Seroepidemiology and mathematical modelling of non-polio enteroviruses

Thesis

Enteroviruses are spread fecal–orally or via respiratory transmission and cause a wide range of diseases. They generally cause mild and self-limited illness but have emerged to cause outbreaks with more severe disease manifestations than previously known. The principal public health needs for enterovirus surveillance include outbreak detection, response and monitoring of enteroviruses associated with severe disease. However, the burden of enterovirus infections is not adequately described due to inadequate systemic surveillance. Here, serum neutralizing antibodies to EV-D68, EV-A71, CVA6 and EV-D111 were measured in samples collected in the UK and four African countries to estimate population-level exposure.

Overall, the serology data showed high antibody levels and seroprevalence that reached 100% in adults indicating extensive exposure and ubiquitous virus circulation. Clinical detection of enteroviruses in the UK showed biennial and annual occurrence of EV-A71 and CVA6, respectively. CVA6 detections were marked by an increasing trend from 2006 to 2017. Model fitting of the seroprevalence data showed possible existence of age-specific transmission or relative risk of infection. The increase in virus detection or clinical occurrence without parallel increase in FOI could be attributed to a change in virus characteristics or pathogenicity leading to pronounced clinical disease even without a change in virus transmissibility. This thesis demonstrates the application of serology and mathematical modelling to estimate pathogen prevalence. The data and inferences will be beneficial for guiding future policies focused on enterovirus epidemiology and disease burden. Certainly, better documentation of enterovirus true prevalence and collective impact on human health is warranted.

Authors: Kamau, E

• DOI: 10.5287/ora-nznpomgbr
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: UK; enteroviruses; seroepidemiology
• Subjects: Epidemiology; Virology