Around 85% of people infected with<unk>  virus experience symptoms, typically beginning with a sudden high fever above . The fever is soon followed by severe muscle and joint pain. Pain usually affects multiple joints in the arms and legs, and is symmetric – i.e. if one elbow is affected, the other is as well. People with<unk>  also frequently experience headache, back pain, nausea, and fatigue. Around half of those affected develop a rash, with reddening and sometimes small bumps on the palms, foot soles, torso, and face. For some, the rash remains constrained to a small part of the body; for others, the rash can be extensive, covering more than 90% of the skin. Some people experience gastrointestinal issues, with abdominal pain and vomiting. Others experience eye problems, namely sensitivity to light, conjunctivitis, and pain behind the eye. This first set of symptoms – called the "acute phase" of<unk>  – lasts around a week, after which most symptoms resolve on their own. Many people continue to have symptoms after the "acute phase" resolves, termed the "post-acute phase" for symptoms lasting three weeks to three months, and the "chronic stage" for symptoms lasting longer than three months. In both cases, the lasting symptoms tend to be joint pains: arthritis, tenosynovitis, and/or bursitis. If the affected person had pre-existing joint issues, these tend to worsen. Overuse of a joint can result in painful swelling, stiffness, nerve damage, and neuropathic pain. Typically the joint pain improves with time; however, the chronic stage can last anywhere from a few months to several years. Joint pain is reported in 87–98% of cases, and nearly always occurs in more than one joint, though joint swelling is uncommon. Typically the affected joints are located in both arms and legs. Joints are more likely to be affected if they have previously been damaged by disorders such as arthritis. Pain most commonly occurs in peripheral joints, such as the wrists, ankles, and joints of the hands and feet as well as some of the larger joints, typically the shoulders, elbows and knees. Pain may also occur in the muscles or ligaments. In more than half of cases, normal activity is limited by significant fatigue and pain. Infrequently, inflammation of the eyes may occur in the form of iridocyclitis, or uveitis, and retinal lesions may occur. Temporary damage to the liver may occur. People with<unk>  occasionally develop neurologic disorders, most frequently swelling or degeneration of the brain, inflammation or degneration of the myelin sheaths around neurons, Guillain–Barré syndrome, acute disseminated encephalomyelitis, hypotonia (in newborns), and issues with visual processing. In particularly rare cases, people may develop behavioral changes, seizures, irritation of the cerebellum or meninges, oculomotor nerve palsy, or paralysis of the eye muscles. Newborns are susceptible to particularly severe effects of<unk>  infection. Signs of infection typically begin with fever, rash, and swelling at the extremities. Around half of newborns have a mild case oef the disease that resolves on its own; the other half have severe disease with inflammation of the brain and seizures. In severe cases, affected newborns may also have issues with bleeding and bloodflow, and problems with heart function. In addition to newborns, the elderly, and those with diabetes, heart disease, liver and kidney diseases, and human immunodeficiency virus infection tend to have more severe cases of<unk> . Around 1 to 5 in 1,000 people with symptomatic<unk>  die of the disease.
Chikungunya
Zika fever
Yellow fever
Dengue fever
Trench fever
Rocky Mountain spotted fever
Cuban fever
Blackwater fever