Vaccine News

The Regional Health Agency (ARS) of Réunion has recently confirmed a second imported case of smallpox (mpox) from the Republic of Madagascar to the French Department of Réunion.

As of February 10, 2026, the ARS reported that there is no established epidemiological link between this new case and the first case confirmed on January 22, 2026.

An investigation has been conducted to identify at-risk contacts in Réunion, who have been individually informed and directed to seek medical follow-up. This follow-up may include the prescription of a reactive vaccination as soon as possible.

The ARS reminds everyone that anyone with suggestive symptoms (skin rash, ulcers, fever, swollen lymph nodes, etc.), particularly travelers returning from Madagascar or an area with active virus circulation, should contact their doctor or the SAMU-Centre 15 immediately, and isolate themselves immediately while awaiting medical advice.

Furthermore, in accordance with national recommendations, preventive vaccination (JYNNEOS®, MVA-BN®) is offered to the most exposed people (travelers going to areas of active circulation, people with multiple sexual partners, sex workers, exposed health professionals, and immunocompromised people.

And reactive vaccination is offered to at-risk contacts of confirmed cases, ideally within 4 to 14 days after exposure.

Vaccinations are carried out at authorized vaccination centers, such as the North and South University Hospital and CEGIDD West.

Mpox clade Ib cases in Madagascar began in late 2025, marking the country's first documented outbreak. As of early February 2026, approximately 250 confirmed mpox cases had been reported, concentrated in the Boeny region.

This report concerns tens of thousands of travelers who visit this island off Africa's eastern coast each year.

Before visiting Madagascar in 2026, the U.S. CDC recommends that at-risk travelers receive their first mpox vaccine at least 6 weeks before travel, if possible. Numerious travel vaccine clinics in the U.S. offer mpox vaccination services.

The Pan American Health Organization (PAHO) issued an epidemiological alert on February 10, 2026, warning of a sustained rise in chikungunya cases across parts of the Americas.

The alert highlights increased transmission from late 2025 through early 2026, including the resumption of local transmission in territories that had not reported the virus for several years, including the United States.

While rarely fatal, the illness can cause debilitating long-term effects.

According to PAHO's alert, as of epidemiological week (EW) 4 in 2026, a total of 7,150 chikungunya cases had been reported, with 2,351 confirmed and 1 death recorded.

This uptick follows a broader regional trend: in 2025, the Americas reported 313,132 cases (113,926 confirmed, including 170 deaths) across 18 countries and one territory.

Notable activity occurred in Brazil's central-western and southeastern regions, southern Bolivia, and the re-emergence in the Guiana Shield area (including Guyana, French Guiana, and Suriname after nearly a decade without reports.

The PAHO noted that while dynamics may reflect cyclical epidemiology, the reappearance in previously quiet territories underscores the urgency for heightened vigilance.

Genomic analysis shows three main global genotypes of the chikungunya virus: West African, East/Central/South African, and Asian. Specifically, the Indian Ocean lineage, which features the E1-A226V mutation, enhances transmissibility, contributing to wider spread in some contexts.

Chikungunya is a viral disease transmitted primarily by Aedes aegypti and Aedes albopictus mosquitoes, the same vectors responsible for Dengue and Zika infections, which have also been reported in 2026.

In a positive development for prevention, approved chikungunya vaccines are expected to be available in 2026. These include virus-like particle options, such as the VIMKUNYA vaccine.

This vaccine is recommended for people visiting areas with chikungunya outbreaks and is commercially offered at certified travel clinics throughout the U.S.

Health officials in Florida are monitoring a significant increase in chikungunya fever cases, predominantly linked to travel from Cuba, where the mosquito-transmitted virus was associated with more than 50,000 cases in 2025.

According to week #5 data from the Florida Department of Health (DOH), the state recorded a high number of travel-associated cases this year.

