Chikungunya Fever Fact Sheet

Chikungunya Fever Fact Sheet


What is chikungunya fever?
Chikungunya fever is a viral disease transmitted to humans by the bite of infected mosquitoes. Chikungunya virus (CHIKV) is a member of the genus Alphavirus, in the family Togaviridae . CHIKV was first isolated from the blood of a febrile patient in Tanzania in 1953, and has since been identified repeatedly in west, central and southern Africa and many areas of Asia, and has been cited as the cause of numerous human epidemics in those areas since that time. The virus circulates throughout much of Africa, with transmission thought to occur mainly between mosquitoes and monkeys.  

What type of illness does chikungunya virus cause?
CHIKV infection can cause a debilitating illness, most often characterized by fever, headache, fatigue, nausea, vomiting, muscle pain, rash, and joint pain. The term "chikungunya" is thought to be derived from the word "kungunyala" in the Makonde language of southeastern Tanzania and northern Mozambique, which means "to dry up or become contorted".

The incubation period (time from infection to illness) can be 2-12 days, but is usually 3-7 days. "Silent" CHIKV infections (infections without illness) do occur; but how commonly this happens is not yet known.

Acute chikungunya fever typically lasts a few days to a couple of weeks, but as with dengue, West Nile fever, o'nyong-nyong fever and other arboviral fevers, some patients have prolonged fatigue lasting several weeks. Additionally, some patients have reported
incapacitating joint pain, or arthritis which may last for weeks or months. The prolonged joint pain associated with CHIKV is not typical of dengue. Co-circulation of dengue fever in many areas may mean that chikungunya fever cases are sometimes clinically misdiagnosed as dengue infections, therefore the incidence of chikungunya fever could be much higher than what has been previously reported.

No deaths, neuroinvasive cases, or hemorrhagic cases related to CHIKV infection have been conclusively documented in the scientific literature.

CHIKV infection (whether clinical or silent) is thought to confer life-long immunity.

How do humans become infected with chikungunya virus?
CHIKV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on a person infected with CHIKV. Monkeys, and possibly other wild animals, may also serve as reservoirs of the virus. Infected mosquitoes can then spread the virus to other humans when they bite.

Aedes aegypti (the yellow fever mosquito), a household container breeder and aggressive daytime biter which is attracted to humans, is the primary vector of CHIKV to humans. Aedes albopictus (the Asian tiger mosquito)may also play a role in human transmission is Asia, and various forest-dwelling mosquito species in Africa have been found to be infected with the virus.

Where does chikungunya virus occur?
The geographic range of the virus is Africa and Asia.
In Africa, these include Burundi; Central African Republic; Comoros; Democratic Republic of Congo; Guinea; Kenya; Nigeria; Madagascar; Malawi; Mauritius; Mayotte;  Reunion; Senegal; Seychelles, South Africa; Tanzania; Uganda; Zimbabwe.

In Asia, these include Australia; Burma; Cambodia; India; Indonesia; Malaysia; Pakistan; Philippines; Taiwan; Thailand; Timor; Vietnam.

Key Diagnostic Tests

Sudden severe headache, chills, fever, joint and muscle pain are the commonest symptoms.

• Detection of antigens or antibody to the agent in the blood (serology)
• ELISA is available
• An IgM capture ELISA is necessary to distinguish the disease from dengue fever.

Agent Properties and Potential Uses

Chikungunya virus is highly infective and disabling but is not transmissible between people. It would most likely be dispensed as an aerosol or by the release of infected mosquitos. The disabling joint pain and fever, the lack of a suitable animal reservoir in Western countries and its lack of lethality make it a very "clean" weapon that could be used against key civilian installations. The name comes from the Swahili for "that which bends up" that is a reference to the positions that victims take to relieve the joint pain.

 

How is chikungunya virus infection treated?
No vaccine or specific antiviral treatment for chikungunya fever is available. Treatment is symptomatic--rest, fluids, and ibuprofen, naproxen, acetaminophen, or paracetamol may relieve symptoms of fever and aching. Aspirin should be avoided

Infected persons should be protected from further mosquito exposure (staying indoors and/or under a mosquito net during the first few days of illness) so that they can't contribute to the transmission cycle.

