Moderna advances Hantavirus Vaccine research after cruise ship outbreak raises global concern

US biotechnology company Moderna has confirmed that it is developing a vaccine against hantavirus with the Vaccine Innovation Center of Korea University College of Medicine, known as VIC-K.

The announcement gained attention after a hantavirus outbreak aboard the MV Hondius cruise ship. The ship sailed from Argentina before passengers and crew disembarked in the Canary Islands on May 10.

At least three people died during the outbreak. Several other passengers became seriously ill. Health officials identified the virus involved as the Andean hantavirus, also known as ANDV.

Moderna began research before the outbreak

Moderna did not start the vaccine project because of the recent outbreak. The company and VIC-K launched the partnership in September 2023 under Moderna’s mRNA Access initiative.

The program supports research on emerging infectious diseases. Moderna became globally known during the Covid-19 pandemic for developing mRNA vaccines at high speed.

Following renewed attention on hantavirus, Moderna’s stock rose from $49 on May 7 to $55 the next day. Market analysts said investors reacted positively to the company’s vaccine technology rather than immediate profit expectations.

Understanding Hantavirus risks

Hantavirus is not a new disease. Scientists have studied it for decades. People usually become infected after contact with rodent saliva, urine, or droppings.

The virus causes different illnesses depending on the region. In Europe and Asia, it mainly leads to hemorrhagic fever with renal syndrome. In the Americas, it often causes hantavirus pulmonary syndrome, a severe respiratory disease.

Health experts estimate that hantaviruses cause around 50,000 serious infections worldwide each year.

The Andean hantavirus remains especially dangerous. It is the only known hantavirus strain that can spread between humans through close contact. Authorities linked this strain to the MV Hondius outbreak.

No approved vaccine yet

There is currently no approved vaccine for Andean hantavirus in Europe, the United States, or Latin America. Doctors mainly focus on treating symptoms and managing severe complications.

South Korea remains one of the few countries with a hantavirus vaccination program. The country records between 300 and 400 cases every year, mostly among young adults.

South Korean authorities also consider hantavirus a major future pandemic threat.

However, the country’s existing vaccine, Hantavax, has several limitations. Researchers say it offers inconsistent protection. It also uses older production methods involving animal brain tissue.

These challenges pushed scientists to explore newer technologies such as mRNA vaccines.

Early research shows promise

Under the partnership agreement, Korean researchers provide genetic sequence data from hantaviruses. Moderna then develops the matching mRNA vaccine material.

Early research results have shown promise. In February 2025, a research team led by microbiologist Park Man-sung reported that experimental vaccine doses protected mice from infection.

Despite the progress, experts say the vaccine could still take years to reach the public. Researchers have not yet started human trials because the project remains in the preclinical stage.

Scientists also face another challenge. Hantaviruses vary across regions, making it difficult to create broad protection against multiple strains.

Why mRNA technology matters

Researchers believe mRNA technology offers important advantages over traditional vaccine methods.

The technology does not require scientists to grow live viruses in laboratories. It can also adapt more quickly when viruses change. In addition, manufacturers can scale up production faster during emergencies.

The Covid-19 pandemic demonstrated how quickly mRNA vaccines can move from research to mass production.

Pandemic preparedness remains a priority

The recent outbreak aboard the MV Hondius has renewed discussions about pandemic preparedness. However, the World Health Organization said the outbreak does not signal the start of a larger epidemic.

Health experts still believe proactive vaccine research remains essential. Many scientists argue that developing vaccines before global emergencies occur improves response times and reduces future risks.

Beyond hantavirus, Moderna is also developing mRNA vaccines for avian influenza, noroviruses, and other infectious diseases. Other organizations, including the US Army Medical Research Institute of Infectious Diseases, continue separate hantavirus vaccine research projects.

As global health threats evolve, researchers will continue monitoring whether mRNA technology can help accelerate protection against emerging diseases.