Epidemic and emerging disease alerts in the Pacific as of 03 March 2026

Highlights/updates since the last map was sent on PacNet on 24 February 2026:

Dengue

• New Caledonia: As of 26 February 2026, 117 dengue cases have been reported in New Caledonia since the 01 January 2026, including 104 confirmed and nine probable locally acquired cases, alongside three imported cases and one clinical case. DENV‑1 remains the predominant serotype among locally acquired cases, while DENV‑2 was identified in one imported case. The mean age of cases is around 30 years, with a slight female predominance (sex-ratio H/F: 0.8). Eight cases required hospitalisation, all of whom have recovered. Dengue transmission has reached a high level of circulation, with 43 cases reported in January and 74 in February, exceeding all monthly peaks observed since the implementation of the World Mosquito Program in 2020. Overall, 19 municipalities are affected (incidence rates 43 per 100,000 inhabitant), with increasing transmission observed outside Greater Nouméa, while the situation within Greater Nouméa remains relatively stable. The blue alert for DENV-1 remains in effect.– Source: La dengue | Direction des Affaires Sanitaires et Sociales de Nouvelle-Calédonie accessed on 03 March 2026 and Dengue Update shared with PPHSN Coordinating Body Focal point on 26 February 2026.
• Samoa: As of 22 February 2026, Samoa continues to experience a prolonged dengue outbreak, with 16,974 cumulative clinically diagnosed and laboratory‑confirmed cases reported since 01 January 2025. During EpiWeek 08 (16 – 22 February 2026), 157 new cases were reported, representing a 24% decrease compared with the previous week, alongside 12 new hospital admissions, including one ICU admission and one additional dengue‑related death, bringing the total number of deaths to 10. Transmission remains widespread, with 64% of cases reported from Upolu and 36% from Savaii, and children under 15 years accounting for 74% of cases. DENV‑1 remains the predominant circulating serotype (91%), with ongoing co‑circulation of DENV‑2 (9%). Health authorities continue outbreak response activities, including surveillance, risk communication and community engagement, while monitoring trends in severe disease and hospitalisation. The blue alert for DENV-1 and DENV-2 remains in effect. – Source: Dengue Fever Outbreak Situation Report in Samoa Issue No 45 shared with PPHSN Coordinating Body Focal point on 02 March 2026.

Measles

• Australia: Measles activity in Australia continues in early 2026, with 16 cases notified to the National Notifiable Diseases Surveillance System (NNDSS) during 02 – 15 February 2026 period. As of 15 February 2026, a total of 41 cases have been notified nationally, driven primarily by imported cases and subsequent local transmission, particularly in New South Wales, Victoria, and Queensland. On 28 February, NSW Health published a measles alert, noting that the source of infection for a recently confirmed case remains unknown, suggesting ongoing community transmission. In Queensland, measles activity remains linked to importation, with eleven cases reported in 2026 to date, including recent exposure events in the Cairns and Hinterland regions, prompting renewed public health alerts and contact tracing efforts. The red alert for measles in Australia remains in effect. – Sources: National Notifiable Diseases Surveillance System (NNDSS) fortnightly reports – 2 to 15 February 2026 | Australian Centre for Disease Control, Measles alert for South Western Sydney, Measles alert for Cairns | Queensland Health and National Communicable Diseases Surveillance Dashboard accessed on 03 March 2026.

Pertussis/Whooping cough

• New Zealand: Pertussis activity in New Zealand shows a continued gradual decline in weekly notifications, although transmission remains ongoing nationally. As of the week ending 20 February 2026, 37 cases were reported, down from 46 cases the previous week, bringing the total reported cases for 2026 to 375. The blue alert for pertussis remains in effect. – Sources: Pertussis dashboard accessed on 03 March 2026.

Rotavirus

• Kiribati: The rotavirus outbreak in Kiribati has expanded rapidly, with 1,397 diarrhoeal cases reported as of 1 March 2026, including 147 laboratory‑confirmed and 37 probable rotavirus cases. Transmission is widespread across South Tarawa, North Tarawa and Betio, with Betio reporting the highest number of cases, followed by Bonriki, Teaoraereke and Temaiku. Children under five years of age remain the most affected, although cases range from 2 months to 84 years, and 14 patients have required hospitalisation, primarily among paediatric cases. To date, no cases have been reported from the outer islands, and extended clinic operating hours (up to 10:00 pm) have been implemented at selected facilities to reduce pressure on the main hospital. Public health response activities are ongoing and include enhanced surveillance, laboratory confirmation, contact tracing, environmental health interventions, and community awareness activities led by the Health Promotion Unit. The red alert for Rotavirus remains in effect. – Sources: Rota Virus Outbreak Situational Report 4 shared with PPHSN Coordinating Body Focal point on 03 March 2026.

Other Information:

Ciguatera

• Vanuatu: As of 02 March 2026, Vanuatu’s Ministry of Health has confirmed an outbreak of ciguatera fish poisoning, with 44 cases reported between January and mid‑February 2026 across six islands (Efate, Tanna, Ambae, Pentecost, Maewo, and Santo). No deaths have been reported, and two hospitalised patients have fully recovered. The public is advised to avoid high‑risk reef fish, follow guidance from fisheries authorities, and seek medical care if symptoms occur, while health authorities continue routine monitoring through syndromic and notifiable disease surveillance systems, with efforts ongoing to address potential under‑reporting and ensure data quality. – Source: Vanuatu’s Ministry of Health - outbreak of ciguatera fish poisoning accessed on 03 March 2026.

