Vaccine News

In Italy, where the West Nile virus (WNV) has become endemic, a total of 718 confirmed cases, including 49 related fatalities, have been reported in 2025.

As of October 3, 2025, the most affected regions are Lazio (252 cases), Campania (124 cases), and Veneto (91 cases).

As of September 2025, Italy accounted for 76.3% of all reported human cases and for 79.6% of all reported outbreaks in equids and birds, underscoring the significant WNV activity in the country. 

Italy is not alone in reporting mosquito-transmitted WNV cases this year in Europe, as Albania, Bulgaria, France, Greece, Hungary, Romania, Serbia, Spain, and Türkiye have confirmed cases to the European Centre for Disease Prevention and Control.

Following several years of research, WNV vaccines remain unavailable in 2025.

The U.S. Centers for Disease Control and Prevention's (CDC) Vessel Sanitation Program (VSP) reports on various norovirus outbreaks onboard cruise ships.

According to the CDC's recent report, the Serenade of the Seas's current voyage (September 19, 2025–October 2, 2025), about 5% of passengers (94 of 1,874) experienced diarrhea and vomiting related to norovirus infections while traveling from San Diego to Miami.

The CDC reported on September 30, 2025, that, in response to the outbreak, Royal Caribbean International and the ship's crew implemented several measures, including enhanced cleaning and disinfection procedures, as outlined in their outbreak prevention and response plan.

The CDC wrote that norovirus is often a cause of GI illness outbreaks on cruise ships, but we don't always know the cause of the outbreak when we begin an investigation. Identifying the agent that caused an outbreak can take time.

So far in 2025, the VSP has identified approximately 19 cruise ship outbreaks, 15 of which were caused by norovirus.

The VSP reported 15 norovirus outbreaks aboard cruise ships in 2024.

While there are no approved norovirus vaccines available in 2025, a recent study showed that an oral vaccine candidate triggers antibodies that can neutralise a wide range of norovirus strains. It may also reduce the amount of virus that infected people shed, raising hopes that a broadly protective vaccine may be within reach. 

The U.S. Food and Drug Administration recently conditionally approved Dectomax-CA1 (doramectin injection) injectable solution for the prevention and treatment of New World screwworm larval infestations, as well as the prevention of NWS reinfestation for 21 days.

Dectomax-CA1, sponsored by Zoetis, is based in Michigan and is conditionally approved for use in cattle only, not for human use.

"We understand the urgency with which America's farmers and ranchers are asking for tools to fight New World screwworm," said FDA Commissioner Marty Makary, M.D., M.P.H., in a press release on September 30, 2025.

"Today's conditional approval – the first in the U.S. for NWS – shows our dedication to rapidly advancing important animal medicines when they are needed most. We continue to work tirelessly to complete the review of other NWS products to protect multiple animal species in the U.S." 

Dectomax-CA1 is eligible for conditional approval because it is intended to prevent and treat a serious or life-threatening disease in cattle, it addresses an unmet animal health need, and demonstrating the effectiveness of the drug would require complex or complicated studies.

Dectomax is already fully approved under a New Animal Drug Application for treatment and control of specific nematode and arthropod parasites in cattle and swine. NWS fly larvae burrow into the flesh of cattle, causing severe wounds and death if untreated.

Dectomax and Dectomax-CA1 contain the same active ingredient (doramectin injection) at the same dose. Because the original approval of Dectomax included adequate target animal safety studies, manufacturing information, and human food safety information, the FDA did not require new information to support those aspects for the conditional approval of Dectomax-CA1.

To reduce the risk of antiparasitic resistance and preserve the effectiveness of drugs against other parasites, producers and veterinarians are encouraged to use antiparasitic drugs like Dectomax-CA1 only when medically necessary, in accordance with the product labeling, and as part of a comprehensive parasite management strategy.

According to the U.S. CDC, NWS is typically a disease of livestock but can also affect humans with open wounds; it can also occur in other body cavities with mucus membranes (e.g., nasal passages).

There is no medication to treat NWS; prevention and prompt removal are key.

As of late September 2025, NWS infections had been detected in the Mexican state of Nuevo Leónles, than 100 miles from the Texas border.

The US CDC recently published its Weekly US Influenza Surveillance Report: Key Updates for Week 38 of 2025, which indicates very few influenza cases have been reported this season.

As of late September, the percentage of respiratory specimens testing positive for the influenza virus in clinical laboratories was 0.4%. However, the 2025-2026 flu season generally accelerates in late Fall, peaking during the winter months.

This influenza test data indicates that people are seeing healthcare providers for respiratory illnesses referred to as influenza-like illnesses (fever plus cough or sore throat), not laboratory-confirmed influenza.

The CDC writes that this data may capture respiratory illness visits due to infection with any pathogen that can present with similar symptoms, including influenza, SARS-CoV-2, and RSV. 

