Managing childhood malaria in rural Tanzania : focusing on drug use and resistance

Background: Malaria is a leading cause of death in underfive children in Africa. Due to the spread of chloroquine (CQ) resistance, sub-Saharan African countries such as Tanzania have changed their malaria treatment policies. In 2001 Tanzania replaced CQ with sulfadoxine/pyrimethamine (SP) as first line malaria treatment. Resistance to SP is known to develop fast and little is known about how a new policy is adopted.

Main aim: The aim was to explore the influence of the national malaria policy change on malaria case management of children under five and development of resistance to antimalarials in rural Tanzania.

Methods: The thesis consists of five cross-sectional studies performed in three different rural districts of Tanzania. During data collection, the national malaria treatment policy was changed and our studies were patterned accordingly: two studies were conducted before (I & II) and three studies after (III, IV & V) the policy change. Four studies were conducted at health facility level (I, II, IV & V) and one was conducted in the community (III). Consultations of 652 and 117 underfives, attending all public primary health facilities in Kibaha district (I) and eight health facilities in Mkuranga district (IV), respectively, were observed and mothers/guardians were interviewed upon exit. Caretakers in 729 randomly selected households in Kibaha district were interviewed about knowledge of the new malaria treatment policy and FGDs were performed with caretakers and health professionals (III). In Kilosa district we assessed efficacy of SP and CQ before the policy change (II) and SP and Amodiaquine (AQ) after the policy change (V). In study II and V, 117 and 96 underfives with malaria, respectively, were treated with the mentioned drugs. Clinical status, parasite densities, blood drug levels, haemoglobin levels and parasite mutations were monitored for 28 days. In all studies (I-V), blood was sampled from children and analysed for antimalarial content.

Results: Before the policy change , quality of care was poor in terms of history taking, physical examination and prescribing. Self-treatment was common as 98% of children had detectable CQ in blood prior to seeking formal health care (I). Clinical failure rates with CQ and SP were only 10% and 2%, respectively, despite high drug pressure in the community (II). Six months after the policy change, 51% of caretakers knew that SP was the new first line treatment. Interviewees reported seeking care at public health facilities instead of self-treatment and only 18% of children had measurable levels of SP in blood (III). Although quality of care was still poor and health workers scored 18% when performance was assessed by quality indicators, most febrile children (89%) received antimalarial treatment, in line with guideline recommendations (IV). SP resistance levels had not increased and drug pressure was lower than before the policy change (V).

Discussion: Progression of resistance to SP was not seen despite its use as first line treatment for three years (II & V), probably caused by changed drug use and thereby decreased drug pressure (I-V). Although the thesis mainly consists of data from health facilities, the findings indicate that the Tanzanian policy diffused well to the studied community (III). Quality of diagnosis at health facilities was poor (I & IV). Future malaria treatment policies include challenges such as high drug costs and poor compliance. In this aspect, inhibited drug resistance and changed patterns of drug use is positive, but quality of care at health facilities needs to be improved.

List of scientific papers

I. Nsimba SE, Massele AY, Eriksen J, Gustafsson LL, Tomson G, Warsame M (2002). Case management of malaria in under-fives at primary health care facilities in a Tanzanian district. Trop Med Int Health. 7(3): 201-9.
https://pubmed.ncbi.nlm.nih.gov/11903982

II. Eriksen J, Mwankusye S, Mduma S, Kitua A, Swedberg G, Tomson G, Gustafsson LL, Warsame M (2004). Patterns of resistance and DHFR/DHPS genotypes of Plasmodium falciparum in rural Tanzania prior to the adoption of sulfadoxine-pyrimethamine as first-line treatment. Trans R Soc Trop Med Hyg. 98(6): 347-53.
https://pubmed.ncbi.nlm.nih.gov/15099990

III. Eriksen J, Nsimba SE, Minzi OM, Sanga AJ, Petzold M, Gustafsson LL, Warsame MY, Tomson G (2005). Adoption of the new antimalarial drug policy in Tanzania--a cross-sectional study in the community. Trop Med Int Health. 10(10): 1038-46.
https://pubmed.ncbi.nlm.nih.gov/16185239

IV. Eriksen J, Tomson G, Mujinja P, Jahn A, Warsame M, Gustafsson LL (2006). Assessing health worker performance in malaria case management of underfives at health facilities in a rural Tanzanian district. [Submitted]

V. Eriksen J, Tomson G, Mwankusye S, Mduma S, Kitua A, Petzold MG, Veiga MI, Swedberg G, Gustafsson LL, Warsame M (2006). Three years with sulfadoxine/pyrimethamine as first-line treatment of uncomplicated falciparum malaria in rural Tanzania - efficacy unchanged. [Submitted]