Vaccine News

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. 

An unexpected measles outbreak at Ave Maria University in Collier County, Florida, has intensified, with at least 20 students now confirmed to have contracted the highly contagious viral infection.

As of February 6, 2026, three of these Florida students have been hospitalized due to complications from the illness.

Located northeast of Naples, the school officials stated on their website that they continue to provide care for all students, regardless of test results, and are closely monitoring the situation. In addition to the Padre Pio Campus Health Clinic, a second on-campus clinic has been established to support routine student care.

This outbreak represents the first significant measles activity in Collier County in nearly a decade, as there have been no reported cases during that time.

Alarmingly, university officials have noted that approximately 98% of the student population is vaccinated against measles, which exceeds the U.S. CDC recommendations.

The CDC reports data from 2025-2026, indicating that about 3% to 4% of total reported breakthrough measles cases in the U.S. occurred among people who had received 2 doses.

According to the Florida Department of Health (DOH), there were around 10 confirmed measles cases in southeast Florida (Broward County) in early 2024.

As of early February, the Florida DOH in Collier County is providing additional resources to monitor for suspected measles cases and to minimize further transmission.

Unfortunately, in a potentially related matter, further north in Florida, the administration of St. Petersburg Catholic High School confirmed on Friday, February 4, 2026, that a student has a confirmed case of measles.

The DOH says measles vaccination services are offered at public and commercial locations throughout Florida.

As the February 2026 vaccination plans are being formed, the UK Health Security Agency (UKHSA) has issued an important reminder for travelers heading to Cape Verde to take extra precautions against gastrointestinal infections when visiting the West African archipelago.

As of February 5, 2026, recent UKHSA data indicate a significant cluster of Shigella sonnei cases, a bacterial cause of severe dysentery-like illness, along with multiple clusters of non-typhoidal Salmonella infections strongly linked to recent travel to Cape Verde.

Since October 1, 2025, the UKHSA has confirmed 158 cases of Shigella sonnei in travelers returning to England, Scotland, and Wales. Of the 118 cases where international travel was reported, 112 (94.9%).

Many travelers to Cape Verde have visited the Santa Maria area on Sal Island and the Boa Vista area, popular resorts known for their beaches.

The UKHSA says this strain of Shigella sonnei shows no genomic resistance to the common antimicrobials typically used to treat traveler's diarrhea, which could facilitate treatment if an infection occurs.

Additionally, 32 cases were linked to travel to Cape Verde during the same period.

Investigations into the outbreaks are ongoing and involve international health partners. Cases have also been reported in other European countries, particularly from September to November 2025.

Shigella and Salmonella are primarily transmitted through contaminated food and water, poor hygiene practices, and person-to-person contact. The risk of infection is especially heightened in resort settings.

Symptoms typically appear within a few days, and while most people recover within a week with supportive care (with hydration being crucial), severe cases can lead to dehydration, hospitalization, or complications. This is particularly concerning for vulnerable groups such as young children, the elderly, and individuals with weakened immune systems.

The UKHSA emphasizes that while Cape Verde is a popular travel destination, increased vigilance can help prevent illness and ensure a safe holiday. Travelers who experience symptoms upon returning should seek medical advice and inform their doctor about their travel history.

From a prevention standpoint, no Shigella vaccine has received regulatory approval from any health authority as of February 2026.

However, the Shigella4V (S4V or S4V2) vaccine candidate received U.S. FDA Fast Track designation in 2024. Phase 2 studies (including in infants) are underway, but no Phase 3 completion or approval has been achieved yet.

Measles is an ongoing risk around the world, and children are at serious risk for the highly transmissible disease in most countries. Since 2023, measles incidence has been rising in many countries worldwide, including in Europe.

The Israeli Ministry of Health recently reported the 14th pediatric fatality due to measles since an outbreak began in mid-April 2025, partially from imported cases and others of unknown origin.

