The rainy season due to the South West Monsoon over the Indian sub continent is over.Epidemic of acute severe joint pain and swellings associated with fever due to Chikungunya infection has also subsided.Now I am seeing more and more patients with Chronic severe joint pain of varying duration, a sequel of Chikungunya infection.
Let me tell you a little more about this virus and the illness it causes in humans.
Chikungunya is a re-emerging, mosquito-borne viral infection causing fever, rash and acute or sudden severe joint pains of several joints.Chikungunya (Chick’-en-GUN-yah) in Swahili an African language meaning “that which contorts or bends up” refers to the contorted (stooped) posture of patients who are afflicted with severe joint pains (arthralgia) the most common feature of the disease.
Chikungunya virus is a single-stranded RNA Alphavirus, from the family Togaviridae. Other Alphaviruses also causing fever, rash and arthralgia, include O’nyong-nyong, Mayaro,Barmah Forest, Ross River and Sindbis viruses. Chikungunya virus is most closely related to O’nyong-nyong, but remains genetically distinct.
The disease was first described by Marion Robinson and W.H.R. Lumsden, following an outbreak along the border between Tanzania(erstwhile Tanganyika) and Mozambique, in1952. Since 1953, the virus has caused outbreaks in Africa and South Eastern Asia, including India, Sri Lanka, Myanmar, Thailand, Indonesia, the Philippines and Malaysia, which are well documented. There is historical evidence that Chikungunya virus originated in Africa and subsequently spread to Asia. Phylogenetic studies support this theory, with Chikungunya virus strains falling into three distinct genotypes based on origin from West Africa, Central/East Africa or Asia.
Chikungunya is transmitted by the bite of the infected Aedes mosquito from an infected person to a healthy person. The disease does not get transmitted directly from human to human (i.e. it is not a contagious disease). In a pregnant woman with Chikungunya there is risk of transmitting the disease to her foetus.
The fever starts usually about 2 to 3 days after the entry of virus into the human body. There will be severe chills and shaking of the body at the onset of fever.At the same time the joint pain and swelling starts.The patient will not be able to move with in minutes of onset of illness.The joints of hands mainly the metacarpo phalangeal and proximal inter phalangeal joints become warm swollen and very painful.Wrist and elbow are also affected to a lesser extend.The joints of ankle,feet and to a lesser extend hip are all affected.
Itchy reddish raised rash is typically seen[70%] when the fever subsides, which in most of my patients was by 3 days.Many patients and Physicians confuse it with drug rash due to allergy to the medicines the patient took for fever and joint pain.
Rash is typically seen on the cheeks, nose and outer part of ears.The ear lobe is typically painful to touch. The rash is also seen over the trunk and limbs with severe itching which lasts for only 2 days. There will be painful swelling of ankle and shin with dark red discoloration. Painful oral ulcers are also seen during this time.Last year I had few patients with enlarged cervical lymph nodes, which disappeared in few days.
Although rare, the infection can result in meningo-encephalitis, especially in newborns and those with pre-existing medical conditions. Pregnant women can pass the infection to their foetus. Severe cases of Chikungunya can occur in the elderly, in very young ones (newborns) and in those who are immuno-compromised.
Chikungunya outbreaks typically result in several hundreds or thousands of cases but deaths are rarely encountered.
Differential diagnosis of Chikungunya includes Dengue and Dengue Haemorrhagic Fever,
O’nyong-nyong virus infection and Sindbis virus infection.
It has been reported that attack rates in susceptible populations may be as high as 40-85 per cent and the ratio of symptomatic to asymptomatic patients is about 1.2:1.
Children are less likely to experience joint pain, but may have other features such as febrile fits, vomiting, abdominal pain and constipation.
The discoloration of the nose usually lasts for months.I call it the seal of Chikugunya as I can identify a person who had Chikungunya in the recent past seeing that seal.
Some patients may remain feverish for some more days. The joint pain become less in few days. In about 60 percent of the patients the ilness including the joint pains last only about a week.They become completly all right with only a little bit of tiredness remaining.
But in about 40% of patients joint pain increases or persists.The chronic joint pain of Chikungunya resembles that of Rheumatoid arthritis. The joints commonly involved are the wrists and the knees.The ankle and smaller joints of feet and hands are also involved.Stiffness of these joints in the morning lasting more than 30 mts is typical. The patient feels better as he/she continues to move the joints.
The joint stiffness and pain lasts for about 3 months in about 30% of patients in my practise. But in an unfortunate 10% it may last indefinitely.
Lab Diagnosis of Chikungunya fever
Virus isolation and PCR techniques are costly and is available in very few centres. Serological diagnosis is possible only after a week of onset by detecting antibodies. As the treatment is mostly symptom specefic diagnosis will not alter patient management much. So the typical triad of fever, acute onset joint pains and rash along with a low white cell count in blood sample is sufficient enough to diagnose Chikungunya fever
Treatment of Chikungunya fever
Paracetamol 10 to 15mg per kg body weight given 3 to 4 times a day reduces the fever.It is needed only in the first 2 to 3 days of illness.
Non Steroidal anti inflammatory agents have to be given liberally to reduce the pain and swelling. This may have to be continued for few weeks in some patients with persistent joint pain. Renal and Gastric safety have to ensured while taking such medicines.
Short course of steroids like Prednisolone also helps in resistant cases.
Other analgesics like Tramadol are also useful.
Disease modifying anti rheumatic agents like Chloroquine have been found useful in some studies.Personally I feel Chloroquine is not of much help as it is a slow acting drug taking almost 3 months to be fully effective.
Most of the patients who turned to alternative systems of medicine for relief came back to me saying there is no relief to pain.Many had to take NSAIDs along with their Ayurvedic and Homeopathic medicines which proved that other systems have nothing much to offer.
In short Chikungunya fever is easy to diagnose but not that easy to treat, but to those who suffer it is pure hell.