Immune and infectious diseases Archive

Lingering ulcers can signal more than simple canker sores. Learn about possible triggers, related conditions, and who should evaluate you.

It’s possible for people of any age to contract sexually transmitted infections (STIs). STIs are sometimes symptom-free, making them easy to miss, pass along, and ignore.

In this quiz, test your knowledge of which foods can nourish your body and help prevent disease, and which foods can play an inflammatory role in the body.

A 2026 study suggested that getting a high-dose flu shot may reduce older adults’ risk of developing Alzheimer’s disease compared with a standard-dose flu shot.

Humira can control autoimmune disease, such as psoriatic arthritis. But it also alters immune defenses. Learn about infection, cancer, and other potential long‑term risks.

Warm, damp shoes can harbor fungus well after a skin infection clears. Fresh socks, antifungal powder, rotation, and retiring old shoes are all important.

An elevated lymphocyte count usually indicates a simple viral illness. Less often, it could indicate a blood cancer. How the number is calculated shapes what it may mean.

Your immune system constantly defends you from harmful germs like bacteria and viruses, but your body also hosts trillions of helpful microbes-your microbiome-that live on your skin, in your gut, and elsewhere. These "good" germs help digest food, make vitamins, protect you from harmful invaders, and help regulate inflammation.

Sinusitis occurs when blocked sinuses cannot drain and the backed-up mucus gets infected. The simplest and often most effective treatment is daily nasal irrigation. It can also help to drink a lot of water, inhale steam, and sleep with the head elevated.

The Epstein-Barr virus that causes mononucleosis (mono) usually infects people during their childhood or the teenage years. The virus stays with people for life.