Multistate (USA) - Outbreaks of Salmonella infections linked to backyard poultry
The Centers for Disease Control and Prevention (CDC) and public health officials in several states are investigating multistate outbreaks of Salmonella Braenderup and Salmonella Montevideo infections linked to contact with backyard poultry.
Public health investigators are using the PulseNet system to identify illnesses that may be part of these outbreaks. PulseNet is the national subtyping network of public health laboratories coordinated by CDC. DNA fingerprinting is performed on Salmonella bacteria isolated from ill people by using techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). CDC PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. WGS gives a more detailed DNA fingerprint than PFGE. WGS performed on Salmonella from ill people in this outbreak showed that they are closely related genetically. This means that the ill people are more likely to share a common source of infection.
As of May 10, 2019, a total of 52 people infected with the outbreak strains of Salmonella have been reported from 21 states shown in the map below by CDC.
A list of the states and the number of cases in each is on the map of reported cases page.
Illnesses started on dates from January 12, 2019, to April 29, 2019. Ill people range in age from less than one year to 60 years, with a median age of 21 years. Fifty-six percent are female. Of 27 people with information available, 5 (19%) have been hospitalized. No deaths have been reported.
WGS analysis of four isolates from ill people predicted antibiotic resistance to amoxicillin-clavulanic acid, ampicillin, cefoxitin, ceftriaxone, or tetracycline. An additional five isolates from ill people did not show evidence of antibiotic resistance. Testing of outbreak isolates using standard antibiotic susceptibility testing by CDC’s National Antimicrobial Resistance Monitoring System (NARMS) laboratory is currently underway. This resistance may affect the choice of antibiotic used to treat some people.
In interviews, ill people answered questions about animal contact in the week before they became ill. Of 33 people interviewed, 23 (70%) reported contact with backyard poultry before becoming ill. Ill people reported buying poultry from various sources, including agricultural stores, websites, and hatcheries.
Backyard poultry from multiple hatcheries are the likely source of these outbreaks. Regardless of where poultry are purchased, these birds can carry Salmonella germs that can make people sick. Backyard poultry owners should always follow steps to stay healthy around their birds.
This investigation is ongoing, and CDC will provide updates when more information becomes available.