Chickenpox (varicella)

Chickenpox (varicella) is a highly contagious infection caused by the varicella-zoster virus, primarily affecting children. It typically presents with fever and a characteristic vesicular rash and is spread through respiratory droplets and direct contact with lesions. Although usually self-limiting, severe complications such as pneumonia, encephalitis and secondary bacterial infections can occur, particularly in adults, pregnant women, neonates and immunocompromised individuals. Management is mainly supportive, while antiviral prophylaxis is recommended for high-risk groups. The introduction of the measles, mumps, rubella and varicella vaccine into the UK immunisation programme in 2026 aims to reduce disease transmission, complications and hospitalisations.