â¢ Contact. About Coxsackie A. The most well known Coxsackie A disease is Hand, foot and mouth disease (unrelated to foot and mouth disease), a common childhood illness which affects mostly children aged 10 or under,[1] often produced by Coxsackie A16.In most cases infection is asymptomatic or causes only mild symptoms. Contact. About Coxsackie A. The most well known Coxsackie A disease is Hand, foot and mouth disease (unrelated to foot and mouth disease), a common childhood illness which affects mostly children aged 10 or under,[1] often produced by Coxsackie A16.