The Ministry's announcement on February 2, 2026, confirmed that the affected individual was a one-year-old who had not been vaccinated. The baby was brought to Hadassah Mount Scopus Hospital in Jerusalem in critical condition. 

Similar to previous cases, most of the deceased were healthy infants without any underlying conditions and had also not received vaccinations.

The Ministry emphasizes that measles is a preventable disease and advises that all children should receive their first vaccine dose at the age of one. In areas affected by the outbreak in Israel, the Health Ministry recommends administering the second dose of the measles vaccine at 18 months.

Additionally, an extra vaccine dose is recommended for infants aged 6 to 11 months in outbreak areas and for those traveling to outbreak areas.

As of February 5, 2026, the areas in Israel that have been classified as experiencing a measles outbreak are Jerusalem, Beit Shemesh, Bnei Brak, Harish, Modi'in Illit, Nof HaGalil, Kiryat Gat, Ashdod, Safed, Netivot, Haifa, Tiberias, the Mateh Binyamin Regional Council, and the settlement of Tekoa.

To alert international travelers to their health risk, the U.S. CDC has maintained a Level 1, Travel Health Notice, that identifies measles outbreaks in numerious countries. The CDC advises all travelers to speak with a local travel vaccine expert about measles immunization options and other vaccine-preventable diseases.

In the past year, the World Health Organization (WHO) reported over 600,000 cases of cholera or acute watery diarrhea and nearly 7,600 deaths across 33 countries.

However, these figures are likely underreported, as cholera cases often go unrecorded.

Today, Gavi, the Vaccine Alliance, UNICEF, and the WHO announced that the global supply of oral cholera vaccine (OCV) has increased sufficiently to resume life-saving preventive vaccination campaigns for the first time in over three years.

A first allocation of 20 million doses is being deployed for preventive campaigns.

Of these, 3.6 million doses were delivered to Mozambique; 6.1 million to the Democratic Republic of the Congo, which is also experiencing significant outbreaks; and 10.3 million doses are planned for delivery to Bangladesh.

"Global vaccine shortages forced us into a cycle of reacting to cholera outbreaks instead of preventing them. We are now in a stronger position to break that cycle. I thank EUBiologics, currently the only manufacturer producing cholera vaccines at the scale needed for mass vaccination campaigns, for its efforts, and urge others to enter this vital space. These vaccines will save lives," said Dr Tedros Adhanom Ghebreyesus, WHO Director-General, in a press release on February 4, 2026.

Over the last few years, the annual global supply of OCV has doubled from 35 million doses in 2022 to nearly 70 million doses in 2025. The doses are being financed by Gavi and procured and delivered to countries by UNICEF.

"The multi-year surge in cholera cases and resulting unprecedented demand for vaccines were stark reminders that sustainable, accessible vaccine supply is a global public good – and the world cannot afford complacency," added Dr Sania Nishtar, CEO of Gavi, the Vaccine Alliance.

"For the first time in years, this increase in vaccines will allow us to prevent large-scale cholera emergencies better," said Catherine Russell, UNICEF Executive Director. "Resuming preventive cholera vaccination will protect children and help stop this highly contagious disease in its tracks. But it must go hand in hand with other efforts, including better access to safe water and basic sanitation."

While global vaccine supply steadily improves, the one-dose strategy will remain the standard for outbreak responses, with the use of two doses considered on a case-by-case basis.

Cholera spreads through contaminated food and water, causing severe diarrhoea and dehydration. It can lead to death if it is not treated quickly. It is found in places without safe water and sanitation, mainly in localities affected by conflict and poverty.

The WHO says vaccination is only one aspect of cholera prevention and response. Long-term investments in safe water, sanitation, and hygiene infrastructure, alongside disease surveillance, rapid treatment, and community engagement, remain essential to prevent outbreaks from starting and spreading, and to reduce deaths in the long term.

In the United States, OCVs are offered at travel vaccine clinics, located in every state.