The Truth About Whooping Cough
Whooping cough, or Pertussis, is extremely contagious and very prevalent in the community, especially among adults. Some studies have shown that 30% of adults with a cough that lasts more than 3 weeks are coughing as a result of Pertussis infection. Before a vaccine against Pertussis was developed, there were over 200,000 cases per year.
Since the development of a vaccine against Whooping Cough, the incidence fell dramatically to an all-time low of 1,100 cases in 1976. However, with the emergence of anti-vaccine popularity, the number of cases has started to climb. In 2005, there were about 25,000 cases reported and in 2011, there were almost 10,000 cases in California alone, which resulted in 10 infant deaths.
Pertussis is very dangerous in infants with more than 50% of infected babies under the age of one requiring hospitalization. Of those hospitalized, 1% will die from the effects of Whooping Cough. Infants that are at the highest risk are those under three months of age, and account for 80% of all infants hospitalized.
Phases of Pertussis
In the first couple weeks of the infection, the symptoms are very similar to those of an upper respiratory infection which include mild fever, cough and runny nose. During this time, the patient is very contagious and usually has been to work, school, or daycare and probably a health care facility. Because signs of Pertussis are subtle, community outbreaks can occur frequently.
The next stage of the infection, is when the classic “whoop” develops (in infants under six months, the “whoop” is not common). Coughing fits can occur several times an hour and are very exhausting and can interfere with sleep and nutritional intake. This stage usually lasts about a month.
The last stage of the infection is where the coughing becomes less severe; this lasts a few weeks to a couple months.
Quick Diagnosis is Key
Given the significant infectious nature of Pertussis, and the severe complications that it can have on the community, rapid diagnosis is very important in preventing the spread. Currently, the use of PCR testing from swabs of the nasopharynx (swabs inserted deep into the nasal cavity) is the ideal method given the speed and accuracy deep into the illness (up to 4 weeks after onset of cough and even after antibiotic use). Also, clinical diagnosis is important in identifying possible cases so that these individuals can be advised to stay home until treatment is complete or testing is negative to prevent the further spread of infection.
Treatment of Whooping Cough is truly centered on decreasing the spread of illness. Unfortunately, unless detected and treated during the initial stage of the infection, the coughing phase of Pertussis is usually not shortened by much, if at all. Antibiotic treatment is effective for children and identifying possible exposed individuals is extremely important since preventive treatment of close contacts within 21 days of exposure is very effective, regardless of vaccination status.
Persons diagnosed with Whooping Cough need to be excluded from daycare, school, or work for five days of treatment. Untreated individuals will need to be excluded from these settings until 21 days have passed from the onset of a cough.
Preventing Whooping Cough
As is the case with most diseases, prevention is the best medicine and vaccination is very effective in preventing the spread of illness. Even if vaccination doesn’t prevent Pertussis, the severity and duration can be lessened. The infant/child vaccine that prevents Pertussis, DTaP, is given at two, four and six months of age as the initial series. This series is very important because it prepares the immune system to be ready to fight off infection if exposed.
A booster shot at 15-18 months reestablishes the necessary level of immunity for the child, and a second booster of DTaP is given between four and six years of age (known as kindergarten shots). Since our immune system is not perfect, it requires another booster, called Tdap, after 11 years (preferably before 12 years). It is recommended that all adults, including those over the age of 65, who have not been previously immunized with Tdap, be vaccinated.
Also, in the effort to reduce exposure and infection in infants, it is recommended that ALL pregnant women receive a Tdap vaccination after 20 weeks gestation regardless of prior vaccination.