More than 50 cases of whooping cough are being reported each day and 13 infants have died in the worst UK outbreak for more than 20 years.
There were 1,614 cases recorded in October, bringing the total so far this year to 7,728 compared with 797 during the same period four years ago. The total number of cases is tenfold higher than during the last peak in 2008.
The Health Protection Agency announced in September that all pregnant women would be offered a vaccination against whooping cough to stem the infant death toll, which had then claimed 10 lives. Three more infants died of the disease in October.