Article
Microbiology
Achaporn Yipsirimetee, Pornpawee Chiewpoo, Rupam Tripura, Dysoley Lek, Nicholas P. J. Day, Arjen M. Dondorp, Sasithon Pukrittayakamee, Nicholas J. White, Kesinee Chotivanich
Summary: In this study, the activities of cipargamin, ganaplacide, and artesunate against artemisinin-resistant Plasmodium falciparum isolates were compared. Ganaplacide exhibited higher activities than cipargamin and artesunate, and both cipargamin and ganaplacide showed significant transmission-blocking activities against artemisinin-resistant Plasmodium falciparum.
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
(2022)
Article
Parasitology
Benyl M. Ondeto, Xiaoming Wang, Harrysone Atieli, Daibin Zhong, Guofa Zhou, Ming-Chieh Lee, Pauline Winnie Orondo, Kevin O. Ochwedo, Collince J. Omondi, Simon M. Muriu, David O. Odongo, Horace Ochanda, James Kazura, Andrew K. Githeko, Guiyun Yan
Summary: Despite initial reductions in asymptomatic malaria parasite prevalence among school children from 2005 to 2008 in all sites, a resurgence of parasite prevalence by over 40% has been observed in Kombewa and Marani since 2011. The study also found that Kombewa had a higher risk of infection compared to Iguhu and Marani.
PARASITES & VECTORS
(2022)
Article
Immunology
Daniela Barbieri, Lina Gomez, Ludivine Royer, Florian Dupuy, Jean-Francois Franetich, Maurel Tefit, Marie-Esther N'Dri, Dominique Mazier, Olivier Silvie, Alicia Moreno-Sabater, Catherine Lavazec
Summary: In this study, it was found that the drug tadalafil can block malaria parasite transmission by altering the mechanical properties of infected erythrocytes. Results from in vivo experiments using a humanized mouse model showed that tadalafil treatment increased the stiffness of gametocyte-infected erythrocytes, leading to their retention by the spleen.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2022)
Article
Cell Biology
Melanie C. Ridgway, Daniela Cihalova, Simon H. J. Brown, Phuong Tran, Todd W. Mitchell, Alexander G. Maier
Summary: Male and female Plasmodium falciparum gametocytes play a key role in the transmission of malaria from human hosts to mosquito vectors. Research shows significant differences in lipid composition between male and female gametocytes, with female gametocytes enriched in cholesteryl esters and dihydrosphingomyelin. The study highlights the potential of targeting sex-specific gametocyte lipid metabolism as a strategy to block malaria transmission.
JOURNAL OF CELL SCIENCE
(2022)
Article
Immunology
John Rek, Sara Lynn Blanken, Joseph Okoth, Daniel Ayo, Ismail Onyige, Eric Musasizi, Jordache Ramjith, Chiara Andolina, Kjerstin Lanke, Emmanuel Arinaitwe, Peter Olwoch, Katharine A. Collins, Moses R. Kamya, Grant Dorsey, Chris Drakeley, Sarah G. Staedke, Teun Bousema, Melissa D. Conrad
Summary: This study in a high malaria transmission area in Uganda found that school-aged children and asymptomatic infections are major contributors to the malaria human infectious reservoir. Understanding the transmissibility of human infections in different settings is crucial for achieving malaria elimination. It was determined that asymptomatic infections had a higher impact on transmission compared to symptomatic infections.
JOURNAL OF INFECTIOUS DISEASES
(2022)
Article
Microbiology
Marta Tiburcio, Eva Hitz, Igor Niederwieser, Gavin Kelly, Heledd Davies, Christian Doerig, Oliver Billker, Till S. Voss, Moritz Treeck
Summary: Malaria is a mosquito-borne disease caused by Plasmodium parasites, with sexual commitment in a small fraction of asexual blood-stage parasites initiated by external cues. The study found that a truncation in the extreme C terminus of the GDV1 protein affects its protein levels and sexual commitment, highlighting the important role of the GDV1 C terminus beyond trafficking and protein stability.
Article
Immunology
Elizabeth Hemming-Schroeder, Daibin Zhong, Solomon Kibret, Amanda Chie, Ming-Chieh Lee, Guofa Zhou, Harrysone Atieli, Andrew Githeko, James W. Kazura, Guiyun Yan
Summary: Investments in irrigated agriculture are expected to increase in Africa to improve food security, but the impact of environmental changes from water resource development on malaria epidemiology remains unclear. This study compared molecular markers in deep amplicon sequencing for evaluating malaria transmission intensities and found that the cpmp amplicon had the highest sensitivity. Malaria transmission intensity was highest within 5 km of the irrigation scheme, with the irrigated area serving as a source of parasite infections for surrounding areas.
