What you should know about Hantavirus
Reports of a deadly Hantavirus outbreak aboard a cruise ship travelling across the Atlantic have sparked concern online, with some social media users already comparing the situation to the early days of COVID-19. But public health experts insist that while the virus warrants attention, there is currently no evidence of a looming global health emergency […]
Reports of a deadly Hantavirus outbreak aboard a cruise ship travelling across the Atlantic have sparked concern online, with some social media users already comparing the situation to the early days of COVID-19.
But public health experts insist that while the virus warrants attention, there is currently no evidence of a looming global health emergency or any immediate threat to Nigeria.
The concern followed reports involving the expedition cruise vessel MV Hondius, where at least three passengers reportedly died and several others fell ill after suspected exposure to hantavirus.
The World Health Organisation said the first confirmed patient linked to the outbreak, a 70-year-old Dutch passenger, was most likely infected before boarding the vessel.
According to the WHO, the passenger developed symptoms including fever, headache and mild diarrhoea on April 6, before later suffering respiratory distress and dying aboard the ship on April 11.
Anais Legand, a WHO technical expert on viral haemorrhagic fevers, said the timeline made it clear the infection did not originate onboard the ship.
“The incubation period, the time between infection and the onset of symptoms, is between one and six weeks, but it is typically more like two to three weeks,” she said.
“The man very clearly had exposure before boarding the ship. For this virus, there is no evidence that the disease can be transmitted to someone before symptoms appear.”
WHO officials said the Dutch couple had travelled through parts of South America, including Argentina, before joining the expedition cruise.
Argentine investigators suspect the couple may have contracted the virus while bird-watching near a landfill in Ushuaia, where they were possibly exposed to infected rodents.
WHO Director-General, Tedros Adhanom Ghebreyesus, said eight cases had been identified as of May 6, including three laboratory-confirmed hantavirus infections linked to the outbreak. Three deaths, involving the Dutch couple and a German passenger, have been reported.
Swiss authorities have also confirmed a hantavirus infection in a passenger from the ship who later sought treatment in Zurich, while two confirmed patients and one suspected case were evacuated from the vessel before it departed Cape Verde for Spain’s Canary Islands.
Investigations are ongoing, particularly around the possibility of limited human-to-human transmission involving the Andes strain of the virus.
How Hantavirus spreads and its symptoms
While memories of the coronavirus pandemic have heightened anxiety, experts say hantavirus spreads far less easily than COVID-19.
Hantavirus is not a new disease. It has been known to scientists for decades and is primarily transmitted from rodents to humans. The virus belongs to a family carried by certain species of rats and mice. Human infection usually occurs when people inhale particles contaminated with rodent urine, saliva or droppings. In some cases, touching contaminated surfaces and then the face can also lead to infection.
Unlike COVID-19, which spreads rapidly through respiratory droplets between humans, most hantavirus strains do not easily pass from person to person. According to the WHO, only the Andes strain, mostly found in parts of South America, has shown documented evidence of limited human-to-human transmission, usually involving very close contact.
In a chat with Daily Trust, a resident doctor, Godwin Ekweke, said the current situation should not be interpreted as the beginning of another pandemic.
“Hantavirus infections are generally linked to environmental exposure to infected rodents, not widespread community transmission between humans. This makes the risk profile very different from what the world experienced with COVID-19,” he said.
The symptoms of hantavirus infection can initially resemble many other viral illnesses, making early diagnosis difficult. Patients often begin with fever, headache, muscle aches, fatigue, nausea, vomiting and abdominal pain.
In severe cases, especially in the Americas, the disease can progress into Hantavirus Pulmonary Syndrome, a life-threatening condition marked by breathing difficulties and fluid accumulation in the lungs.
In Europe and Asia, some hantavirus strains are more commonly associated with kidney complications, a condition known as haemorrhagic fever with renal syndrome.
Experts say the cruise ship outbreak appears alarming mainly because it occurred in a confined environment and involved older passengers, some of whom may have had underlying health conditions.
The WHO says there is currently no evidence of the kind of widespread onboard transmission seen during COVID-19 cruise ship outbreaks in 2020.
