|Classification and external resources|
Rash from chikungunya on the right foot
Chikungunya (pronounced "chicken-GUN-yay") is an infection caused by the chikungunya virus. It can cause joint pains that can last for weeks, months, or sometimes even years. About 1 in every 1000 people who gets chikungunya dies. People who are elderly or have other medical problems are most likely to die or get very sick from chikungunya.
Chikungunya is spread to humans by two species of mosquito: Aedes albopictus and Aedes aegypti. These mosquitoes carry the infection to humans after biting monkeys, birds, cattle, or rodents who have chikungunya. Since 2004, there have been outbreaks (where many people get chikungunya) in Asia, Europe, and The Americas.
Signs and symptoms[change | change source]
It can take one to twelve days for a person to get sick after they get the chikungunya virus. (This period of time is called the virus's incubation period.) Usually, people get sick in three to seven days. Most people who get the virus (72% to 97%) get symptoms.
Acute phase[change | change source]
The acute phase usually begins with a sudden high fever that can last up to ten days. The fever is usually above 39 °C (102 °F), and can sometimes get as high as 40 °C (104 °F). About half of people with chikungunya get a rash, usually about two to five days after symptoms start. Some people also have gastrointestinal symptoms, like abdominal pain, nausea, vomiting, or diarrhea. In rare cases, people may get conjunctivitis or other problems with their eyes.
The body starts to fight the virus after about a week by sending out immunoglobulin M (IgM), which attacks the virus. After this, most of the symptoms usually start to get better. However, people often keep having some symptoms for about another week, like headache, insomnia (trouble sleeping), and exhaustion. After these symptoms end, the acute phase of chikungunya is usually over.
Chronic phase[change | change source]
In chikungunya's chronic phase, almost everyone with the virus (87% - 98%) gets very bad joint pain or stiffness. This usually lasts for weeks or months. However, it can last for years. The joint pain can be so bad that a person cannot move the joints that hurt. The pain almost always happens in more than one joint. Usually, people have pain in the joints in their arms and legs, on both sides. These may include the joints in the wrists, ankles, hands, feet, shoulders, elbows, and knees. The virus can also cause pain in the muscles or ligaments.
Sometimes, it can be difficult to tell the difference between chikungunya and dengue fever. Both infections cause some of the same symptoms, like fever and very bad pain. However, chikungunya usually does not cause bleeding. If a person diagnosed with chikungunya has bleeding problems, they may:
- Have dengue fever instead of chikungunya
- Have both chikungunya and dengue fever (both are spread by mosquitoes, and are common in some of the same places)
- Have both chikungunya and liver problems
Prevention[change | change source]
The best way for people to protect themselves from chikungunya is to protect themselves from mosquitoes in places where the disease is common. For example, people may use bug spray and mosquito nets, and wear long sleeves and long pants when they are outside. In places where chikungunya is common, governments can also do things to control the number of mosquitoes. For example, they can spray pesticides.
There is no vaccine for chikungunya. Scientists are doing experiments to try to make a vaccine. However, scientists say that even if they created a vaccine, people would still have to control mosquitoes to prevent chikungunya.
Treatment[change | change source]
Medical professionals can only give "supportive care." This means they can only treat chikungunya's symptoms. For example, they may treat fever and joint pain with nonsteroidal anti-inflammatory drugs (NSAIDs) like naproxen; painkillers like paracetamol (acetaminophen); and fluids. Aspirin is not given because it can make bleeding more likely to happen.
Chronic joint pain[change | change source]
Scientists have not found any medication that helps everyone with chikungunya who has bad joint pain. There is some evidence that certain medicines may help people who have bad joint pain for more than two weeks. These medicines include:
- Ribavirin, an anti-viral medicine
- Chloroquine, a medicine usually given to prevent malaria
- Methotrexate, a medicine used for rheumatoid arthritis, which also causes very bad joint pain
About 1 in 1000 people who get chikungunya die from the disease. People older than 65, newborn babies, and people with other medical problems are most likely to have the most dangerous problems. Chikungunya is especially dangerous for newborns because they can get the virus from their mothers during childbirth, and because newborns' immune systems have to grow before they work as well as adults'. This makes it much more difficult for newborns to fight off the virus.
