This is a very common symptom that usually means sickness in the stomach. This is one of the first symptoms to appear and, in most cases, is accompanied by a repulsive sensation for the food and the impulse to vomit.
5. Fever and chills
The patient usually has a mild or moderate fever; however, it is not a constant symptom because it can be caused by some bacteria and viruses, but it is less common in parasitic infections.
The fever is produced by the immune system reaction to the toxin or pathogen, which tries to counteract their negative effects on the organism. When the temperature is higher than 38.6 °C or 101.5 °F, it is important to visit a doctor.