Long-awaited update on estimates of acute rheumatic fever in Africa
Authors: Mark E Engel
Journal: The Lancet Global Health (2021)

Despite being the only cardiovascular disease of global impact that has been proven to be completely preventable, rheumatic heart disease remains prevalent in low-income and middle-income countries,1Watkins DA Johnson CO Colquhoun SM et al.Global, regional, and national burden of rheumatic heart disease, 1990–2015.N Engl J Med. 2017; 377: 713-722Crossref PubMed Scopus (437) Google Scholar including those in Africa, where primary prevention programmes are not well established due to lack of available resources.2Excler JL Kim JH Accelerating the development of a group A Streptococcus vaccine: an urgent public health need.Clin Exp Vaccine Res. 2016; 5: 101-107Crossref PubMed Google Scholar An understanding of the epidemiology of rheumatic heart disease has been facilitated through the number of studies published over the past decade, including some on group A streptococcus, the preceding infection thought to initiate the cascade of events leading to permanent valve damage. Rheumatic heart disease prevalence has been increasing since 1990; an estimated 40·5 million people were affected in 2019.1Watkins DA Johnson CO Colquhoun SM et al.Global, regional, and national burden of rheumatic heart disease, 1990–2015.N Engl J Med. 2017; 377: 713-722Crossref PubMed Scopus (437) Google Scholar To advance empirically-supported care and improve outcomes for those with rheumatic heart disease, development of evidence regarding the epidemiology of its prequel, acute rheumatic fever, is important. Research-funding constraints have resulted in a noticeable lack of available data,3Watkins DA Zuhlke LJ Engel ME Mayosi BM Rheumatic fever: neglected again.Science. 2009; 324: 37Crossref PubMed Scopus (25) Google Scholar especially in resource-poor settings hampered by lack of equipment and dedicated research infrastructure. Thus, there remains a clear need for data from methodologically rigorous investigations, especially given the aged nature of existing acute rheumatic fever data from retrospective studies, often riddled with threats to both internal and external validity.4Talari K Goyal M Retrospective studies—utility and caveats.J R Coll Physicians Edinb. 2020; 50: 398-402Crossref PubMed Scopus (22) Google Scholar In The Lancet Global Health, Emmy Okello and colleagues5Okello E Ndagire E Muhamed B et al.Incidence of acute rheumatic fever in northern and western Uganda: a prospective, population-based study.Lancet Glob Health. 2021; (published Aug 19.)https://doi.org/10.1016/S2214-109X(21)00288-6Summary Full Text Full Text PDF PubMed Scopus (4) Google Scholar present the results of a thorough two-site population-based study of the incidence of acute rheumatic fever in an African setting. The primary outcome was to document incidence rates of definite acute rheumatic fever among children aged 5–14 years in two districts in Uganda. Their results, indicating estimated incidence rates of 25 cases (95% CI 13·7–30·3) per 100 000 person-years in Lira district (north) and 13 cases (7·1–21·0) per 100 000 person-years in Mbarara district (west), provide the first documentation of acute rheumatic fever incidence in sub-Saharan Africa. Although incidence was lower than expected, the authors point out the limitations of recruitment and missed cases and hypothesise that the true incidence might be as high as two to three times higher than the estimated value, especially given the high rheumatic fever burden. Nevertheless, these data, with an active case-finding component, have an advantage over hospital or clinic data, which only account for patients with access to care. Furthermore, the authors sought to provide a clinical profile of children presenting with definite and possible acute rheumatic fever. They document a high proportion of moderate to severe valvular involvement among cases, probably indicative of failed diagnoses of previous acute rheumatic fever episodes. These results serve to complement those of REMEDY,6Zuhlke L Karthikeyan G Engel ME et al.Clinical outcomes in 3343 children and adults with rheumatic heart disease from 14 low- and middle-income countries: two-year follow-up of the global rheumatic heart disease registry (the REMEDY Study).Circulation. 2016; 134: 1456-1466Crossref PubMed Scopus (129) Google Scholar which emphasised the dearth of acute rheumatic fever data in patients with rheumatic heart disease. This study is notable for several reasons. First, the authors confirm the use of community sensitisation and health worker education in increasing acute rheumatic fever awareness.7Okello E Ndagire E Atala J et al.Active case finding for rheumatic fever in an endemic country.J Am Heart Assoc. 2020; 9e016053Crossref PubMed Scopus (6) Google Scholar Second, it demonstrates that it is possible, with appropriate funding and planning, for studies of such a nature to be successfully undertaken in sub-Saharan Africa, despite the challenges of competing priorities. Finally, the data provide a valuable update on the estimation of acute rheumatic fever incidence, which is long overdue, making a case for further research investment especially towards the development of a simple biomarker for early detection and timely diagnosis of acute rheumatic fever. The authors are to be congratulated for this wonderful contribution to rheumatic heart disease research; we await further outcome data from this study. I declare no competing interests. Incidence of acute rheumatic fever in northern and western Uganda: a prospective, population-based studyTo the best of our knowledge, this is the first population-based study to estimate the incidence of acute rheumatic fever in sub-Saharan Africa. Given the known rheumatic heart disease burden, it is likely that only a proportion of children with acute rheumatic fever were diagnosed. These data dispel the long-held hypothesis that the condition does not exist in sub-Saharan Africa and compel investment in improving prevention, recognition, and diagnosis of acute rheumatic fever. Full-Text PDF Open Access