The US CDC has updated the areas at risk for chikungunya. As of 13 Jan 2026, there is a chikungunya travel health notice for outbreaks in (red = new compared to last update 16 Dec 2025):

• Bangladesh
  
• Cuba
  
• Guangdong Province, China
  
• Sri Lanka
  

Countries considered to have an elevated risk for chikungunya include:

• Brazil
  
• Bolivia
  
• Colombia
  
• India
  
• Mexico
  
• Nigeria
  
• Pakistan
  
• Philippines
• Thailand

Nestlé issued consumer advisories and recalls for specific infant formula batches in multiple markets due to a potential quality issue involving an ingredient (ARA oil) and possible cereulide toxin contamination; advisories emphasize following country-specific batch lists and guidance.

Environmental monitoring in Santa Catarina reported a substantial proportion of monitored coastal points as unsuitable for bathing, with elevated E. coli at several beaches. Authorities reported increased gastroenteritis linked to exposure to contaminated seawater and non-potable water, and advised avoiding swimming shortly after heavy rain and checking official water-quality updates before bathing.

Guatemala confirmed a cluster of measles cases linked to a large religious mass gathering in Santiago Atitlán (Dec 2025), with cases detected in multiple departments and an epidemiological alert issued in early Jan 2026. Authorities implemented enhanced surveillance, active case finding, and vaccination response measures.

One confirmed mpox case was detected in Mayotte on 08 Jan 2026 in a traveler arriving from Madagascar, where an mpox outbreak is ongoing.

In response, neighboring countries have implemented control measures:

• Comoros requires travelers from Madagascar to present a medical certificate issued within five days prior to departure.
  
• Mauritius has classified Madagascar as a country at risk and has introduced enhanced passenger screening.

Since 16 December 2025, Madagascar has reported approximately 100 suspected mpox cases and around 10 confirmed cases, with the Mahajanga coastal region in northwestern Madagascar remaining the outbreak epicenter.

According to local media citing regional health director Dr. Seynabou Ndiaye, the Rift Valley fever (RVF) outbreak in Senegal’s Saint-Louis Region was declared over on 10 January 2026, with no patients remaining under surveillance.

The outbreak, declared on 21 September 2025, resulted in 360 confirmed cases from 5,196 tested samples, including 21 deaths (case fatality rate: ~5.8%). Nationwide, more than 500 confirmed human cases were reported by December 2025.

As of 8 January 2026, 18 villages in Pamekasan Regency, located on theMadura Island, East Java, Indonesia, were declared experiencing "Extraordinary Events" (KLB), with the highest suspected case counts in Proppo (193), Pamekasan (167), and Padmawaru (131).

In 2025, the regency reported 1’248 measles cases and 12 deaths, predominantly among children under five. Of 209 laboratory-confirmed cases, 78% were unvaccinated, while 22% had received only one dose. Also other regions in East Java reported outbreaks in 2025.

In 2025, Taiwan reported 477 confirmed acute hepatitis A cases, the highest annual total since 2017, including 447 local and 30 imported infections. Most cases were men (82.8%), primarily aged 30–39 (36.2%) and 20–29 (28.5%).

Case numbers rose sharply after March, with 50–65 new cases monthly from July to November, and nearly 40% of domestic cases were linked to intimate contact with infected individuals.

Australia experienced an unprecedented influenza activity during the 2025–2026 season, with more than 457’000 confirmed cases and high transmission continuing through December 2025 and January 2026, a period when influenza typically subsides. The outbreak is largely driven by the H3N2 subclade K.