Chikungunya, a common viral disease from Africa and Asia, now in the Americas. Chikungunya virus infection, its causes, symptoms, treatment.
This infection used to be a frequent disease only in Africa, India, and Southeast Asia. However, in 2013, the first cases of Chikungunya transmission in America appeared. Mainly in the Caribbean and tropical countries, but traveling activities have risen the cases in the USA. The latter country has around 28 cases every year. These cases were from travelers returning from foreign territories, although local transmissions (in people who did not travel) in Florida occurred in one year with eleven cases.
In Europe, the disease arrived in 2007 when around 200 cases happened in Italy. This raised alerts in other European countries about the possibility of transmission in the continent. Some European dependencies in the Americas, like Saint Martin, British Virgin Islands, and Guadeloupe, have reported transmission in their territories.
Learn more about this disease directly from a doctor in the lines below.
What is Chikungunya? Where does the name come from?
Chikungunya is a viral infection. The virus that causes the disease is the Chikungunya virus (CHIKV). The disease is also called Chikungunya fever (CHIKF). It is transmitted through the bite of an infected Aedes mosquito. This is the family of mosquitoes that can transmit other diseases like Zika, Dengue fever, or yellow fever. This means that Chikungunya is a mosquito-borne disease.
Chikungunya infection is a self-limiting disease. This means that symptoms will usually go away without treatment. Therefore, there is no specific treatment to cure it. The main and most common symptoms are fever and joint pain. Other symptoms can appear but may vary from one person to another and will be reviewed further in the article.
The name comes from an African language. It translates as “to be bent over.” This meaning refers to the position patients with Chikungunya take because of the severe joint pain.
How is it transmitted? Is it contagious from human to human?
Virus transmission depends on a mosquito vector. This means that the mosquito has to bite a sick patient in the first week to pass on the disease. And it only passes the disease about ten days after biting the ill person. CHIKV is not contagious from one person to another. However, sick people during epidemics should rest under a net during the day to prevent mosquito bites.
The main mosquitoes in charge of transmitting the virus are Aedes aegypti and Aedes albopictus. They are responsible for transmission in urban areas where they bite infected humans and pass the disease to other people. Other types of Aedes mosquitoes are present in rural areas. These mosquitoes commonly pass the infection from some animals that can be carriers of the virus.
Mosquitoes lay their eggs in fresh, stored water. For this reason, it is essential to eliminate water where these insects reproduce. People should avoid storing water in open containers. They should continuously renew the water in flower vases. Garbage like tires or tins that can store rainwater outside must be cleared. If the mosquito cannot reproduce, fewer mosquitoes can infect people. These recommendations are essential year-long, but they are vital for disease control during a Chikungunya outbreak. Outbreaks occur when more people than expected start getting a specific disease.
For travelers to zones where Chikungunya is frequent, the main goals are to prevent mosquito bite. Wearing long clothes and using repellents is usually enough. Another possible measure is to limit outdoor activities, as the mosquito is more likely to bite outdoors.
What are the symptoms of Chikungunya?
The disease appears with a mean of 3-7 days after the mosquito bite but can go anywhere from 1 to 12 days. The first symptom is a high fever (39-40 °C/102-105 °F) that lasts approximately 3-4 days. It can reappear after one day without fever.
Severe joint pain is also frequent. It occurs in two phases. The first or acute phase is generalized polyarthralgia, which means that it affects many joints. Patients refer that pain is not always in the same spots, which is called “migratory arthralgia.” Ankles, wrists, and small joints of the hands and feet are commonly affected. However, large joints like the shoulder, the knee, or the spine can also be involved.
Up to ten joints can be affected at the same time. Joint swelling, tenderness, pain, and stiffness are worse in the morning, getting slightly better with mild activity. These joint pain characteristics are similar to the ones of rheumatoid arthritis (RA), an autoimmune disease that affects joints.
Nevertheless, RA appears more progressively and has no relation to visits abroad. The acute phase in chikungunya is incapacitating and tends to last less than two weeks. Still, it can last up to one month. And sadly, roughly 1 in 10 patients experience joint pain for months.
Another common manifestation of Chikungunya virus disease is a skin rash. It appears in 2-5 days after the fever has started. The rash is usually red, with small spots and lumps (maculopapular rash), and is itchy. It can appear in the chest or the entire body. Rashes and skin manifestations can vary from one person to another. Some children can present rashes with small blisters in the whole body, but it is not very common.
In some cases, patients have small red or purple spots on the skin called petechiae. They are very similar to the ones caused by the dengue virus. Other symptoms may be present but are not as frequent.
What other symptoms are there in Chikungunya?
It is very likely to experience other symptoms besides fever and joint pain. Most of them are very unspecific. Some include headache, face swelling, muscle pain, nausea or vomiting, pink eye, light eye sensitivity, and pain behind the eyes.
