The authorities are following with special care the evolution of the hantavirus outbreak on the MV Hondius cruise ship that is already heading to the Canary archipelago. The Government of Spain has authorized the ship near the islands while insisting that the risk is low after confirming five cases of hantavirus and three suspects as of this Thursday.
But even though this outbreak has sparked a crisis that has led the WHO to appear at a press conference and the European Union to coordinate with Spain, the Netherlands, Germany and other countries (149 passengers of 23 different nationalities were traveling on the cruise), the truth is that . The variant that has caused the outbreak, the Andes virus, too.
Proof of this is that 33 years ago, in 1993, The US recorded one of the deadliest episodes due to a hantavirus outbreak. In that case (it was later learned) the trigger was another variant with a somewhat more sinister name: the “nameless virus.” The abundant rains from El Niño caused vegetation to grow in the area of the US known as “The Four Corners”, as it is the corner where the borders of Arizona, New Mexico, Utah and Colorado border.
The more vegetation, the more food, and the more food, the more deer mice, a species native to North America and a natural reservoir of this variant of the hantavirus (unnamed virus). This variant does not usually lead to infections between humans, but it caused 33 cases of hantavirus pulmonary syndrome, of which 17 led to death. In the entire US that year there were 48 cases and 27 died. A fatality of 52%.
How is it possible, if the American variant does not cause contagion between humans? For a simple reason: the population of deer mice grew exponentially that year due to the abundant vegetation, and this hantavirus is only transmitted to humans who have been in contact with excrement or urine of these animals. It was a dark year in which many cadres became infected from cleaning barns or camping outdoors.
The Andean hantavirus does spread between humans
Although at first it was assumed that what was happening on the MV Hondius were conditions diagnosed by zoonosis (infection due to coming into direct contact with carrier animals), it is now known that behind everything is the Andes variant that can be spoken of as contagion between humans. This contagion was rare, but a scientific study shows that it can cause “super-spreaders.”
He paperwho has consulted The Countrytells how an outbreak analyzed in several parts of Argentina began after three people with symptoms went to social events. Until then, it was thought that the hantavirus was spread through very close, hospital and sexual contacts. The study of that outbreak eight years ago in South America reveals that the Andes strain can cause superspreaders. That is, each human with a viral load can infect the virus to at least 2.12 people on average.
That ’93 outbreak in the US also led to the discovery of hantavirus pulmonary syndrome (HPS). It was also the discovery of hantavirus in rodents that was transmitted to humans in the West: until then this phenomenon was only seen in some areas of Asia. In the following years, more hantaviruses that cause HPS were discovered. The Andes virus was identified in 1995 and a year later, in ’96, person-to-person transmission was identified in an outbreak in El Bolsón, also in Argentina.
Although there is no vaccine or cure, there is medical treatment that significantly reduces the fatality rate. After all, compared to what happened in 2020 with the appearance of SARS-CoV-2 that caused covid-19, science is already 30 years ahead to these viruses.
