Introduction

Pertussis (whooping cough) and asthma are two respiratory conditions often confused due to their similar symptoms, however, they are different in their health impact. Pertussis, commonly known as whooping cough, is a bacterial infection,  characterised by severe coughing fits in infants and young children.¹ Asthma is a chronic inflammatory airway condition with symptoms such as recurring wheezing, breathlessness, and coughing.² Pertussis and asthma can influence each other, with pertussis exacerbating asthma symptoms and asthma worsening the severity of pertussis infections. This article will explore each condition separately and how they can interact with each other. It will also focus on diagnosis and treatments for both. 

Pertussis

Pertussis, commonly known as whooping cough, is a contagious respiratory illness caused by the Bordetella pertussis bacteria.³ It spreads through respiratory droplets when an infected person coughs or sneezes. Pertussis can affect anyone, regardless of age, but it is particularly dangerous in infants and young children who are not fully vaccinated. It has an incubation period of 7-10 days.³ 

Symptoms^1,3

• Severe, prolonged coughing fits, often followed by a high-pitched "whooping" sound when inhaling
• Runny nose
• Sneezing
• Mild fever
• Fatigue

Pertussis progresses through three stages

1. Catarrhal Stage: Symptoms resemble those of a common cold, making early diagnosis difficult
2. Paroxysmal Stage: Intense, prolonged coughing fits begin, which can last for weeks and lead to fatigue and difficulty breathing
3. Convalescent Stage: Symptoms gradually improve, but the cough may linger for months, especially at night⁴

Diagnosis and treatment

Pertussis is diagnosed using a combination of methods, such as symptom evaluation, considering your medical history, and taking samples from the throat for laboratory testing.⁵ 

Treatment usually involves taking antibiotics such as azithromycin or erythromycin^5,6 to shorten how long you experience symptoms and prevent transmission. Starting the treatment as early as possible can speed up the total recovery time, and r prevents complications in infants and young children. Additionally, staying hydrated, getting plenty of rest, and using a humidifier can help to manage symptoms.^5,6

Understanding asthma

Asthma is a chronic respiratory condition that affects the airways in the lungs, causing them to narrow and become inflamed, which makes it difficult to breathe.² This makes it difficult for air to flow in and out of the lungs.⁸ When this happens, an episode of wheezing, coughing, and difficulty breathing can occur, which is known as an asthma attack.⁸ Asthma often starts in childhood but can develop at any stage. 

There are several types of asthma.^8,9 

• Allergic asthma: Triggered by allergens such as pollen, pet dander, and dust mites.
• Non-allergic asthma: Triggered by respiratory infections or cold air
• Exercise-induced asthma: Triggered by physical activity
• Occupational asthma: Triggered by workplace allergens or irritants

Symptoms^2,8,9

The inflammation and narrowing of the airways leads to symptoms such as:

• Wheezing
• Persistent coughing
• Chest tightness
• Shortness of breath
• Fatigue
• Excessive mucus

Diagnosis and treatment

Asthma is diagnosed by looking at your medical history, conducting a physical examination, and diagnostic tests such as spirometry.⁹ If you have a history of coughing, wheezing, chest tightness, or shortness of breath, this may indicate asthma. Additionally, having a family history of asthma or allergies and being exposed to asthma triggers like allergens and irritants can make it more likely for you to have asthma. They can also conduct a pulmonary function test that measures how well your lungs work and to see if there are any signs of airway obstruction. This is usually done with spirometry, which measures how much air you can forcefully exhale. 

Managing asthma typically involves a combination of medications to control symptoms, reduce inflammation, and avoid triggers. Medicines for asthma are categorised into quick-relief medications and long-term control medications.¹⁰ Quick-relief medications provide rapid relief for asthma symptoms and are designed to be used on an as-needed basis to help alleviate any symptoms of asthma attacks. These work by quickly opening up your airways to help you improve breathing. Some common quick-relief drugs are short-acting beta-agonists like albuterol and levalbuterol, which generally come in inhaler form.¹⁰ Long-term control medications are used to manage your asthma symptoms and prevent asthma attacks. This is done by reducing airway inflammation and hyperreactivity over time. They are typically taken daily. Common long-term control medications include inhaled corticosteroids and long-acting beta-agonists.¹⁰ In addition to medications, making an asthma action plan with your healthcare provider to help avoid known triggers is an essential part of asthma management. 

The impact of pertussis and asthma on each other

While there appears to be a connection between pertussis and asthma, how they are connected is a complex process which is not yet completely understood.^11,12 There is some research to show that pertussis and other respiratory illnesses can lead to both the development and the worsening of asthma in some people.¹¹ In infants and children, pertussis can be a serious condition that can lead to pneumonia and seizures. Sometimes, the coughing can cause infants to temporarily stop breathing. These respiratory issues can sometimes lead to long-term breathing problems, one of which is asthma.¹¹ 

If individuals with asthma, pertussis can worsen their symptoms. This is because the infection can worsen the inflammation and airway narrowing in the lungs, which leads to more wheezing, coughing, and difficulty breathing.^11,12 Additionally, having asthma can also make it harder for the immune system to fight pertussis^11,12. 

Preventive measures and management

In order to prevent pertussis and reduce your risk of making your asthma worse, there are several key measures you can follow. 

Vaccination is the most effective way to prevent pertussis.¹³ The DTaP vaccine protects against diphtheria, tetanus, and pertussis. It is commonly administered to children over the course of several doses as an infant and into early childhood. There is also a booster vaccine the Tdap vaccine, which can be used for adolescents and adults from ages 11-64 years old.¹³ Ensuring that you and your loved ones have received their vaccinations can significantly reduce the risk of becoming infected with pertussis. 

As with any infection, practising good hygiene practices such as frequently washing your hands properly with soap and water after coughing, sneezing, or touching contaminated surfaces is a good preventative measure. Covering any coughs and sneezes with a tissue or your elbow can help prevent the spread of droplets that can contain the pertussis bacteria. 

Make sure to avoid any close contact with people who are sick, particularly if they have symptoms of respiratory illnesses. 

If you have asthma, you must manage your asthma properly to reduce your risk of having exacerbated symptoms after exposure to pertussis. Make sure that you are following your healthcare provider’s advice, including taking any asthma medication that you have been prescribed. Be sure to have routine appointments to check in with your healthcare provider about the status of your asthma.

Summary

While both pertussis and whopping cough share some similar symptoms, they have different impacts on health and require different approaches. Pertussis is a bacterial infection that can be treated with antibiotics, while asthma is a chronic lung condition that is managed by controlling inflammation in the lungs and by avoiding triggers. There is some evidence that pertussis can make asthma symptoms worse and that having asthma can make the effects of pertussis worse. Importantly, getting vaccinated against pertussis greatly reduces the chance of this occurring.