Diarrhea, fever, chills and body aches

A stomach or bowel infection can trigger loose stools while the immune response causes fever, chills and muscle aches. Influenza and COVID-19 can also cause body aches and fever; diarrhea may occur alongside their respiratory symptoms. Travel or mosquito exposure makes illnesses such as malaria or dengue fever relevant to discuss with a clinician. Brucellosis can be considered after particular animal or unpasteurised dairy exposures. Fibromyalgia and hypothyroidism may cause aches or tiredness, but they do not usually explain a sudden febrile diarrheal illness.

Take frequent small sips of water or an oral rehydration drink. Continue light foods if tolerated, such as rice, soup, toast or bananas, and rest. Wash hands carefully and avoid preparing food for others while diarrhea continues. Record the temperature, stool frequency, recent foods, travel, medicines, sick contacts and mosquito or animal exposures. Avoid anti-diarrheal medicine if there is blood in the stool or a high fever unless a clinician advises it.

Seek urgent medical help for confusion, fainting, severe weakness, trouble breathing, severe or persistent abdominal pain, blood or black stool, repeated vomiting, or inability to keep fluids down. Arrange prompt assessment if fever persists, urine becomes very dark or infrequent, or symptoms follow travel to a malaria-risk area. Children, older adults, pregnant people and people with weakened immunity can become dehydrated quickly and should seek advice early.

Could an infection linked to my food, travel, medicines or contacts explain this pattern? Do I need testing for a respiratory, gastrointestinal or mosquito-borne illness? Which fluids and medicines are suitable for me? What changes should prompt emergency care?