Introduction

Pertussis, commonly known as whooping cough, is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis. It is characterised by severe coughing spells that can last for weeks or even months, often leading to a distinctive “whooping” sound when the patient tries to breathe in. Although pertussis can affect individuals of any age, it is particularly concerning in school-age children, who are more susceptible to contracting and spreading the disease due to their close interactions in school settings. Understanding the prevalence of pertussis in this age group is crucial for public health strategies aimed at controlling outbreaks and preventing the disease.

Epidemiology of pertussis

Global prevalence

Pertussis remains a significant public health issue worldwide. According to the World Health Organisation (WHO), there are an estimated 24.1 million pertussis cases globally per year, resulting in approximately 160,000 deaths. While vaccination programmes have significantly reduced the incidence of pertussis, the disease persists in many regions, particularly in countries with low vaccination coverage.¹

Regional variations

The prevalence of pertussis varies considerably between regions. High-income countries like the United States and those in Western Europe have relatively low incidence rates due to widespread vaccination efforts. However, they still experience cyclical outbreaks every three to five years. In contrast, low- and middle-income countries often face higher rates of pertussis due to challenges in vaccination coverage and healthcare access.²

Focus on the united states

In the United States, pertussis cases have fluctuated over the years, with notable outbreaks occurring in 2012 and 2014.² Despite the availability of vaccines, pertussis remains endemic, with tens of thousands of cases reported annually. School-age children are particularly vulnerable during outbreaks, highlighting the need for targeted public health interventions.

Age distribution

While pertussis can affect all age groups, school-age children (5-18 years) account for a significant proportion of cases. According to the Centers for Disease Control and Prevention (CDC), children aged 7 to 10 years have the highest incidence rates among school-age groups. This is partly due to waning immunity from the childhood DTaP (diphtheria, tetanus, and acellular pertussis) vaccine series and incomplete vaccination schedules.²

Factors contributing to pertussis prevalence

Vaccination rates

Vaccination is the most effective way to prevent pertussis. The DTaP vaccine, which protects against diphtheria, tetanus, and pertussis, is routinely administered to infants and young children. Booster doses (Tdap) are recommended for older children and adults to maintain immunity.³ However, incomplete vaccination and delays in receiving booster shots contribute to pertussis outbreaks in school settings.

Vaccine efficacy and duration of immunity

While the pertussis vaccine is highly effective, its protection wanes over time. Studies show that immunity can decrease significantly five to ten years after the last vaccine dose.³ This waning immunity highlights the importance of booster vaccinations for older children and adults to maintain community-wide protection.

Public health policies

Effective public health policies are crucial in managing pertussis prevalence. National immunisation programs play a vital role in ensuring high vaccination coverage. School-entry vaccination requirements and public health campaigns can help improve vaccination rates and prevent outbreaks.³

Socioeconomic and environmental factors

Access to healthcare services and socioeconomic factors also influence pertussis prevalence. Populations with limited access to vaccination services or those living in crowded conditions are at higher risk for pertussis transmission. Additionally, schools and childcare settings can facilitate the spread of the disease due to close interactions among children.

Recent trends and outbreaks

Historical trends

Pertussis has experienced cyclical outbreaks for decades, with peaks every three to five years. These cycles are attributed to waning immunity and fluctuations in vaccination coverage. The introduction of acellular pertussis vaccines in the 1990s initially led to a decline in cases, but recent increases highlight the need for ongoing surveillance and booster vaccinations.³

Recent outbreaks

Recent outbreaks have underscored the challenges in controlling pertussis. For example, a 2012 outbreak in Washington State resulted in over 4,800 cases, emphasising the importance of booster vaccinations and timely immunisation.⁴ Factors contributing to recent increases include under-vaccination, vaccine refusal, and the disease’s cyclical nature.

Impact on school-age children

Health consequences

Pertussis can have severe health consequences for school-age children. In addition to the intense coughing fits, complications such as pneumonia, weight loss, and even rib fractures can occur. The prolonged duration of symptoms can lead to missed school days and hinder academic performance.

Economic and social impacts

The economic burden of pertussis is substantial, affecting families and healthcare systems. Medical expenses, lost productivity, and the need for public health interventions contribute to the overall cost.⁴ Socially, pertussis outbreaks can lead to stigma and anxiety within communities, particularly in school settings.

Strategies for prevention and control

Improving vaccination coverage

Increasing vaccination rates is essential for preventing pertussis outbreaks. Strategies include:

• Ensuring timely vaccination schedules for infants and children
• Implementing school-based vaccination programs
• Promoting public awareness campaigns to educate parents and caregivers⁶

Monitoring and surveillance

Effective surveillance systems are critical for early detection and response to pertussis outbreaks. Data collected from these systems can guide public health interventions and policy decisions. Healthcare providers play a key role in reporting cases and ensuring timely diagnosis and treatment.⁷

Research and development

Advancements in pertussis vaccine research are ongoing, with efforts focused on improving vaccine efficacy and duration of immunity. Innovations in diagnostic methods and treatment options also contribute to better disease management and control.

Summary

Pertussis remains a significant public health concern, particularly for school-age children. Despite the availability of vaccines, the disease persists due to factors such as waning immunity and vaccination coverage challenges. Recent outbreaks highlight the importance of ongoing surveillance, public health policies, and research efforts to prevent and control pertussis. Increasing vaccination coverage, improving surveillance systems, and advancing vaccine research are essential strategies for reducing the prevalence of pertussis and protecting vulnerable populations.

FAQs

Why is pertussis more common in school-age children?

School-age children are more susceptible to pertussis due to their close interactions with peers in school settings, waning immunity from earlier vaccinations, and incomplete vaccination schedules.

How effective is the pertussis vaccine?

The pertussis vaccine is highly effective but its immunity wanes over time, typically requiring booster doses every five to ten years to maintain protection⁸.

What are the symptoms of pertussis?

Pertussis symptoms include severe coughing fits, a distinctive “whooping” sound during inhalation, vomiting after coughing, and exhaustion.

How can we prevent pertussis outbreaks in schools?

Preventing pertussis outbreaks in schools involves ensuring high vaccination coverage, promoting timely booster doses, implementing school-based vaccination programs, and maintaining effective surveillance systems.