunya, Argentina, French Guiana
Argentina's 2025–2026 chikungunya season is declining following a late-April peak, with 95 cases recorded in the final week of May. The cumulative total reaches 12,408 suspected cases (2,642 confirmed or probable), heavily concentrated in the Northwest (96%), particularly Salta, Tucumán, and Jujuy. Local transmission is confirmed in Salta alongside importations from Bolivia, with secondary spread documented to Buenos Aires, Catamarca, Santiago del Estero, CABA, and Córdoba.
In French Guiana, transmission is intensifying: 621 confirmed autochthonous cases have been reported since January 2026, with the Littoral ouest sector (bordering Suriname) in full epidemic phase since 23 April, accounting for 70% of cases. The ongoing rainy season sustains Aedes activity through July. ECDC assesses traveller infection risk as currently low.
Nipah virus, India (Kerala)
On 10 June 2026, health authorities in Kozhikode district, Kerala, India reported a presumptive Nipah virus (NiV) case in a man in his forties presenting with encephalitis. The patient, currently hospitalised on ventilator support in stable condition, had visited multiple healthcare facilities since 10 May, complicating contact tracing. A total of 77 contacts were identified (58 healthcare workers, 14 family members, 5 others); 2 are classified as highest risk and 13 as high risk, with both groups under quarantine. No secondary cases have developed. The suspected exposure source is cleaning a warehouse, though this remains unconfirmed.
Dengue, Vietnam, Malaysia & Sri Lanka
Vietnam has reported over 50,000 dengue cases in the first five months of 2026: approximately 2.5 times the equivalent 2025 figure with four deaths in Ho Chi Minh City. Transmission is starting earlier, lasting longer, and spreading geographically beyond historically endemic southern provinces into the north. The dominant serotype is DENV-2. Malaysia recorded 33,367 cases nationally as of epidemiological week 23 (13 June), a 20.7% year-on-year increase. Sabah is the most affected state, with a 50.4% rise to 2,866 cases, concentrated in Kota Kinabalu, Tawau, and Sandakan districts, with a serotype shift to DENV-3. Sri Lanka has reported 36,168 cases and 20 deaths as of 5 June, roughly 10,000 more than the same period in 2025. The Western Province accounts for ~50% of cases (Colombo, Gampaha, Kalutara).
The ESCMID-AUMC Epi Alert, a strategic collaboration between the ESCMID Emerging Infections Subcommittee and the Center of Tropical Medicine and Travel Medicine of Amsterdam University Medical Center (AUMC) that integrates expertise and resources to advance emerging infectious diseases surveillance and intelligence sharing. This collaboration integrates ESCMID's extensive international network and emerging infections expertise with AUMC's proven surveillance capabilities, led by Dr. Abraham Goorhuis and the AUMC team and other collaborators form European Institutions.
The Epi Alert aims to be a weekly publication. The briefings are curated by infectious disease specialists prioritising data from trusted sources (such as Beacon, H-Radar, Outbreaknews, WHO, ECDC, CDC) based on potential impact, geographic region and urgency/relevancy to clinical practice. It aims to provide concise summaries for busy healthcare professionals with direct links for further investigation and transparency.
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Disclaimer: The information in this epi-alert is a weekly summary of the information that is available on the internet, mainly the websites of Beacon, H-Radar, Outbreaknews, WHO, ECDC, CDC, and others. For this summary, we consider issues that are most relevant to the ESCMID members involved in clinical patient care. Therefore, this report is not comprehensive, but we strive to include all major global issues in this report on a weekly basis.