What is pertussis (whooping cough)?
Pertussis is a contagious bacterial disease that affects the respiratory tract.

Who gets pertussis?
Pertussis can infect persons of all ages, but is most serious in infants and young
children.

How is pertussis spread?
The bacteria are spread by contact with the respiratory droplets from an infected
person through coughing. Exposure usually occurs after repeated indoor face-to face
contact. Household spread is common.

What are the signs and symptoms of Pertussis?
In infants and young children, the disease begins much like a cold with a runny
nose, possible low grade fever and a mild but irritating cough for 1-2 weeks. The illness
progresses to spells of explosive coughing that can interrupt breathing, eating and
sleeping and is commonly followed by vomiting and exhaustion. Following the cough,
the patients may make a loud crowing or "whooping" sound as they struggle to inhale
air (hence the common name "whooping cough"). The severe coughing spells can last
for several weeks to two months or longer. In older children, adolescents and adults the
symptoms are usually milder and without the typical whoop.

What are the complications associated with pertussis?
In infants less than 6 months of age, the most common complication is bacterial
pneumonia (17%) followed by neurologic complications such as seizures (2.1%) and
encephalopathy (0.2 %). Loss of weight from nutritional disturbance and dehydration is
also a complication from the disease. More than half of the infants with confirmed
pertussis require hospitalization.

How soon do symptoms appear after exposure?
Usually 7-20 days.

When and for how long is a person able to spread pertussis?
Pertussis is most contagious in the early stage of the illness before the onset of
the explosive coughing spell. The spread of pertussis may be up to three weeks after
onset of the cold-like symptoms or up to three weeks after the onset of the explosive
coughing spells. The spread period can be reduced to 5 days after the initiation of a
14-day course of appropriate antibiotic therapy administered in the early stages of illness.

Is there treatment for pertussis?
There are three antibiotics recommended for the treatment of pertussis that will
shorten the period of communicability. A 14-day course of erythromycin,
trimethoprim/Sulfamethoxozale (TMP/SMX) or clarithromycin is recommended.
Persons with pertussis should be isolated until they have received at least 5 days
of a minimum 14-day course of antibiotics. They do not require isolation for the
last 9 days of antibiotic treatment.

How can the spread of pertussis be prevented?
Treatment is recommended for well persons who are close contacts (especially
household contacts) of the case to prevent or reduce the severity of illness. Any
untreated contacts of a case that develop a persistent cough should be tested for
pertussis. Confirmed or suspected cases of pertussis that do not receive appropriate
antibiotics should be isolated for 3 weeks.

How is pertussis confirmed?
Confirmation is by laboratory culture of a nasal swab obtained during the early
stage of illness.

How can pertussis be prevented?
Routine immunization of infants and children with acellular Pertussis (aP) vaccine
is recommended at 2, 4, 6 and 15-18 months of age with a booster dose at 4-6 years of
age. It is given in a combination with Diphtheria and Tetanus vaccines called DTaP. The
effectiveness of the vaccine in children who have received at least 3 doses is estimated
to be 80%; and protection is even greater against severe disease. Protection will begin
to diminish after about 3 years. Persons who experience pertussis after immunization
usually have a milder case. DTaP vaccine is currently recommended for children
2 months through 6 years of age. The current Pertussis vaccine should not be
administered to anyone 7 years of age or older because vaccine reactions are more
frequent. A safe and effective acellular pertussis vaccine for adolescents and adults is
under development but not yet available.

Does past infection with pertussis make a person immune?
Confirmed pertussis is likely to confer immunity. However, the duration of
immunity from past infection is unknown.