“It’s not a new Covid”, emphasizes .
Although the crisis on the MV Hondius cruise ship, which today set sail for the Netherlands, has sparked lively concerns, rekindling memories of the 2020 coronavirus pandemic, there are many differences between the two diseases, experts say. What are they?
Origin
Covid-19 is an infectious, viral disease caused by the Sars-CoV-2 coronavirus, which emerged in China in late 2019. Was it spread from animals to humans in the Wuhan market, or did it come from a scientific laboratory in the city, from a mutated virus that was being experimented on? Both hypotheses have been formulated, but most scientists support the first.
This virus was isolated in early January 2020 and on 11 March 2020 the World Health Organization announced that the Covid-19 outbreak was now a “pandemic”. The dead were in the millions (up to 20, according to the WHO), and the pandemic caused repeated shocks to the global economy.
Handavirus, whose name comes from the Korean river Handan, since the first epidemic was recorded there, during the Korean War (1950-53), is a virus that exists on all continents, but especially in Asia and Europe. Scientists are monitoring the zones where it is endemic.
Transmission and symptoms
Hantaviruses are transmitted to humans mainly through the urine, feces and saliva of infected rodents. The main mode of transmission is inhalation of contaminated faecal dust.
The only one of the 30 strains of handavirus known to be transmitted from person to person is the Andean strain, which was found among sick cruise ship passengers. The incubation period ranges from one to six weeks. In contrast, in Covid-19 the first symptoms appear on average 7-10 days after infection.
Although the transmission of Andean hadavirus from person to person is through the respiratory tract, special conditions are required for someone to become infected: close contact, sexual intercourse or the vulnerability of the person who will be exposed to it, explained Virginie Sauvage of the Pasteur Institute, who is in charge of the National Reference Center for hadaviruses in France.
According to the Institut Pasteur, “the period of highest risk transmission” for hadavirus is before symptoms appear. The most exposed are people who come into very close contact with the patient (e.g. through sexual intercourse) or are with him in closed spaces (bedroom, car).
Americas hantaviruses can cause respiratory and cardiac distress, as well as hemorrhagic fevers, but Covid-19 is exclusively a respiratory disease that can cause fever, cough, shortness of breath, headache, body aches, fatigue, diarrhea, loss of smell and taste.
Higher mortality, lower pandemic risk
A virus that would kill “50% of the population, would decimate the world very quickly, but that would deprive it of the ability to spread,” said Raul Gonzalez Itig, a biologist at the National Agency for Scientific Research in Argentina, a country that recorded 11 deaths from hantavirus between 2018-19. The fatality rate of Andean hedavirus is approaching 40% and “death occurs quickly,” he explained, stressing that “isolating patients without delay breaks the chain of transmission.”
“Everything happens faster: a single person transmits it, ten become infected and, without proper treatment, die. Therefore, the risk of a hadavirus pandemic is much lower,” he summarized. In contrast, Covid-19 infected thousands of people before the deaths began to pile up.
There is no vaccine
There is no specific treatment and no vaccine for hadavirus, infectious disease specialist Vincent Ronen told AFP.
But “the sooner the disease is diagnosed, the better the prognosis” for sufferers, Sauvage explained. If someone develops severe pulmonary symptoms, it is necessary to receive respiratory assistance, for example to be intubated. If he has kidney failure, he may need dialysis.
In Covid-19, treatment consists of treating the symptoms (eg with paracetamol) but some vulnerable people may need to be given antivirals.
As for vaccines, trials have been done for some strains of hadavirus but their effectiveness has not yet been proven for all types, Ronen said.
For Covid-19, vaccines were developed in record time, in the middle of the pandemic. Their effectiveness and safety have since been documented, based on the billions of vaccinations given around the world.
