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Any Foodborne Transmission Among Hantavirus, Swine Flu or WNV?

Not a lot, but some

Mangoes are likely responsible for the ongoing Salmonella Braenderup outbreak and Cantaloupes are almost certainly the source of the recent Salmonella Typhimurium outbreak, but what roles do food and water play in spreading Hantavirus, swine flu and West Nile Virus?

None of the three are typically thought of as foodborne diseases, but that does not tell the whole story.


For example, the federal Centers For Disease Control and Prevention (CDC) in Atlanta reports that people can contract Hantavirus Pulmonary Syndrome if they eat food contaminated by urine, droppings or saliva from an infected rodent.

That might not happen at your house. Hantavirus infections typically occur in people who are camping, hunting or doing other outdoor activities. This year 10,000 people who visited Yosemite National Park have been warned about Hantavirus because they may have stayed in the park’s Curry Village an area containing permanent tent-like structures.

Three confirmed and one possible case of Hantavirus have been linked to that location.

CDC says many Hantavirus victims probably touch something contaminated with rodent urine, droppings, or saliva and then touch their own nose or mouth. Rodent bites would also do, but those are rare.

Airborne transmission is also likely from tiny droplets of urine, rodent droppings and nesting material get into the air.

Any number of rodents — from deer mice to cotton rats — can spread the virus. CDC has tracked Hantavirus in the U.S. since 1993, the year when attention was first focused on the virus after unexplained deaths began occurring in the Four Corners area of the American Southwest.

The exposure of Yosemite’s many park visitors to Hantavirus this year does not mean that anything extraordinary is going on. Through early July, only 15 new confirmed cases had been recorded since last year when the total count since 1993 stood at 587.

The mean age for a Hantavrirus victim from 1993 to 2011 was 37, with two out three being men from the Four Corners states of Utah, Arizona, Colorado and New Mexico. California and Texas had the most cases.

Swine Flu

More than 300 variant influenza viruses have now been recorded in the U.S. Most of these “swine flu” viruses have been found in Indiana and Ohio, which recently experienced the first deaths. The term “variant” means they are similar to viruses circulating in swine.

The current U.S. outbreak of swine flu involves the H3N2 Influenza A Variant Virus. In addition to the one death, 15 of the 288 people infected required hospitalization.

CDC reports that swine flu has not been shown to be transmissible to people through eating properly handled and prepared pork (pig meat) or other products derived from pork. Key to proper preparation is cooking pork to 145 °F throughout.

West Nile Virus (WNV)

About 30,000 Americans have suffered from West Nile Virus since 1999. Unless you count one case where a nursing mother with West Nile Virus gave it to her baby, WNV is not much of a foodborne disease.

But standing water is another story. Mosquitos do their breeding in standing water, bird baths or pets’ water bowls. Breeding areas mean more mosquitos and more WNV-carrying mosquito bites.

Dr. Lyle Petersen, CDC’s director of the division of vector-borne infectious diseases, says cases of West Nile Virus are on the rise.

“As of August 28th, 2012, a total of 48 states have reported West Nile virus infections in people, birds or mosquitoes. Only Alaska and Hawaii have reported no West Nile virus activity. Forty-three states have reported at least one human case of West Nile virus disease.”

CDC received reports of 1,590 cases of West Nile virus disease in people, including 66 deaths, Petersen told an Aug. 29 press briefing.

“Of these, 889 (56 percent) were classified as neuroinvasive disease, such as meningitis or encephalitis; and 701 (or 44 percent) were classified as non-neuroinvasive disease. These numbers represent a 40 percent increase over last week’s report of 1,118 total cases, 629 neuroinvasive disease cases, and 41 deaths.

“The 1,590 cases reported thus far in 2012, is the highest number of West Nile virus disease cases reported to the CDC through the last week in August since West Nile virus was first detected in the United States in 1999. More than 70 percent of the cases have been reported from 6 states, which in descending order are Texas, South Dakota, Mississippi, Oklahoma, Louisiana, and Michigan. Nearly half of the cases are from Texas.”

© Food Safety News
  • husna aijaz

    The rodents in Yosemite National Park are not “exclusively” characterized to transmit the deadly HPS virus. If pest control measures are not adopted around food distribution facilities, it is possible to breathe in this air-borne virus resulting in life-threatening illness that can lead to death.
    It is another story that many cases are not accurately diagnosed or have been misdiagnosed.
    The following article provides in-depth information on Hantavirus infection.