The Czech health authorities have warned of a heightened number of hepatitis A cases across the country. In the first seven months of this year the Health Ministry registered 130 patients with the disease, which is more than they had in the whole of 2007. Sixty-two hepatitis A cases were reported in the month of July alone. The illness is spreading mainly among drug addicts and the homeless and the majority of cases reported are in Prague, where the public has been warned not to underestimate the risk of infection. Vaccination of high risk groups is currently underway, but experts say it will be a while before the effects of that are felt.