Chikungunya is a self-remitting febrile viral disease that has been associated with frequent outbreaks in tropical countries of Africa, Europe, America, and Southeast Asia.
What is Chikungunya Virus?
Chikungunya virus is an insect-borne viral illness that causes sudden onset fever, arthralgia, and rash. It is transmitted to humans through day-biting mosquitoes that belong to the Aedes genus.
- The term “Chikungunya” often refers to both the virus (CHIKV) and the illness or fever (CHIKF) caused by this virus.
- It was derived from the African dialect Swahili or Makonde and translates as “to be bent over”; in Congo, it is referred to as “buka-buka,” which means “broken-broken.”
- These terms refer to the “stooped-over posture” exhibited by individuals with the disease as a consequence of severe chronic incapacitating arthralgias.
- Humans are the primary host of the chikungunya virus during epidemic periods.
Pathophysiology
The exact pathophysiology of Chikungunya virus remains to be investigated. To date, most of the research in this field has been from the Indian subcontinent and other Asian countries.
- Using a murine model, Lum et al have shown that anti–Chikungunya virus antibodies were elicited early in the course of the illness and were directed against the C-terminus of the viral E2 glycoprotein.
- They showed that both natural and Chikungunya virus infection–induced specific antibodies were essential for controlling Chikungunya virus infections.
- The exact mechanism of entry of the virus into mammalian cells is under investigation.
- Bernard et al evaluated this mechanism and found that Chikungunya virus enters mammalian epithelial cells via a clathrin-independent, Esp-15–dependent, dynamin 2–dependent route and requires an endocytic pathway in combination with other unknown pathways.
- Aedes aegypti was known to be the primary vector for Chikungunya infection in India and other countries during the 2006-2010 epidemics.
- Analysis of a 2016 outbreak in Brazil revealed two novel mutations in the virus (K211T in E1 and V156A in E2); these mutations enhanced viral fitness, as they could infect host cells independent of cholesterol, causing the outbreak to become an epidemic.
- Further research in this field would undoubtedly provide a better understanding of the in vivo interactions between Chikungunya virus and immune cells and shed light on the immunopathogenesis.
Statistics and Incidences
Numerous Chikungunya epidemics have been reported in several countries in Southern and South East Asia.
- The first Asian epidemic was reported in Bangkok, Thailand, in 1958, continued until 1964, and reappeared after a hiatus in the mid-1970s and declined again in 1976.
- The most severe Chikungunya fever outbreak was reported in 2006 on Reunion Island, where one-third of the population was infected, resulting in 237 deaths.
- Around the same time, a historical outbreak on the Indian subcontinent involved 1.42 million people, with high morbidity rates.
- According to figures from 2013-2014 from the Centers for Disease Control and Prevention (CDC), European Center for Disease Prevention and Control (ECDC), and the Pan American Health Organization (PAHO), several imported cases of travel-related Chikungunya fever have been reported in the United States, Caribbean islands, Britain, France, Germany, Sweden, Portugal, Canary Islands, and the archipelagos off the coast of Western Africa.
- Chikungunya virus emerged in America in late 2013 and has continued to spread to neighboring countries.
- As of 2017, about 1.8 million cases had been reported from 44 countries.
- A total of 124 cases of Chikungunya virus disease (116 from US states and 8 from US territories) were reported to ArboNET in 2018.
- As of August 1, 2019, a total of 42 Chikungunya virus disease cases had been reported in the United States and its territories in 2019.
Cause
Chikungunya virus is an alpha virus that belongs to the Togaviridae family.
- It is a single-stranded RNA virus and is approximately 11.8 kb long with a capsid and a phospholipid envelope.
- Chikungunya virus is transmitted to humans through day-biting mosquitoes that belong to the Aedes genus.
- Being an arbovirus, the virus is maintained in the environment between humans or other animals and mosquitoes.
- Humans serve as major reservoirs during epidemics.
- During inter-epidemic quiescence in Africa, the virus is thought to be maintained in an epizootic cycle that involves vertebrates such as monkeys, rodents, and birds.
- In Africa, the virus is maintained in a sylvatic cycle among wild primates, monkeys and, wild Aedes mosquitoes (Aedes furcifer, Aedes taylori, Aedes luteocephalus, Aedes africanus, Aedes neoafricanus).
- In Asia, the virus is maintained in an urban cycle involving A aegypti mosquitoes and humans.
Clinical Manifestation
Symptoms usually begin 3–7 days after being bitten by an infected mosquito.
- Fever. One of the most common symptoms is high-grade fevers (up to 105°F).
- Arthralgia. The arthralgias are usually polyarticular and migratory and frequently involve the small joints of the hands, wrist, and ankle, with lesser involvement of the large joints such as the knee or shoulder with associated arthritis; joint pain is worse in the morning, gradually improving with slow exercise and movement but exacerbated by strenuous exercise.
- Cutaneous manifestations. Individuals with Chikungunya fever frequently present with a flushed appearance involving the face and trunk, followed by a diffuse erythematous maculopapular rash of the trunk and extremities, sometimes involving the palms and soles; the rash gradually fades; may evolve into petechiae, urticaria, xerosis, or hyper melanosis; or resolves with desquamation.
- Neurological manifestations. In the acute phase of the illness (reported during the outbreak in the Indian Ocean in 2005-2006), 23 patients presented with neurological symptoms associated with abnormal CSF tests and positive CSF immunoglobulin M (IgM) or reverse-transcriptase polymerase chain reaction (RT-PCR) for Chikungunya virus.
