Federal and state health, veterinary and agriculture officials announced an investigation into four multistate outbreaks of human Salmonella infections linked to contact with live poultry.The four outbreaks include Salmonella Enteritidis, Salmonella Hadar, Salmonella Indiana and Salmonella Muenchen.

In the four outbreaks, a total of 181 people infected with the outbreak strains of Salmonella have been reported from 40 states as of June 29, 2015. The number of ill people identified in each state is as follows: Alabama (17), Arizona (3), Arkansas (4), California (3), Colorado (2), Delaware (2), Georgia (4), Indiana (3), Iowa (1), Kentucky (4), Louisiana (2), Maine (2), Maryland (4), Massachusetts (1), Michigan (3), Minnesota (6), Mississippi (13), Missouri (1), Montana (3), Nevada (2), New Hampshire (1), New Jersey (3), New Mexico (2), New York (6), North Carolina (3), Ohio (15), Oklahoma (1), Oregon (5), Pennsylvania (12), South Carolina (10), South Dakota (2), Tennessee (6), Texas (5), Utah (4), Vermont (2), Virginia (11), Washington (6), West Virginia (2), Wisconsin (1), and Wyoming (4).

People infected with the outbreak strains of Salmonella Enteritidis, Hadar, Indiana, or Muenchen, by state

Thirty-three people required hospitalization for their illness.

Epidemiologic, laboratory, and traceback findings have linked these four outbreaks of human Salmonella infections to contact with chicks, ducklings, and other live poultry from multiple hatcheries.

DNA “fingerprinting” is performed on Salmonella bacteria isolated from ill people by using pulsed-field gel electrophoresis, or PFGE. . A total of nine DNA fingerprints (outbreak strains) are included in these four outbreak investigations.

The CDC says backyard flock owners should take steps to protect themselves and their families: Always wash hands thoroughly with soap and water right after touching live poultry or anything in the area where the birds live and roam; Do not let live poultry inside the house and learn about additional recommendations to prevent Salmonella infections from live poultry.

These recommendations are important and apply to all live poultry, regardless of the age of the birds or where they were purchased.

Mail-order hatcheries, agricultural feed stores, and others that sell or display chicks, ducklings, and other live poultry should provide health-related information to owners and potential purchasers of these birds prior to the point of purchase. This should include information about the risk of acquiring a Salmonella infection from contact with live poultry.

Related: Should the Worst Epidemic Yet of Avian Flu Revive Concerns About Urban Homestead Poultry Farming in the US?