An outbreak of atypical hand, foot and mouth disease associated Coxsackievirus A6 in children from Cape Verde, 2023.

Background: Rash is a common childhood infection, mainly caused by viruses. Hand, foot, and mouth disease (HFMD), a common viral rash infection, has become one of the most common infectious diseases in Asian countries and caused outbreaks in children and adults worldwide. Following the introduction of enterovirus A71 (EVA71) vaccines, Coxsackievirus A6 (CVA6) has recently emerged. However, the disease is not commonly reported in Africa, where studies are scarce.

Methods: In the current study, we focused on the HFMD outbreak that occurred in Cape Verde in July 2023 during field investigations around a cluster of patients with rash and fever. Samples collected from patients were tested using Measles and Rubella-specific immunoglobulin M and quantitative reverse transcription PCR (qRT-PCR) of a panel of viruses causing rashes and subjected to genome sequencing followed by phylogenetic analysis.

Results: Eighteen out of the 22 samples were tested positive for CVA6 RNA by real-time RT-PCR, of which two tested also positive for EVA71 and Coxsackievirus A16 (CVA16). Subsequent sequencing revealed that all CVA6 sequences belonged to the D genotype, particularly the D3 sub-genotype recently described in China.

Conclusion: Our study uncovers the first-ever reported outbreak of CVA6 associated with atypical HFMD in children from Cape Verde and highlights thus the need to implement an active hospital-based HFMD surveillance in Africa.