In the past, chikungunya existed mostly in developing countries. However, more recently, there have been epidemics (where a very large number of people get the virus) in the Indian Ocean, the Pacific Islands, and the Americas.
When chikungunya was first discovered in 1952, it was uncommon and happened only in West Africa. People usually got the disease during rainy seasons, because mosquitoes are more common during these times. Beginning in the 1960s, there were sometimes outbreaks in Asia and Africa. However, until 2005, chikungunya had been uncommon throughout the world.
Since 2005, chikungunya has become much more common. It has caused large outbreaks in Africa, Asia, and the Americas. For example, in India, chikungunya re-appeared after 32 years where no Indian person had gotten the virus. Outbreaks have also happened in Europe, the Caribbean, and South America, where chikungunya had never spread before. A few people have also gotten chikungunya in the United States and Australia, where the virus had never lived before.
In 2005, there was a very large outbreak on Réunion, an island in the Indian Ocean. Out of about 770,000 people who lived on the island, about 266,000 (over 1 in every 3 people) got chikungunya. In 2006, about 1.25 million people in India got the virus.
Chikungunya was recently spread to the Americas. From 2013-2014 in the Americas, 1,118,763 people have been thought to have the virus. Of these cases, 24,682 were proven to be chikungunya.
Some scientists think that chikungunya has become much more common because of a change in the virus's genetic code. This change may have made it easier for the virus to make copies of itself in mosquito cells. It may have also allowed the virus to be spread more easily by the Asian tiger mosquito (Aedes albopictus). This is important because the Asian tiger mosquito lives in many more places than Aedes aegypti, the other species of mosquito that spreads chikungunya to humans. Aedes aegypti lives only in tropical places. However, the Asian tiger mosquito spreads easily, and lives in Europe, the Americas, the Caribbean, Africa, and the Middle East.
History[change | change source]
Chikungunya was first described by Marion Robinson and W.H.R. Lumsden in 1955, after an outbreak in 1952 along the border between Mozambique and Tanganyika (now part of Tanzania). A group called the Makonde lived in this area. The word "chikungunya" probably comes from the Makonde language. It means "that which bends up" or "to walk bent over." This describes how people with very bad joint pain from the virus would bend into unusual positions.
References[change | change source]
- "Chikungunya". Oxford Learner's Dictionary. Oxford University Press. http://www.oxfordlearnersdictionaries.com/us/definition/english/chikungunya. Retrieved 4 November 2014.
- Powers AM and Logue CH 2007. "Changing patterns of chikungunya virus: re-emergence of a zoonotic arbovirus". Journal of General Virology 88 (Pt 9): 2363–77. doi:10.1099/vir.0.82858-0. PMID 17698645. http://jgv.sgmjournals.org/content/journal/jgv/10.1099/vir.0.82858-0.
- Sourisseau M, Schilte C, et al. 2007. "Characterization of reemerging chikungunya virus". PLOS Pathogens 3 (6): e89. doi:10.1371/journal.ppat.0030089. PMC 1904475. PMID 17604450.
- Schilte C, Staikowsky F, et al. 2013. "Chikungunya virus-associated long-term arthralgia: a 36-month prospective longitudinal study.". PLOS Neglected Tropical Diseases 7 (3): e2137. doi:10.1371/journal.pntd.0002137. PMID 23556021.
- Mavalankar D, Shastri P, et al. 2008. "Increased Mortality Rate Associated with Chikungunya Epidemic, Ahmedabad, India". Emerging Infectious Diseases 14 (3): 412–5. doi:10.3201/eid1403.070720. PMC 2570824. PMID 18325255.
