Joint pain occurs when one or more joints become inflamed or damaged. Besides physical injuries like falls, collisions, or strenuous activity, unusual joint pain can also be due to several underlying medical conditions.

Influenza, commonly known as the flu, is a widespread viral infection. Symptoms include severe muscle aches, fever, chills, cough, sore throat, runny nose, and sometimes vomiting or diarrhea in children. While most people recover from the flu within two weeks, adults over 65, young children, pregnant women, and those with chronic illnesses like asthma or diabetes face a higher risk of complications.

Covid-19 can cause body aches along with symptoms such as fatigue, fever, chills, headache, cough, sore throat, shortness of breath, loss of taste or smell, runny nose, nausea, vomiting, and diarrhea. Most individuals experience mild to moderate symptoms, alleviated by medication. However, high-risk groups can develop severe complications like blood clots, heart failure, and neurological problems. This group includes adults over 65, unvaccinated individuals, those with chronic diseases, and people with weakened immune systems.

Post-viral complications. Common respiratory viral infections can trigger symptoms that linger for weeks, months, or even years, including joint pain.

Chronic fatigue syndrome (CFS) can develop after a viral illness. Common symptoms include joint pain without swelling, muscle aches, and headaches. Other flu-like symptoms include swollen lymph nodes, difficulty sleeping, cognitive problems ("brain fog"), dizziness upon standing, and post-exertional malaise.

Gout is a form of arthritis caused by elevated uric acid levels in the blood, leading to crystal formation in the joints. This causes sudden inflammation, swelling, and intense pain, often affecting a single joint like the big toe. Gout attacks typically peak within 12 to 24 hours after symptoms begin.

Autoimmune diseases occur when the immune system mistakenly attacks healthy tissues, resulting in joint inflammation and pain. Common autoimmune conditions affecting the joints include:

Rheumatoid arthritis causes joint pain, stiffness, and swelling, treated with medication, therapy, and exercise to prevent damage.

Lupus is an autoimmune disease affecting multiple organs; treatments manage symptoms and prevent flare-ups.

Psoriatic arthritis occurs in patients with psoriasis, causing joint inflammation and treated with medication, therapy, and exercise.

Bao Bao (Times of India).