Plasmodium vivax and Plasmodium falciparum at the Crossroads of Exchange among Islands in Vanuatu: Implications for Malaria Elimination Strategies

Background: The Asia-Pacific region has made significant progress in combatting malaria since 2000 and a regional goal for a malaria-free Asia Pacific by 2030 has been recognised at the highest levels. External financing has recently plateaued and with competing health risks, countries face the risk of withdrawal of funding as malaria is perceived as less of a threat. An investment case was developed to provide economic evidence to inform policy and increase sustainable financing. Methods: A dynamic epidemiological-economic model was developed to project rates of decline to elimination by 2030 and determine the costs for elimination in the Asia-Pacific region. The compartmental model was used to capture the dynamics of Plasmodium falciparum and Plasmodium vivax malaria for the 22 countries in the region in a metapopulation framework. This paper presents the model development and epidemiological results of the simulation exercise. Results: The model predicted that all 22 countries could achieve Plasmodium falciparum and Plasmodium vivax elimination by 2030, with the People’s Democratic Republic of China, Sri Lanka and the Republic of Korea predicted to do so without scaling up current interventions. Elimination was predicted to be possible in Bangladesh, Bhutan, Malaysia, Nepal, Philippines, Timor-Leste and Vietnam through an increase in long-lasting insecticidal nets (and/or indoor residual spraying) and health system strengthening, and in the Democratic People’s Republic of Korea, India and Thailand with the addition of innovations in drug therapy and vector control. Elimination was predicted to occur by 2030 in all other countries only through the addition of mass drug administration to scale-up and/or innovative activities. Conclusions: This study predicts that it is possible to have a malaria-free region by 2030. When computed into benefits and costs, the investment case can be used to advocate for sustained financing to realise the goal of malaria elimination in Asia-Pacific by 2030.

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Early transmission of sensitive strain slows down emergence of drug resistance in Plasmodium vivax

10.1101/603597 ◽

2019 ◽

Author(s):

Mario J.C. Ayala ◽

Daniel A.M. Villela

Keyword(s):

Drug Resistance ◽

Plasmodium Falciparum ◽

Life Cycle ◽

Combination Therapy ◽

Differential Equations ◽

Ordinary Differential Equations ◽

Plasmodium Vivax ◽

Malaria Elimination ◽

Human Population ◽

Model Structure

AbstractThe spread of drug resistance of Plasmodium falciparum and Plasmodium vivax parasites is a challenge towards malaria elimination.P. falciparum has shown an early and severe drug resistance in comparison to P. vivax in various countries. In fact, these Plasmodium species differ in their life cycle and treatment in various factors: development and duration of sexual parasite forms differ, symptoms severity are unequal, relapses present only in P. vivax cases, and the Artemisinin-based combination therapy (ACT) is only mandatory in all P. falciparum cases. We compared the spread of drug resistance for both species through two compartmental models using ordinary differential equations. The model structure describes how sensitive and resistant parasite strains infect a human population treated with antimalarials. We found that the early transmission before treatment and the low effectiveness of drug coverage support the prevalence of sensitive parasites delaying the emergence of resistant P. vivax. These results imply that earlier attention of symptomatic and reservoirs of P. vivax accelerates the spread of drug resistance as P. falciparum.

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Plasmodium vivax and Plasmodium ovale in the Malaria Elimination Agenda in Africa

Current Topics and Emerging Issues in Malaria Elimination - Infectious Diseases ◽

10.5772/intechopen.96867 ◽

2021 ◽

Author(s):

Isaac K. Quaye ◽

Larysa Aleksenko

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Vivax ◽

Malaria Elimination ◽

Sub Saharan Africa ◽

Roll Back Malaria ◽

Plasmodium Ovale ◽

Sub Saharan ◽

Roll Back ◽

Duffy Negative ◽

A Current

In recent times, several countries in sub-Saharan Africa have reported cases of Plasmodium vivax (Pv) with a considerable number being Duffy negative. Current efforts at malaria elimination are focused solely on Plasmodium falciparum (Pf) excluding non-falciparum malaria. Pv and Plasmodium ovale (Po) have hypnozoite forms that can serve as reservoirs of infection and sustain transmission. The burden of these parasites in Africa seems to be more than acknowledged, playing roles in migrant and autochthonous infections. Considering that elimination and eradication is a current aim for WHO and Roll Back Malaria (RBM), the inclusion of Pv and Po in the elimination agenda cannot be over-emphasized. The biology of Pv and Po are such that the same elimination strategies as are used for Pf cannot be applied so, going forward, new approaches will be required to attain elimination and eradication targets.

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Malaria elimination transmission and costing in the Asia-Pacific: a multi-species dynamic transmission model

Wellcome Open Research ◽

10.12688/wellcomeopenres.14771.2 ◽

2019 ◽

Vol 4 ◽

pp. 62 ◽

Cited By ~ 5

Author(s):

Sheetal Prakash Silal ◽

Rima Shretta ◽

Olivier J. Celhay ◽

Chris Erwin Gran Mercado ◽

Sompob Saralamba ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Vivax ◽

Malaria Elimination ◽

Health System Strengthening ◽

Republic Of Korea ◽

Asia Pacific ◽

Transmission Model ◽

Pacific Region ◽

Asia Pacific Region ◽

Free Region

Background: The Asia-Pacific region has made significant progress in combatting malaria since 2000 and a regional goal for a malaria-free Asia Pacific by 2030 has been recognised at the highest levels. External financing has recently plateaued and with competing health risks, countries face the risk of withdrawal of funding as malaria is perceived as less of a threat. An investment case was developed to provide economic evidence to inform policy and increase sustainable financing. Methods: A dynamic epidemiological-economic model was developed to project rates of decline to elimination by 2030 and determine the costs for elimination in the Asia-Pacific region. The compartmental model was used to capture the dynamics of Plasmodium falciparum and Plasmodium vivax malaria for the 22 countries in the region in a metapopulation framework. This paper presents the model development and epidemiological results of the simulation exercise. Results: The model predicted that all 22 countries could achieve Plasmodium falciparum and Plasmodium vivax elimination by 2030, with the People’s Democratic Republic of China, Sri Lanka and the Republic of Korea predicted to do so without scaling up current interventions. Elimination was predicted to be possible in Bangladesh, Bhutan, Malaysia, Nepal, Philippines, Timor-Leste and Vietnam through an increase in long-lasting insecticidal nets (and/or indoor residual spraying) and health system strengthening, and in the Democratic People’s Republic of Korea, India and Thailand with the addition of innovations in drug therapy and vector control. Elimination was predicted to occur by 2030 in all other countries only through the addition of mass drug administration to scale-up and/or innovative activities. Conclusions: This study predicts that it is possible to have a malaria-free region by 2030. When computed into benefits and costs, the investment case can be used to advocate for sustained financing to realise the goal of malaria elimination in Asia-Pacific by 2030.

Download Full-text