Most cases of influenza in young children are undiagnosed. In three counties of Tennessee, New York state, and Ohio virological surveillance of children aged less than 5 years who presented with fever or acute respiratory infection was performed in 2000–2004. This was before the introduction of routine influenza vaccination for children aged 6–23 months (

) . A clinical diagnosis of influenza had been made for only 17% of outpatients and 28% of inpatients who had influenza virus infection demonstrated by viral culture or PCR assay on nose and throat swabs. Each year just under one in 1000 children were admitted to hospital with influenza but many more attended clinics or emergency departments. Failure to diagnose these infections may be a missed opportunity to prevent spread by use of antiviral medication.

Nitazoxanide is a thiazolide drug that has anti-infective properties against a very wide range of enteric pathogens including Cryptosporidium parvum, Cryptosporidium spp, Clostridium difficile, Giardia lamblia, Entamoeba histolytica, Blastocytisis hominis, Ascaris lumbricoides, Trichuris trichuria, Hymenolepsis nana, Taenia saginata, Fasciola hepatica, hepatitis B and C viruses, and rotavirus. Its mode of action is unknown. A study in Cairo (

) has shown that it may be useful in the treatment of severe rotavirus diarrhoea. Thirty-eight children (median age …