Chikungunya Outbreak Expands Globally, Prompting Urgent Research and Vaccine Development

The chikungunya virus (CHIKV) outbreak has dramatically expanded to over 110 countries, putting approximately 5.6 billion people at risk. This mosquito-borne alphavirus, primarily transmitted by Aedes mosquitoes, causes fever, severe joint pain, rash, and muscle aches. As the virus reaches new territories, including temperate regions, the pharmaceutical industry is ramping up efforts to develop effective treatments and vaccines.

Global Spread and Outbreak Epicenters

Since the beginning of 2025, major chikungunya outbreaks have been reported in Reunion, Mayotte, and Mauritius. Notably, the virus has reached temperate regions earlier than anticipated, with locally acquired cases reported in mainland France's Grand Est and southeastern areas. This surge is attributed to multiple factors, including:

• Expanded Aedes mosquito habitats due to climate change
• Increased urbanization
• International travel facilitating virus spread
• Low immunity in populations after years without outbreaks
• Challenges in early detection due to inconsistent surveillance and limited diagnostic resources

Treatment and Vaccine Landscape

As of 2025, no specific antiviral treatments for chikungunya virus exist, with care primarily focused on symptom relief. However, vaccine development has made significant progress:

1. IXCHIQ: A live-attenuated vaccine approved for adults, with restrictions for the elderly.
2. VIMKUNYA: A single-dose virus-like particle vaccine approved for ages 12 and up.

Neither vaccine is yet widely available globally or in China. Control efforts continue to rely heavily on mosquito management, early detection, and public awareness campaigns.

Research Advancements and Industry Support

Sino Biological has emerged as a key player in supporting chikungunya virus research. The company has rapidly developed recombinant E1 and E2 proteins (UVE/CHIKV/2024/RE/CNR_79903) along with specific antibodies, providing crucial tools for researchers working on vaccine development, antiviral therapies, and immunodiagnostic assays.

Recent studies utilizing Sino Biological's products have yielded important insights:

• Liu T. and Gu D. developed an aptamer-based TRFIA assay to study the binding affinity and specificity of novel peptides to CHIKV E2 antigens.
• Tamburini B. et al. investigated viral antigen acquisition in various cell types in mice infected with recombinant CHIKV E2 antigen.
• Lim H. and Kim K. demonstrated that CHIKV EI/II protein or N-linked glycan mutant E proteins induced lower humoral immune responses than the full-length E protein.
• Wang T. et al. reported that EILV/CHIKV-vaccinated macaques exhibited stronger neutralization titers and higher CHIKV E2 binding IgG responses.

These studies underscore the importance of continued research and development in combating the global chikungunya outbreak. As the virus continues to spread, the pharmaceutical industry remains focused on developing innovative solutions to address this growing public health challenge.