Repeating vaccination promotes whooping cough resistance. This is evidenced by the PhD research conducted by Pauline Versteegen. She researched post-vaccination immunity to whooping cough in age groups from 7 to 70 years. On Tuesday 28 May, she was awarded her doctoral degree at Utrecht University.

Whooping cough is a very contagious disease that is currently circulating in the Netherlands. The disease is particularly dangerous to young, unvaccinated children. People over 60 can also become seriously ill from the disease. The whooping cough vaccine has been in the National Immunisation Programme since 1957. There has been a dramatic decrease in young children with whooping cough as a result. Despite that, whooping cough has become more common again in recent years.

Slowly waning protection

Pauline Versteegen: “The protection offered by the current whooping cough vaccination wanes after a number of years. As a result, people gradually become less well protected against an infection with whooping cough bacteria. Since whooping cough is more common again, I wanted to research the effect of an additional repeat vaccination.”

Difference between age groups

To that end, Versteegen investigated antibody development and immune memory to determine immunity among children and adults. All the age groups addressed in the study responded well to the repeat vaccination. However, this repeat vaccination is not equally helpful for everyone. If older school children and teens were already vaccinated against whooping cough in early childhood, their symptoms will be reasonably mild if they are infected. A repeat vaccination does not seem necessary for these groups. Among adults aged 50 years and older and people in certain risk groups with underlying health conditions, whooping cough is more likely to cause complications. For these people, a repeat vaccination against whooping cough may be helpful.

Comparative research

Versteegen conducted her research at the Centre for Immunology of Infectious Diseases and Vaccines, within the RIVM Centre for Infectious Disease Control. She tested blood samples from participants aged 7 to 90 years old from the PIENTER 3 population screening in the Netherlands in 2016/17. She compared these results to studies from 1995/96 and 2006/2007.

Teens show main increase in whooping cough infections

In all age groups, she saw an increase in the number of people who had recently had a whooping cough infection. That increase was strongest among teenagers. She also saw a clear increase in the number of people who had very recently had a whooping cough infection among children of primary school age and among adults aged 50-64 years.

More whooping cough infections than reported

The blood sample research showed that 5.9% of people aged 7–90 years had recently had a whooping cough infection. That percentage is higher than the reported number of whooping cough cases in the Netherlands. Among adults aged 50 years and older, the blood sample research showed that far more people had had a whooping cough infection that had been indicated by the reported case numbers.

PhD degree and dissertation

Pauline Versteegen was awarded her doctoral degree at Utrecht University on Tuesday 28 May. Her dissertation on “Antibody responses and B cell immunity after pertussis booster vaccination: immunity in young and old in times of endemic pertussis” can be accessed online: Publicatie Online: Pauline Versteegen.