Chikungunya fever is a viral infectious disease caused by the chikungunya virus, primarily transmitted through bites from infected Aedes mosquitoes. Clinically, it manifests as fever, rash, and joint and muscle pain. Most patients recover within a week, but in 30%–40% of cases, joint pain may persist for months or even years, significantly impacting quality of life.

1. How Is Chikungunya Virus Transmitted?

Chikungunya virus is mainly spread by Aedes mosquitoes, particularly Aedes aegypti and Aedes albopictus. When a mosquito bites an infected person, it can transmit the virus to others after an incubation period of 2–10 days.

The core transmission cycle is "human → mosquito → human." In the first week of illness, infected individuals have high levels of the virus in their blood, increasing the risk of transmission via mosquito bites. However, the virus is not spread through casual human contact, coughing, or sneezing.

In rare cases, the virus can be transmitted through transfusion or accidental exposure to infected blood if the viral load is high. Pregnant women can trans

2. Where Is Chikungunya Fever Prevalent?

As of December 2024, local transmission of chikungunya fever has been reported in 119 countries and regions. Major outbreaks and sporadic cases have occurred in the Americas, Asia, and Africa. Between January and June 2025, approximately 220,000 cases and 80 deaths were reported across 14 countries or regions.

China reported its first imported case in 2008, with local outbreaks occurring in Guangdong and Yunnan, but it has not established stable endemic zones. In July 2025, a local outbreak in Foshan, Guangdong, was triggered by an imported case. The epidemic is currently at a critical stage, and public cooperation is essential—eliminating standing water, controlling mosquitoes, and preventing bites are key measures.

3. What Are the Clinical Symptoms?

Most infected individuals develop symptoms 3–7 days (range: 1–12 days) after being bitten. Common symptoms include sudden fever and joint pain, especially in the wrists, ankles, toes, knees, and shoulders. Severe joint pain can limit mobility.

Other symptoms may include headache, muscle pain, joint swelling, rash, nausea, and fatigue. Rarely, complications may affect the eyes, heart, or nervous system. These symptoms are similar to dengue or Zika virus infections, increasing the risk of misdiagnosis.

High-risk groups for severe illness include newborns infected around the time of birth, elderly individuals (65+), and those with underlying conditions such as hypertension, diabetes, or heart disease. Most people recover within a week, but joint pain may last months or even years in some cases.

4. How Is Chikungunya Diagnosed?

Chikungunya should be considered in patients with acute fever and joint pain, especially those who recently travelled to affected regions. Laboratory testing is required for confirmation.

Methods include: 

• Virus isolation

• Viral RNA testing

• Virus-specific antibody testing

Detection of chikungunya RNA or virus from serum confirms diagnosis. Antibodies (IgM, IgG) typically rise after day 5 of illness. If acute-phase samples test negative, convalescent samples should be tested: seroconversion of IgG or a 4-fold increase in antibody titers confirms infection. IgM results may show false positives and should not be solely used for diagnosis.

5. How Is Chikungunya Treated?

There is no specific antiviral treatment. Management is supportive:

• Adequate rest

• Hydration

• Over-the-counter pain relievers like acetaminophen

Avoid aspirin and NSAIDs (e.g., ibuprofen) until dengue is ruled out to reduce bleeding risk.

6. How to Prevent Chikungunya

The best prevention is avoiding mosquito bites:

• Use insect repellent

• Wear long sleeves and pants

• Treat clothing with 0.5% permethrin

• Stay in homes with screens

• Sleep under mosquito nets

7. How to Control Chikungunya Virus Transmission

Control involves:

• Eliminating mosquito breeding sites

• Emptying water containers at least every 5 days

• Proper waste disposal

During outbreaks:

• Spraying insecticides

• Treating mosquito-resting surfaces

• Treating water to kill larvae

8. Is There a Vaccine?

Currently, no licensed vaccine is available in China. Since the country is not endemic, the general population lacks immunity and is widely susceptible. Personal protection and bite prevention are the most effective strategies. Individuals with suspected symptoms should seek medical care and prevent mosquito bites.

9. What Should Travellers Be Aware Of?

Before travel:

• Check health advisories of destination countries

• Some groups (e.g., pregnant women) may consider postponing travel

During travel:

• Carry repellents with DEET, picaridin, oil of lemon eucalyptus, or IR3535

• Use permethrin-treated clothing and gear

• Sleep under nets, wear protective clothing, and stay in screened accommodations

After travel:

• Continue mosquito precautions for 2 weeks to prevent local transmission

• If symptoms like fever, rash, joint or muscle pain occur, seek medical attention and report travel history

• Isolate from mosquitoes to avoid infecting others

10. How Can Individuals and Families Prevent Mosquitoes?

(1) Personal Protection

• In affected areas, wear light-colored long sleeves and pants

• Use repellents and mosquito patches

• Install screens and use mosquito nets at night

(2) Indoor Water Management

• Change the water in hydroponic plants every 3–5 days

• Rinse containers and plant roots

• Inspect areas like water dispensers and refrigerator trays

(3) Roofs, Balconies, and Surroundings

• Clean rooftop drains, avoid clogs

• Remove or cover flowerpots, foam boxes, and unused containers

• Cover water tanks, clear debris

• Seal bamboo tubes, tree holes, and use fish in lotus ponds

• Drain the air conditioner water, puncture or store tires properly

• Seal storm drains, convert open drains where possible

(4) Indoor Mosquito Control

• Use aerosol insecticides, liquid repellents, and mosquito coils

• When using smoke insecticides, close windows, evacuate for 30 minutes, then ventilate before re-entry

• Use electric mosquito swatters, traps, or UV lights

11. Common Mosquito Breeding Grounds and Cleanup Methods

(1) Homes and Personal Workspaces

Focus on:

• Aquatic plants

• Plant trays

• Buckets

• Idle bottles and jars

• Water tanks

• Yard drains

Actions: Drain water, cover containers, switch to soil planting, larvicides, clear drainage

(2) Communities, Workplaces, Construction Sites

Clean breeding sites inside and out, especially:

• Greenbelts

• Parking lots

• Trash and debris storage areas

• Basement sump pits

• Drains and stairwells
  Actions: Clean corners, remove containers, add soil, apply larvicides

(3) Public Spaces and Outdoor Environments

Target areas:

• Greenbelts

• Public parking lots

• Waste piles

• Abandoned tires

• Municipal pipeline wells

• Building depressions

Actions: Remove trash, drain stagnant water, use soil fill, larvicides

(4) Other High-Risk Breeding Grounds
Focus on:

• Vacant houses, especially old homes in urban villages

• Outdoor trash heaps

• Idle lots and hidden spaces
  Thorough cleanup can greatly reduce mosquito breeding.

Source: Chinese Centre for Disease Control and Prevention

Editor: Ye Ke