Chikungunya
Chikungunya is caused due to a viral infection (CHIKV) and is transmitted when an infected female Aedes aegypti mosquito carries the virus from an infected human to a healthy person. The mosquitoes mostly attack during the day and are commonly seen breeding around clean water bodies. Chikungunya means ‘to distort’, directly relating to the stooped appearance of the patient due to extreme pain in and around the joints during the disease. The disease is characterised by an abrupt onset of fever frequently accompanied by severe muscle and joint pains. Once bitten, the patient will experience symptoms such as arthritis like pain around the joints, muscle aches, fever, malaise, headache, fatigue, nausea and in some cases vomiting within approximately two to 22 days.
Chikungunya is a self-resolving disease. It gradually decreases in intensity in about a week after infection. But some people may experience arthritic pain and fatigue for a few weeks to a year after it has resolved. In very old and ailing patients and in individuals with a weak immune system, the disease can result in death.
Blood tests can help diagnosis. Doctors can now quickly and accurately identify patients at risk of severe form of chikungunya with the help of a direct biomarker. There is currently no cure for the condition. Medications are given for symptomatic relief from pain, swelling and fever.
Causes
Dr Amitabh Parti, additional director, internal medicine, Fortis Memorial Research Institute, Delhi says, 'Chikungunya is caused due to a viral infection (CHIKV) and is transmitted when an infected mosquito carries the virus from an infected human to a healthy person. They are commonly seen breeding around clean water bodies and mostly attack during the day'.
Usually confused with dengue and in some cases malaria, chikungunya is a self resolving disease (the condition gradually decreases in intensity in about a week after infection) that does not have a cure. As an exception, some people experience arthritic pain and fatigue for a few weeks to a year after it has resolved.
The reason why this vector-borne virus reappeared is due to the virus mutation and lack of proper sanitation, which promotes breeding of the mosquitoes. Also, inadequate fogging and anti-larvae measures increase the risk of the infection. It has also been proposed that another strain of the Aedes mosquito might be responsible for carrying the virus.
Symptoms
A condition that is spread by the female Aedes aegypti mosquito, ‘chikungunya’ means ‘to distort’, directly relating to the extreme pain the patient experiences in and around his/her joints during the disease. Once bitten the patient will experience symptoms such as
- Arthritis-like pain around the joints
- Muscle aches
- Fever
- Malaise
- Headache
- Fatigue
- Nausea
- Vomiting (within approximately two to 22 days of infection, in some cases)
- Tender lymph nodes
- Swelling behind the ears and in neck
Here are how the symptoms of chikungunya are different from malaria and dengue.
There are very subtle differences between the three mosquito borne diseases and one of the most clear difference is the type and frequency of fever a patient experiences.
In the case of dengue a patient suffers from high fever that appears and subsides quickly only to reappear with rashes and in the case of dengue haemorrhagic fever, along with bleeding.
In malaria, the patient suffers from high fever, most predominantly in the evenings with chills followed by sweating in quick succession.
In the case of chikungunya, the patient suffers a high fever with severe pain in the body especially the joints along with all the symptoms mentioned above. In all three conditions, the patient will experience a temperature of about 102o .
Diagnosis
Most doctors do tend to diagnose the condition using a process of elimination – by testing for dengue and malaria first then followed by tests for chikungunya.
The diagnostic test for the condition is a simple blood test where the sample is tested serologically using the ELISA test (Enzyme-linked immunosorbent assays) or PCR (polymerase chain reaction) to check for the presence of the anti-chikungunya antibody in the patient’s blood.
If the patient is infected, the amount of immunoglobulin is the highest in the first two weeks after the onset of symptoms and continues to be present in the body for about two months after that.
Treatment
The treatment for chikungunya is self-limiting and managed conservatively. Doctors prescribe medication to give symptomatic relief to the patient. Drugs to reduce the pain, swelling and fever that appear with the disease are usually the first line of treatment. That being said there have been a number of research studies to identify a possible vaccine and treatment for the condition.
A study published in the American Journal of Tropical Medicine and Hygiene in 2000 said that they had developed a vaccine that showed 98% efficacy in its patients. This vaccine is still not available in the market. Other studies on a possible DNA vaccine for the chikungunya vaccine is still underway.
Although this condition has no known complications it can cause death in very old and ailing patients.
If you do think you might have the condition it is extremely important to get diagnosed early, since the symptoms overlap with conditions that have serious complications like dengue and malaria.
Prevention
Here is what you should do to prevent from getting infected with the disease:
Since infected mosquitoes, bite during the day, it is advisable to use a mosquito repellent cream while stepping out, especially in endemic areas.
- Use repellants within the house and use them as per the recommendations on the packaging.
- Keep all water reservoirs like buckets, small tubs, mugs etc. covered at all times. It is essential to empty out all the containers regularly and wash them well.
- Declutter your home and air our all the rooms once a day. Remember to close all your windows and doors by mid morning.
- If you have too many mosquitos in your area, ask your area municipal corporation to get the area sprayed to rid it of mosquitoes.
Finally, what you need to remember is that if you experience symptoms like fever, joint pain, malaise, fatigue and vomiting make sure you visit a doctor at the earliest. Do not self-medicate because it could be something more serious.
The content has been verified by Dr Amitabh Parti, additional director, internal medicine, Fortis Memorial Research Institute, Delhi.
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