This year, health officials are raising alarms about hantavirus, a disease transmitted by rodents that has already claimed the lives of four people.
While hantavirus is known for its severity—fatal in about 36% of cases—it typically appears in only around 30 cases annually across the US, predominantly in the western and southwestern regions.
However, recent reports show an unusual spike in cases.
Arizona, a notable hotspot, has recorded seven cases and three deaths this year alone.
This is a significant increase compared to the 11 cases reported over the past six years combined (2016-2022).
California is also seeing a concerning trend, with two new cases and one death, including one in a county that hadn’t reported the virus for two decades.
Extreme temperatures and heavy rainfall are believed to be driving this surge.
These conditions force virus-carrying rodents to seek refuge indoors to escape the harsh weather, which increases their chances of coming into contact with humans.
Additionally, the rain promotes plant growth, providing more food for rodents and potentially leading to a rise in their population.
Arizona health officials have stressed that hantavirus is a severe and potentially fatal respiratory illness that isn’t confined to one specific area.
It can be present in various parts of the southwestern US, even if the rodents carrying the virus aren’t visibly noticeable.
How the Virus Spreads
Although rats and mice can carry hantavirus without showing any symptoms themselves, they can spread the virus through their droppings, saliva, and urine.
Humans may contract the virus by inhaling particles from contaminated surfaces.
Initially, infection presents with fever, muscle aches, nausea, and abdominal pain, appearing anywhere from nine to 33 days after exposure.
This can progress to Hantavirus Pulmonary Syndrome, a serious condition where the virus attacks the lungs, causing fluid buildup and severe breathing difficulties.
Unfortunately, there are no specific treatments for hantavirus; management typically involves intravenous fluids and medications to alleviate symptoms.
Regional Impact
Since 1993, Colorado and New Mexico have reported the highest numbers of hantavirus cases, with 119 each.
Arizona follows with 85 cases, while California and Washington have recorded 78 and 59 cases, respectively. In April, Sierra County, California, saw its first case in over 20 years, underscoring the seriousness of the situation.
Officials warned that although hantavirus is rare, it remains highly dangerous, with a fatality rate of approximately one in three.
There are growing concerns that rising temperatures could lead to more frequent diagnoses in new areas as rodents shift their habitats in response to climate changes.