Dissecting recurrent waves of pertussis across the boroughs of London

Abstract

Pertussis has resurfaced in the UK, with incidence levels not seen since the 1980s. While the fundamental causes of this resurgence remain the subject of much conjecture, the study of historical patterns of pathogen diffusion can be illuminating. Here, we examined time series of pertussis incidence in the boroughs of Greater London from 1982 to 2013 to document the spatial epidemiology of this bacterial infection and to identify the potential drivers of its percolation. The incidence of pertussis over this period is characterized by 3 distinct stages: a period exhibiting declining trends with 4-year inter-epidemic cycles from 1982 to 1994, followed by a deep trough until 2006 and the subsequent resurgence. We observed systematic temporal trends in the age distribution of cases and the fade-out profile of pertussis coincident with increasing national vaccine coverage from 1982 to 1990. To quantify the hierarchy of epidemic phases across the boroughs of London, we used the Hilbert transform. We report a consistent pattern of spatial organization from 1982 to the early 1990s, with some boroughs consistently leading epidemic waves and others routinely lagging. To determine the potential drivers of these geographic patterns, a comprehensive parallel database of borough-specific features was compiled, comprising of demographic, movement and socio-economic factors that were used in statistical analyses to predict epidemic phase relationships among boroughs. Specifically, we used a combination of a feed-forward neural network (FFNN), and SHapley Additive exPlanations (SHAP) values to quantify the contribution of each covariate to model predictions. Our analyses identified a number of predictors of a borough’s historical epidemic phase, specifically the age composition of households, the number of agricultural and skilled manual workers, latitude, the population of public transport commuters and high-occupancy households. Univariate regression analysis of the 2012 epidemic identified the ratio of cumulative unvaccinated children to the total population and population of Pakistan-born population to have moderate positive and negative association, respectively, with the timing of epidemic. In addition to providing a comprehensive overview of contemporary pertussis transmission in a large metropolitan population, this study has identified the characteristics that determine the spatial spread of this bacterium across the boroughs of London.

Association between pertussis vaccination coverage and other sociodemographic factors and pertussis incidence using surveillance data

“…Low income has been associated with lower vaccine coverage and increased likelihood of disease risk in the US ( Hill et al, 2016 ; Larson et al, 2014 ). Household size and crowding have been identified as important factors contributing to pertussis transmission ( Magpantay and Rohani, 2015 ; Saeidpour et al, 2022 ). In large households, there is an increased possibility of prolonged close contact and transmission between an index cases and household members.…”

Understanding the impact of adult pertussis and current approaches to vaccination: A narrative review and expert panel recommendations

“…While some research has been undertaken on the transmission dynamics of pertussis using passive surveillance, 71 , 72 patterns of transmission in older adults are not currently understood. The panel noted that research in this area is required to determine any indirect effects of adult Tdap vaccination on interrupting transmission and establish the most effective timing for administering adult boosters.…”

Membrane-penetrating peptide from the translocation region ofBordetellaAdenylate Cyclase Toxin prevents toxin cytotoxicity on target cells

“…The introduction worldwide of the vaccine in the forties led to a large decrease in the number of cases [2,4]. However, epidemic peaks have continued being recorded every 4 to 5 years, leading the WHO to declare whooping cough re-emerging disease [4][5][6]. Consequently, whooping cough represents today one of the main causes of mortality due to vaccine-preventable diseases for the child population.…”