JOURNAL OF INFECTIOUS DISEASES
(2021)
Review
Public, Environmental & Occupational Health
Anna Maria van Eijk, Kasia Stepniewska, Jenny Hill, Steve M. Taylor, Stephen J. Rogerson, Gilles Cottrell, R. Matthew Chico, Julie R. Gutman, Halidou Tinto, Holger W. Unger, Stephanie K. Yanow, Steven R. Meshnick, Feiko O. ter Kuile, Alfredo Mayor, Subpatent Malaria Pregnancy Grp
Summary: This study aimed to describe the epidemiology of submicroscopic malaria infections in pregnant women in Asia, the Americas, and Africa. It found that submicroscopic infections were more common than microscopic infections during pregnancy, and were associated with fever in Africa. Therefore, malaria control in pregnancy should target both microscopic and submicroscopic infections.
LANCET GLOBAL HEALTH
(2023)
Article
Multidisciplinary Sciences
Isaiah Debrah, Yaw A. Afrane, Linda E. Amoah, Kevin O. Ochwedo, Wolfgang R. Mukabana, Daibin Zhong, Guofa Zhou, Ming-Chieh Lee, Shirley A. Onyango, Edwin O. Magomere, Harrysone Atieli, Andrew K. Githeko, Guiyun Yan
Summary: In this study, the larval ecology, sporozoite infection rates and blood meal sources of An. funestus in western Kenya were investigated. The highest abundance of An. funestus larvae was found in man-made ponds, and the distance to the nearest house was identified as the key environmental factor associated with the abundance of An. funestus larvae in aquatic habitats. This study provides valuable insights for the control of An. funestus and other mosquito species to complement existing vector control strategies.
Article
Infectious Diseases
Collince J. Omondi, Wilfred O. Otambo, David Odongo, Kevin O. Ochwedo, Antony Otieno, Shirley A. Onyango, Pauline Orondo, Benyl M. Ondeto, Ming-Chieh Lee, Daibin Zhong, James W. Kazura, Andrew K. Githeko, Guiyun Yan
Summary: This study evaluated the impact of LLINs integrated with IRS on the prevalence of asymptomatic and submicroscopic Plasmodium infections in Homa Bay County. The results showed that two annual rounds of IRS significantly reduced the prevalence of Plasmodium parasitaemia, while the proportion of asymptomatic and submicroscopic infections increased.
Article
Microbiology
Kathrin Witmer, Farah A. Dahalan, Michael J. Delves, Sabrina Yahiya, Oliver J. Watson, Ursula Straschil, Darunee Chiwcharoen, Boodtee Sornboon, Sasithon Pukrittayakamee, Richard D. Pearson, Virginia M. Howick, Mara K. N. Lawniczak, Nicholas J. White, Arjen M. Dondorp, Lucy C. Okell, Kesinee Chotivanich, Andrea Ruecker, Jake Baum
Summary: Resistance to artemisinin-based combination therapy (ACT) in the Plasmodium falciparum parasite threatens recent progress in reducing global malaria deaths. Under artemisinin drug pressure, resistant parasites have a selective advantage in transmission, potentially leading to the spread of multidrug-resistant malaria beyond Southeast Asia.
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
(2021)
Article
Immunology
Michelle K. Muthui, Eizo Takashima, Brian R. Omondi, Christine Kinya, William I. Muasya, Hikaru Nagaoka, Kennedy W. Mwai, Benedict Orindi, Juliana Wambua, Teun Bousema, Chris Drakeley, Andrew M. Blagborough, Kevin Marsh, Philip Bejon, Melissa C. Kapulu
Summary: Naturally acquired immunity to gametocyte antigens plays a crucial role in interrupting transmission, influenced by age and concurrent parasitaemia. Novel candidates for evaluating transmission-blocking activity have been identified in this study.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2021)
Article
Microbiology
Jonas A. Kengne-Ouafo, Saikou Y. Bah, Alison Kemp, Lindsay Stewart, Lucas Amenga-Etego, Kirk W. Deitsch, Julian C. Rayner, Oliver Billker, Fred N. Binka, Colin J. Sutherland, Gordon A. Awandare, Britta C. Urban, Bismarck Dinko
Summary: Recent advances in transcriptomic analysis have greatly improved our understanding of the developmental biology of malaria parasites. However, most studies have relied on laboratory strains and have not assessed the transcriptomes of clinical isolates. This study compared the global transcriptome of mid-stage gametocytes from three clinical isolates with a laboratory strain, revealing both consistencies and differences in gene expression.
