The first vaccine against chikungunya virus (CHIKV) has now been licensed; however, due to a limited knowledge of the underlying global burden, its potential to reduce disease burden remains unknown. We used data from seroprevalence studies, observed cases and mosquito distributions to quantify the underlying CHIKV burden in 180 countries and territories, and we explored the potential impact of vaccination campaigns. We estimate that 104 countries have experienced CHIKV transmission, covering 2.8 billion people, and that, in epidemic settings, the mean duration between outbreaks is 6.2 years, with 8.4% of the susceptible population infected per outbreak. Globally, there are 35 million annual infections, mainly in Southeast Asia, Africa and the Americas. Assuming a vaccine efficacy against disease of 70% and a protection against infection of 40%, vaccinating 50% of individuals over 12 years of age in places and times where the virus circulates would avert 4,436 infections, 0.34 deaths a

Chikungunya virus (CHIKV) infection causes acute febrile illness that frequently progresses to chronic arthralgia. Although monocytes are CHIKV targets, whether viral exposure drives their differentia...

Nature Microbiology, Published online: 30 September 2026; doi:10.1038/s41564-026-02468-3This study extends the Pango lineage nomenclature system beyond SARS-CoV-2, introducing a dynamic framework for tracking and communicating viral diversity, demonstrated through its application to CHIKV.

The licensing of the first chikungunya virus (CHIKV) vaccine in Brazil marked a pivotal moment in the global fight against this expanding arbovirus. Over the past two decades, CHIKV has emerged as one...

Altas temperaturas e chuvas desordenadas estão entre desafios. Ministério da Saúde tem adotado novas tecnologias para controle das arboviroses ante os fenômenos climáticos

Widely spread around the globe, chikungunya virus (CHIKV) is a mosquito-borne virus that can cause severe acute disease, sometimes followed by debilitating chronic joint pain. This study provides esti...

A recent chikungunya outbreak affected 1.5 million cases in more than 60 countries. The virus causes low mortality but moderate to severe morbidities such as high fever, myalgia, and polyarthritis. Th...

Chikungunya virus (CHIKV) imposes a substantial global health burden, characterized by arthralgia that can persist for years, neurological complications, and potentially fatal outcomes in vulnerable p...

Chikungunya virus leads to chronic arthritis-like symptoms in a significant number of infected individuals. In a cohort of CHIKV-infected individuals with persistent arthralgia, Agarwal et al. find an...

Chikungunya virus (CHIKV) infection is typically not life threatening but may, in rare cases, affect the central nervous system (CNS). In three coh...

Infection by chikungunya virus (CHIKV), a mosquito-borne alphavirus, causes severe polyarthralgia and polymyalgia, which can last in some people for months to years. Chronic CHIKV disease signs and symptoms are associated with the persistence of viral nucleic acid and antigen in tissues. Like humans and nonhuman primates, CHIKV infection in mice results in the development of robust adaptive antiviral immune responses. Despite this, joint tissue fibroblasts survive CHIKV infection and can support persistent viral replication, suggesting that they escape immune surveillance. Here, using a recombinant CHIKV strain encoding a chimeric protein of VENUS fused to a CD8+ T cell epitope, SIINFEKL, we observed a marked loss of both MHC class I (MHC-I) surface expression and antigen presentation by CHIKV-infected joint tissue fibroblasts. Both in vivo and ex vivo infected joint tissue fibroblasts displayed reduced cell surface levels of H2-Kb and H2-Db MHC proteins while maintaining similar levels of other cell surface proteins. Mutations within the methyl transferase-like domain of the CHIKV nonstructural protein 2 (nsP2) increased MHC-I cell surface expression and antigen presentation efficiency by CHIKV-infected cells. Moreover, expression of WT nsP2 alone, but not nsP2 with mutations in the methyltransferase-like domain, resulted in decreased MHC-I antigen presentation efficiency. MHC-I surface expression and antigen presentation could be rescued by replacing VENUS-SIINFEKL with SIINFEKL tethered to beta2-microglobulin in the CHIKV genome, which bypasses the need for peptide processing and TAP-mediated peptide transport into the endoplasmic reticulum. Collectively, this work suggests that CHIKV escape the surveillance of antiviral CD8+ T cells, in part, by nsP2-mediated disruption of MHC-I antigen presentation. ### Competing Interest Statement The authors have declared no competing interest.

VLA1553 is a live-attenuated vaccine candidate for active immunisation and prevention of disease caused by chikungunya virus. We report safety and immunogenicity data up to day 180 after vaccination w...