Chikungunya Chikungunya ( in the Makonde language " that leans downward " ) virus ( CHIKV ) is an insect - borne virus , of the genus " Alphavirus " , that is transmitted to humans by virus - carrying " Aedes " mosquitoes . There have been recent breakouts of CHIKV associated with severe illness . CHIKV causes an illness with symptoms similar to dengue fever . CHIKV manifests itself with an acute febrile phase of the illness lasting only two to five days , followed by a prolonged arthralgic disease that affects the joints of the extremities . The pain associated with CHIKV infection of the joints persists for weeks or months , or in some cases years . Signs and symptoms . The incubation period of Chikungunya disease is from two to four days . Symptoms of the disease include a fever up to , a petechial or maculopapular rash of the trunk and occasionally the limbs , and arthralgia or arthritis affecting multiple joints . Other nonspecific symptoms can include headache , conjunctival Infection , and slight photophobia . Typically , the fever lasts for two days and then ends abruptly . However , other symptoms — namely joint pain , intense headache , insomnia and an extreme degree of prostration — last for a variable period ; usually for about 5 to 7 days . Patients have complained of joint pains for much longer time periods depending on their age . Diagnosis . Common laboratory tests for chikungunya include RT - PCR , virus isolation , and serological tests . Causes . Chikungunya virus is indigenous to tropical Africa and Asia , where it is transmitted to humans by the bite of infected mosquitoes , usually of the genus " Aedes " . Chikungunya virus belongs to alphavirus genus of the Togaviridae family . It is an " Arbovirus " ( Ar - arthropod , bo - borne ) . CHIK fever epidemics are sustained by human - mosquito - human transmission . The word " chikungunya " is thought to derive from description in local dialect of the contorted posture of patients afflicted with the severe joint pain associated with this disease . The main virus reservoirs are monkeys , but other species can also be affected , including humans . Pathophysiology . This has been poorly researched to date . Human epithelial and endothelial cells , primary fibroblast s and monocyte - derived macrophages are susceptible to infection . Lymphoid and monocytoid cells , primary lymphocyte s and monocyte s and monocyte - derived dendritic cell s are not susceptible to infection . Viral entry occurs through pH - dependent endocytosis . Infection is cytopathic and associated with the induction of apoptosis in the infected cell . Infection is highly sensitive to the antiviral activity of type I and II interferon . Prevention . The most effective means of prevention are protection against contact with the disease - carrying mosquitoes and mosquito control . These include using insect repellent s with substances like DEET ( N , N - Diethyl - meta - toluamide ; also known as N , N ' - Diethyl - 3 - methylbenzamide or NNDB ) , icaridin ( also known as picaridin and KBR3023 ) , PMD ( p - menthane - 3 , 8 - diol , a substance derived from the lemon eucalyptus tree ) , or IR3535 . Wearing bite - proof long sleeves and trousers ( pants ) also offers protection . In addition , garments can be treated with pyrethroids , a class of insecticides that often has repellent properties . Vaporized pyrethroids ( for example in mosquito coils ) are also insect repellents . Securing screens on windows and doors will help to keep mosquitoes out of the house . In the case of the day - active " Aedes aegypti " and " Aedes albopictus " , however , this will have only a limited effect , since many contacts between the vector and the host occur outside . Treatment . There are no specific treatments for Chikungunya . There is no vaccine currently available . A Phase II vaccine trial , sponsored by the US Government and published in the " American Journal of Tropical Medicine and Hygiene " in 2000 , used a live , attenuated virus , developing viral resistance in 98 % of those tested after 28 days and 85 % still showed resistance after one year . A serological test for Chikungunya is available from the University of Malaya in Kuala Lumpur , Malaysia . Chloroquine is gaining ground as a possible treatment for the symptoms associated with Chikungunya , and as an anti - inflammatory agent to combat the arthritis associated with Chikungunya virus . A University of Malaya study found that for arthritis - like symptoms that are not relieved by aspirin and non - steroidal anti - inflammatory drugs ( NSAID ) , chloroquine phosphate ( 250 mg / day ) has given promising results . Research by an Italian scientist , Andrea Savarino , and his colleagues together with a French government press release in March 2006 have added more credence to the claim that chloroquine might be effective in treating chikungunya . Unpublished studies in cell culture and monkeys show no effect of chloroquine treatment on reduction of chikungunya disease . The fact sheet on Chikungunya advises against using aspirin , ibuprofen , naproxen and other NSAIDs that are recommended for arthritic pain and fever . DNA vaccine . DNA vaccination is a technique for protecting an organism against disease by injecting it with genetically engineered DNA to produce an immunological response . Nucleic acid vaccines are