- Lahariya C and Pradhan SK 2006. "Emergence of chikungunya virus in Indian subcontinent after 32 years: A review". Journal of Vector Borne Diseases 43 (4): 151–60. PMID 17175699. http://www.mrcindia.org/journal/issues/434151.pdf.
- Staples JE and Fischer M 2014. "Chikungunya virus in the Americas--what a vectorborne pathogen can do". N. Engl. J. Med. 371 (10): 887–9. doi:10.1056/NEJMp1407698. PMID 25184860.
- Schwarz NG, Girmann M, et al. 2012. "Seroprevalence of antibodies against Chikungunya, Dengue, and Rift Valley fever viruses after febrile illness outbreak, Madagascar". Emerging Infectious Diseases 18 (11): 1780–6. doi:10.3201/eid1811.111036. PMC 3559170. PMID 23092548. http://wwwnc.cdc.gov/eid/article/18/11/11-1036_article.
- Fischer M and Staples JE 2014. "Notes from the Field: Chikungunya Virus Spreads in the Americas - Caribbean and South America, 2013-2014.". Morbidity and Mortality Weekly Report 63 (22): 500–501. PMID 24898168.
- Thiberville SD, Moyen N, et al. 2013 (2013). "Chikungunya fever: Epidemiology, clinical syndrome, pathogenesis and therapy". Antiviral Research 99 (3): 345–370. doi:10.1016/j.antiviral.2013.06.009. ISSN 01663542.
- Burt F, Ralph M, et al. 2012 (2012). "Chikungunya: a re-emerging virus". The Lancet 379 (9816): 662–671. doi:10.1016/S0140-6736(11)60281-X. ISSN 01406736. PMID 22100854.
- Weaver SC and Lecuit M 2015. "Chikungunya Virus and the Global Spread of a Mosquito-Borne Disease". New England Journal of Medicine 372 (13): 1231–1239. doi:10.1056/NEJMra1406035. ISSN 0028-4793.
- Powers, Ann. "Chikungunya". United States Centers for Disease Control and Prevention. http://wwwnc.cdc.gov/travel/yellowbook/2014/chapter-3-infectious-diseases-related-to-travel/chikungunya. Retrieved 12 May 2014.
- Mahendradas P, Ranganna SK, et al. 2008. "Ocular manifestations associated with chikungunya". Ophthalmology 115 (2): 287–91. doi:10.1016/j.ophtha.2007.03.085. PMID 17631967.
- Chhabra M, Mittal V, et al. 2008. "Chikungunya fever: a re-emerging viral infection". Indian Journal of Medical Microbiology 26 (1): 5–12. doi:10.4103/0255-0857.38850. PMID 18227590.
- Capeding MR, Chua MN, et al. 2013. "Dengue and other common causes of acute febrile illness in Asia: An active surveillance study in children.". PLOS Neglected Tropical Diseases 7 (7): e2331. doi:10.1371/journal.pntd.0002331. PMID 23936565.
- Caglioti C, Lalle E, et al. 2013. "Chikungunya virus infection: an overview.". The New Microbiologica 36 (3): 211–27. PMID 23912863.
- Morens DM and Fauci AS 2014. "Chikungunya at the door--déjà vu all over again?". New England Journal of Medicine 371 (10): 885–7. doi:10.1056/nejmp1408509. PMID 25029435.
- "Chikungunya—Fact sheet". European Centre for Disease Prevention and Control (ECDC). http://ecdc.europa.eu/en/healthtopics/chikungunya_fever/basic_facts/pages/factsheet_health_professionals.aspx. Retrieved 2013-12-17.
- Parashar D and Cherian S 2014 (2014). "Antiviral Perspectives for Chikungunya Virus". BioMed Research International 2014: 1–11. doi:10.1155/2014/631642. ISSN 2314-6133.
- Morrison TE 2014. "Reemergence of Chikungunya Virus". Journal of Virology 88 (20): 11644–11647. doi:10.1128/JVI.01432-14. ISSN 0022-538X.
