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A mosquito-borne virus more common in South America has been detected in the United States. Health officials say the chikungunya virus has been identified in a patient living in the suburbs of New York City who began experiencing symptoms in August. Authorities say it’s the first locally acquired case identified in any state since 2019, meaning the patient didn’t travel outside the country before becoming infected. It’s also the first locally acquired case that New York has ever seen [1, 2, 3].

What is chikungunya?

Chikungunya is a viral disease transmitted to humans by mosquitoes, notably the Aedes aegypti and Aedes albopictus species. The virus is more common in tropical and subtropical regions, particularly in Africa, Asia, the Caribbean, Central America and South America, but local transmission has very rarely occurred in the United States [1, 4].

Chikungunya gets its name from the Makonde language, meaning “bent over in pain,” reflecting the severe joint discomfort it often causes. Transmission to humans occurs only through the bite of an infected mosquito — direct person-to-person transmission does not occur [5].

What are the symptoms?

Common symptoms include sudden onset of fever, severe joint pain (often in hands and feet), muscle pain, headache, nausea, fatigue and rash. Symptoms typically appear 3-7 days after an infected mosquito bite and last about a week in most cases, though joint pain can persist for months or even years in some individuals [6, 7].

Treatment and vaccine

There is currently no specific antiviral treatment for chikungunya. Care is supportive — rest, fluids and pain relievers help manage fever and joint pain. There is no general vaccine available for the public, but immunization may be recommended for select travelers to endemic regions. Most people recover fully, but chronic pain can last for months [7].

Geographic distribution

Chikungunya is endemic in Africa, Asia, the Caribbean, Central America and South America. It is not typically found in the U.S., Canada, Chile or Uruguay except for rare travel-related or very isolated local transmission events [2].

Risk groups and mortality

Chikungunya is rarely fatal, but certain groups — infants, older adults (65+) and people with chronic conditions (high blood pressure, diabetes, heart disease) — are at elevated risk for severe disease and complications. Serious complications or death, though extremely uncommon, can occur in these groups [7, 8].

Transmission risk in the U.S.

While local transmission is possible if mosquitoes bite an infected person and subsequently transmit the virus to others, outbreaks have been rare in the U.S. Officials currently assess the risk of widespread transmission in New York as very low due to cooler temperatures limiting mosquito activity. For the general public, vigilance is recommended but panic is unwarranted — the overall risk in temperate U.S. states remains low unless infected mosquitoes become established in the local environment [8, 9].

Long-term complications

Most patients recover fully within weeks, but about one-third to nearly half may suffer from prolonged joint pain and related symptoms for months or years. Long-term chikungunya complications can significantly impair quality of life, requiring multidisciplinary management to address both physical and psychological impacts. Chronic joint pain and related symptoms are the hallmark of long-term chikungunya disease, especially in vulnerable populations [10, 11].

Differences from other mosquito-borne viruses

All three viruses — chikungunya, dengue and Zika — are transmitted by the same mosquito species, and symptom overlap exists. However, key differences help clinicians differentiate them:

• Dengue can cause more severe acute illness with risk of hemorrhage, thrombocytopenia (low platelets) and shock, sometimes fatal
• Zika usually causes mild symptoms but is particularly concerning for pregnant women due to risk of severe congenital birth defects; conjunctivitis (red eyes) is common in Zika but less so in chikungunya and dengue

This symptom comparison helps clinicians differentiate the diseases, which is important since treatment and risk monitoring differ significantly [1, 12, 13].

Testing and diagnosis

Testing is available through commercial labs, state public health departments and the CDC Arbovirus Diagnostic Laboratory (for confirmatory testing). Health care providers typically consult state or local health departments to submit specimens and confirm results, especially when local transmission may be suspected [14, 15].

Mosquito control effectiveness

Mosquito control measures can be effective in reducing mosquito populations and thereby limiting the spread of mosquito-borne diseases like chikungunya, dengue and Zika, but their long-term success depends on multiple factors.

Control methods can reduce mosquito populations temporarily, helping prevent outbreaks during peak transmission seasons. However, sustaining this reduction is challenging without ongoing effort and resources. Most effective control programs use Integrated Pest Management, which combines removing mosquito breeding habitats (standing water sources), using structural barriers like window screens and bed nets, targeting mosquito larvae through larvicides and adult mosquito control via insecticides [16, 17].

Several challenges limit effectiveness. Mosquitoes like Aedes aegypti breed in numerous small, scattered locations, making complete habitat elimination difficult. Adulticide spraying provides immediate relief but does not offer long-term mosquito population control as mosquitoes re-invade treated areas. Mosquitoes are highly mobile and can quickly repopulate an area if breeding sites persist. Insecticide resistance among mosquitoes is an increasing problem reducing effectiveness of chemical controls [16, 17, 18].

Sustained mosquito control requires political commitment, funding, trained personnel and community engagement to monitor and eliminate breeding sites regularly. Past successes, such as early 20th-century yellow fever control through combined vaccination and mosquito control, show that comprehensive, well-resourced and sustained efforts can effectively interrupt transmission [16, 17].

While mosquito control can reduce disease spread and mosquito populations, no measure is 100% effective alone. Integrated, sustained control programs combining habitat elimination, barriers, larval and adult mosquito control, supported by surveillance and community participation, are essential to maximize impact on reducing chikungunya and other mosquito-borne diseases [17, 18].

Sources

[1] https://www.usatoday.com/story/news/nation/2025/10/15/chikungunya-virus-mosquito-new-york/86706056007/

[2] https://www.nytimes.com/2025/10/14/nyregion/chikungunya-first-case-long-island.html

[3] https://www.nbcnews.com/news/us-news/new-york-health-officials-confirm-states-first-locally-acquired-case-c-rcna237734

[4] https://www.cdph.ca.gov/Programs/CID/DCDC/CDPH%20Document%20Library/ChikungunyaFactSheet.pdf

[5] https://www.paho.org/en/topics/chikungunya

[6] https://www.cdc.gov/chikungunya/about/index.html

[7] https://www.cdc.gov/chikungunya/symptoms-diagnosis-treatment/index.html

[8] https://www.pbs.org/newshour/health/new-york-state-confirms-first-locally-acquired-case-of-chikungunya-virus

[9] https://nypost.com/2025/10/15/us-news/new-york-health-officials-confirm-states-first-locally-acquired-case-of-chikungunya-virus/

[10] https://pmc.ncbi.nlm.nih.gov/articles/PMC8887759/

[11] https://www.sciencedirect.com/science/article/abs/pii/S1477893920300867

[12] https://www.cdc.gov/chikungunya/hcp/clinical-signs/index.html

[13] https://economictimes.com/news/new-updates/what-is-the-difference-between-zika-virus-dengue-chikungunya-know-symptoms/articleshow/96323332.cms

[14] https://www.cdc.gov/chikungunya/hcp/diagnosis-testing/index.html

[15] https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Chikungunya-Virus-Serology

[16] https://www.ncbi.nlm.nih.gov/books/NBK585173/

[17] https://www.epa.gov/mosquitocontrol/success-mosquito-control-integrated-approach

[18] https://www.mosquito.org/mosquito-control/