In the skin, besides the maculopapular rash, some areas’ skin color changes are also common. Also, a small number of patients can have ulcers (skin wounds) in skin folds.
A varying number of patients have neurologic symptoms. This means that the virus can affect the brain and nerves. The main neurologic symptom is dizziness or sleepiness, but seizures and abnormal sensations are possible.
What are the complications of Chikungunya fever? Is it mortal?
The most important complication is long-lasting joint pain. It is more severe in patients with previous rheumatologic conditions like rheumatoid arthritis. Even in patients without other diseases, chronic joint pain is disabling. It can cause both physical and mental consequences.
Eye complications include inflammation of some specific parts of the eye. These complications are iridocyclitis, retinitis, uveitis, or nodular scleritis. Patients can experience impaired vision, but it usually has a good recovery rate.
Severe disease cases can present with Guillain-Barré syndrome. This is when the nerves start paralyzing, from the toes, progressing towards the upper body. It becomes life-threatening when it paralyzes the nerves that control the breathing.
Despite this, Chikungunya is an illness with a low mortality rate. The risk of life-threatening complications is relatively low. Those at risk are older people and patients with conditions such as diabetes or high blood pressure.
What tests are needed to diagnose Chikungunya fever?
Different types of tests are available to diagnose Chikungunya infection. The most common is serologic testing. In this procedure, the laboratory will test the blood sample for the presence of anti-Chikungunya antibodies. Antibodies are proteins in the blood that help fight off infections. If specific antibodies against Chikungunya are present, the diagnosis is certain.
However, it is not that simple. Antibodies develop at the end of the first week of the illness. Two types of antibodies appear in the blood: IgM and IgG. A blood sample from an acute phase patient goes through testing for both types. Multiple scenarios are possible. In some cases, patients need a second test 14 days apart. A doctor should help with the interpretation of results.
Other tests (like the polymerase chain reaction technique) can directly confirm the virus’s presence in the blood sample. Nevertheless, these are not widely available and are very expensive.
What is the treatment?
Since the disease is self-limiting, it has no specific treatment. During the first phase, where the fever is active, it is vital to rest under a mosquito net. This way, no mosquito will bite the patient, with the risk of infecting someone else.
The only recommended medication is acetaminophen since it should help relieve the fever and joint pain. After ruling out other diseases such as Dengue, doctors may indicate other medications. These include Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) like ibuprofen or naproxen. Never take new medications without a doctor’s advice.
There is no general agreement on whether corticosteroids are beneficial or not. Doctors evaluate each case to decide if it may improve the patient’s condition.
Patients with long-lasting joint pain have reported benefit from physical therapy. Regulated, mild movements improve pain and joint stiffness, while intense exercise can worsen symptoms.
Can a person get Chikungunya twice? Is there a vaccine?
After getting Chikungunya for the first time, the body produces antibodies. The same proteins that help the doctor make the diagnosis. These antibodies can detect the virus if it tries to infect a person a second time. The body destroys the virus, and the disease does not happen. Up to date, there are no reports of a Chikungunya second infection (reinfection). Disease recovery for the first time provides life-long immunity.
Vaccines teach your immune system how to detect the virus without getting the disease for the first time. Some vaccines to prevent Chikungunya are under development, but they are not available to the public yet.
What is the difference between Dengue and Chikungunya?
Both diseases are viral infections, and they even have the same vector or transmission mode. This means that both diseases are common in the same areas, making them a bit difficult to tell apart. There even are cases of infections of both viruses in the same patient at the same time. Dengue complications are more likely to be fatal. Therefore, differentiating between both diseases is very important in order to deliver the proper care.
The main clinical differences are:
- Fever usually appears more acutely in CHIK. It usually is around 40 °C the first day and lasts a maximum of 4 days. In Dengue, fever gradually rises and lasts about a week.
- A maculopapular rash is more common in Chikungunya, but it can also happen in Dengue.
- Joint pain is very severe and long-lasting in Chikungunya, while it is less intense in Dengue.
- Joint inflammation (swelling, redness, heat) is a classic manifestation of Chikungunya. It really is not present in Dengue fever.
- Chikungunya rarely has bleeding manifestations. On the other hand, they are a more common symptom of Dengue.
- Shock, a dengue complication, is extremely rare in Chikungunya infection.
- In some cases, blood parameters may also help differentiate between Dengue and Chikungunya. A full blood count test measures the amounts of different blood components. Platelets are commonly low in Dengue, while they rarely have alterations in Chikungunya. Other alterations involving the white blood cells are possible in both diseases. A doctor’s judgment is better in these cases.
Do you have symptoms of this disease?
This tool is a Chikungunya Symptoms Checker. It gathers the most important signs, symptoms, and risk factors for the infection. Therefore, the tool will tell anybody who uses it the likelihood of their symptoms because of Chikungunya. Using the tool is free and would only take a few minutes.