Since this week, 938 people have been infected with salmonella in 2020. Cases have almost doubled in the last month – 473 people have been ill since the last case report in June, the CDC said.
The presumed culprit in this outbreak is poultry. Public health officials interviewed more than 400 people with salmonella, and 74% said they had contact with chickens and ducks.
Since the first disease was reported in January, the CDC said it had identified 15 multistage outbreaks. So far, three of them found in Kentucky and Oregon have been associated with poultry and their horses.
The CDC did not speculate as to why more people were infected in 2020 than in previous years. Its timeline of reported cases shows that cases began to increase towards the end of March (cases usually appear in the spring, when poultry farming is most popular, the CDC said).
Chickens and ducks can transmit salmonella in their digestive tract, which does not harm them, but can cause diarrhea, fever and painful cramps in people who are exposed to bacteria on the lips or eggs of birds or in their faeces.
Jen Christensen, CNN, contributed to this report.