Salmonella uses a variety of dynamic techniques to impair and confuse host immune cells, including its ability to induce phagocytosis in certain white blood cells, which allows the organism to gain entry into cells more effectively. Login Toggle navigation Search. April 8, Share This. Though pathogenic serotypes can be very genetically similar , they can have different abilities to cause severe disease. Some serotypes cause a few days of mostly self-limiting illness, whereas others cause life-threatening complications.
It is not well understood how specific serotypes alter host immune response and modulate bacterial virulence.
Serotypes can be further divided into typhoid and non-typhoid serotypes, based on their ability to cause typhoid or paratyphoid fever , a type of severe S. Typhoid and paratyphoid strains are typed using O and H antigens, but also by their Vi Virulence antigens. The Vi antigen is a capsular antigen that contributes significantly to virulence, which may partially explain the disparity in disease severity between typhoid and non-typhoid strains.
Typhoid Salmonella infections are more likely to be life-threatening , causing high fevers, headaches, constipation or diarrhea, and rose spots —patches of red discoloration on the skin where bacterial emboli are present.
Salmonella undermines non-phagocytic immune cells too, by inducing reactive oxygen species ROS production from human neutrophils. Salmonellosis sal-mohn-el-OH-sis is a bacterial disease caused by Salmonella. Although Salmonella is most often spread when a person eats contaminated food, the bacteria also can be passed between people and animals. Many different animals and pets can carry these germs.
Animals known to commonly spread Salmonella to humans include. Animals become infected with Salmonella through their environment, by eating contaminated food, or from their mothers before they are even born or hatched.
Salmonella is naturally in the intestines of many different animals. Animals with Salmonella shed the bacteria in their stool which can easily contaminate their body parts fur, feathers, or scales and anything in areas where these animals live and roam terrarium or aquarium, chicken coop, pen or fencing, countertops, sinks, etc.
It is important to know that many animals can carry Salmonella and still appear healthy and clean. People can get a Salmonella infection if they do not wash their hands after contact with animals carrying Salmonella or their environment, such as their bedding, food, or tank water.
Pet food and treats that may be contaminated include dry dog or cat food , dog biscuits, pig ears, beef hooves, and rodents used to feed reptiles including frozen feeder rodents.
Anyone can get sick from Salmonella , but some people are more likely than others to get salmonellosis. People who are more likely to get salmonellosis include:. Who Is at Risk for Salmonella Infections? People at risk for more serious complications from a Salmonella infection include those who: are very young, especially babies have problems with their immune systems such as people with HIV take cancer-fighting drugs or drugs that affect their immune system have sickle cell disease have an absent or nonfunctioning spleen take chronic stomach acid suppression medicine In these higher-risk groups, most doctors will treat an infection with antibiotics to prevent it from spreading to other parts of the body.
How Are Salmonella Infections Treated? Can Salmonella Infections Be Prevented? Here are some other ways to protect yourself from Salmonella infections: Cook food thoroughly. Salmonella bacteria are most commonly found in animal products and can be killed by the heat of cooking. Don't serve raw or undercooked eggs, poultry, or meat. Microwaving is not a reliable way to kill the bacteria.
Handle eggs carefully. Because Salmonella bacteria can contaminate even intact and disinfected grade A eggs, cook them well and avoid serving poached or sunny-side up eggs with runny yolks. Avoid foods that might contain raw ingredients. Caesar salad dressing, the Italian dessert tiramisu, homemade ice cream, chocolate mousse, eggnog, cookie dough, and frostings can contain raw eggs.
Unpasteurized milk and juices also can be contaminated with Salmonella. Some researchers think typhoid fever is what killed Alexander the Great — so clearly humans have been living with Salmonella for thousands of years. The good news is that you are very unlikely to find S. Typhi in your house — especially if you live in the United States — and S. The bad news is that there are many other types of Salmonella that DO cause salmonellosis — and they can be found on all kinds of different things.
In alone, salmonellosis outbreaks investigated by the CDC included multistate outbreaks caused by: a strain called S. Bredeney in peanut butter ; S. Typhimurium in hedgehogs! Braenderup in mangoes ; and both S.
Newport and S. Typhimurium in cantaloupes. Salmonella bacteria have evolved over thousands of years, changing to give themselves a better chance of surviving in a wide range of environments.
0コメント