- Others. Rare presentations include severe rheumatoid arthritis, neuroretinitis, uveitis, hearing loss, myocarditis, and cardiomyopathy.
Assessment and Diagnostic Findings
Diagnostic testing is available through a few commercial laboratories, many state health departments, and the Centers for Disease Control and Prevention.
- Serological testing. Chikungunya virus–specific IgM antibodies usually appear upon cessation of viremia, usually by day 5-7 into the illness, and stay positive for 3-6 months; immunoglobulin G (IgG)–neutralizing antibodies appear after 7-10 days and may persist for several months; these antibodies are detected with an enzyme-linked immunoassay (ELISA) test that is available through the CDC and several state health departments.
- Viral culture. Chikungunya virus may be isolated in culture within the first 3 days of illness during the period of active viremia by inoculation of blood into mice or mosquitoes; culture-based detection is also available through the CDC.
- Molecular diagnostics. RT-PCR has been standardized using both structural and nonstructural domains of the Chikungunya virus genome and is available through the CDC.
Medical Management
There is no specific antiviral therapy or vaccine for chikungunya virus infection. Treatment is focused on relieving the symptoms.
- Relieve joint pain and fever. Treatment is for symptoms and can include rest, fluids, and use of non-steroidal anti-inflammatory drugs (NSAIDs) to relieve acute pain and fever.
- Monitor glucose levels. Poor glycemic control in patients with diabetes who have Chikungunya infection has been reported; it is important to monitor the blood glucose closely in these patients.
- Conservative treatment. Conservative treatment includes management of electrolyte imbalance, prerenal azotemia, and hemodynamic monitoring based on severity of illness.
Nursing Management
Nursing care of a patient with Chikungunya virus include:
Nursing Assessment
Assessment of a patient with Chikungunya include:
- History. Chikungunya fever is an acute febrile illness with an incubation period of 3-7 days; it affects all age groups and both sexes equally, with an attack rate (percentage of individuals who develop illness after infection) of 40%-85%.
- Physical examination. Clinical examination reveals high-grade fevers (up to 105°F), pharyngitis, conjunctival suffusion, conjunctivitis, and photophobia; cervical or generalized lymphadenopathy has also been reported in rare cases.
Nursing Diagnosis
Based on the assessment data, the following are some of the nursing diagnoses for patients with Chikungunya:
- Hyperthermia related to increase in metabolic demand.
- Deficient fluid volume related to dehydration.
- Pain related to joint inflammation.
- Impaired skin integrity related to cutaneous manifestations.
Nursing Care Planning and Goals
The major nursing care planning goals in a patient with Chikungunya virus include:
- Patient will improve the body temperature.
- Patient will restore an adequate amount of fluid volume.
- Patient will experience relief from pain.
- Patient will show an improvement of the integrity of the skin.
Nursing Interventions
The nursing interventions for a patient with Chikungunya virus are:
- Improve the body temperature. Eliminate excess clothing and covers; give antipyretic medications as prescribed; perform tepid sponge bath, and modify cooling measures based on the patient’s physical response.
- Restore adequate amount of fluid volume. Assess skin turgor and oral mucous membranes for signs of dehydration; assess color and amount of urine and report urine output less than 30 ml/hr for 2 consecutive hours; urge the patient to drink the prescribed amount of fluid, and administer parenteral fluids as prescribed.
- Relief from pain. Acknowledge reports of pain immediately; provide rest periods to promote relief, sleep, and relaxation; and provide analgesics as ordered, evaluating the effectiveness and inspecting for any signs and symptoms of adverse effects.
- Improve the integrity of the skin. Monitor site of impaired tissue integrity at least once daily for color changes, redness, swelling, warmth, pain, or other signs of infection; provide tissue care as needed; tell the patient to avoid rubbing and scratching; provide gloves or clip the nails if necessary; administer antibiotics as ordered.
Evaluation
Nursing Goals are met as evidenced by:
- Improve the body temperature.
- Restore adequate amount of fluid volume.
- Relief from pain.
- Improve integrity of the skin.
Documentation Guidelines
Documentation in a patient with Chikungunya virus include the following:
- Individual findings, including factors affecting, interactions, nature of social exchanges, specifics of individual behavior.
- Cultural and religious beliefs, and expectations.
- Plan of care.
- Teaching plan.
- Responses to interventions, teaching, and actions performed.
- Attainment or progress toward the desired outcome.
Summary
Here are some of the most important points about Chikungunya virus:
- Chikungunya fever is a self-remitting febrile viral illness that has been associated with frequent outbreaks in tropical countries of Africa and Southeast Asia.
- Chikungunya virus is transmitted to humans through day-biting mosquitoes that belong to the Aedes genus.
- Numerous Chikungunya epidemics have been reported in several countries in Southern and Southeast Asia.
- Chikungunya virus is an alphavirus that belongs to the Togaviridae family.
- Symptoms usually begin 3–7 days after being bitten by an infected mosquito, and these include fever, arthralgia, cutaneous manifestations, and neurological manifestations.
- There is no specific antiviral therapy for chikungunya virus infection.
References
Sources and references for this Chikungunya study guide:
• Centers for Disease Control and Prevention. (2019, Sept 19). Chikungunya. Retrieved from https://www.cdc.gov/chikungunya/index.html
• Natesan, S.K. (2019, Aug 1). Chikungunya virus. Retrieved from https://emedicine.medscape.com/article/2225687-overview