MICROBIOLOGY SPECTRUM
(2023)
Article
Immunology
Oriana Kreutzfeld, Patrick K. Tumwebaze, Oswald Byaruhanga, Thomas Katairo, Martin Okitwi, Stephen Orena, Stephanie A. Rasmussen, Jennifer Legac, Melissa D. Conrad, Sam L. Nsobya, Ozkan Aydemir, Jeffrey A. Bailey, Maelle Duffey, Roland A. Cooper, Philip J. Rosenthal
Summary: This study investigated the susceptibility of P falciparum field isolates to PfDHFR inhibitors in two districts of Uganda and found common resistance-mediating mutations in Uganda. However, the new compound P218 retained excellent activity against mutant parasites.
JOURNAL OF INFECTIOUS DISEASES
(2022)
Article
Microbiology
Jonas A. Kengne-Ouafo, Saikou Y. Bah, Alison Kemp, Lindsay Stewart, Lucas Amenga-Etego, Kirk W. Deitsch, Julian C. Rayner, Oliver Billker, Fred N. Binka, Colin J. Sutherland, Gordon A. Awandare, Britta C. Urban, Bismarck Dinko
Summary: Recent advances in transcriptomic analysis have greatly enhanced our understanding of the developmental biology of malaria parasites. However, there is a lack of assessment on the transcriptomes of clinical isolates circulating in human populations. In this study, RNA-seq was used to compare the global transcriptome of mid-stage gametocytes derived from clinical isolates with a reference laboratory strain. The results showed differences in gene expression profiles between the clinical isolates and the reference strain, suggesting increased investment in gametocytogenesis in clinical isolates.
MICROBIOLOGY SPECTRUM
(2023)
Article
Obstetrics & Gynecology
George Mtove, Omari Abdul, Fanny Kullberg, Samwel Gesase, Thomas Scheike, Frederik Molkjaer Andersen, Mwayiwawo Madanitsa, Feiko O. Kuile, Michael Alifrangis, John P. A. Lusingu, Daniel T. R. Minja, Christentze Schmiegelow
Summary: This study aimed to generate sex-specific prediction maps and weight reference charts for the retrospective estimation of birthweight for exclusively breastfed newborns in a low-resource setting. The results showed the rapid decline in weight shortly after delivery, and the prediction maps and reference charts can be used to better assess the weight of newborns and estimate birthweight retrospectively.
ACTA OBSTETRICIA ET GYNECOLOGICA SCANDINAVICA
(2022)
Article
Public, Environmental & Occupational Health
Queen Saidi, Daniel Minja, Judith Njau, Helle Hansson, Reginald Kavishe, Michael Alifrangis
Summary: This study compared the diagnostic sensitivity of different DNA extraction protocols for detecting low-level Plasmodium falciparum infections. The results showed that using a commercial kit greatly improved the likelihood of detecting positive samples.
AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE
(2022)
Article
Infectious Diseases
Peter Thelma Ngwa Niba, Akindeh Mbuh Nji, Innocent Mbulli Ali, Lawrence Fonyonga Akam, Cedric Hermann Dongmo, Jean Paul Kengne Chedjou, Calvino Tah Fomboh, William Dorian Nana, Ornella Laetitia Ayem Oben, Abdel Aziz Selly-Ngaloumo, Marcel N. Moyeh, Jude Achidi Ngu, Ambassa Jean Ludovic, Pierre Martiniel Aboh, Marie Carine Enyegue Ambani, Pierrette Albertine Mbarga Omgba, Grace Bissohong Kotcholi, Linus Moye Adzemye, Danielle Regine Abenkou Nna, Adele Douanla, Ze Ango, Marie Sophie Ewane, Joel Tewara Ticha, Fritz Mbuh Tatah, Golwa Dinza, Valentine Nchafor Ndikum, Dorothy A. Fosah, Jude D. Bigoga, Michael Alifrangis, Wilfred F. Mbacham
Summary: This study evaluated the effectiveness and safety of AS-AQ and AL for home-based treatment of uncomplicated P. falciparum malaria in Yaounde, Cameroon. The results showed that both AS-AQ and AL were effective and safe for the management of malaria in a home setting.
