Vaccine News

India is a tropical country undergoing rapid urbanization, making it one of the most affected regions for vector-borne diseases, including Chikungunya Fever.

Epidemics of Chikungunya have been reported since 1963 and continue to occur, with the most recent outbreak recorded in 2025, particularly in the states of Maharashtra and Karnataka.

As of July 14, 2025, India's National Center for Vector-Borne Diseases Control had reported a total of 30,876 Chikungunya cases this year. 

However, according to local news reports, the number of Chikungunya cases in India may be underreported as the rainy season approaches due to issues with diagnostic testing.

Blood tests diagnose Chikungunya. However, since the clinical appearance of both Chikungunya and Dengue is similar, laboratory confirmation is crucial, especially in areas where Dengue is prevalent.

Furthermore, the U.S. CDC says laboratory testing practices for Chikungunya vary significantly among the 100 countries reporting cases.

In Bhopal, the capital city of the Indian state of Madhya Pradesh, a higher positivity rate for Chikungunya was recently detected at 7.02% compared to Dengue's 2.47% in July 2025.

In 2024, Bhopal reported a 16% positivity rate for Chikungunya.

Since millions of international travelers visit India each year, various health agencies have issued vaccination recommendations.

To prevent infections, the CDC recommends that Chikungunya vaccination may be considered for individuals traveling to or moving to India, particularly if they plan to stay for an extended period.

When departing from the United States for India, travel vaccine clinics and pharmacies offer Chikungunya vaccination services for a fee.

As the summer vacation season peaks in late July, international travelers should be aware of where the measles virus is spreading.

According to data from the UK Health Security Agency (UKHSA), 529 laboratory-confirmed cases of measles were reported in England in 2025.

The unfortunate leader is London, with 44% (233 of 529) of these cases.

Other measles outbreaks have been reported in the East of England, the North West, Bristol, Hackney, and Leeds.

To alert all travelers, the U.S. CDC updated its Level 1 - Practice Usual Precautions, Global Measles alert at the end of May 2025.

The UK's NHS says Measles is an infection that spreads very easily in areas such as airplanes, trains, and closed spaces like conference centers.

However, obtaining the MMR vaccine is the best way to prevent infection.

In the United States, MMR vaccines are available at clinics and pharmacies. The CDC recommends vaccination weeks ahead to visiting measles-risk areas in 2025.

The World Health Organization (WHO) published the 55th situation report for the multi-country outbreak of mpox virus (MPXV), which provides details on the global epidemiological situation for mpox, including an update in Africa.

All clades of MPXV continue to circulate in several countries.

On July 11, 2025, the WHO stated that only Türkiye has reported the detection of a new MPXV sub-clade since report #54, in a traveler from the Democratic Republic of the Congo (DRC).

In Africa, community transmission of clade Ib MPXV remains limited to 19 countries. Most countries with previous sporadic importations are currently not reporting active transmission of clade Ib MPXV.

As of July 8, 2025, the countries of Burundi, DRC, Ethiopia, Kenya, Malawi, Rwanda, South Sudan, Tanzania, Uganda, and Zambia are experiencing sustained human-to-human transmission of the virus.

Clade IIb MPXV continues to be reported in West Africa, while Central African countries report both clade Ia and clade Ib MPXV, and East African countries report clade Ib MPXV.

The WHO noted that, despite progress in response activities implemented through collaboration among governments, international partners, and communities, significant funding gaps are threatening the deployment of vaccines.

Approximately 724,000 MVA-BN (JYNNEOS) vaccine doses had been administered in 7 countries, out of the 1.9 million vaccine doses allocated to 13 countries, partly due to funding requirements for shipping to the countries.

Additionally, the DRC had received 1.55 million doses of the LC16m8 vaccine from a bilateral agreement.

In the United States, the JYNNEOS vaccine has become readily available at travel clinics and pharmacies and is recommended for specific international travelers.

