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In his presentation at the 132nd Congress of the German Society for Internal Medicine (DGIM) 2026 in Wiesbaden, Germany, Tomas Jelinek, MD, medical director of the Berlin Centre for Travel and Tropical Medicine (BCRT) and the scientific director of the Centre for Travel and Tropical Medicine in Düsseldorf, Germany, gave a brief overview of the global epidemiologic situation and recommendations for travel-related vaccinations.

Underestimated Tick-Borne Encephalitis (TBE) Risk

“You don’t have to travel at all for tick-borne encephalitis (TBE),” Jelinek began. “The weather is nice, the season is starting, and we’re already seeing the first patients with tick bites.” TBE now occurs in large parts of Germany. The Robert Koch Institute in Berlin defines TBE risk areas as regions with more than one case per 100,000 residents and displays these zones on maps. Jelinek warned that unshaded areas are often mistakenly seen as “risk-free,” a misconception that can lead people to underestimate their personal risk. He said adult vaccination rates in Germany remain low and urged physicians to do more — especially by offering TBE prevention to patients who spend significant time outdoors.

Measles Resurgence Warning

Measles can affect both travelers and residents, and high case counts are possible across Europe. Since the COVID pandemic, measles have resurged because vaccination rates fell, whereas social contact was reduced — an understandable consequence that nonetheless caused vaccine coverage to decline. The World Health Organization warned about this trend in 2021. Before travel, clinicians should verify measles immunity and administer the vaccine when there’s any doubt.

Rare, Vaccine-Preventable Encephalitis

Japanese encephalitis is rare but can be severe, and an effective vaccine is available. The virus circulates in animal reservoirs — including pigs, water buffalo, and poultry — and is spread by night-active Culex mosquitoes. Human cases are uncommon, but when they occur, the infection can cause severe encephalitis, and survivors often have lasting neurologic damage. Since 2022, cases have also been reported in Australia, especially along the east coast and in the south. For travel vaccination, Jelinek said typical candidates include people on work and travel stays — for example, young travelers working on farms — who should be considered for immunization.

Yellow Fever Vaccine

The yellow fever vaccine is a standard travel vaccine — a live attenuated formulation with the expected adverse event profile and contraindicated in immunosuppressed patients. Product information advises that vaccination after age 60 should be given only after a strict benefit-risk assessment. “As a stand-alone age cutoff that’s basically obsolete,” Jelinek said. Data, including studies from Europe, indicate that complications after this live vaccine are linked to immunosuppression rather than age alone. “Frailty is the criterion, not age!” Since 2022, Germany’s Standing Committee on Vaccination (STIKO), the national immunization advisory body, has recommended repeating the yellow fever vaccine after 10 years, guidance that caused considerable concern in the field. Experts continue to maintain that a single yellow fever vaccination provides lifelong protection; systematic reviews show no evidence of waning long-term immunity. The only exception is when a destination country requires a second dose (eg, Venezuela).

Dengue: Vaccination Recommendations Debated

Dengue vaccination guidance remains controversial. Jelinek called dengue a “time-consuming” topic in travel medicine consultations because it requires extensive explanation. He added that dengue is “not terribly deadly, but it’s very common.” The disease is transmitted by day-biting Aedes mosquitoes that have adapted to urban environments — “We even have them in central Berlin now,” he noted — underscoring their local spread. With four serotypes in circulation, an effective vaccine ideally protects against all of them. Europe’s first licensed dengue vaccine later had its approval withdrawn after concerns about antibody-dependent enhancement (ADE). A newer live attenuated vaccine with an improved safety profile is now available, but protection is incomplete, particularly against serotype 3 in seronegative people. Jelinek said, “The vaccine is safe. At BCRT, we’ve now administered well over 100,000 doses. So far we have not seen a single case of ADE.” He argued that STIKO’s current recommendation — that the vaccine be given only to people with prior dengue infection and only if both doses can be completed 3 months before travel — is no longer tenable. “It’s simply wrong and endangers travelers,” he said. The German Society for Tropical Medicine, Travel Medicine and Global Health has issued a position statement on the issue.

