Limits...
School-Age Children Are a Reservoir of Malaria Infection in Malawi.

Walldorf JA, Cohee LM, Coalson JE, Bauleni A, Nkanaunena K, Kapito-Tembo A, Seydel KB, Ali D, Mathanga D, Taylor TE, Valim C, Laufer MK - PLoS ONE (2015)

Bottom Line: Participants aged 6-15 years were at higher risk of infection (OR=4.8; 95%CI, 4.0-5.8) and asymptomatic infection (OR=4.2; 95%CI, 2.7-6.6) than younger children in all settings.School-age children used bednets less frequently than other age groups.Compared to young children, school-age children were brought less often for treatment and more often to unreliable treatment sources.

View Article: PubMed Central - PubMed

Affiliation: Center for Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America.

ABSTRACT

Unlabelled: Malaria surveillance and interventions in endemic countries often target young children at highest risk of malaria morbidity and mortality. We aimed to determine whether school-age children and adults not captured in surveillance serve as a reservoir for malaria infection and may contribute to malaria transmission. Cross-sectional surveys were conducted in one rainy and one dry season in southern Malawi. Demographic and health information was collected for all household members. Blood samples were obtained for microscopic and PCR identification of Plasmodium falciparum. Among 5796 individuals aged greater than six months, PCR prevalence of malaria infection was 5%, 10%, and 20% in dry, and 9%, 15%, and 32% in rainy seasons in Blantyre, Thyolo, and Chikhwawa, respectively. Over 88% of those infected were asymptomatic. Participants aged 6-15 years were at higher risk of infection (OR=4.8; 95%CI, 4.0-5.8) and asymptomatic infection (OR=4.2; 95%CI, 2.7-6.6) than younger children in all settings. School-age children used bednets less frequently than other age groups. Compared to young children, school-age children were brought less often for treatment and more often to unreliable treatment sources.

Conclusion: School-age children represent an underappreciated reservoir of malaria infection and have less exposure to antimalarial interventions. Malaria control and elimination strategies may need to expand to include this age group.

No MeSH data available.


Related in: MedlinePlus

Asymptomatic infections among malaria-infected individuals by season and district (A) and by age group (B).Asymptomatic malaria was defined as PCR positive, with temperature <37.5°C and without reported fever within 48 hours. Prevalence differences were comparable (and Pearson chi-square P values >0.05) across districts in dry and rainy seasons and between seasons. In 2B, the odds of asymptomatic infection by age group were adjusted for season and sex and were statistically significant in Chikhwawa and Thyolo but not in Blantyre (Pinteraction age and district = 0.001).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4514805&req=5

pone.0134061.g002: Asymptomatic infections among malaria-infected individuals by season and district (A) and by age group (B).Asymptomatic malaria was defined as PCR positive, with temperature <37.5°C and without reported fever within 48 hours. Prevalence differences were comparable (and Pearson chi-square P values >0.05) across districts in dry and rainy seasons and between seasons. In 2B, the odds of asymptomatic infection by age group were adjusted for season and sex and were statistically significant in Chikhwawa and Thyolo but not in Blantyre (Pinteraction age and district = 0.001).

Mentions: Almost all infected individuals were asymptomatic; the proportion of asymptomatic infections among infected individuals was similar across seasons (P = 0.88) and districts (P = 0.59) (Fig 2A). Among malaria-infected participants, school-age children and adults had a four-fold increased odds of asymptomatic infection compared to younger children respectively after adjustment for potential confounders (Fig 2B). These differences in odds by age group varied by district (Page-district-interaction = 0.001), and were not observed in Blantyre. Males had twice the odds of asymptomatic infection as females (OR = 1.9; 95%CI, 1.4–2.8). The association of age and likelihood of asymptomatic infection among those infected was not affected by other socioeconomic variables or net use.


School-Age Children Are a Reservoir of Malaria Infection in Malawi.

Walldorf JA, Cohee LM, Coalson JE, Bauleni A, Nkanaunena K, Kapito-Tembo A, Seydel KB, Ali D, Mathanga D, Taylor TE, Valim C, Laufer MK - PLoS ONE (2015)

Asymptomatic infections among malaria-infected individuals by season and district (A) and by age group (B).Asymptomatic malaria was defined as PCR positive, with temperature <37.5°C and without reported fever within 48 hours. Prevalence differences were comparable (and Pearson chi-square P values >0.05) across districts in dry and rainy seasons and between seasons. In 2B, the odds of asymptomatic infection by age group were adjusted for season and sex and were statistically significant in Chikhwawa and Thyolo but not in Blantyre (Pinteraction age and district = 0.001).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4514805&req=5

pone.0134061.g002: Asymptomatic infections among malaria-infected individuals by season and district (A) and by age group (B).Asymptomatic malaria was defined as PCR positive, with temperature <37.5°C and without reported fever within 48 hours. Prevalence differences were comparable (and Pearson chi-square P values >0.05) across districts in dry and rainy seasons and between seasons. In 2B, the odds of asymptomatic infection by age group were adjusted for season and sex and were statistically significant in Chikhwawa and Thyolo but not in Blantyre (Pinteraction age and district = 0.001).
Mentions: Almost all infected individuals were asymptomatic; the proportion of asymptomatic infections among infected individuals was similar across seasons (P = 0.88) and districts (P = 0.59) (Fig 2A). Among malaria-infected participants, school-age children and adults had a four-fold increased odds of asymptomatic infection compared to younger children respectively after adjustment for potential confounders (Fig 2B). These differences in odds by age group varied by district (Page-district-interaction = 0.001), and were not observed in Blantyre. Males had twice the odds of asymptomatic infection as females (OR = 1.9; 95%CI, 1.4–2.8). The association of age and likelihood of asymptomatic infection among those infected was not affected by other socioeconomic variables or net use.

Bottom Line: Participants aged 6-15 years were at higher risk of infection (OR=4.8; 95%CI, 4.0-5.8) and asymptomatic infection (OR=4.2; 95%CI, 2.7-6.6) than younger children in all settings.School-age children used bednets less frequently than other age groups.Compared to young children, school-age children were brought less often for treatment and more often to unreliable treatment sources.

View Article: PubMed Central - PubMed

Affiliation: Center for Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America.

ABSTRACT

Unlabelled: Malaria surveillance and interventions in endemic countries often target young children at highest risk of malaria morbidity and mortality. We aimed to determine whether school-age children and adults not captured in surveillance serve as a reservoir for malaria infection and may contribute to malaria transmission. Cross-sectional surveys were conducted in one rainy and one dry season in southern Malawi. Demographic and health information was collected for all household members. Blood samples were obtained for microscopic and PCR identification of Plasmodium falciparum. Among 5796 individuals aged greater than six months, PCR prevalence of malaria infection was 5%, 10%, and 20% in dry, and 9%, 15%, and 32% in rainy seasons in Blantyre, Thyolo, and Chikhwawa, respectively. Over 88% of those infected were asymptomatic. Participants aged 6-15 years were at higher risk of infection (OR=4.8; 95%CI, 4.0-5.8) and asymptomatic infection (OR=4.2; 95%CI, 2.7-6.6) than younger children in all settings. School-age children used bednets less frequently than other age groups. Compared to young children, school-age children were brought less often for treatment and more often to unreliable treatment sources.

Conclusion: School-age children represent an underappreciated reservoir of malaria infection and have less exposure to antimalarial interventions. Malaria control and elimination strategies may need to expand to include this age group.

No MeSH data available.


Related in: MedlinePlus