The southernmost territory of the United States, situated southwest of Hawaii in the Pacific Ocean, has declared a health emergency related to a surge of dengue fever cases.

As of July 7, 2025, the American Samoa Department of Health issued a travel alert following the confirmation of four imported cases of dengue fever and two locally-acquired cases. The local population is urged to protect themselves from mosquito bites, which are the source of this serious disease.

The government stated that these dengue cases are related to travelers to and from Samoa, a neighboring island.

According to the Samoa Bureau of Statistics, American Samoa welcomed over 200,000 visitors in 2024.

Over the last two years, the U.S. Centers for Disease Control and Prevention (CDC) has reported an increasing number of dengue cases in territories.

The CDC says the dengue virus is endemic and has caused outbreaks in the U.S. territories of Puerto Rico, the U.S. Virgin Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau.

Except for Puerto Rico, dengue vaccines are not available in the continental U.S. or its territories as of 2025.

Within the U.S., the state of Florida reports the majority of dengue cases.

The World Health Organization (WHO) recently published updated clinical guidance for treating four arboviral diseases:  chikungunya, dengue, Zika, and yellow fever.

As of July 4, 2025, this WHO resource is the first that covers all four diseases.

Arbovirus infections have become a growing public health threat, affecting 5.6 billion people.

These diseases are expanding into new regions, where virus-carrying mosquitoes are seldom found, increasing the likelihood of outbreaks beyond tropical and subtropical areas.

The WHO stated that an integrated approach is vital, as these four diseases often present with similar symptoms, especially in the early stages of infection, and multiple arboviruses may circulate simultaneously in certain regions. This makes clinical differentiation particularly challenging, especially when diagnostic testing is not readily available.

These diseases often affect international travelers who lack natural immunity and have not received appropriate immunization with travel vaccines.

Global risk maps are a crucial tool for evaluating the worldwide threat posed by mosquito- and tick-transmitted arboviral diseases. 

The French Republic has been confronted with significant chikungunya outbreaks in various Departments in 2025.

As of July 9, 2025, Sante Publique France reported a total of 25 locally acquired cases of chikungunya in the mainland since May 2025.

Mosquito-transmitted cases have been reported from Provence-Alpes-Côte d'Azur (PACA) (14), Corsica (3), Occitanie (2), Auvergne-Rhône-Alpes (4), Grand Est (1), and Nouvelle-Aquitaine (1).

Located at the far southeastern point of the mainland, PACA's largest city is Marseille, France's third-largest city, with over 800,000 residents, and a tourist favorite destination.

In addition to local cases, France has reported 761 imported cases of chikungunya in the last few months.

Many of these cases are related to international travel to France's Department of Reunion and Mayotte in the southwest Indian Ocean.

In France, as well as in the United States, chikungunya vaccines are commercially offered. Various governments have approved these vaccines and provide a high degree of protection against this mosquito-transmitted disease.

The U.S. CDC recommends vaccination before visiting areas with chikungunya outbreaks, such as the southern regions of France.

With the mosquito season underway in the United States, Florida health authorities have recently reported the third locally acquired case of dengue fever in Brevard County.

As of July 8, 2025, the Florida Department of Health in Brevard County (DOH-Brevard) issued a Mosquito-Borne Illness Advisory, which is scheduled to be effective until mid-September 2025.

DOH-Brevard and Brevard County Mosquito Control have confirmed that they are coordinating surveillance and prevention efforts through both ground and aerial spraying.

Previously, further south along the Atlantic Coast, Miami-Dade County has reported two local cases of dengue this year.

In 2024, 91 locally acquired dengue cases were reported in ten Florida counties, with Miami-Dade leading the way.

As of July 2025, the U.S. Centers for Disease Control and Prevention, Canada, and the United Kingdom have not issued vaccination requirements for visiting Florida this year.

Currently, only Puerto Rico is offering dengue vaccinations in the United States.