Chikungunya — Growing Importance

For a long time, chikungunya was less prominent, but that has changed, in part due to a large outbreak in the Indian Ocean region last year. Chikungunya is an alphavirus transmitted by the same mosquitoes that spread dengue. One distinguishing feature of chikungunya outbreaks is that they come in large waves with many affected people and then fade, whereas “dengue is somehow always present in the countries — that’s the difference,” Jelinek said. Two vaccines provide very good protection: one live vaccine and one inactivated vaccine. Both are given once starting at age 12. The live vaccine, of course, is not used in immunosuppressed or frail people. That disadvantage does not apply to the inactivated vaccine, which can achieve high seroconversion as early as day 8. The live vaccine takes longer to induce protection but may last longer. “The inactivated vaccine will probably need a booster — but we are still waiting for the data,” Jelinek predicted.

Meningococcal Disease — Important for Younger Travelers

Meningococcal vaccination is especially important for travelers up to age 25. In practice, clinicians typically administer one of the available tetravalent conjugate vaccines and are increasingly adding the meningococcal B vaccine. Polysaccharide vaccines are no longer used at the BCRT, and monovalent conjugate vaccines have fallen out of favor after STIKO —following more than a decade of debate — updated its guidance. STIKO now recommends meningococcal B vaccination for young children and the tetravalent ACWY conjugate vaccine for adolescents. The meningococcal conjugate vaccine protects against four capsular groups of Neisseria meningitidis — A, C, W, and Y — including serogroup W, which has been linked to recent outbreaks and atypical, sometimes severe presentations. Jelinek added that serogroup W “doesn’t follow the rules,” spreading into older age groups beyond 25; in affected regions, such as parts of sub‑Saharan Africa, vaccination is advised for people of all ages.

Typhoid — Limited Vaccine Effectiveness

Two vaccine options remain available for typhoid, but their effectiveness is limited. Based on the data, the oral vaccine is somewhat more effective than the injectable, so it is preferentially recommended. A major drawback of the injectable polysaccharide vaccine is that repeated use can lead to a reduced immune response (hyporesponsiveness).

Cholera: Off-Label Use Provides Additional Benefit

Outbreaks are currently building in East Africa, but cholera is still a relatively rare topic in travel medicine. An off-label use of the inactivated cholera vaccine is increasingly employed because it also affords protection against enterotoxigenic Escherichia coli, producing some reduction in travel-related diarrhea, according to Jelinek.

Preexposure Rabies Recommended

Jelinek pointed to a striking recent example — rabid seals along the South African coast that were likely infected by dogs. “That’s new; we’ve never had an issue with marine mammals before,” he said. For travel medicine counseling, he recommends preexposure rabies vaccination for travelers to countries where rabies is endemic and vaccines or timely postexposure care may be hard to obtain — a situation that unfortunately applies in many parts of the world. The rabies vaccine is well tolerated, and clinicians have extensive experience with its use.

mpox Transmission Shift

mpox continues to spread. The new clade 1b shows more efficient transmission that is no longer primarily sexual but also occurs through close skin contact. There is currently a cluster of more than 500 cases in Madagascar, and there was recently a small series of cases in Germany. Vaccination is considered for travelers to countries where mpox occurs when close contact with locals is likely — for example, backpackers in sub-Saharan Africa who travel in shared taxis.

Influenza — the Most Common Vaccine-Preventable Travel Illness

Influenza is the most common vaccine-preventable illness seen in returning travelers, so indications for vaccination should be broad. Jelinek favors expanding recommendations to include young adults, adolescents, and children, saying the current focus on traditional risk groups is too narrow. At minimum, travelers should be protected. For healthy adults, cell culture-based influenza vaccines are used; people with chronic conditions and adults older than 50 years should receive adjuvanted or high-dose formulations. Young children typically receive the intranasal, live attenuated vaccine.

Malaria — Anopheles stephensi Also in Africa

Jelinek warned that A stephensi is “a malaria problem mosquito.” Unlike other vectors, it has adapted to urban settings. This breeding in urban centers brought malaria into India’s cities. It is now spreading in Africa as well. He predicted this spread will likely upend local malaria epidemiology.

This story was translated from Coliquio, part of the Medscape Professional Network.