The emergence of several cases of hantavirus linked to a cruise ship has reactivated searches about this disease and has caused a wave of alarmist messages on social media. Among the most repeated doubts is a specific question: whether or not there is a vaccine against this virus.
The short answer is that there is currently no vaccine generally approved by international organizations such as the World Health Organization (WHO), the European Medicines Agency (EMA), or the United States Food and Drug Administration (FDA). The main health organizations continue to focus prevention on avoiding contact with infected rodents and controlling possible environmental exposures.
The United States Centers for Disease Control and Prevention (CDC), one of the main international references on infectious diseases, does not include any approved vaccine for the general population in its official information on hantavirus. Its recommendations focus on preventive measures such as ventilating enclosed spaces, safe cleaning, and reducing exposure to rodents and contaminated droppings.
The Spanish Ministry of Health maintains a similar line. In the information disseminated about the virus and about previous outbreaks, the agency insists on prevention and surveillance measures, without mentioning vaccination campaigns or available immunizations for the population.
Vaccines developed in Asia
Despite this, vaccine research and development against certain hantaviruses do exist. The issue is that it is a much more limited and specific scenario than some messages spread on social media are making it seem.
Various scientific studies reviewed and specialized documentation report that China and South Korea have used inactivated vaccines against specific strains of hantavirus. These vaccines have been used locally and in specific contexts, especially against variants associated with hemorrhagic fever with renal syndrome detected in Asia.
However, scientific literature also underlines that these vaccines do not have broad international approval and that doubts remain about aspects such as the duration of protection or their effectiveness against different variants of the virus.
Furthermore, experts recall that these are not vaccines developed specifically for the Andes strain, which is the South American variant that has focused part of the media attention in recent days for being one of the few associated with infections among people in very specific circumstances.
The WHO itself has not announced any vaccine related to the outbreak currently being investigated on the cruise ship MV Hondius. Nor has it proposed immunization campaigns or global health alerts linked to the virus.
A known virus and very different from covid
The comparison with the coronavirus pandemic is one of the points that health organizations and specialists are trying hardest to dismantle. Hantavirus is not a new virus and has been under epidemiological surveillance in different countries for decades.
The main transmission route occurs through contact with infected rodents or with remains contaminated by urine, saliva, or feces. Contagion usually occurs by inhaling particles present in closed or poorly ventilated places where these animals have been.
Cases of transmission between people are exceptional. Specialists explain that they have only been documented in certain variants and in contexts of close and prolonged contact. There is no evidence of sustained community transmission similar to that recorded with SARS-CoV-2 during the pandemic.
The CDC and WHO also maintain that the best prevention tool continues to be reducing environmental exposure. Among the usual recommendations are ventilating closed spaces before entering, using gloves and a mask for potentially dangerous cleaning tasks, and avoiding dry sweeping of dust or droppings.
In parallel, various specialists and fact-checkers have debunked hoaxes claiming that a secret vaccine or miracle treatments against hantavirus already exist. International organizations recall that there is no scientific evidence to support these messages and that the current monitoring of the outbreak does not point to a pandemic scenario.