September 4, 2024 – The World gets hotterand the air becomes more humid. And that may be a perfect recipe for more people getting sick from contaminated food Salmonella and other bacteria.
Jeri Barak, PhD, a professor within the Department of Plant Pathology on the University of Wisconsin-Madison, said that as climate change continues to affect our planet, there will probably be “more periods of high humidity,” resulting in more frequent and diverse cases of bacterially infected plants.
This can include the regular produce you purchase at your local food market. If a product is infected, why should we eat it? According to Barak, avoiding infection just isn’t easy, and seemingly healthy plants present in stores could contain salmonella.
“Healthy plants can suffer from water shortages” as climate change increases the frequency of intense rainfall, she said. “Even if the plant is healthy, salmonella can penetrate into the plant's apoplast – the interior of the leaf – where it is protected from ultraviolet light.”
The data reported in the study, together with previous research by the study authors, examine how plant diseases and host infection by a plant pathogen can affect the survival and persistence of Salmonella on or in plants.
The study found that increasing humidity – a result of the warmer atmosphere due to climate change – increases the chances of Salmonella survival. in raw products. The study also found that high humidity could help other bacteria that live in the intestines of animals and humans – such as E. coli and Yersinia, and salmonella – survive on agricultural land and cause infections.
A salmonella infection can cause diarrhea and stomach pain. The bacteria are found in the intestinal tract of animals and are usually transmitted to humans through the consumption of food contaminated with animal feces.
When a sudden infection occurs, enough bacteria can overcome the defenses of your stomach acid and immune system. The bacteria invade and destroy the cells that line the intestinal tract. This makes the body less able to absorb water, causing stomach cramps. The water then leaves your body in the form of diarrhea.
Although the thought of salmonella Images of raw, infected meat or chicken may come to mind, but the most common source of infection is eating contaminated fresh produce. Salmonella can also survive on many different crops and remain in the soil for long periods.
Create the perfect environment for plant diseases
Efforts to control Salmonella on site or before food reaches the consumer have had mixed results.
Ultraviolet (UV) light is used, among other things, to stop germs from multiplying. However, since the germs are protected inside the leaf and are full of water, UV light cannot hinder their growth.
A common threat to leafy vegetable production is Avoid Xanthomonas hortorum pva bacterium that causes spots on lettuce, a disease that affects the quality and yield of lettuce. They are sometimes visible as small dead spots on lettuce leaves a few days after infection and these spots later merge to form larger spots.
First described in 1918 following an outbreak in lettuce fields in South Carolina, bacterial leaf spot threatens lettuce production worldwide. Several outbreaks have occurred over the past century, prompting researchers to study and better understand the interaction between this pathogen and plants.
In this latest study, researchers sought to determine whether the survival of Salmonella in produce is affected by humidity or by the timing of bacterial leaf spot progression.
The researchers found that infection with bacterial leaf spot can affect the success of Salmonella in the plant. If infection with bacterial leaf spot occurs too early, the spread of Salmonella is limited by the plant's defenses. If infection occurs too late, the plant is already so heavily infected that Salmonella has little room to grow and survive.
It is a fascinating, complex, and worrying host-pathogen interaction that threatens food security not only in the United States, but worldwide.
Impact of climate change on food security
Other foods commonly consumed around the world – particularly rice – may be affected by climate change. Successful rice cultivation depends in part on the rice's resistance to potential bacterial diseases that could attack the plants. As conditions improve around the world for bacterial plant diseases to increase, production problems arise and growing conditions deteriorate, leading to price increases and supply shortages.
“Food prices could rise due to climatic factors,” Barak said. “There is less food available… some countries rely on imported food and the producing countries may decide not to export that food because they want to keep it for their own people.”
Areas where we used to produce food may no longer be viable due to climate change, particularly in tropical or subtropical areas. The climate will simply no longer be conducive to food production, threatening food security.
Reducing the risk of foodborne illness
A higher plant disease rate represents a risk factor for contamination with human pathogens such as Salmonella.
Through breeding, plants can be made resistant to these diseases.
“In most cases, we breed resistance when the diseases cause significant crop losses, but we go a step further … as a risk factor for foodborne disease,” Barak said. “Controlling food waste and breeding crop resistance to plant pathogens could be a way to increase food safety.”
In agriculture, antibiotics and chemicals are often overused against bacteria that contaminate food or animal feed. This can cause bacteria to become resistant to antibiotics over time. This is a growing concern for microbiologists and infectious disease specialists around the world, as new and safer solutions are urgently needed before all our usual weapons against bacteria – mainly antibiotics – become ineffective.
In fact, this has been known for years. Many in microbiology have warned against a crisis of antibiotic resistance – the essential explanation for which is the misuse and overuse of antibiotics in animals and plants. In theory, the situation could get even worse as climate change increases the chance of foodborne diseases and requires even greater overuse of antibiotics in our food production.
However, Barak said she has not yet seen any evidence of antibiotic-resistant strains of salmonella. Bacteria, she and her team analyzed data collected by the CDC over the past 10 years National Center for Emerging and Zoonotic Infectious DiseasesThey focused on illnesses, hospitalizations and deaths from salmonella outbreaks.
They found that “the number of hospitalizations increased significantly among people who became ill after eating plant-based products” in comparison with those that consumed meat products, she said. “Whether that was lettuce, nuts, seeds or alfalfa sprouts.”