Syndromic detectability of haemorrhagic fever outbreaks

Emma E Glennon; Freya L Jephcott; Alexandra Oti; Colin J Carlson; Fausto A Bustos Carillo; C Reed Hranac; Edyth Parker; James L N Wood; Olivier Restif

(which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.03.28.20019463 doi: medRxiv preprint syndromes, we estimate the detectable sizes of each syndrome as well as likely 199 misidentifications between syndromes (Fig. 2) . We estimate, for example, that Ebola virus 200 disease and Marburg virus disease (MVD) are most likely to be misidentified as dengue 201 haemorrhagic fever, yellow fever, or typhoid fever. The clinical features caused by EVD and 202 MVD outbreaks are more likely to be caused by other diseases until at least 6 and 7 cases 203 occur, respectively. Before this detectability threshold, the balance of probabilities suggests a 204 few cases of more common aetiologies are presenting with rare clinical features; after this 205 threshold, the presentation of cases is unusual enough to suggest a common presentation of 206 extremely rare aetiologies (i.e., filoviral disease). We summarise the estimated 207 detectabilities-i.e., probabilities of correct aetiological identification-for each syndrome in 208 with malaria at small cluster sizes (approx. 1-5 cases) and dengue haemorrhagic fever at 214 larger sizes (approx. 5+ cases) and is not 50% detectable until a cluster size of 25 cases. 215