- Gérardin P, Fianu A, et al. 2013. "Predictors of Chikungunya rheumatism: A prognostic survey ancillary to the TELECHIK cohort study.". Arthritis Research & Therapy 15 (1): R9. doi:10.1186/ar4137. PMID 23302155.
- Poh LNF, Sam C, et al. 2012. "Genotypic and Phenotypic Characterization of Chikungunya Virus of Different Genotypes from Malaysia". PLOS ONE 7 (11): e50476. doi:10.1371/journal.pone.0050476. ISSN 1932-6203.
- Roth A, Hoy D, et al. 2014. "Preparedness for Threat of Chikungunya in the Pacific". Emerging Infectious Diseases 20 (8). doi:10.3201/eid2008.130696. ISSN 1080-6040.
- Muniaraj M 2014. "Fading chikungunya fever from India: beginning of the end of another episode?". Indian Journal of Medical Research 139 (3): 468–70. PMC 4069744. PMID 24820844.
- "Number of cumulative cases 2013-2014". http://www.paho.org. Pan-American Health Organization (PAHO). 15 May 2015. http://www.paho.org/hq/index.php?option=com_docman&task=doc_download&Itemid=&gid=30198&lang=en. Retrieved 19 July 2015.
- Schuffenecker I, Iteman I, et al. 2006. "Genome microevolution of chikungunya viruses causing the Indian Ocean outbreak". PLOS Medicine 3 (7): e263. doi:10.1371/journal.pmed.0030263. PMC 1463904. PMID 16700631.
- Tsetsarkin KA, Vanlandingham DL, et al. 2007. "A Single Mutation in Chikungunya Virus Affects Vector Specificity and Epidemic Potential". PLOS Pathogens 3 (12): e201. doi:10.1371/journal.ppat.0030201. PMC 2134949. PMID 18069894.
- Liumbruno GM, Calteri D, et al. 2008. "The Chikungunya epidemic in Italy and its repercussion on the blood system". Blood Transfusions 6 (4): 199-210. PMID 19112735. http://www.ncbi.nlm.nih.gov/pubmed/19112735. Retrieved January 21, 2016.
- Robinson MC 1955. "An epidemic of virus disease in Southern Province, Tanganyika Territory, in 1952-53. I. Clinical features". Transactions of the Royal Society of Tropical Medicine and Hygiene 49 (1): 28–32. doi:10.1016/0035-9203(55)90080-8. PMID 14373834.
- Lumsden WH 1955. "An epidemic of virus disease in Southern Province, Tanganyika Territory, in 1952–53. II. General description and epidemiology". Transactions of the Royal Society of Tropical Medicine and Hygiene 49 (1): 33–57. doi:10.1016/0035-9203(55)90081-X. PMID 14373835.
- "Chikungunya fever diagnosed among international travelers—United States, 2005–2006". Morbidity and Mortality Weekly Report (United States Centers for Disease Control and Prevention (CDC)) 55 (38): 1040–2. 29 September 2006. PMID 17008866. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5538a2.htm.
- Carey DE 1971. "Chikungunya and dengue: a case of mistaken identity?". Journal of the History of Medicine and Allied Sciences 26 (3): 243–62. doi:10.1093/jhmas/XXVI.3.243. PMID 4938938.
- Cherian SS, Walimbe AM, et al. 2009. "Evolutionary rates and timescale comparison of Chikungunya viruses inferred from the whole genome/E1 gene with special reference to the 2005-07 outbreak in the Indian subcontinent". Infection, Genetics and Evolution, Journal of Molecular Epidemiology and Evolutionary Genetics of Infectious Diseases (Elsevier) 9 (1): 16–23. doi:10.1016/j.meegid.2008.09.004. PMID 18940268.
- "Chemical and Biological Weapons: Possession and Programs Past and Present". James Martin Center for Nonproliferation Studies. Middlebury College. April 9, 2002. http://cns.miis.edu/cbw/possess.htm. Retrieved June 18, 2014.