BMC INFECTIOUS DISEASES
(2022)
Article
Immunology
George O. Adjei, Abdul M. Sulley, Bamenla Q. Goka, Christabel Enweronu-Laryea, Lorna Renner, Michael Alifrangis, Jorgen A. L. Kurtzhals
Summary: The accuracy of rapid diagnostic tests (RDTs) for malaria diagnosis in patients with sickle cell disease (SCD) was evaluated in this study. The HRP-2-based RDTs showed high sensitivity but lower specificity, making them suitable for initiating treatment in cases with unclear symptoms. The LDH-based RDTs were more suitable as a confirmatory test in low-parasitemic subgroups.
CLINICAL INFECTIOUS DISEASES
(2022)
Article
Infectious Diseases
Mahamoudou Toure, Moussa Keita, Fousseyni Kane, Daouda Sanogo, Salim Kante, Drissa Konate, Ayouba Diarra, Nafomon Sogoba, Mamadou B. Coulibaly, Sekou F. Traore, Michael Alifrangis, Mahamadou Diakite, Jeffrey G. Shaffer, Donald J. Krogstad, Seydou Doumbia
Summary: Efficient implementation of two main malaria prevention strategies in Dangassa substantially contributed to the reduction of both asymptomatic and symptomatic malaria from 2015 to 2020.
Article
Entomology
Harilanto Felana Andrianjakarivony, David Damiens, Lucie Marquereau, Benjamin Gaudillat, Nausicaa Habchi-Hanriot, Louis-Clement Gouagna
Summary: The potential interference of releasing millions of sterile male Aedes albopictus on the reproduction of female Aedes aegypti has been studied using a marking technique. The results showed that in small experimental cages, the mating rate between sterile male Aedes albopictus and female Aedes aegypti was very low, indicating that in the field, the frequency of heterospecific mating would be very low.
Article
Multidisciplinary Sciences
Geofrey Makenga, Vito Baraka, Filbert Francis, Daniel T. R. Minja, Samwel Gesase, Edna Kyaruzi, George Mtove, Swabra Nakato, Rashid Madebe, Sif R. Soeborg, Kathrine H. Langhoff, Helle S. Hansson, Michael Alifrangis, John P. A. Lusingu, Jean-Pierre Van Geertruyden
Summary: In Africa, school-aged children are highly burdened by malaria and anaemia, which impair cognitive development. A study found that factors such as malaria infection, anaemia, stunting, and high-endemic areas are associated with anaemia in schoolchildren. However, there was no significant association between malaria infection or anaemia and cognitive and psychomotor functions. These findings are important for improving school health policies and malaria control efforts.
Article
Infectious Diseases
Ayubo Kampango, Emma F. Hocke, Helle Hansson, Peter Furu, Khamis A. Haji, Jean-Philippe David, Flemming Konradsen, Fatma Saleh, Christopher W. Weldon, Karin L. Schioler, Michael Alifrangis
Summary: The study found that Aedes aegypti mosquitoes in hotel compounds on Zanzibar Island were highly resistant to DDT, and possibly resistant to deltamethrin and propoxur, but this resistance was not linked to mutations in the studied genes. The presence of insecticide resistance in Ae. aegypti in hotel compounds could act as sources of resistant mosquitoes. Further research is needed to determine the causes and prevent resistance from spreading.
PLOS NEGLECTED TROPICAL DISEASES
(2022)
Article
Infectious Diseases
Adeola Y. Olukosi, Olusola Ajibaye, Omowunmi Omoniwa, Olusola Oresanya, Aina O. Oluwagbemiga, Chinazo Ujuju, Michael Ekholuenetale, Kolawole Maxwell, Colin J. Sutherland, James K. Tibenderana, Khalid B. Beshir
Summary: A rapid surveillance study was conducted in Ebonyi and Osun states in Nigeria to assess the suitability of sulfadoxine/pyrimethamine (SP) as perennial malaria chemoprevention (PMC). The study revealed that both states are suitable for SP-PMC implementation, and it has been implemented in Osun since 2022. Continuous monitoring of the 540E mutation is necessary to ensure the effectiveness of SP chemoprevention in Nigeria.
JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY
(2023)
Article
Medicine, General & Internal
Mwayiwawo Madanitsa, Hellen C. Barsosio, Daniel T. R. Minja, George Mtove, Reginald A. Kavishe, James Dodd, Queen Saidi, Eric Onyango, Kephas Otieno, Duolao Wang, Ulla Ashorn, Jenny Hill, Crispin Mukerebe, Samwel Gesase, Omari A. Msemo, Victor Mwapasa, Kamija S. Phiri, Kenneth Maleta, Nigel Klein, Pascal Magnussen, John P. A. Lusingu, Simon Kariuki, Jacklin F. Mosha, Michael Alifrangis, Helle Hansson, Christentze Schmiegelow, Julie R. Gutman, R. Matthew Chico, Feiko O. ter Kuile
Summary: This study evaluates the efficacy of intermittent preventive treatment in pregnancy (IPTp) with dihydroartemisinin-piperaquine compared to sulfadoxine-pyrimethamine in high-resistance areas in East Africa. The results demonstrate that IPTp with dihydroartemisinin-piperaquine and its combination with azithromycin lead to more adverse pregnancy outcomes compared to sulfadoxine-pyrimethamine. This suggests that combining sulfadoxine-pyrimethamine and dihydroartemisinin-piperaquine for IPTp should be considered.
Article
Infectious Diseases
Adebanjo J. Adegbola, Omotade A. Ijarotimi, Akaninyene E. Ubom, Bukola A. Adesoji, Olajide E. Babalola, Emma F. Hocke, Helle Hansson, Andria Mousa, Oluseye O. Bolaji, Michael Alifrangis, Cally Roper
Summary: This study aimed to assess the prevalence of Pfdhfr/Pfdhps mutations in P. falciparum isolates from Nigeria and present maps of their distribution. The results showed an increasing prevalence of the VAGKGS haplotype, which may have implications for the efficacy of SP-IPTp and should be reassessed.
Article
Infectious Diseases
Samuel Yao Ahorhorlu, Neils Ben Quashie, Rasmus Weisel Jensen, William Kudzi, Edmund Tetteh Nartey, Nancy Odurowah Duah-Quashie, Felix Zoiku, Bartholomew Dzudzor, Christian William Wang, Helle Hansson, Michael Alifrangis, George Obeng Adjei
Summary: This study aimed to assess and characterize correlates of potential artemisinin tolerance in Plasmodium falciparum isolates from children with uncomplicated malaria in Ghana. The findings suggest that artemisinin-based combination therapy is still effective for treating uncomplicated malaria in Ghana, despite the emerging artemisinin tolerance in some regions of East Africa. The role of two newly identified mutations in drug resistance needs further investigation.
Correction
Multidisciplinary Sciences
Tianyang Liu, Fiona Shilliday, Alexander D. Cook, Mohammad Zeeshan, Declan Brady, Rita Tewari, Colin J. Sutherland, Anthony J. Roberts, Carolyn A. Moores
NATURE COMMUNICATIONS
(2023)
Article
Infectious Diseases
Peter Thelma Ngwa Niba, Akindeh Mbuh Nji, Jean Paul Kengne Chedjou, Helle Hansson, Emma Filtenborg Hocke, Innocent Mbulli Ali, Olivia Achonduh-Atijegbe, Marie-Solange B. Evehe, Marie Helene Munck Jorgensen, Calvino Tah Fomboh, Liwang Cui, Gillian Stresman, Jude D. Bigoga, Michael Alifrangis, Wilfred F. Mbacham
Summary: This study investigated the evolution of Plasmodium falciparum antimalarial drug resistance markers in Yaounde, Cameroon before and after the adoption of artemisinin-based combination therapies (ACTs). The prevalence of certain mutant alleles associated with drug resistance significantly changed over time. There was a decline in the Pfcrt 76T and Pfmdr1 86Y mutant alleles, while the Pfdhfr 51I/59R/108N and Pfdhps 437G mutant alleles increased. Nine mutations were identified in the propeller domains of Pfk13, but none of them were associated with artemisinin resistance. Overall, there was a near-complete reversion to sensitive parasites for markers conferring resistance to certain antimalarial drugs.
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
(2023)
Article
Public, Environmental & Occupational Health
Debora C. Kajeguka, Francis M. Mponela, Emmanuel Mkumbo, Anna N. Kaaya, Daniel Lasway, Robert D. Kaaya, Michael Alifrangis, Emmanuel Elanga-Ndille, Blandina T. Mmbaga, Reginald Kavishe
Summary: Dengue virus is a re-emerging arbovirus of increasing global concern. This study conducted in rural Tanzania found that dengue continues to circulate in the area, with a prevalence of acute infection at 2.2%. The study also identified risk factors for dengue transmission, with adults living in houses with vegetation being more likely to be seropositive, and children living in houses with garbage pits being less likely to be seropositive.
JOURNAL OF TROPICAL MEDICINE
(2023)