Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND:Artemisinin-based combination therapy (ACT) is the global standard of care for uncomplicated falciparum malaria. First reports of ACT resistance came from western Cambodia and the Thailand-Cambodia border in 2002-2004. The subsequent emergence and expansion of Plasmodium falciparum strains resistant to the artemisinin component and ACT are now threatening the efficacy of falciparum malaria treatment. METHODS:We performed a literature review on the history and the current degree of geographic expansion of artemisinin and ACT resistance. Resistance against artemisinins is defined as >5% of patients carrying PfKelch13 (K13) mutations, all of whom have been found to have persistent parasitaemia by microscopy on Day 3 after treatment. RESULTS:Several studies including the multi-centre Tracking Resistance to Artemisinin Collaboration study investigated artemisinin resistance in Southeast Asia and beyond and demonstrated increasing prevalence of P. falciparum infections with slow parasite clearance rates in the Greater Mekong Subregion (GMS). K13 mutations were strongly associated with delayed P. falciparum parasite clearance, and the prevalence of the mutation PfKelch13 C580Y is increasing in the GMS. Resistance to ACT regimens is now well established in western Cambodia and in eastern Thailand, southern Laos and southern Vietnam. Moreover, the prevalence of slow P. falciparum parasite clearance has continuously increased over the past 10-15 years at the Thailand-Myanmar border, in nearly all regions of Myanmar, and at the Myanmar-China border. CONCLUSION:Multidrug resistant malaria is a rapidly increasing problem, but fortunately still limited to Southeast Asia, in particular to the GMS. In the long-term it may threaten global progress in malaria control but is not yet of concern with regards to malaria prophylaxis, as ACTs are not used for prevention in travellers, current ACT regimens are still effective in most malaria endemic areas outside the GMS and the preferred travellers' prophylaxis atovaquone-proguanil and doxycycline remain protective. However, artemsinin resistance in the GMS is of real concern to travellers as it will affect the choice of malaria treatment including standby-emergence treatment.

Original publication

DOI

10.1093/jtm/taz030

Type

Journal

Journal of travel medicine

Publication Date

06/2019

Volume

26

Addresses

Heidelberg Institute of Global Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany.