Hepatitis B is a serious liver infection caused by the hepatitis B virus. The virus attacks the liver and can cause both acute and chronic disease. Some people clear the virus on their own, while others develop long-term infection that may lead to severe liver damage. Hepatitis B spreads through contact with infected blood or certain body fluids. Chronic hepatitis …

Hepatitis A is a contagious liver infection caused by the hepatitis A virus. The virus leads to inflammation of the liver, which can affect how well the liver works. Hepatitis A is usually spread through close contact with an infected person or by consuming contaminated food or water. Unlike other types of hepatitis, hepatitis A does not cause long-term liver …

Hantavirus pulmonary syndrome is a rare but severe viral illness that primarily affects the lungs and can be life-threatening. It is caused by infection with hantaviruses, which are carried by certain rodents. Humans become infected through contact with rodent urine, droppings, or saliva, especially when these materials become airborne. The disease progresses rapidly and requires immediate medical attention. Symptoms Symptoms …

A hangover is a collection of unpleasant physical and mental symptoms that occur after consuming excessive amounts of alcohol. It typically develops as blood alcohol levels return to zero and can affect overall well-being, daily functioning, and productivity. Hangovers vary in severity depending on the amount of alcohol consumed, individual tolerance, hydration status, and general health. Symptoms Hangover symptoms usually …

Hand-foot-and-mouth disease is a common viral illness that mainly affects infants and young children, though adults can also become infected. It is most often caused by enteroviruses, particularly coxsackievirus. The condition is usually mild and self-limiting, but it is highly contagious and spreads easily in childcare settings, schools, and households. Symptoms Symptoms typically appear 3 to 6 days after exposure …

A hamstring injury is a strain or tear of one or more of the hamstring muscles located at the back of the thigh. These muscles play a key role in bending the knee and extending the hip. Hamstring injuries are common in athletes and physically active individuals, particularly in sports that involve sprinting, jumping, or sudden stops and starts. The …

Hammertoe and mallet toe are common foot deformities in which one or more toes bend abnormally due to muscle and tendon imbalance. Hammertoe typically affects the middle joint of a toe, causing it to bend downward, while mallet toe affects the joint closest to the tip of the toe. These conditions often develop gradually and may become fixed over time …

Trichotillomania, also known as hair pulling disorder, is a mental health condition in which a person feels a strong urge to pull out their own hair. The behavior is often difficult to control and can lead to noticeable hair loss on the scalp, eyebrows, eyelashes, or other parts of the body. People with trichotillomania may pull hair as a response …

Helicobacter pylori infection is a common bacterial infection of the stomach caused by Helicobacter pylori. The bacteria damage the protective lining of the stomach and duodenum, leading to inflammation and increasing the risk of ulcers. Many people with H. pylori infection have no symptoms, but long-term infection can result in serious digestive conditions if left untreated. Symptoms Many individuals with …

Periodontitis is a serious gum infection that damages the soft tissue and can destroy the bone that supports the teeth. It usually develops from untreated gingivitis, a milder form of gum disease. If not treated properly, periodontitis can lead to tooth loosening or tooth loss. The condition occurs when bacteria accumulate in dental plaque and cause inflammation in the gums. …