Chikungunya Arthritis

Chikungunya ArthritisChikungunya arthritis is endemic in Maharashtra and other states of India since 2006. It is caused by Chikungunya virus. Just as virus causes sneezing cold due to swelling inside nose, Chikungunya virus causes joint pain due to swelling inside joints. Chikungunya virus was initially isolated in 1953 at Makonde plateau (Tanzania) along border of Tanzania and Mozambique. The word Chikungunya implies ‘a disease which bends up’ in Makonde language. Chikungunya virus spreads via Aedes aegypti mosquitoes which breed on clear water and bite during daytime. This mosquito bites many people for a single meal, thus infecting many people in a short time. These mosquitoes also spread diseases such as dengue, yellow fever (jaundice) and filariasis.

Fever, crippling joint pains and stiffness all over body are the main features. Joints of hands and feet including wrists and ankles are commonly involved. The pain improves with activity but worsens after strenuous exertion. Pain lasts for a week or so in most patients. Joint pains may require months to resolve completely. The arthritis may persist and become chronic in about 12% cases. Prolonged joint pain is particularly troublesome in elderly patients and in those with other forms of arthritis, heart disease or hemiplegia. Minor itchy skin rashes may appear but are less evident in Indian patients. Headache, redness of eyes, muscle pains, back pain, soar throat and severe fatigue may occur in some patients. Some cases can develop complications in form of involvement of kidneys and nervous system. A few deaths have also been reported.
No tests are required in a typical case occurring in an endemic area. Special blood tests can show IgM antibodies for more than6 months. Rheumatoid factor may be positive in low titers. Many other viruses such as hepatitis, HIV, mumps and Rubella also cause arthritis.
Late Phase
Late phase of Chikungunya is an immune mediated reaction triggered by the virus and is characterized by persistent joint pains and arthritis in over 74% cases. Skin lesions, headache, insomnia and fatigue persist in 3-7% cases. Patients with severe and prolonged (>30 days) initial joint symptoms require more time to recover. Rheumatic symptoms are mild in most cases and can be fluctuating or constant. Chronic arthritis involves more than 4 joints in 76% cases. It usually affects ankles, knees, wrists and small joints of toes and fingers.  Female sex, obesity, Chik V IgG positivity, lower education level and presence of osteoarthritis are risk factors for chronic sequelae. Rest during acute phase does not prevent development of late complications. Severe and unusual forms of arthralgias have been observed following recent epidemic. Tendonitis, bursitis and enthesitis can also occur. These features persist for more than 30 days and lead to catastrophic health expenditure (lost work days and out of pocket expenses). Some studies indicate persistence of arthritis for 15-20 months to 3-5 years. Erosive arthritis and triggering of rheumatoid arthritis have also been reported. In fact, a symmetric polyarthritis of more than 6 week duration can be easily mistaken for rheumatoid arthritis.
Adequate rest, ample fluids, light exercise and painkillers are advised in all cases of acute arthritis. Steroids in small doses offer better pain control. Chronic Chikungunya arthritis requires expert care with various disease modifying drugs. One attack of Chikungunya infection confers lifetime immunity against the virus. Treatment of late phase is similar to that of rheumatoid arthritis although drugs may be required in lower doses and for shorter duration.
Measures to prevent mosquito-bites by wearing full pants and full sleeves and use of mosquito repellents even during day-time are important. Instructions from local authorities must be strictly followed. Observance of a dry day once a week is helpful. Water-holding containers such as tins, cans, empty pots, flower vases, discarded rubber tyres, broken bottles, coconut shells and similar other items must be destroyed or cleaned and dried up. Control of larvae and adult mosquitoes by cleaning environment and use of appropriate insecticides is also essential.