health

At one time whooping cough was a leading cause of death in infants
and toddlers, causing 3,000 to 5,000 deaths in the United States
every year. Even though vaccines against whooping cough have been
available since the 1940s, the disease is still one of the leading causes
of vaccine-preventable deaths worldwide. The World Health Organization
(WHO) estimates that there are between 30 and 50 million
cases of pertussis each year around the world, and 300,000 deaths.
Ninety percent of cases of whooping cough occur in the developing
world. Widespread vaccination against the disease, however, has
lowered the death rate in the United States to fewer than thirty cases
per year.
In the United States, cases of whooping cough tend to cluster in
cycles, with peaks every three to four years. Outbreaks of whooping
cough are seasonal, with most cases occurring between June and September.
On average there are about 2.7 cases of whooping cough per
100,000 in the general population in North America.
Most people who get whooping cough in the United States are
unimmunized children or older teenagers and adults whose full immunity
has faded. The classic symptoms of whooping cough are not often
seen in this latter group, who are likely to have cough for more than
three weeks. According to the Centers for Disease Control and Prevention
(CDC), 29 percent of patients with whooping cough are younger
than one year; 12 percent are aged one to four years; 10 percent are aged
five to nine years; 29 percent are aged ten to nineteen years; and 20 percent
are older than twenty years.
As far as is known, males and females are equally affected by the disease.
Caucasians appear to be more likely to get whooping cough than
either African Americans or Native Americans.