Dengue

• Federated States of Micronesia: As of 17 February 2026, dengue activity continues at low but ongoing levels in Chuuk State, with 13 laboratory‑confirmed cases identified among 53 patients screened since December 2025, including one additional confirmed case detected on 16 February 2026. Confirmed cases have been reported from multiple locations with evidence of clustered transmission. The most recent confirmed case was hospitalised with mild illness and has since recovered. To date no severe cases or deaths have been reported. Surveillance, active case finding, vector control, and community awareness activities remain ongoing, while specimens from confirmed cases have been sent overseas for dengue virus genotyping, with results pending. – Source: Chuuk Dengue Situation Report 6 shared with PPHSN Coordinating Body Focal point on 27 February 2026
• New Zealand: In New Zealand (NZ), during EpiWeek 08 (21 – 27 February 2026), 14 confirmed imported dengue cases, three probable cases and two cases under investigation were reported. Among confirmed cases, 64% had returned from the Cook Islands, 29% from Samoa, 7% from Sri Lanka. The 3 probable cases had been to the Cook Islands. Given the known serological cross‑reactivity between dengue and other flaviviruses, some reported dengue cases may ultimately be reclassified as other flavivirus infections as epidemiological and laboratory investigations continue. – Source: NZ Arbovirus Notifications by Country (08: 21/02/2026–27/02/2026) shared with PPHSN Coordinating Body Focal point on 02 March 2026.
• Tokelau: Dengue activity has been reported in Tokelau, with the Department of Health issuing a public health advisory on 26 February 2026 following the detection of dengue fever cases in Atafu. Health authorities have disseminated information on dengue symptoms, transmission, and preventive measures, including mosquito control, personal protection, and early health‑seeking behaviour. Community awareness activities and surveillance remain ongoing to support early detection and limit further transmission, while authorities continue to monitor the situation closely. – Source: Tokelau Health Department Facebook page accessed on 03 March 2026.

Norovirus

• Federated States of Micronesia: A norovirus outbreak is ongoing in Pohnpei State, with 12 cumulative cases reported as of 27 February 2026, including three new cases since 19 February 2026. The first case was detected on 28 January 2026. The majority of cases (75%) are children under five years of age, with an age range of 6 months to 57 years, and 92% of cases have required hospitalisation. Cases are geographically dispersed across the state. Two deaths have been reported among hospitalised paediatric cases. Laboratory investigations confirm ongoing norovirus transmission, with co‑detection of other gastrointestinal pathogens, and public health authorities have implemented enhanced surveillance, infection prevention and control measures in healthcare settings, and community health education, while continuing to closely monitor the situation. – Source: Norovirus Outbreak Report No.2 shared with PPHSN Coordinating Body Focal point on 02 March 2026.

Pertussis/Whooping cough

• Federated States of Micronesia: As of 26 February 2026, pertussis activity continues in Pohnpei State, with 20 cumulative cases reported (10 laboratory‑confirmed and 10 suspected), including four new cases since 18 February 2026. Most cases are among adults, although four paediatric cases have been reported, and vaccination coverage remains low in both children and adults. Cases are geographically dispersed, with no recent travel history, indicating ongoing local transmission. No hospitalisations or deaths have been reported. Laboratory testing confirms continued circulation of Bordetella pertussis, including respiratory co‑infections. Public health authorities continue enhanced surveillance, contact tracing, risk communication, and vaccination promotion, particularly among frontline health workers and close contacts. – Source: Pertussis Situation Report, Issue no. 5 shared with PPHSN Coordinating Body Focal point on 02 March 2026.

Respiratory Syncytial Virus

• American Samoa: The American Samoa Department of Health is reporting an increase in Respiratory Syncytial Virus (RSV) cases in the community and is urging residents to take steps to reduce transmission. RSV is a common respiratory virus that can cause mild cold-like symptoms but may lead to severe illness in infants, older adults, and people with underlying health conditions. The public is advised to watch for symptoms, practice good hygiene, protect high‑risk groups, and seek care at a health centre or hospital if symptoms worsen. – Source: RSV Public Service Announcement - American Samoa Department of Health accessed on 03 March 2026.

Rotavirus

• Marshall Islands: As of 22 February 2026, the Ministry of Health and Human Services of the Republic of the Marshall Islands reported eight laboratory‑confirmed rotavirus cases in Majuro, detected through BioFire testing. The identification of these cases has prompted clinical alerts and heightened surveillance for acute watery diarrhoea, particularly among children and older adults. Health authorities have advised early case detection, appropriate clinical management, and containment measures, while noting that overall diarrhoeal syndrome activity during the reporting period remains below national alert thresholds. – Source: RMI communicable disease weekly report (report for week 16/02/2026 – 22/02/2026) shared with PPHSN Coordinating Body Focal point on 27 February 2026.