still experimental , and have been applied to a number of viral , bacterial and parasitic models of disease , as well as to several tumour models . DNA vaccines have a number of advantages over conventional vaccines , including the ability to induce a wider range of immune response types . A recent study supports a novel consensus - based approach to vaccine design for Chikungunya virus employing a DNA vaccine strategy . The vaccine cassette was designed based on CHIKV Capsid and Envelope specific consensus sequences with several modifications , including codon optimization , RNA optimization , the addition of a Kozak sequence , and a substituted immunoglobulin E leader sequence . Analysis of cellular immune responses , including epitope mapping , demonstrates that these constructs induces both potent and broad cellular immunity in mice . In addition , antibody ELISAs demonstrate that these synthetic immunogens are capable of inducing high titer antibodies capable of recognizing native antigen . Taken together , these results support further study of the use of consensus CHIKV antigens in a potential vaccine cocktail . Passive immunity . Antibodies isolated from patients recovering from Chikungunya fever have been shown to protect mice from infection . Prognosis . Recovery from the disease varies by age . Younger patients recover within 5 to 15 days ; middle - aged patients recover in 1 to 2 . 5 months . Recovery is longer for the elderly . The severity of the disease as well as its duration is less in younger patients and pregnant women . In pregnant women , no untoward effects are noticed after the infection . Ocular inflammation from Chikungunya may present as iridocyclitis , and have retinal lesions as well . Pedal oedema ( swelling of legs ) is observed in many patients , the cause of which remains obscure as it is not related to any cardiovascular , renal or hepatic abnormalities . Epidemiology . Chikungunya virus is an alphavirus closely related to the O ' nyong ' nyong virus , the Ross River virus in Australia , and the viruses that cause eastern equine encephalitis and western equine encephalitis . Chikungunya is generally spread through bites from " Aedes aegypti " mosquitoes , but recent research by the Pasteur Institute in Paris has suggested that Chikungunya virus strains in the 2005 - 2006 Reunion Island outbreak incurred a mutation that facilitated transmission by " Aedes albopictus " ( Tiger mosquito ) . Concurrent studies by arbovirologists at the University of Texas Medical Branch in Galveston , Texas , confirmed definitively that enhanced chikungunya virus infection of " Aedes albopictus " was caused by a point mutation in one of the viral envelope genes ( E1 ) . Enhanced transmission of chikungunya virus by " Aedes albopictus " could mean an increased risk for chikungunya outbreaks in other areas where the Asian tiger mosquito is present . A recent epidemic in Italy was likely perpetuated by " Aedes albopictus " . In Africa , chikungunya is spread via a sylvatic cycle in which the virus largely resides in other primates in between human outbreaks . On 28 May 2009 in Changwat Trang of Thailand where the virus is endemic , the provincial hospital decided to deliver by Caesarean section a male baby from his Chikungunya - infected mother — Khwanruethai Sutmueang , 28 , a Trang native — in order to prevent mother - foetus virus transmission . However , after delivering the baby , the physicians discovered that the baby was infected with Chikungunya virus , and put him into intensive care because the infection had left the baby unable to breathe by himself or to drink milk . The physicians presumed that Chikungunya virus might be able to be transmitted from a mother to her foetus ; however , there is no laboratory confirmation for this presumption . History . The name is derived from the Makonde word meaning " that which bends up " in reference to the stooped posture developed as a result of the arthritic symptoms of the disease . The disease was first described by Marion Robinson and W . H . R . Lumsden in 1955 , following an outbreak in 1952 on the Makonde Plateau , along the border between Mozambique and Tanganyika ( the mainland part of modern day Tanzania ) . According to the initial 1955 report about the epidemiology of the disease , the term ' chikungunya ' is derived from the Makonde root verb " kungunyala " , meaning to dry up or become contorted . In concurrent research , Robinson glossed the Makonde term more specifically as " that which bends up . " Subsequent authors apparently overlooked the references to the Makonde language and assumed that the term derived from Swahili , the lingua franca of the region . The erroneous attribution of the term as a Swahili word has been repeated in numerous print sources . Many other erroneous spellings and forms of the term are in common use including " Chicken guinea " , " Chicken gunaya , " and " Chickengunya " . Since its discovery in Tanganyika , Africa , in 1952 , chikungunya virus outbreaks have occurred occasionally in Africa , South Asia , and Southeast Asia , but recent outbreaks have spread the disease over a wider range . Use as a biological weapon . Chikungunya was one of more than a dozen agents that the United States researched as potential biological weapon s before the nation suspended its biological weapons program .