90-Second Read: Hantavirus and our changing relationship with nature

A few weeks ago, Dutch cruise ship, M/V Hondius, made global headlines for carrying a few infected passengers with Hantavirus disease on board. So far, as per WHO updates, Hantavirus transmission has resulted in 13 cases, confirmed and probable, amongst the passengers and crew members on the ship, resulting in the death of three persons. Elevated average temperatures in West-Central Europe have been associated with more frequent Puumala Hantavirus outbreaks, through high seed production (mast year) and high bank vole densities. Based on existing information, human-to-human transmission is limited and no outbreaks have been observed in the past.

20 species have been known in this genus, of which Andes virus infection causes Hantavirus Pulmonary Syndrome, which is responsible for human-to-human transmission. The bright side is that the virus requires prolonged and close contact for transmission, which became the case with passengers on the ship, triggering the spread in a closed environment of the ship, with limited human interaction and shared indoor spaces. These outbreaks are reminders that personal hygiene and sanitation of living spaces are non-negotiable to safeguard public health. Another significant disease caused by them is hemorrhagic fever with renal syndrome in Asia and Europe, while the former in the Americas.

Before the Covid 19 pandemic fear would have been long forgotten, a possible pandemic threat lingered a new wave of fear across the globe. Though the first person to get infected with the virus on the ship is believed to have acquired the infection from land before boarding. Additional effects can be caused by increased intensity and frequency of extreme climatic events, or by changes in human behaviour leading to a higher risk of human virus exposure. Such anomalous weather, like extreme flooding and drought resulting from El Niño phenomena, wildfires, causes a massive increase in seed dispersal and causes the rodent population to roar and escalate viral infection.

The transmission is high for those engaged in cleaning buildings with rodent infestations or those living in rural settings like fields, farms, or forest areas and carrying out routine activities, where rodents are present copiously. On the other hand, warm winters in Scandinavia have led to a decline in vole populations as a result of the missing protective snow cover. Case isolation, environmental cleanliness and appropriate waste management form the primary line of prevention.