Chikungunya

Chikungunya virus (CHIKV) is an enveloped, positive-sense, single-stranded RNA virus belonging to the genus Alphavirus in the family Togaviridae. It possesses a positive-sense, single-stranded RNA genome of approximately 11.8 kb, which encodes two polyproteins: nonstructural proteins (nsP1-nsP4) responsible for viral replication, and structural proteins (C, E3, E2, 6K, and E1) that comprise the viral capsid and envelope. The capsid protein (C) packages the viral RNA and facilitates nucleocapsid assembly. The virus is encapsidated by a host-derived lipid bilayer, within which the E1 and E2 glycoproteins are embedded. These glycoproteins are essential for host cell attachment and membrane fusion and are key targets for neutralizing antibodies and diagnostic assays.

Figure 1. Schematic diagram of the CHIKV genome

Chikungunya virus (CHIKV) is primarily transmitted by Aedes mosquitoes, particularly Aedes aegypti and Aedes albopictus. Infected individuals typically experience a sudden onset of high fever, severe joint pain, headache, muscle aches, rash, and fatigue. While most symptoms resolve within a week, a significant number of patients may experience chronic joint pain that persists for months. This long-term discomfort can significantly impact quality of life, work productivity, and overall health, particularly for the elderly and those with pre-existing medical conditions. While the mortality rate is low (approximately 1 in 1,000), the disease burden can be substantial.

Due to globalization, increased travel, and climate change, the habitat of Aedes mosquitoes has expanded significantly. According to the World Health Organization (WHO), by the end of 2024, local transmission of chikungunya virus had been reported in over 119 countries and territories.

As of July 23, 2025, the Pan American Health Organization (PAHO) had recorded over 201,000 cases in the Americas, with the highest incidence rates in Argentina, Bolivia, Brazil, Paraguay, and Peru.In the United States, the major circulating genotypes include:West African lineage; East, Central, and Southern African (ECSA) lineage; Asian lineage. The following table compares the three main genotypes of chikungunya virus:

As can be seen in the table, E1 has been identified as a key mutation hotspot, posing a significant challenge to chikungunya research and vaccine development. In contrast, the E2 structural protein exhibits conserved sequences across different genotypes, making it a reliable target for viral diagnostics.

A major clinical challenge is that the symptoms of chikungunya virus closely resemble those of dengue and Zika virus infection, leading to diagnostic uncertainty. Although two vaccines against chikungunya virus have been approved or recommended by the World Health Organization for use in high-risk populations, they are not yet widely available or deployed.

Therefore, symptomatic and supportive care remain the only medical options. fundamental research into Chikungunya virus pathogenesis, vaccine responses, and immune memory is urgently needed. In this context, accurate protein and antibody serum detection is crucial for early detection and clinical differentiation.

In response to the aggressive Chikungunya virus mutant strain, Beta Lifescience provides a comprehensive range of recombinant Chikungunya virus proteins and supporting antibodies for use in ELISA, chromatography detection, and immunoblotting to support the development of Chikungunya virus vaccines, antiviral drugs, and diagnostic reagents.

References

[1] Huerta Albarran R, Weber A, Aviles Robles M, et al. Chikungunya virus infection: A scoping review highlighting pediatric systemic and neurologic complications[J]. Semin Pediatr Neurol, 2025, 54: 101213.

[2] Freppel W, Silva L A, Stapleford K A, et al. Pathogenicity and virulence of chikungunya virus[J]. Virulence, 2024, 15(1): 2396484.

[3] An W, Ge N, Cao Y, et al. Recent progress on chikungunya virus research[J]. Virol Sin, 2017, 32(6): 441-453.

[4] Santiago R A, Bavaresco S P P, Citrangulo S G, et al. Clinical manifestations associated with the chronic phase of Chikungunya Fever: A systematic review of prevalence[J]. PLoS Negl Trop Dis, 2025, 19(2): e0012810.