This case involves a middle-aged male who was a resident of a high rise urban housing project in Arkansas who contracted a rare viral infection shortly after moving in. When the man first moved in to the building, he noticed a number of rodent droppings in the hallway as well as the corners of his closet. He later discovered that the building was infested with both rats and mice, and an ongoing effort to exterminate the vermin had been largely ineffective. Eventually, the man was diagnosed with a viral infection of his respiratory tract that was likely caused by exposure to rodent droppings. It was later discovered that multiple other residents of the building were infected with the same virus.
Question(s) For Expert Witness
- 1. What are the common locations and modes of transmission when this virus is contracted by humans?
- 2. Can you speak to the statistics of virus contraction for this case?
Expert Witness Response E-107469
Yes, mouse droppings may signal past presence of the rodents that carry the virus in question, and of course this multiplies the risk of contracting hantavirus disease. However, hantavirus infection is pretty uncommon, even among persons routinely exposed to mice and their urine. I don’t think anybody knows why the rate of illness is so low, given the millions of persons exposed to the virus each year. It is logically inferred that cleaning would reduce the risk of hantavirus infection, but the incidence of disease is too low for this to be formally known or testable. The question is whether the virus was contracted from the buiding or from some other source. As for whether the best treatment was provided, most cases are not diagnosed until recovery or post-mortem, as the disease initially resembles other more common causes; only symptoms are treated with supportive care. Odds may shift depending on the known circumstances, but I’d reckon it highly unlikely the source of the infection can be known, nor that blame can be rightly assigned except in an emotional way.
Expert Witness Response E-108045
This virus is a hantavirus, which are most often spread through the droppings of mice and rats (at least 430 species). The deer mouse is the most common host for Sin Nombre virus, the most common Hantavirus in the US. It was first identified in the 4 Corners region of the United States, however 31 states have reported being places of exposure to Hantavirus. The vast majority of these cases are in the West. Broadly speaking, anyone (even healthy persons) are at risk of infection with Hantavirus if exposed under the right conditions. The highest risk conditions are enclosed, dark spaces where mice droppings accumulate, dry out, and are allowed to aerosolize. I would consider the building described here to be a potential high risk setting. When working in New Mexico, I investigated the exposure source for an 18 year old male who was diagnosed with Hantavirus Pulmonary Syndrome shortly after his high school graduation. We investigated possible exposures at home, at work, and at known recreational places.