Three travelers have died aboard a cruise ship amid suspicion of hantavirus infection, while another passenger is receiving intensive treatment in South Africa for a confirmed case of the virus.
A 69-year-old passenger is receiving intensive care in South Africa, according to media reports. Two crew members have also fallen seriously ill. “The risk to the general public remains low,” the WHO European Regional Bureau stated in a press release on Monday. “There are no reasons for panic or travel restrictions,” the WHO added. The vessel in question is the Hondius, operated by the Dutch company Oceanwide Expeditions, which was sailing from Argentina to Cape Verde. Currently, 149 passengers and crew members are aboard the Hondius. How and where the travelers contracted the infection remains unclear.
What is Hantavirus?
Hantavirus is a zoonotic disease, meaning it is transmitted from animals to humans. The primary natural carriers of hantaviruses are various species of mice and rats, as well as shrews, moles, and bats. Infected animals shed the virus through their saliva, urine, and feces. Humans typically become infected through contact with the excretions of infected rodents, most commonly by inhaling contaminated dust generated when disturbing dried droppings or nesting material. Infection can also occur by ingesting contaminated particles or by touching the eyes or nose after contact with infected material. The virus can survive in the environment for several weeks; direct contact with infected rodents is not always necessary for transmission, though a bite from an infected animal can also cause infection.
Human-to-human transmission of hantavirus has not been observed in Europe. In South America, a small number of human-to-human transmission cases have been recorded, linked to the Andes virus — a hantavirus strain prevalent in Argentina and Chile. This strain is currently the only known hantavirus variant capable of spreading between people, although a 2021 study indicated that even its human-to-human transmission had not been definitively established.
Symptoms and Consequences
The severity of the illness depends on the hantavirus strain. Strains found in Europe and Asia typically cause a flu-like illness characterized by a high fever (over 38 degrees Celsius or 100.4 degrees Fahrenheit) lasting three to four days, along with headache, abdominal pain, and back pain. Some patients remain asymptomatic. In certain cases, the disease can progress to hemorrhagic fever with renal syndrome (HFRS), which may lead to a drop in blood pressure, kidney dysfunction, and potentially acute renal failure. Mortality rates for HFRS range from less than 1% to 15%, depending on the virus strain, according to a 2023 review published in The Lancet.
Hantavirus strains found in North and South America can cause hantavirus pulmonary syndrome (HPS), characterized by fluid accumulation in the lungs, a drop in blood pressure, and severe respiratory distress. This syndrome is fatal in approximately 30-40% of cases, according to a Lancet study. Recent research also indicates that hantavirus can have lasting health consequences even after an acute infection, increasing the risk of certain types of blood cancer and cardiovascular diseases in patients for years following exposure. The underlying mechanisms of these long-term effects, according to The Lancet, remain unclear.
Treatment and Prevention
Treatment for hantavirus is largely limited to supportive care. Severe cases may necessitate dialysis or mechanical ventilation. Hantavirus vaccines are currently unavailable in Europe, North America, and South America. While vaccines are utilized in China and South Korea, their efficacy has not yet been scientifically confirmed, according to research published in The Lancet.
Research into new approaches for hantavirus treatment is ongoing. Experimental antibody-based therapies derived from survivors have successfully neutralized several hantavirus strains in initial trials. DNA vaccines targeting the Puumala virus have shown promising results in early human trials, with findings published in November 2024.
Source: Deutsche Welle
