A 2023 Swiss study has resurfaced in the wake of a deadly hantavirus outbreak aboard the cruise ship MV Hondius, revealing that the Andes strain of the virus can linger in human semen for nearly six years after infection. The research, published in the journal Viruses, raises the possibility of sexual transmission long after symptoms subside, though experts caution that more data is needed to assess the actual risk.
The outbreak on the Dutch-flagged vessel killed three passengers and infected several others, with a small number of Americans either testing positive or under monitoring in the U.S. Global health officials stress that the Andes strain, the only known form of hantavirus capable of person-to-person transmission, is not expected to trigger a pandemic. However, its mortality rate can reach up to 40 percent, making it one of the deadliest known pathogens.
The study, titled "Presence and Persistence of Andes Virus RNA in Human Semen," examined a 55-year-old man who had survived severe complications from Andes hantavirus nearly six years earlier. Researchers detected viral RNA in his semen, even though the virus was no longer present in his blood or urine. Based on this, they concluded that sexual transmission could be possible for up to 71 months after initial infection.
Scientists note that the persistence of pathogens in the male reproductive system is not unique. Viruses like Ebola and Zika have also been shown to remain in semen and, in some cases, be transmitted sexually. The findings add to a growing body of evidence that certain viruses can hide in immune-privileged sites, complicating efforts to control outbreaks.
The recent cruise ship deaths have fueled concerns about overreaction, with some experts linking heightened anxiety to post-COVID psychological trauma. The Centers for Disease Control and Prevention (CDC) is monitoring 41 individuals for hantavirus exposure but has declined to impose quarantine orders, citing low transmission risk. This has sparked debate about the adequacy of public health measures, especially given the virus's high lethality.
The study's authors emphasize that more research is needed to determine whether the presence of viral RNA in semen actually leads to infectious virus capable of transmission. They also call for further investigation into the duration of viral persistence and potential sexual transmission routes, particularly in the context of outbreaks.
Health officials continue to advise caution for those exposed to hantavirus, particularly in regions where the Andes strain is endemic. The MV Hondius outbreak has prompted renewed scrutiny of cruise ship sanitation protocols, with outbreaks of norovirus and hantavirus rising in the industry. While the risk of a global spread remains low, the study underscores the need for vigilance and further research into the virus's long-term effects.