As of early February 2026, health officials have reported 16 cases with onset in 2026 among individuals with a recent travel history from Cuba. The most affected counties include Miami-Dade (10 cases) and Palm Beach (2 cases).

In 2025, Florida reported 370 travel-associated chikungunya cases. Of these, 357 were linked to travel to Cuba.

Furthermore, the DOH reported a rare but notable case of locally acquired chikungunya fever in Miami-Dade County, with symptom onset in December 2025.

This marks the first instance of local transmission in Florida since 2014, when 12 cases were reported.

Local transmission in Florida indicates the virus was passed from an infected traveler to a resident through mosquitoes within the state, raising concerns about the potential establishment of the virus in areas with competent mosquito vectors in 2026.

As of February 12, 2026, the U.S.CDC maintains a Level 2 Travel Health Notice ("Practice Enhanced Precautions") for chikungunya in Cuba, advising travelers to use insect repellent, wear long sleeves and pants, and take other measures to prevent mosquito bites.

Additionally, the CDC advises travelers visiting chikungunya-endemic areas to speak with a vaccine expert about the 2026 immunization option.

The Mexican Ministry of Health has confirmed six new human cases of myiasis caused by the New World screwworm (NWS, Cochliomyia hominivorax), bringing the total number of reported human cases to 141 across eight states.

According to Epidemiologic Surveillance Report #4, the majority of cases—103—have been reported in Chiapas, where environmental conditions have facilitated ongoing transmission.

While human cases are relatively uncommon compared to infections in animals, as of February 9, 2026, over 600 cases have been reported in livestock and other animals nationwide, highlighting the broader impact of this serious health risk.

The NWS is a parasitic fly native to parts of the Americas. It lays its eggs in open wounds or on the mucous membranes of warm-blooded animals, including humans. The eggs hatch into larvae that burrow into living tissue, feeding on flesh and causing severe damage, pain, and potential secondary infections.

If left untreated, infestations can lead to serious complications and, in rare cases, may be fatal.

International health authorities are actively monitoring the situation through enhanced surveillance efforts.

Currently, the U.S. government is involved in regional initiatives that include sterile insect technique programs aimed at reducing fly populations and preventing further northward spread.

Animal cases (primarily in livestock) have been detected close to the Texas border, raising concerns about potential northward spread:

Tamaulipas has reported 8 active animal cases, and Nuevo León has had confirmed animal cases, including one in Sabinas Hidalgo, less than 70 miles from the Texas border.

Officials emphasize that the risk to the general public remains low with proper hygiene and wound care; however, vigilance is essential in endemic and outbreak areas.

As of February 12, 2026, no vaccines are available to protect people from this health risk.

The yellow fever outbreak in the Republic of Colombia has intensified, with the latest data showing a continued rise in cases and fatalities in 2026.

As of February 8, 2026, Colombia's Ministry of Health confirmed 168 yellow fever cases, including 76 deaths, according to a Facebook post.

This new data represents an increase from earlier reports in late January 2026, when the cumulative total stood at 161 cases and 73 deaths.

Located on the northwestern coast of South America, the department of Tolima remains the epicenter, historically low-risk but now accounting for the majority of infections (previously reported at over 130 cases and dozens of deaths in the region alone).

Other Colombian departments include Caldas, Caquetá, Cauca, Guaviare, Huila, Meta, Nariño, Putumayo, and Vaupés.

The outbreak, which originated in late 2024 and escalated significantly through 2025, has been marked by a persistently high case-fatality rate, often exceeding 40-70% in various reporting periods, largely due to low vaccination coverage among affected populations in forested or rural areas where the mosquito-transmitted virus circulates.

With millions of travelers departing for Colombia from the U.S. each year, the Centers for Disease Control and Prevention's Travel Health Notice, Level 2, continues to recommend yellow fever vaccination for travelers to risk areas in Colombia at elevations generally below 2,300 meters, excluding major cities like Bogotá, Barranquilla, Cali, Cartagena, and Medellín.