A physician, Dr Chukwudi Ifeanyi, said the public must avoid panic and misinformation.
“One of the major lessons from COVID-19 is that fear spreads faster than facts. People hear the word ‘virus’ and immediately assume another pandemic is starting. But every virus behaves differently,” he said.
“The prevention strategy is therefore more environmental and hygiene-based. Control rodents, maintain sanitation, store food properly, and avoid inhaling dust in rodent-infested places,” he added.
Nigeria’s preparedness and public advisory
In Nigeria, there have been no officially confirmed hantavirus outbreaks. However, experts acknowledge that rodent-borne diseases remain a concern because of widespread sanitation challenges, overcrowded settlements, poor waste disposal systems and periodic flooding in some communities.
Nigeria already battles diseases such as Lassa fever, another rodent-borne viral illness endemic in parts of the country. Because of this, many infectious disease specialists say the country’s existing Lassa fever surveillance systems may provide a useful foundation if hantavirus cases ever emerge.
The Nigeria Centre for Disease Control had not responded to enquiries as of press time. However, infectious disease experts familiar with the country’s preparedness systems say Nigeria is better positioned today than it was before the COVID-19 pandemic.
Dr Gbenga Owu said the pandemic forced significant improvements in disease surveillance, emergency coordination, laboratory capacity and public awareness.
“COVID-19 exposed many weaknesses globally, including in Nigeria, but it also accelerated investments in public health systems. Today, there is stronger coordination between laboratories, surveillance officers, emergency response teams and state health authorities,” he said.
According to him, Nigeria’s experience managing outbreaks such as Ebola virus disease, COVID-19, cholera, mpox, diphtheria and recurrent Lassa fever has improved institutional readiness for infectious disease emergencies.
Still, he warned that preparedness does not eliminate risk entirely.
“We must not become complacent. Preparedness requires continuous investment, especially in diagnostics, border surveillance, healthcare workforce training and risk communication,” Dr Owu said.
“There is always the risk of underdiagnosis when diseases present with common symptoms. That is why surveillance systems and laboratory confirmation are very important,” he added.
He added that healthcare workers should remain alert, especially when patients report exposure to rodent-infested environments or recent travel to affected areas.
Experts also say international travel means Nigeria cannot completely dismiss the possibility of imported cases, even if the overall risk remains low.
However, virologists stress that hantavirus is far less contagious than airborne viruses like coronavirus or influenza.
For ordinary Nigerians, experts say prevention measures are relatively straightforward. Homes and workplaces should be kept clean and free from rodent infestation. Food items should be stored in sealed containers, refuse should be disposed of properly, and holes or cracks that allow rodents into buildings should be sealed.
People cleaning abandoned buildings, warehouses or dusty storage areas are advised to wear gloves and masks if rodent contamination is suspected. Sweeping dry rodent droppings can release infectious particles into the air, increasing the risk of inhalation.
Experts also caution against handling dead rodents with bare hands.
Medical attention should be sought immediately if someone develops persistent fever, body weakness, breathing difficulty or severe flu-like symptoms after possible rodent exposure or travel to affected regions.
“Hantavirus can deteriorate very rapidly once respiratory symptoms begin. Early medical intervention improves survival chances,” Dr Owu warned.
Several viral posts have inaccurately described hantavirus as “the next COVID” or suggested that global lockdowns could soon return. Experts insist such claims are not supported by current evidence.
The WHO has not declared any international public health emergency related to hantavirus, and health agencies continue to describe the risk of widespread transmission as low.
The agency’s investigations into the MV Hondius incident are focused mainly on identifying exposure pathways, monitoring close contacts and ensuring proper medical management of affected individuals.
For now, specialists say the most appropriate response is calm vigilance rather than fear.
“There is no reason for panic in Nigeria at this stage. But there is every reason to strengthen sanitation, surveillance and public health education because these measures protect against many diseases, not just hantavirus,” Dr Yusuf Bello said.
While global health authorities continue to monitor the situation, specialists insist there is currently no basis for panic or comparisons to the COVID-19 pandemic.