What can people do to prevent becoming infected with chikungunya virus?
The best way to avoid CHIKV infection is to prevent mosquito bites. There is no vaccine or preventive drug. Prevention tips are similar to those for dengue or West Nile virus:

• Use insect repellent containing an DEET or another EPA-registered active ingredient  on exposed skin. Always follow the directions on the package.
• Wear long sleeves and pants (ideally treat clothes with permethrin or another repellent).
• Have secure screens on windows and doors to keep mosquitoes out.
• Get rid of mosquito breeding sites by emptying standing water from flower pots, buckets and barrels. Change the water in pet dishes and replace the water in bird baths weekly. Drill holes in tire swings so water drains out. Keep children's wading pools empty and on their sides when they aren't being used.
• Additionally, a person with chikungunya fever or dengue should limit their exposure to mosquito bites in order to avoid further spreading the infection. The person should stay indoors or under a mosquito net.

Dr Marwah

Chikungunya Outbreak of 2004-Present

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An analysis of the virus's genetic code suggests that the increased severity of the 2005-present outbreak may be due to a change in the genetic sequence, altering the virus' coat protein, which potentially allows it to multiply more easily in mosquito cells. ^[1] In July 2006, a team analyzed the virus' RNA and determined the genetic changes that have occurred in various strains of the virus and identified those genetic sequences which led to the increased virulence of recent strains. ^[2]

2005

In February 2005, an outbreak was recorded on the French island of Réunion in the Indian Ocean. As of May 18, 2006, 258,000 residents have been hit by the virus in the past year (out of a population of about 777,000). 219 official deaths have been associated with Chikungunya. ^[3]

In neighboring Mauritius, 3,500 islanders have been hit in 2005. ^[4] There have also been cases in Madagascar, the Comoros, Mayotte and the Seychelles.

In Nandurbar city of Maharashtra State (India), many people over age 60 died due to chikungunya induced complications. Three months after the viral infection, patients were still suffering from severe joint pain in the morning, dyspepsia, relapsing fever, swelling in the joints. Doctors should also be alert for platelet count abnormalities suggestive of Dengue or Falci. Malaria. ( Dr.Manoj Tamboli)

2006

In 2006, there was a big outbreak in the Andhra Pradesh state in India. The initial cases were reported from Hyderabad and Secunderabad as well as from Anantpur district as early as November and December 2005 and is continue unabated. In Hyderabad alone an average practitioner sees anywhere between 10 to 20 cases every day. Some deaths have been reported but it was thought to be due mainly to the inappropriate use of antibiotics and anti inflammatory tablets. The major cause of morbidity is due to severe dehydration, electrolyte imbalance and loss of glycemic control. Recovery is the rule except for about 3 to 5% incidence of prolonged arthritis. As this virus can cause thrombocytopenia, injudicious use of these drugs can cause erosions in the gastric epithelium leading to exsanguinating upper GI bleed (due to thrombocytopenia). Also the use of steroids for the control of joint pains and inflammation is dangerous and completely unwarranted. On average there are around 5,300 cases being treated everyday. This figure is only from public sector. The figures from the private sector combined would be much higher.

There have been reports of large scale outbreak of this virus in Southern India. At least 80,000 people in Gulbarga, Tumkur, Bidar, Raichur, Bellary, Chitradurga, Davanagere, Kolar and Bijapur districts in Karnataka state are known to have been affected since December 2005. ^[5]

A separate outbreak of Chikungunya fever was reported from Malegaon town in Nasik district, Maharashtra state, in the first two weeks of March 2006, resulting in over 2000 cases. In Orissa state, at most 5000 cases of fever with muscle aches and headache were reported between February 27 and March 5, 2006. ^[6]

In Bangalore, the state capital of Karnataka (India), there seems to be an outbreak of Chikungunya now (May 2006) with arthralgia/arthritis and rashes. So also in the neighbouring state of Andhra Pradesh. In the 3rd week of May 2006 the outbreak of Chikungunya in North Karnataka was severe. All the North Karnataka districts specially Gulbarga, Koppal, Bellary, Gadag, Dharwad were affected. The people of this region are hence requested to be alert. Stagnation of water which provides fertile breeding grounds for the vector (Aedes aegypti) should be avoided. The latest outbreak is in Tamil Nadu, India - 20,000 cases have been reported in June 2006. Earlier it was found spreading mostly in the outskirts of Bangalore, but now it has started spreading in the city also (Updated 30/06/2006). More that 300,000 people are affected in Karnataka as of July 2006. ^[7]

Reported on 29/06/2006, Chennai - fresh cases of this disease has been reported in local hospitals. A heavy effect has been reflected in south TN districts like Kanyakumari and Tirunelveli. Residents of Chennai are warned against the painful disease.