Numerious health authorities urge residents and visitors in or traveling to endemic zones to get vaccinated at least 10 days before exposure, use mosquito protection, and seek immediate medical care if symptoms such as fever, headache, muscle pain, nausea, or jaundice appear. 

When departing from the United States for Colombia, travel vaccination clinics offer the YF-Vax vaccine.

The Hong Kong Special Administrative Region Government, through its Travel Health Service under the Centre for Health Protection (CHP), has cautioned residents to exercise care regarding Dengue fever when traveling abroad this year.

The advisory emphasizes that the disease is endemic in over 100 countries, particularly in Southeast Asia and the Western Pacific—popular destinations for Hong Kong travelers.

In an update posted on February 5, 2026, the Travel Health Service reiterated that Dengue remains a persistent threat in many tropical and subtropical regions.

As of early 2026, there have been six reported imported cases of Dengue.

In 2025, Hong Kong recorded 59 imported Dengue cases.

The countries that contributed the most cases last year include the Philippines (12 cases), Indonesia (11 cases), India (9 cases), and Thailand (9 cases).

Notably, there were no local transmissions reported last year.

Regionally, Dengue remains a challenge. As per cumulative figures from 2025, with partial data from 2026, Indonesia reported 148,922 cases, with 403 recorded in early 2026; Vietnam had 184,903 cases in 2025; and India reported 120,729 cases during the last year.

Travelers returning from areas where Dengue is prevalent should seek medical attention promptly if they feel unwell and inform their doctors about their travel history. Additionally, CHP says those planning to travel to these regions should take the necessary precautions against this mosquito-borne disease.

Seperately, the U.S. CDC recently stated, 'it has identified a higher-than-expected number of Dengue cases among returning U.S. travelers from certain countries in recent months.'

As of early 2026, there is currently no locally registered Dengue vaccine available for general use in Hong Kong, according to the Centre for Health Protection and the Department of Health.

However, in nearby dengue-endemic countries that are popular with Hong Kong travelers, the second-generation vaccine QDENGA® is available in various settings, including private clinics, national programs, and public health initiatives.

In the United States, QDENGA is unavailable in 2026, but the first generation is available in Puerto Rico, where Dengue has become endemic.

Detailed information on the latest Dengue fever situation in Hong Kong, as well as neighbouring and overseas countries and areas, is available on the Centre for Health Protection's website.

Over the past two decades, coronaviruses (CoV) have caused three significant disease outbreaks: severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019.

Diseases such as MERS continue to cause severe outcomes. There have been a total of 19 MERS-CoV cases reported worldwide since the beginning of 2025, including four fatalities.

To address these diseases with a single vaccine, a candidate designed to provide broad protection against coronaviruses has entered clinical testing.

The vaccine, named GBP511, is built on a self-assembling nanoparticle technology developed by researchers at UW Medicine and the Institute for Protein Design. The South Korean pharmaceutical company SK bioscience is conducting human clinical trials for this vaccine.

GBP511 builds on technology validated through SKYCovione, a vaccine that became the world's first computer-designed medicine to achieve regulatory approval.

In preclinical studies, GBP511 has shown the ability to protect animals from related viruses not directly targeted by the vaccine.

"The beauty of this approach is that by presenting the immune system with multiple related antigens at once, we can train it to recognize features that are conserved across the entire sarbecovirus family," explained David Veesler, a professor of biochemistry at UW Medicine and a Howard Hughes Medical Institute Investigator, who led the preclinical studies, in a press release on February 3, 2026.

He added, "That's exactly what you need to prepare for unpredictable future threats."

The international Phase 1/2 trial began enrolling participants in January 2026 and will assess safety and immune responses in approximately 368 healthy adults in Perth, Western Australia. The study's results are expected by 2028.

The Coalition for Epidemic Preparedness Innovations has supported the GBP511 program with approximately $65 million in funding.