Dataset Information

Malaria Transmission Dynamics in High Transmission Setting of Western Kenya and the Inadequate Treatment Response to Artemether-lumefantrine in an Asymptomatic Population.

ABSTRACT:

Background

Assessing the infectious reservoir is critical in malaria control and elimination strategies. We conducted a longitudinal epidemiological study in a high malaria burden region in Kenya to characterize transmission in an asymptomatic population.

Methods

488 study participants encompassing all ages in 120 households within 30 clusters were followed for one year with monthly sampling. Malaria was diagnosed by microscopy and molecular methods. Transmission potential in gametocytemic participants were assessed using direct skin and/or membrane mosquito feeding assays, then treated with artemether-lumefantrine. Study variables were assessed using mixed-effects generalized linear models.

Results

Asexual and sexual parasite data was collected from 3,792 participant visits, with 903 linked with feeding assays. Univariate analysis revealed that 6-11-year old age-group were at higher risk of harboring asexual and sexual infections than the less than 6-year-old (Odds Ratio [OR] 1.68, p < 0.001 and OR 1.81, p < 0.001), respectively. Participants with submicroscopic parasitemia were at a lower risk of gametocytemia compared to microscopic (OR 0.04, p < 0.001), but they transmitted at a significantly higher rate (OR 2.00, p = 0.002). A large proportion of the study population was continuously infected (despite treatment) with asexual (71.7%, 291/406) or sexual (37.4%, 152/406) parasites. 89.4% (365/408) of feeding assays conducted in individuals who failed treatment the previous month resulted in transmissions.

Conclusion

Individuals with asymptomatic infection sustain the transmission cycle, with the 6-11-year old age-group serving as an important reservoir. The high rates of artemether-lumefantrine treatment failures suggest surveillance programs using molecular methods need to be expanded for accurate monitoring and evaluation of treatment outcomes.

SUBMITTER: Andagalu B

PROVIDER: S-EPMC9938745 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Publications

Malaria Transmission Dynamics in a High-Transmission Setting of Western Kenya and the Inadequate Treatment Response to Artemether-Lumefantrine in an Asymptomatic Population.

Andagalu Ben B Watson Oliver J OJ Onyango Irene I Opot Benjamin B Okoth Raphael R Chemwor Gladys G Sifuna Peter P Juma Dennis D Cheruiyot Agnes A Yeda Redemptah R Okudo Charles C Wafubwa Jackline J Yalwala Santos S Abuom David D Ogutu Bernhards B Cowden Jessica J Akala Hoseah M HM Kamau Edwin E

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 20230201 4

<h4>Background</h4>Assessing the infectious reservoir is critical in malaria control and elimination strategies. We conducted a longitudinal epidemiological study in a high-malaria-burden region in Kenya to characterize transmission in an asymptomatic population.<h4>Methods</h4>488 study participants encompassing all ages in 120 households within 30 clusters were followed for 1 year with monthly sampling. Malaria was diagnosed by microscopy and molecular methods. Transmission potential in gameto ...[more]

PMID: 35767269

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