More frequently asked questions<\/h2>\n
To do those investigations, officials interview people who have been infected to find commonalities, like if they\u2019ve had contact with any backyard chickens, for example. <\/p>\n
\u201cEvery year, we\u2019re having outbreaks associated with people getting young chickens or other water fowl [like ducks],\u201d Hedberg says. \u201cThose practices started to get more common particularly around COVID. People started to get more interested in having their own egg source in their backyard.\u201d<\/p>\n
As public health officials learn about more Salmonella sources, they also ask about them more frequently when investigating cases. So with Salmonella from backyard poultry, Americans\u2019 behavior may be changing, but public health officials are also more attuned to this source.<\/p>\n
\u201cSome things became more common. But we also became more aware that those were potential problems,\u201d Hedberg says, \u201cso they get high on the list of suspicious activities that we wanted to make sure we were asking about.\u201d<\/p>\n
More ingredients means more risk<\/h2>\n
Separately from the backyard poultry-related outbreaks, there\u2019s been a recent wave of recalls for Salmonella contamination in foods from Kroger\u2019s cheese garlic croutons to Williams Sonoma\u2019s white cheddar Fireworks popcorn to Ghirardelli\u2019s powdered drink mixes.<\/p>\n
These cases are all tied to a common source: powdered milk from California Dairies, which is often an ingredient in flavorings. <\/p>\n
Regulatory agencies are often sampling products for outbreaks. But these recalls seem so widespread because the same flavoring ingredients could be in dozens or hundreds of consumer products.\u00a0<\/p>\n
\u201cIf you identify contamination early in the distribution process, then we may see a whole series of recalls occurring,\u201d Hedberg says. \u201cAs they figure out more of what products could have contained that contaminated milk powder, [the scope of recalls] continues to increase.\u201d<\/p>\n
This has happened before; a 2008 Salmonella outbreak was tied to peanut butter and peanut paste. Because that peanut paste was then an ingredient in all sorts of other food products, there ended up being thousands of different products recalled. <\/p>\n
\u201cWe have a lot of food items that contain a lot of ingredients, and the more ingredients you put into food, the more there are opportunities that something with one of the ingredients could be a problem,\u201d he adds. <\/p>\n These are examples of the things that have made Salmonella contamination more visible. But \u201cwhether the problem of Salmonella is increasing or not is more difficult to really put a good answer to,\u201d Hedberg says, \u201cpartly because there are so many different possible sources.\u201d<\/p>\n Salmonella infections have been linked to chicken, pork, beef, turkey, fruit, vegetables, and nuts. But \u201cany food can become contaminated, even processed foods (such as flour),\u201d the CDC notes. <\/p>\n Outside of food, Salmonella has also been linked to lizards (like pet chameleons<\/a>), aquatic invertebrates, farm animals, and wildlife. <\/p>\n And in the background of all this is the fact that climate change is potentially a contributing factor.<\/p>\n \u201cSalmonella are bacteria that grow when it is warmer out, and so you can have enhanced survival in the environment, and more rapid amplification, along certain transmission routes,\u201d Hedberg says.<\/p>\n Broadly, climate change is altering the populations of all sorts of bacteria, and intensifying<\/a> infectious diseases. (As the Earth warms, bacteria also produce more CO2, worsening climate change in a feedback loop.)<\/p>\n A 2025 study<\/a> found that climate change is amplifying pathogen evolution, and even antimicrobial resistance, for everything from cholera to E. coli to Salmonella. <\/p>\n That increase isn\u2019t just from hotter temperatures, though. It\u2019s also exacerbated by heavy rainfall, and climate change is fueling heavier, and more intense rain. <\/p>\n Heavy rain and flooding can spread Salmonella by moving the bacteria around an environment. In an area with a lot of cattle, for example, fresh produce is also often grown nearby.\u00a0<\/p>\n \u201cThe manure from the cattle could move in the environment by way of water,\u201d Hedberg says. \u201cIntense rainfall events can facilitate some of that.\u201d<\/p>\n Generally, climate change disrupts all our normal production cycles, whether because of flooding or even drought. That makes it more challenging for farmers to maintain their usual planting and harvesting schedules, and that opens up room for problems.<\/p>\n \u201cEvery time you start disrupting normal systems, you increase the likelihood that something can go wrong,\u201d Hedberg says. <\/p>\n To mitigate this, Hedberg suggests separating animals from produce. But it will always be a challenge, he adds, \u201cbecause we\u2019re growing fresh produce out in nature, and nature is incredibly complex.\u201d<\/p>\n When it comes to Salmonella broadly, he encourages people to be aware of the potential for infection anytime they bring food into their homes. That means properly preparing, storing, and cooking foods, and washing your hands. <\/p>\n![\"\"](\"https:\/\/images.fastcompany.com\/image\/upload\/f_webp,q_auto,c_fit,w_1024\/wp-cms-2\/2026\/05\/i-2-91545619-salmonella-climate-change.jpg\")
The role of climate change<\/h2>\n
Hand washing, proper food storage, and a funded public health system<\/h2>\n