Asymptomatic malaria in selected rural health facilities in Vihiga County, Western Kenya

Year 2025, Volume: 8 Issue: 3, 411 - 417, 30.05.2025

John Khamala Ongonda , Cyrus Ayieko , Elly Ochieng Munde Stephen Miheso

https://doi.org/10.32322/jhsm.1622951

Abstract

Abstract
Background and aims: Malaria is still a devastating health challenge in the world. In 2022, Africa accounted for 93.6% of all malaria cases with 95.4% deaths globally. Kenya recorded about 3.5 million new malaria cases with a mortality of 12,011 deaths while Vihiga County had a prevalence of 20% for all symptomatic outpatients. Asymptomatic malaria infection in Kenya was reported as 42% and 10% from two malaria endemic areas. Asymptomatic patients never visit health facilities for treatment but remain Plasmodium falciparum reservoirs in the community. This study assessed the occurrence of asymptomatic malaria around five rural health facilities in a malaria endemic Vihiga County, Western Kenya.

Methods: This was a cross-sectional survey targeting 336 participants and running between April 2022 and March 2023. CareStart Malaria HRP2 (Pf) was used for sample diagnosis as per manufacturer’s instructions. Demographic and other laboratory parameters of study participants were taken.
Results: Chi-square was used to analyse this data. Average percentage prevalence for asymptomatic malaria was 8.3%; (95% CI; 5.3%-10.8%, P<0.05). Age category of below five years had a prevalence of 2.5% (95% CI: 0.6%-9.5%, P>0.05), between five and seventeen years was 10.6% (95% CI: 5.8%-15.2%, P<0.05) and above seventeen years was 9,6% (95% CI: 4.7%-14.6%, P<0.05). Females had a prevalence of 9.6% (95% CI: 5.5%-13.7%, P<0.05) while males had 6.9% (95% CI: 3.5%-11.0%, P<0.05). High quarterly rainfall of 249.7 mm had 12.2% prevalence while low rainfall of 12 mm had 1.2% prevalence of asymptomatic malaria respectively
Conclusion: This study demonstrated the presence of asymptomatic malaria participants in Vihiga County, Western Kenya. There were more asymptomatic cases during rainy than dry seasons. This study underscores the need for continued surveillance and treatment of the malaria asymptomatic cases to reduce its spread.

Key words: Malaria, asymptomatic malaria, mRDT, Pfhrp2/3

Keywords

Malaria , Asymptomatic malaria , malaria rapid diagnostic test , Pfhrp2/3

Project Number

1

Asymptomatic malaria in selected rural health facilities in Vihiga County, Western Kenya

Abstract

Aims: Malaria is still a devastating health challenge in the world. In 2022, Africa accounted for 93.6% of all malaria cases with 95.4% deaths globally. Kenya recorded about 3.5 million new malaria cases with a mortality of 12,011 deaths while Vihiga County had a prevalence of 20% for all symptomatic outpatients. Asymptomatic malaria infection in Kenya was reported as 42% and 10% from two malaria endemic areas. Asymptomatic patients never visit health facilities for treatment but remain Plasmodium falciparum reservoirs in the community. This study assessed the occurrence of asymptomatic malaria around five rural health facilities in a malaria endemic Vihiga County, Western Kenya.
Methods: This was a cross-sectional survey targeting 336 participants and running between April 2022 and March 2023. CareStart malaria HRP2 (Pf) was used for sample diagnosis as per manufacturer’s instructions. Demographic and other laboratory parameters of study participants were taken.
Results: Chi-square was used to analyse this data. Average percentage prevalence for asymptomatic malaria was 8.3%; (95% CI; 5.3%-10.8%, p<0.05). Age category of below five years had a prevalence of 2.5% (95% CI: 0.6%-9.5%, p>0.05), between five and seventeen years was 10.6% (95% CI: 5.8%-15.2%, p<0.05) and above seventeen years was 9,6% (95% CI: 4.7%-14.6%, p<0.05). Females had a prevalence of 9.6% (95% CI: 5.5%-13.7%, p<0.05) while males had 6.9% (95% CI: 3.5%-11.0%, p<0.05). High quarterly rainfall of 249.7 mm had 12.2% prevalence while low rainfall of 12 mm had 1.2% prevalence of asymptomatic malaria respectively
Conclusion: This study demonstrated the presence of asymptomatic malaria participants in Vihiga County, Western Kenya. There were more asymptomatic cases during rainy than dry seasons. This study underscores the need for continued surveillance and treatment of the malaria asymptomatic cases to reduce its spread.

Keywords

Malaria , asymptomatic malaria , mRDT , Pfhrp2/3

Ethical Statement

Ethical Statement The study was initiated with the approval of the Maseno University Scientific and Ethics Review committee (6th June 2022, No: MUSERC/01047/22) and National commission for science, technology and Innovation, Kenya (1st July 2022 No: NACOSTI/P/22/18417) and oobtaining written consent to participate in the study from the participants

Supporting Institution

This study is supported by Maseno University and the Kenya Medical Research Institute (KEMRI) Kisumu

Project Number

1

Thanks

Thanks

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