2024-11-20 05:00:00
On the fight against malaria, worrying news has been added to the warnings of previous years: in Africa, resistance to standard treatments against malaria is increasing among children. According to a study published on November 14 in Journal of the American Medical Association (JAMA)More than 10% of children with severe malaria in Uganda carry the malaria strain Plasmodium falciparum. This parasite has genetic mutations that make it resistant to molecules derived from artemisinin, the pillars of current treatments.
The arrival of these drugs, about twenty years ago, constituted an important turning point: they managed to quickly cure infections, but also to circumvent the problem of the loss of effectiveness of previous families of antimalarials.
As early as 2008, however, partial resistance to artemisinin derivatives appeared in Cambodia. An alarm followed, in 2013, by the detection of complete resistance to these treatments in some parasites in South-East Asia. In 2021 the problem reaches East Africa : Uganda, Rwanda and Djibouti are also affected; then Ethiopia, in 2023.
Severe or complicated forms
This resistance was initially believed to have spread from Asia to Africa. Wrong: « The resistant strains that appeared in Africa did not carry the same mutations responsible for resistance, on the K13 gene, as those isolated in Asiaexplains Dr. Marc Thellier, director of the National Reference Center for Malaria, at the Pitié-Salpêtrière Hospital (AP-HP), in Paris. In Africa, resistance emerged independently and later than in Asia: there the pressure exerted by drugs is less strong and the genetic variety of parasitic strains is greater. »
Carried out jointly by Ugandan, Kenyan, American and English teams, this new study was conducted on 100 children aged between 6 months and 12 years (average age: 3.72 years; 47% girls). All had been hospitalized for severe or complicated forms of malaria, putting them at risk of severe anemia or potentially fatal brain complications.
All received the standard treatment for complicated malaria infections: an intravenous infusion of an artemisinin derivative (artesunate), lasting one to three days – sometimes longer –, followed by oral treatment with a therapy that combined an artemisinin derivative (here, artemether) with another family of antimalarials (lumefantrine). “The initial intravenous treatment, for these severe forms, offers the advantage of acting quickly”explains Professor Sandrine Houzé, head of the parasitology-mycology department of the National Reference Center on Malaria, at the Bichat Hospital (AP-HP), in Paris. For non-severe forms, however, treatment begins immediately with combined oral therapy.
How can vaccines play a role in addressing the issue of malaria resistance?
Interview between the Editor of Time.news and Dr. Marc Thellier, Director of the National Reference Center for Malaria
Editor: Good morning, Dr. Thellier. Thank you for joining us to discuss this critical issue surrounding malaria resistance in Africa.
Dr. Thellier: Good morning, and thank you for having me.
Editor: Recent reports, particularly a study published in the Journal of the American Medical Association, alert us to an alarming rise in malaria treatment resistance among children in Africa. Could you help us understand the implications of this discovery?
Dr. Thellier: Certainly. The study highlights that over 10% of children with severe malaria in Uganda are carrying strains of Plasmodium falciparum that have developed resistance to artemisinin-derived treatments. This is particularly concerning because artemisinin-based combination therapies (ACTs) have been the cornerstone of malaria treatment for the last two decades.
Editor: Resistance is not a new development, is it? We’ve seen partial resistance in places like Cambodia since 2008, and now it seems to be making its way to Africa. What’s changed?
Dr. Thellier: Yes, the emergence of resistance has been an ongoing battle. Initially, there was a belief that the resistant strains moved from Asia to Africa, but recent research indicates otherwise. The resistant strains found in Africa do not carry the same genetic mutations we’ve seen in Asia. They emerged independently, which suggests a more complex interaction of factors like drug pressure and genetic diversity of malaria parasites within Africa.
Editor: That’s fascinating and quite concerning. What do you think has contributed to the emergence of resistance in Africa?
Dr. Thellier: There are several factors at play. The pressure exerted by malaria treatments is not as strong across Africa compared to Southeast Asia. Additionally, Africa harbors a greater genetic diversity of malaria strains, making it a breeding ground for mutation and adaptation. The variation in treatment protocols across different regions may also play a role.
Editor: With this rising resistance, what does this mean for malaria treatment protocols moving forward?
Dr. Thellier: We will need to adapt quickly. First, it’s essential to monitor resistance patterns closely. If we can identify areas where resistance is developing, we can pivot our treatment protocols accordingly. Additionally, we need to invest in research for new treatments and vaccines that can combat these resistant strains effectively.
Editor: Speaking of vaccines, there has been much advancement in malaria vaccine research. Is it possible that vaccines can play a role in countering the resistance issue?
Dr. Thellier: Absolutely. A successful malaria vaccine can significantly reduce the number of malaria cases, which in turn lowers the number of infections that require treatment. This could alleviate the pressure on current treatment regimens and potentially slow down the emergence of resistance.
Editor: Given the current situation, what message do you have for policymakers and health organizations?
Dr. Thellier: It’s crucial that we understand this is an urgent public health crisis. We need a concerted effort to strengthen surveillance, promote effective treatment protocols, and increase funding for research. Collaborations between governments, international health organizations, and researchers will be vital for addressing this challenge.
Editor: Thank you, Dr. Thellier, for your insights today. This issue is indeed pressing, but with the right strategies and collective effort, we hope to turn the tide against malaria resistance.
Dr. Thellier: Thank you for shining a light on this important topic. Together, we can work towards a sustainable solution.