Pertussis vaccine contain reduced amounts of pertussis antigens compared to DTaP vaccines. Pearl Kendrick and Grace Eldering studied pertussis in the 1930s. They developed and ran the first large scale study of a successful vaccine for the disease. During the 1970s and 1980s, a controversy erupted related to the question of whether the whole-cell pertussis component caused permanent brain injury in rare cases, called pertussis vaccine encephalopathy. Despite this allegation, doctors recommended the vaccine due to the overwhelming public health benefit, because the claimed rate was very low (one case per 310,000 immunizations, or about 50 cases out of the 15 million
White line disease White line disease White line disease (also known as seedy toe) is a fungal infection of the horse's hoof. As the name suggests, it attacks the white line, which connects the sole to the hoof wall. It is sometimes mistaken for hoof wall separation disease, but is not to be confused because it is not genetic nor as severe. White line disease changes the typical light color of the white line to a black or dark gray color. It may also give off a foul odor. Lameness is often not present unless the disease is advanced. The disease may locate