Pertussis

Causes and Risks:

Pertussis, also known as whooping cough, is caused by infection with the Bordetella pertussis bacteria. The infection can affect all. Prior to immunization pertussis was confined mostly to infants and young children. Now that the majority of children are immunized before school age a higher percentage of cases are seen among adolescents and adults. About 38 percent to recognized cases occur in infants younger than six months. of age, stressing the need for early immunization (see childhood immunization schedule). There were 7,138 cases of whooping cough reported in the U.S. in 1996. The infection is spread through the air by respiratory droplets from an infected person. The incubation period is usually seven days.

The bacteria invade the nose and throat, the trachea, and the bronchial tubes of the lungs. The infection usually lasts six weeks. It starts with symptoms similar to the common cold , and progresses to spasms (paroxysms) of coughing after 10 to 12 days. The cough is characterized by repeated coughing, two or three coughs without inhaling then a characteristic inspiratory whoop. Typically, the face becomes more red with each cough then subtly bluish (cyanotic). The child may momentarily lose consciousness at the end of a coughing spell. During this stage there is heavy mucus production and coughing spells may induce vomiting . Pertussis should always be considered when vomiting is associated with coughing. In infants, choking spells are common.

Convalescence begins about four weeks after the onset of symptoms and may last several weeks. Paroxysms of coughing may recur over the next several months, usually due to irritation from an upper respiratory infection .

Immunization may modify the course of pertussis. When symptoms are not classical, pertussis is difficult to diagnose and as a result, the disorder is likely to be underdiagnosed. Several new studies have suggested that the possible diagnosis of pertussis should be entertained in any adult with an acute respiratory illness in which the cough persists for over two weeks.

Prevention:

DtaP vaccine or pertussis immunization (vaccine) starting in infancy protects children against this disease. During epidemics, health care providers or others at risk may be advised to receive a booster dose of the vaccine. During epidemics, unimmunized children under the age of seven should be excused from school and public gatherings for 14 days after the last reported exposure and isolated from anyone known or suspected to be infected. Cases of the disease are reported to public health officials by health care providers so that health warning announcements and other preventative measures can be taken. Pertussis is now recognized more often in adolescents and adults. Pertussis immunization is not 100 percent effective and slowly becomes less effective over the years. Individuals who have been immunized in the past may still develop infection but it is usually atypical or very mild. Therefore, during epidemics, adolescents in school, health care workers or other adults with high exposure risk should consider a booster immunization.

Symptoms:



Signs and Tests:
Tests may include:



Treatment:

Erythromycin, an antibiotic, is given and may shorten the duration of the symptoms somewhat. Infants under 18 months of age require constant supervision because breathing may temporarily stop during coughing spells. Infants with severe cases should be hospitalized. An oxygen tent with high humidity may be used. Intravenous fluid may be indicated if coughing spells are severe enough to prevent adequate oral (by mouth) fluid intake. Sedatives may be prescribed for young children. Cough mixtures or expectorants and cough suppressants are usually not helpful and should not be used.

Prognosis:

Untreated severe disease in infants has a poor prognosis (probable outcome). The disease has a one percent to 2 percent death rate. Death may occur from lack of oxygen to the brain (anoxic encephalopathy) and bronchopneumonia

Complications:



Call Your Healthcare Provider:

Call your health care provider if you or your child develops symptoms of pertussis.

Emergency symptoms include a bluish skin coloration indicating a lack of oxygen, periods of stopped breathing ( apnea ), seizures or convulsions , high fever , persistent vomiting , and dehydration .