Epidemiology and clinical features of imported malaria in East London.
BACKGROUND
Malaria is the most common imported tropical disease in the United Kingdom (UK). The overall mortality is low but inter-regional differences have been observed.


METHODS
We conducted a 2-year retrospective review of clinical and laboratory records of patients with malaria attending three acute hospitals in East London from 1 April 2013 through 31 March 2015. Epidemiological and clinical characteristics of imported malaria were described and risk factors associated with severe falciparum malaria were explored.


RESULTS
In total, 133 patients with laboratory-confirmed malaria were identified including three requiring critical care admission but no deaths. The median age at presentation was 41 years (IQR 30-50). The majority of patients were males (64.7%, 86/133) and had Black or Black British ethnicity (67.5%, 79/117). West Africa was the most frequent region of travel (70.4%, 76/108). Chemoprophylaxis use was poor (25.3%, 20/79). The interval between arriving in the UK and presenting to hospital was short (median 10 days; IQR 5-15.5, n = 84). July-September was the peak season of presentation (34.6%, 46/133). Plasmodium falciparum was the commonest species (76.7%, 102/133) and 31.4% (32/102) of these patients had parasitaemia >2%. Severe falciparum malaria was documented in 36.3% (37/102) of patients and the October-March season presentation was associated with an increased risk of severity (OR 3.00; 95% CI 1.30-6.93). Black patients appeared to have reduced risk of severe falciparum malaria (OR 0.46; 95% CI 0.16-1.35) but this was not statistically significant. HIV sero-status was determined in only 27.1% (36/133) of cases. Only 8.5% (10/117) of all malaria patients were treated as outpatients.


CONCLUSIONS
Clinicians need to raise awareness on malaria prevention strategies, improve rates of HIV testing in tropical travellers, and familiarise themselves with ambulatory management of malaria. The relationship between season of presentation, ethnicity and severity of falciparum malaria should be explored further.
Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK.
Benjamin C
BC
Francis
Department of Infection, Royal London Hospital, Barts Health NHS Trust, 80 Newark Street, London, E1 2ES, UK.
Ximena
X
Gonzalo
Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK.
Sirisha
S
Duggineni
Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
Janice M
JM
Thomas
Department of Infection, Royal London Hospital, Barts Health NHS Trust, 80 Newark Street, London, E1 2ES, UK.
Caoimhe
C
NicFhogartaigh
Department of Infection, Royal London Hospital, Barts Health NHS Trust, 80 Newark Street, London, E1 2ES, UK zahirbabiker@doctors.org.uk zahir_babiker@yahoo.co.uk.
Zahir Osman Eltahir
ZO
Babiker
D000328:Adult; D000368:Aged; D000962:Antimalarials / Q000627:therapeutic use; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008131:London / Q000453:epidemiology; D008288:Malaria / Q000175:diagnosis* / Q000453:epidemiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D012189:Retrospective Studies; D012307:Risk Factors; D014195:Travel / Q000706:statistics & numerical data*
D000962:Antimalarials
Imported malaria; United Kingdom; epidemiology