| Indicator | 2025 Totals | 2026 (Jan–July) |
|---|---|---|
| Confirmed Cases | thousands | thousands |
| Reported Deaths | 21 | 3 |
| Hospitalizations | N/A | 172 |
WHO Western Pacific Regional Office surveillance of endemic dengue
Health authorities have issued alerts across the Pacific as of July 2026, due to ongoing dengue outbreaks. While dengue transmission is declining in New Caledonia, outbreaks persist in Vanuatu and other island nations. The World Health Organization (WHO) Western Pacific Regional Office continues to conduct indicator-based and event-based surveillance for dengue in the region, particularly in Member States where the disease is endemic. This surveillance aims to monitor the overall situation, detect unusual signals in case trends and severity, and assess risks in a timely manner to provide support for response.
Dengue Outbreaks in New Caledonia and Vanuatu
Direction des Affaires Sanitaires et Sociales de Nouvelle-Calédonie tracking DENV-1
In New Caledonia, the dengue epidemic appears to be easing as the region enters its cooler season, which is usually associated with a slowdown or interruption of transmission. According to data from the ALERTE DASS and the Direction des Affaires Sanitaires et Sociales de Nouvelle-Calédonie, a cumulative total of 2,181 dengue cases have been recorded since January 1, 2026, with 1,982 confirmed autochthonous cases. Serotype 1 (DENV-1) remains the only serotype circulating. The median age of cases is 29 years, and the male-to-female sex ratio is 0.9, with the highest incidence rates observed among 10–14-year-olds (338 cases) and 15–19-year-olds, mainly in school settings.
A total of 78 patients have been hospitalised in New Caledonia, including one in the 15 days prior to the July 5, 2026 report. Three deaths have been recorded: one in a person co-infected with leptospirosis and dengue, and two in persons with comorbidities. The territory-wide incidence rate stands at 804 cases per 100,000 inhabitants. Notably, 32% of declared cases reside in Grand Nouméa communes where the World Mosquito Program is deployed and where Wolbachia is present in approximately 80% of mosquitoes. Weekly incidence in this area has remained below 40 cases per 100,000 inhabitants, compared with a peak of around 200 per 100,000 outside Grand Nouméa at the end of April.
Meanwhile, as of July 2, 2026, a dengue outbreak remains ongoing in Shefa province, Vanuatu. Confirmation of the serotype in Vanuatu is pending.
Regional Surveillance and Multi-Country Trends
Pacific Syndromic Surveillance System reports for 2026
The Pacific region continues to monitor mosquito-borne illnesses through the Pacific Syndromic Surveillance System (PSSS). The PSSS has reported a total of many Dengue-like Illness (DLI) cases to date in 2026, a lower trend compared to the same period last year. In 2025, 12 dengue outbreaks were reported in Pacific Islands Countries and areas (PICs), including American Samoa, Cook Islands, Fiji, French Polynesia, Kiribati, Nauru, Samoa, Tonga, and Tuvalu. Throughout 2025, there were thousands of confirmed cases and 21 deaths reported across the Pacific, with fatalities in Fiji (n=8), Samoa (n=7), Tonga (n=3), Nauru (n=2), and Kiribati (n=1).
Between January 1 and July 2, 2026, a total of thousands of dengue confirmed cases, 172 hospitalisations, and three deaths have been reported across the Pacific. The most affected countries and areas in 2026 include the Cook Islands, French Polynesia, Samoa, and New Caledonia, which account for 94% of confirmed cases. Dengue serotype-1 (DENV-1) and serotype-2 (DENV-2) are currently in circulation in the region. Low levels of transmission are observed in American Samoa, Kiribati, New Caledonia, Samoa, and Tonga, while Wallis and Futuna is under monitoring due to recently reported community transmission.
Public Health Guidance and Response
Epidemiologists applying R0 to assess outbreak potential
Public health agencies define an epidemic as a sudden increase in the number of disease cases above what is normally expected in a specific population. Epidemiologists use a metric called the basic reproduction number (R0) to assess whether an outbreak has epidemic potential. R0 represents the average number of new infections caused by a single infected person; when R0 is greater than 1, the outbreak grows. This number helps public health teams predict how fast a disease could spread and how aggressive the response needs to be.
For regions under active dengue alerts, such as New Caledonia, the blue alert for dengue remains in effect. Health authorities advise the public to seek prompt medical care in case of fever, headache, or muscle and joint pain. In cases of suspected dengue, individuals are advised to avoid aspirin and ibuprofen. Readers should consult qualified medical professionals regarding specific health concerns or symptoms, as this information is for reporting purposes and does not constitute medical advice.
Find more reporting in our Health section.
Worth a look
Discover more from Archyworldys
Subscribe to get the latest posts sent to your email.
