Pertussis: What nurses need to know

Submitted by ADonahue on
Graphic illustration of lungs, person coughing

What is pertussis?

Pertussis, also known as whooping cough, is a respiratory illness caused by the highly contagious bacterium, Bordetella pertussi. Pertussis can cause severe disease, especially in infants younger than one year. Individuals that are immunocompromised or have asthma also have a higher risk of severe illness if infected. Pertussis primarily affects infants that are too young to receive the vaccine as well as older children and adults whose protection from the vaccine has waned.

What are the symptoms and complications of pertussis?

In the first one to two weeks, infected individuals may have symptoms like the common cold, including:

  • Runny or stuffed-up nose
  • Low-grade fever (less than 100.4°F)
  • Mild, occasional cough

As the illness progresses, thick mucus can start to accumulate in the airways, causing intense coughing fits known as paroxysms. Coughing fits can last for up to 10 weeks and feature a high-pitched “whoop” sound. Other symptoms of progression include:

  • Vomiting
  • Extreme tiredness
  • Difficulty sleeping
  • Struggling to breathe
  • Fractured rib(s) 

Individuals with a milder illness may not make the “whoop” sound and instead have an ongoing, hacking cough.

Many young infants do not cough at all. Infants may:

  • Gag or struggle to breathe
  • Have life-threatening pauses in breathing called apnea
  • Skin, lips, and/or nails turn blue or purple (caused by the lack of oxygen in the blood)

Pertussis can lead to serious complications, especially in infants, including pneumonia, seizures caused by lack of oxygen, brain damage, and even death. Older children and adults can experience other complications as well, including rib fractures, urinary incontinence, weight loss, hernias, and more.

How is pertussis transmitted?

Pertussis is transmitted through respiratory emissions that can be inhaled or deposited directly on a person’s mucous membranes. While pertussis has traditionally been considered a droplet-transmitted pathogen, scientific research indicates that pertussis can be transmitted through infectious aerosols. Experimental evidence on airborne transmission of pertussis was first published in a 2012 study, in which 100% of exposed baboons housed seven feet away from directly inoculated baboons became infected. Pertussis has also been detected in hospital air over 13 feet away from the patient’s bedside. 

The incubation period usually occurs between seven to 10 days from exposure to symptom onset but can range from four to 21 days. The infectious period for pertussis can last up to several weeks, typically beginning at the start of symptoms and lasting for at least two weeks after coughing begins. Some sources specify that pertussis is most contagious at three weeks and can be contagious for four to five weeks after illness onset.

Asymptomatic individuals can also transmit pertussis, as highlighted in recent scientific literature:

  • A systematic review examining 26 studies identified evidence suggestive of asymptomatic transmission and found that approximately 55 percent of those tested were asymptomatic.
  • A study investigating pertussis in infants and their mothers discovered that approximately 70 percent of infected mothers and 25 percent of infected babies displayed no symptoms.
  • New research also found that the acellular pertussis (aP) vaccine, which has been adopted in the U.S. since 1996, is effective in preventing severe disease but can be unsuccessful in preventing subclinical infections. This results in a large population of vaccinated people that can develop asymptomatic infections and unknowingly spread the bacteria to more vulnerable populations, like unvaccinated or high-risk individuals.

Who needs the pertussis vaccine?

There are two vaccines to protect against pertussis (as well as diphtheria and tetanus) available in the U.S.: DTaP and Tdap. Children younger than seven years old receive DTaP, while older children and adults receive Tdap. Tdap has a lower dose of diphtheria and pertussis antigens and acts as a booster for older children, adolescents, adults, and pregnant women.

The CDC’s childhood vaccination schedule has recommended the following since 2005 when Tdap was introduced (with Tdap during pregnancy being approved in 2012):

  • 5-dose DTaP series for infants and children younger than seven.
  • Routine Tdap vaccination for all adolescents with a single dose of Tdap at 11 to 12 years of age.
  • Single dose of Tdap during every pregnancy (preferably during the early part of gestational weeks 27 through 36).
  • Single dose of Tdap for adults who've never received Tdap.
  • Revaccination of healthcare personnel with Tdap may be considered when there's documented or suspected healthcare-associated transmission of pertussis.

What protections do nurses and other health care workers need when caring for a patient with suspected or confirmed pertussis?

Health care employers are responsible for providing a safe work and patient care environment. Multilayered infection prevention measures based on the scientific evidence and the precautionary principle should be implemented in all health care facilities, including:

  • Patient and visitor screening – Screen patients and visitors before or immediately upon arrival at the facility to ensure prompt identification and diagnosis.
  • Isolation and source control – Given the clear evidence that pertussis can be transmitted through the air even at long distances, it is most protective for patients with suspected or confirmed pertussis to be isolated in an airborne infection isolation room (AIIR). If an infection is confirmed and treatment is administered, patients should be isolated for 5 days. If treatment is not administered, patients should remain isolated for at least 3 weeks after cough onset.
  • Ventilation – Adequate ventilation is also essential for reducing the risk of transmission of respiratory infections in lobbies, waiting rooms, exam rooms, treatment areas, and other areas of the facility where a suspected or confirmed case could be present before being identified and isolated. Scientific evidence, as discussed above, demonstrates a large proportion of people infected with pertussis may be asymptomatic and emphasizes the need for ventilation.
  • Personal protective equipment – Given the clear evidence that pertussis can be transmitted through the air even at long distances, a respirator would be most protective for health care worker entering an area where a suspected or confirmed pertussis patient has been isolated, regardless of the staff’s immunity status. Powered air-purifying respirators (PAPRs) provide a higher level and more reliable protection than N95 filtering facepiece respirators. All respirators used must be NIOSH-approved and fit-tested (if applicable).
  • Pertussis vaccination – Health care workers, especially those that work with infants, could consider receiving a booster of the Tdap vaccine when there is documented or suspected nosocomial transmission of pertussis. Health care employers should make Tdap vaccines available free of charge to health care workers at risk of occupational exposure to pertussis.
  • Treatment – Clinical treatment of both symptomatic and asymptomatic persons, such as the administration of post-exposure prophylaxis, has been documented to prevent onward transmission and control outbreaks.
  • Exposure notification and contact tracing – Employers should conduct contact tracing and immediately notify staff who were potentially exposed. Exposure should include both direct contact while providing care and sharing air space (e.g., being in the same waiting room, triage station, etc.). Employers should also provide access to post-exposure prophylaxis, vaccination, or other appropriate follow-up measures as determined by a licensed health care provider at no cost to employees.
  • Paid precautionary medical removal – Employers should provide paid precautionary medical removal for any nurse or other health care worker who is removed from the workplace due to occupational exposure or infection with pertussis. Exposed health care personnel should be removed from work until completion of 5 days of treatment.