June 2006 - Andaman_Islands (India) Chikungunya cases had been registered virtually for the first time in the month of June 2006. In the beginning of the September cases have gone as much as in thousands.As reported in a local news magazine it has taken the state of epidemic in Andamans. Health authorities are doing their best to handle the situation.Relapsed cases have been noticed with severe pain and swelling in the lower limbs, vomiting and general weakness.

As of July 2006, nearly 50,000 people were affected in Salem, Tamil Nadu. ^[8]

As of August 2006, nearly 100,000 people were infected in Tamil Nadu. Chennai, capital of Tamil Nadu is one of the worst affected.

On 24 August 2006, The Hindu newspaper reported that the Indian states of Tamil Nadu, Karnataka, Andhra Pradesh, Maharashtra, Madhya Pradesh, Gujarat and Kerala had reported 1.1 million (11 lakh) cases. The government's claim of no deaths is questioned. ^[9]

As of 31 August 2006, neighbouring cities of Salem, Erode and Coimbatore have been severely affected by this epidermic. All the above places are in South India

11 September 2006 - an outbreak is under way in the western parts of India, specifically the southeast parts of the state of Gujarat, which are recovering from the heavy rainfall caused floods. Chicken gunya is also noticed in some parts of Goa, specially the south Goa. About 5,000 people have already been suffering from chicken gunya.

19 September 2006 - after the flood and heavy rains in Rajasthan in August 2006, India, thousands cases been detected in Rajasamand, Bhilwara, Udaipur, Chittorgarh district. However surprisingly there is no mention of all these in media or by Government.

21 September 2006 - Delhi-based family members got infected as well.

22 September 2006 - case detected back home in the United Kingdom traveller based in Udaipur at the time of floods in August/September. Symptoms included rash, fever, muscle and joint pain, severe headache. Antihistamines prescribed for itching. Advised six weeks of fatigue to follow after five days of acute illness. Recommended rest and plenty of fluids.

2 October 2006 - Total of 61 deaths has been reported in the state of Kerala, India. 30,000 people are reported to have admitted in hospitals run by govt. agencies, the number from private clinics are unknown. ^[10]

15 October 2006 - Chikungunya cases have been reported in the town of Etawah in Uttar Pradesh, India.

16 October 2006 - Many confirmed cases in Kanpur, UP (Uttar Pradesh). Etawah confirmed above. It is slowly spreading towards Northern India perhaps.

June 2007   Kerala State has been overtaken by yet another calamity in the form of chikungunya epidemic that has taken over a hundred lives. The state government of Kerala is treating this as a statewide emergency.

--
Dr Marwah

Reducing Pain of Pediatric Immunizations

• The pain associated with immunizations can create anxiety and distress for the children receiving the immunizations, their parents, and healthcare providers. Dread evoked by painful immunization procedures may create feelings of persistent tension in future clinical encounters, thereby interfering with optimal delivery of healthcare.
• The injection process can be divided into 2 periods: before the injection and during the injection.
• Before the injection, preparation of a child older than 2 years reduces anxiety and subsequent pain. Children younger than 4 years should be prepared shortly before the injection itself.
• Intramuscular immunizations should be administered in the vastus lateralis (anterolateral thigh) for infants and toddlers younger than 18 months and in the deltoid (upper arm) for children older than 36 months. The ventrogluteal area may be the most appropriate site for all age groups.
• Despite the common belief that the shortest needle with the thinnest gauge would produce the least trauma and pain, this does not seem to be the case. Several studies suggest that longer needles, which are more likely to penetrate muscle than shorter ones, cause less pain, fewer adverse effects, and less local reaction.
• During the injection, parental attitudes affect the child's pain behaviors. Excessive parental reassurance, criticism, or apology tends to increase distress, whereas humor and distraction may reduce distress.
• The child's age, temperament, and interests and parent's personal style will aid in selecting effective distraction techniques. These may include storytelling, reading to the child, deep breathing, and blowing.
• During injection to children younger than 6 months, sucrose solution should be routinely given directly into the mouth or on a pacifier. This decreases evidence of distress and is relatively inexpensive.
• Because of the high cost and time needed for administration, routine local anesthetic administration is not indicated, but selective use is recommended for children who are especially fearful, who have had previous negative experiences, or who will require multiple procedures in the future.
• Pressure at the immunization site decreases pain, whether applied with a device or finger, and this strategy is noninvasive, inexpensive, and without adverse effects. Properties of the injectate itself can exacerbate pain, but there has been little research in this area.
• Parents often prefer that multiple injections be given simultaneously, rather than sequentially, if there are sufficient personnel.

--
Dr Marwah