Imported rickettsial infections to the United Kingdom, 2015-2020

Clare E Warrell; Jane Osborne; Laura Nabarro; Barry Gibney; Daniel P Carter; Jennifer Warner; Catherine F Houlihan; Timothy J G Brooks; Tommy Rampling

doi:10.1016/j.jinf.2023.03.015

Imported rickettsial infections to the United Kingdom, 2015-2020

J Infect. 2023 May;86(5):446-452. doi: 10.1016/j.jinf.2023.03.015. Epub 2023 Mar 21.

Authors

Clare E Warrell¹, Jane Osborne², Laura Nabarro³, Barry Gibney², Daniel P Carter², Jennifer Warner², Catherine F Houlihan⁴, Timothy J G Brooks², Tommy Rampling⁵

Affiliations

¹ Rare and Imported Pathogens Laboratory, Salisbury, UK; London School of Hygiene and Tropical Medicine, London, UK. Electronic address: clare.warrell@ukhsa.gov.uk.
² Rare and Imported Pathogens Laboratory, Salisbury, UK.
³ Hospital for Tropical Diseaess, London, UCLH, UK.
⁴ Rare and Imported Pathogens Laboratory, Salisbury, UK; Hospital for Tropical Diseaess, London, UCLH, UK; Department of Clinical Virology UCLH, UK; Infection and Immunity, University College London, UK.
⁵ Rare and Imported Pathogens Laboratory, Salisbury, UK; Hospital for Tropical Diseaess, London, UCLH, UK; Infection and Immunity, University College London, UK.

PMID: 36948252
DOI: 10.1016/j.jinf.2023.03.015

Abstract

Objective: The burden of imported rickettsial infection in the UK is not previously described. This retrospective review identifies rickettsial cases diagnosed at the national reference laboratory between 2015 and 2022.

Methods: Samples testing positive for spotted fever group, typhus group, and scrub typhus IgG/IgM on acute and convalescent blood samples, and/or PCR on tissue/blood were categorized as suspected, confirmed or past infection.

Results: 220 patients had rickettsioses, and the commonest import was acute spotted fever group infection (61%, 125/205), 54% (62/114) from South Africa. In acute typhus group cases, 60% (40/67) were from Southeast Asia. One patient with Rickettsia typhi bacteremia died. Scrub typhus group infections (5%, 10/205) were exclusively from Asia and the Western Pacific regions. Overall, 43% of confirmed cases (39/91) had not received doxycycline prior to results.

Conclusions: Rickettsial infections are important and under-recognized causes of imported fever in the UK. Thorough history, examination, and timely treatment with doxycycline should be considered if there is suspicion of Rickettsia infection before testing.

Keywords: Eschar; Fever; Murine typhus; Rickettsia; Scrub typhus; Spotted fever; Tick.

MeSH terms

Doxycycline / therapeutic use
Humans
Rickettsia Infections* / diagnosis
Rickettsia Infections* / epidemiology
Rickettsia Infections* / microbiology
Rickettsia*
Scrub Typhus* / diagnosis
Scrub Typhus* / epidemiology
Scrub Typhus* / microbiology
Spotted Fever Group Rickettsiosis* / diagnosis
Spotted Fever Group Rickettsiosis* / epidemiology
Typhus, Epidemic Louse-Borne*

Substances

Doxycycline