Pertussis
, also called whooping cough, is a highly contagious bacterial infection of the lining and airways of the respiratory tract. It is caused by the bacterium,
Bordetella pertussis
.
Pertussis is spread by inhaling wet droplets from the sneeze or cough of a person infected with pertussis or by having direct contact with the person’s respiratory secretions.
This infection is most common in infants and children. People at most risk are those who:
- Have not been immunized
- Live or work with someone who has pertussis
- Live in close quarters (eg, dormitory, nursing home)
- Live in crowded or unsanitary conditions
- Are pregnant
In 2003, more than 11,000 cases of pertussis were reported in the US, most of which (40%) were adolescents ages 10-19 years old. Most of the deaths due to pertussis occur in infants.
Symptoms include:
- Runny nose and congestion
- Sneezing
- Watery, red eyes
- Dry cough
- Severe coughing spells than may end with a noisy inhale, or "whoop" (this may not be heard in young infants)
- Vomiting
Symptoms usually begin within 3-12 days following exposure. Cold-like symptoms can last for up to two weeks, followed by a dry, hacking cough that progresses to severe coughing spells. The average duration of the illness is six weeks, but can range from three weeks to three months. In severe cases, seizures, periods of apnea,
pneumonia
, collapsed lungs,
abdominal and inguinal hernias
,
encephalitis
, and death may occur.
Once pertussis is confirmed by bacterial cultures, patients are treated with antibiotics. To help reduce vomiting and chances of dehydration, patients may be advised to eat small, frequent meals and drink plenty of water, fruit juices, and clear soup. Infants who are diagnosed with pertussis may be hospitalized.
The pertussis vaccine contains small, purified pieces of the pertussis germ. It is not available as a single vaccine; it is given in combination with
diphtheria
and
tetanus
vaccines. It is given as an injection, usually into the arm or thigh. It must be stored in a refrigerator prior to administration.
The DTaP vaccine, which protects against diphtheria, tetanus, and pertussis, can be given to children younger than seven years old. It is generally required before starting school and is given in a five-dose series at ages two, four, six, and 15-18 months, followed by a booster that is given between the ages of 4-6. The Food and Drug Administration (FDA) has recently approved new booster vaccines against pertussis (also in combination with tetanus and diphtheria) for adolescents and adults. These vaccines are referred to as Tdap; one dose is recommended for adolescents ages 11-18 years and one dose for adults ages 19-64 years.
Adolescents who have already gotten a booster dose of Td (tetanus-diphtheria) are encouraged to get a dose of Tdap as well, but with a waiting period of at least five years between Td and Tdap.
It is recommended that adults who expect to have close contact with an infant younger than 12 months get a dose of Tdap, with an encouraged, but not required, waiting time of two years since the last dose of Td. Also, healthcare workers who have direct patient contact with hospitals or clinics should get a dose of Tdap, with a recommended two-year waiting period since the last dose of Td. Finally, new mothers who have never received a dose of Tdap should get a dose as soon as possible after delivery.
Most people tolerate the pertussis-containing vaccines without any trouble. The most common side effects are:
- Pain, redness, or swelling at the injection site
- Mild fever
- Headache
- Tiredness
- Nausea
- Vomiting
- Diarrhea
- Stomach ache
A fever over 102º F, severe gastrointestinal problems, or severe headache may uncommonly occur. Nervous system problems or a severe allergic reaction are extremely rare. Anaphylaxis (life-threatening, widespread allergic reaction) is extremely rare.
The vast majority of people should receive their pertussis-containing vaccinations on schedule. However, individuals in whom the risks of vaccination outweigh the benefits include:
- People who have had a life-threatening allergic reaction to DTP, DTap, DT, Tdap, or Td vaccine
- People who have had a severe allergy to any component of the vaccine to be given
- People who have gone into a coma or long seizure within seven days after a dose of DTP or DTaP
If you have an allergy to latex, epilepsy, or other nervous system problem; severe swelling or severe pain after a previous dose of any component of the vaccination to be given; or
Guillain-Barre syndrome
, talk with your doctor before getting the vaccine.
Wait until you recover to get the vaccine if you have moderate or severe illness on the day your shot is scheduled.
Isolating those with any contagious disease has long been the main approach to preventing its spread. It is essential, for example, to keep people with pertussis at home until the illness has run its course.
People who have been in close contact with someone infected with pertussis may be advised to take preventive antibiotics.
In the event of a pertussis outbreak, all people who may have been exposed to pertussis should be brought up to date with the vaccination. This would include all those living in the same household as the infected person, as well as all those attending his or her childcare facility, school, college, or other institution.
It is important to protect infants from pertussis by isolating those who have the infection. Diagnosing the disease as quickly as possible can help control future outbreaks.
