Malaria hospitalisation in East Africa: age, phenotype and transmission intensity



BACKGROUND: Understanding the age patterns of disease is necessary to target interventions to maximise cost-effective impact. New malaria chemoprevention and vaccine initiatives target young children attending routine immunisation services. Here we explore the relationships between age and severity of malaria hospitalisation versus malaria transmission intensity. METHODS: Clinical data from 21 surveillance hospitals in East Africa were reviewed. Malaria admissions aged 1 month to 14 years from discrete administrative areas since 2006 were identified. Each site-time period was matched to a model estimated community-based age-corrected parasite prevalence to provide predictions of prevalence in childhood (PfPR2-10). Admission with all-cause malaria, severe malaria anaemia (SMA), respiratory distress (RD) and cerebral malaria (CM) were analysed as means and predicted probabilities from Bayesian generalised mixed models. RESULTS: 52,684 malaria admissions aged 1 month to 14 years were described at 21 hospitals from 49 site-time locations where PfPR2-10 varied from < 1 to 48.7%. Twelve site-time periods were described as low transmission (PfPR2-10 < 5%), five low-moderate transmission (PfPR2-10 5-9%), 20 moderate transmission (PfPR2-10 10-29%) and 12 high transmission (PfPR2-10 >/= 30%). The majority of malaria admissions were below 5 years of age (69-85%) and rare among children aged 10-14 years (0.7-5.4%) across all transmission settings. The mean age of all-cause malaria hospitalisation was 49.5 months (95% CI 45.1, 55.4) under low transmission compared with 34.1 months (95% CI 30.4, 38.3) at high transmission, with similar trends for each severe malaria phenotype. CM presented among older children at a mean of 48.7 months compared with 39.0 months and 33.7 months for SMA and RD, respectively. In moderate and high transmission settings, 34% and 42% of the children were aged between 2 and 23 months and so within the age range targeted by chemoprevention or vaccines. CONCLUSIONS: Targeting chemoprevention or vaccination programmes to areas where community-based parasite prevalence is >/=10% is likely to match the age ranges covered by interventions (e.g. intermittent presumptive treatment in infancy to children aged 2-23 months and current vaccine age eligibility and duration of efficacy) and the age ranges of highest disease burden.

Kamau, A., Paton, R. S., Akech, S., Mpimbaza, A., Khazenzi, C., Ogero, M., Mumo, E., Alegana, V. A., Agweyu, A., Mturi, N., Mohammed, S., Bigogo, G., Audi, A., Kapisi, J., Sserwanga, A., Namuganga, J. F., Kariuki, S., Otieno, N. A., Nyawanda, B. O., Olotu, A., Salim, N., Athuman, T., Abdulla, S., Mohamed, A. F., Mtove, G., Reyburn, H., Gupta, S., Lourenco, J., Bejon, P., Snow, R. W.

Pages:28, Volume:20, Edition:1/28/2022, Date,Jan-27


Notes:Kamau, Alice|Paton, Robert S|Akech, Samuel|Mpimbaza, Arthur|Khazenzi, Cynthia|Ogero, Morris|Mumo, Eda|Alegana, Victor A|Agweyu, Ambrose|Mturi, Neema|Mohammed, Shebe|Bigogo, Godfrey|Audi, Allan|Kapisi, James|Sserwanga, Asadu|Namuganga, Jane F|Kariuki, Simon|Otieno, Nancy A|Nyawanda, Bryan O|Olotu, Ally|Salim, Nahya|Athuman, Thabit|Abdulla, Salim|Mohamed, Amina F|Mtove, George|Reyburn, Hugh|Gupta, Sunetra|Lourenco, Jose|Bejon, Philip|Snow, Robert W|eng|5U01GH000048/CC/CDC HHS/|5NU2GGH001744-02-00/CC/CDC HHS/|207522/WT_/Wellcome Trust/United Kingdom|211208/Z/18/Z/WT_/Wellcome Trust/United Kingdom|211208/WT_/Wellcome Trust/United Kingdom|097170/WT_/Wellcome Trust/United Kingdom|MR/R006083/1/MRC_/Medical Research Council/United Kingdom|WT_/Wellcome Trust/United Kingdom|212176/WT_/Wellcome Trust/United Kingdom|MR/R006083/1/Medical Research Foundation|203077/WT_/Wellcome Trust/United Kingdom|Research Support, Non-U.S. Gov’t|Research Support, U.S. Gov’t, Non-P.H.S.|Research Support, U.S. Gov’t, P.H.S.|England|2022/01/28 06:00|BMC Med. 2022 Jan 27;20(1):28. doi: 10.1186/s12916-021-02224-w.

ISBN: 1741-7015 (Electronic)|1741-7015 (Linking) Permanent ID: PMC8793189 Accession Number: 35081974

Author Address: Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, Nairobi, Kenya.|Department of Zoology, University of Oxford, Oxford, UK.|Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, Nairobi, Kenya.|Child Health and Development Centre, College of Health Sciences, Makerere University, Kampala, Uganda.|Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, Kilifi, Kenya.|Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya.|Infectious Diseases Research Collaboration, Kampala, Uganda.|Ifakara Health Institute, Bagamoyo, Tanzania.|Kilimanjaro Christian Medical Centre/Joint Malaria Programme, Moshi, Tanzania.|London School of Hygiene and Tropical Medicine, London, UK.|National Institute for Medical Research, Amani Research Centre, Muheza, Tanzania.|Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.