Symptoms of a bacterial stomach infection include diarrhea, abdominal cramps, abdominal pain and bloody stools, according to MedlinePlus. Other symptoms include nausea and vomiting. Symptoms of a viral stomach infection or stomach flu include watery and nonbloody diarrhea, vomiting, abdominal pain and low-grade fever, states Mayo Clinic.
Bacterial stomach infections cause the stomach and intestines to become inflamed, and this is what causes symptoms like abdominal cramps and diarrhea, explains Healthline. Severe symptoms include pus in stool, black stool, stomach pain that does not go away after a bowel movement, fever above 101 degrees Farenheit and dehydration, states MedlinePlus. Medical attention is required if symptoms do not get better within two days for children or five days for adults.
Viral stomach infection symptoms often appear within one to three days after the patient gets the infection, and they range from mild to severe, according to Mayo Clinic. Symptoms may last a day or two but could persist for up to 10 days. Other symptoms of viral stomach infections include joint stiffness, muscle pain, poor feeding, weight loss and sweating, according to MedlinePlus.
Viral infections, such as rotavirus, may cause severe dehydration, especially in infants and young children, states MedlinePlus. Medical attention is needed for severe symptoms of a viral stomach infection, such as confusion, dizziness, dry mouth, sunken head soft spots in infants and a sunken appearance to the eyes.