According to the World Health Organization (WHO), seasonal influenza vaccination can mitigate the impacts of annual outbreaks by preventing and mitigating the severity of infections.

As of mid-2025, 130 countries reported that seasonal flu shots were available in the public and/or private sector.

In the United States, as of September 30, 2-25, almost every pharmacy is currently offering influenza vaccinations.

Since the beginning of 2025, over 317,000 Chikungunya virus disease cases and 135 related fatalities have been reported in 16 countries/territories in the Americas, Africa, Asia, and Europe.

To help reduce the impact of these mosquito-transmitted Chikungunya outbreaks, various countries have recently approved vaccines. 

Regarding the long-term benefits, one vaccine manufacturer has presented very positive study results.

France-based Valneva SE today reported positive antibody persistence data four years after vaccination with a single dose of its chikungunya vaccine IXCHIQ®. The results confirm a strong and long-lasting antibody persistence across all age groups investigated.

Among the 254 healthy adults still followed in the clinical trial, 95% maintained neutralizing antibody titers well above the seroresponse threshold four years after the single-dose vaccination. The persistence of antibodies in older adults (aged 65+) was comparable to that in younger adults (18-64 years of age) in terms of geometric mean titers and seroresponse rates.

According to the trial protocol, antibody persistence is planned to be collected up to ten years after vaccination.

This study (VLA1553-303) has received funding support from the Coalition for Epidemic Preparedness Innovations and the European Union's Horizon Europe program. It has also collected long-term safety data up to two years, including Adverse Events of Special Interest from the preceding trial and any new-onset Serious Adverse Events.

No safety concerns were reported or identified.

Juan Carlos Jaramillo, M.D., Chief Medical Officer of Valneva, commented in a press release on September 30, 2025, "We are very encouraged by these four-year data, which further reinforce IXCHIQ® 's unique profile and its ability to generate a robust, durable antibody response in both younger and older adults with just a single dose."

"Whether you are a traveler, live in an endemic area, or face an outbreak situation, the prospect of long-term protection from a mosquito-borne disease with a single vaccination is highly valuable, especially in Low- and Middle-Income Countries where vaccine access is often limited."

Chikungunya is a mosquito-borne viral disease spread by the bites of infected Aedes mosquitoes which causes fever, severe joint and muscle pain, headache, nausea, fatigue and rash.

Since the re-emergence of the virus, the European Centre for Disease Prevention and Control has reported that Chikungunya has now been identified in over 110 countries. Between 2013 and 2023, more than 3.7 million cases were reported in the Americas.

While the US and UK governments have previously issued health advisories for ongoing Chikungunya and Measles outbreaks in the Republic of Madagascar in 2025, a Level 3, Reconsider Travel advisory was issued today.

As of September 27, 2025, the US Department of State announced that protests occur throughout the country, and they can turn violent without warning. US citizens should stay in place and avoid areas with protests or demonstrations, as protests may develop quickly, especially after dark. 

Furthermore, the State Department recommends enrolling in the Smart Traveler Enrollment Program to receive important updates and digital alerts from the US Embassy.

Enrolling helps the local embassy contact you or your designated emergency contact in the event of an emergency. For local assistance, the Embassy in Madagascar is located at Lot 207 A Andranoro, Antehiroka, 105 Antananarivo.

Moreover, have a plan to leave in an emergency that does not depend on the US government's help.

'We highly recommend purchasing travel insurance before visiting Madagascar, located off the east coast of Africa, and west of France's Mayotte and Reunion,' writes the US Embassy.

Israel's Ministry of Health today reported that another unvaccinated toddler has died from measles. This is the fifth death since the outbreak began this year, three of which occurred in the past week. 

On September 25, 2025, the Ministry's press release confirmed that 21 measles cases were hospitalized, most of them children who had not been vaccinated. Of these, six children are in intensive care. 

Additionally, the Ministry recommends an additional dose for infants in outbreak zones or before traveling to areas affected by the outbreak. 

Areas currently defined as outbreak zones: Jerusalem, Beit Shemesh, Bnei Brak, Harish, Modi’in Illit, Nof HaGalil, Kiryat Gat, and Ashdod. 

In these zones, you can visit family health centers (Tipat Halav), HMOs, and special measles vaccination stations. No appointment is needed.

In addition to measles, Israel is confronting the spread of poliovirus in 2025.

The U.S. CDC's Level 2, Practice Enhanced Precautions, Global Polio Travel Health Advisory issued on August 4, 2025, included Israel.

The CDC warns international travelers to Israel are at increased risk of exposure to poliovirus and has published updated recommendations for polio vaccinations for children and adults, which should be administered before traveling abroad.

The CDC also recommends various routine and travel vaccines before visiting Israel in 2025. These vaccines are offered in the U.S. at travel clinics and pharmacies.