Catherine Hyams PhD thesis defined the role of the Streptococcus pneumoniae capsule on pneumococcal interactions with complement factors and phagocytes, demonstrating that resistance to complement mediated immunity is associated with capsular serotype, showing relatively invasive strains of pneumococcus are more resistant to complement-mediated immunity. ​​

She undertakes research examining trends in adult pneumonia, investigating the epidemiology of respiratory infection. and is particularly interested in how S. pneumoniae disease may be changing in response to COVID-19 and pneumococcal vaccination, as well as determining the consequences of acute viral and bacterial infection for patients and improving outcomes for these patients. ​

Catherine Hyams is the Principal Investigator for The Avon CAP study. This study seeks to determine the burden of adult acute respiratory disease and assess how the emergence of COVID-19 may lead to changes in adult respiratory disease.  By conducting comprehensive surveillance at both acute care NHS Trusts in Bristol, the study aims to estimate accurate incidence for acute lower respiratory tract disease and determine the effect the current and novel vaccination would impact patient morbidity and mortality. ​
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She leads a retrospective cohort study, assessing invasive pneumococcal disease in Bristol, UK. The study aims to determine if the clinical phenotype and epidemiology of Streptococcus pneumoniae is changing over time. ​
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She also leads a study examining patients hospitalised with exacerbations or respiratory deteriorations of idiopathic pulmonary fibrosis. The study aims to examine what factors affect patient outcomes.  ​