The first genome analysis results of the hantavirus that caused a cluster of infections on the cruise ship "MV Hondius" that departed from Argentina have been released. Analyses so far show no major differences from the existing South American Andes virus lineage.
The National Reference Center for Emerging Viral Infections under Geneva University Hospitals in Switzerland on the 8th (local time) released for the first time the full genome sequence of the virus from this infection case via the expert forum virological.org.
The cluster occurred on the polar expedition cruise MV Hondius, which departed from Argentina and was crossing the Atlantic. Of the 147 passengers and crew on board, as of the 8th, eight suspected cases and six confirmed cases have been identified, and three of them have died.
Hantaviruses are typically transmitted through the excreta or saliva of rodents. Infection often occurs when fine particles formed as excreta dry become airborne and enter the respiratory tract. However, the World Health Organization (WHO) said no rats were found on this cruise ship. Accordingly, the WHO suspects the possibility of human-to-human transmission, but it has not yet been determined.
Damien Tully of the London School of Hygiene & Tropical Medicine (LSHTM)–Uganda Virus Research Institute joint research unit said via the U.K. Science Media Centre (SMC), "The currently released genome is broadly similar to hantaviruses transmitted from their natural reservoirs to humans," adding, "There is no indication that a dramatically altered new virus has emerged."
Tully said, "It is closest to the Andes virus lineage identified during the 2018–2019 outbreak in Argentina," and "So far, there is no evidence of genome reassortment or abnormal evolution." Reassortment is a phenomenon in which different viruses exchange parts of their genetic material to create new variants.
Virologist Piet Maes, a professor at the Plotkin Institute of the Université libre de Bruxelles in Belgium, also said, "This virus appears to be a typical Andes virus lineage that was circulating in rodent reservoirs in Chile and Argentina," adding, "No unusual mutations outside the expected range have been observed."
However, experts stressed that caution is needed in interpretation because the currently released data are based on the genome of a single patient.
Tully said, "For now, we cannot determine whether there were multiple spillovers from animals to humans or whether human-to-human transmission continued after a single infection," adding, "Genome analyses of additional patients and animal reservoirs are needed."
He added, "If the patients' viral genomes are nearly identical, that could support the possibility of recent human-to-human transmission, but if the genetic differences are large, each case may be an independent animal infection event."
Meanwhile, the MV Hondius is scheduled to arrive in Spain's Canary Islands on the 10th. Local authorities plan to disembark passengers, then quarantine and test them before sending them back to their home countries. However, amid continued opposition from residents, there is also talk that only the passengers may disembark without the vessel entering port.
These expert opinions were provided through the Korea Science and Technology Media Center (SMCK). SMCK is a nonprofit organization that consolidates the science community and the media, providing expert analyses and verified information on major science issues in Korea and abroad.