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Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

Hollm-Delgado MG, Piel FB, Weiss DJ, Howes RE, Stuart EA, Hay SI, Black RE - Elife (2015)

Bottom Line: Bacille Calmette Guerin-vaccinated children were more likely to be PfHRP-2 positive (relative risk [RR]=4.06, 95% confidence interval [CI]=2.00-8.28).Measles and polio vaccination were not associated with malaria.Future studies focusing on climate seasonality, placental malaria and HIV are needed to characterize better the association between vitamin A and malaria infection in different settings.

View Article: PubMed Central - PubMed

Affiliation: Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, United States.

ABSTRACT
Recent studies, partly based on murine models, suggest childhood immunization and vitamin A supplements may confer protection against malaria infection, although strong evidence to support these theories in humans has so far been lacking. We analyzed national survey data from children aged 6-59 months in four sub-Saharan African countries over an 18-month time period, to determine the risk of Plasmodium spp. parasitemia (n=8390) and Plasmodium falciparum HRP-2 (PfHRP-2)-related antigenemia (n=6121) following vitamin A supplementation and standard vaccination. Bacille Calmette Guerin-vaccinated children were more likely to be PfHRP-2 positive (relative risk [RR]=4.06, 95% confidence interval [CI]=2.00-8.28). No association was identified with parasitemia. Measles and polio vaccination were not associated with malaria. Children receiving vitamin A were less likely to present with parasitemia (RR=0.46, 95% CI=0.39-0.54) and antigenemia (RR=0.23, 95% CI=0.17-0.29). Future studies focusing on climate seasonality, placental malaria and HIV are needed to characterize better the association between vitamin A and malaria infection in different settings.

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Adjusted relative risk of malaria infection according to differentfeatures of vitamin A supplementation and BCG vaccination(Liu et al., 2012; World Health Organization, 2012).(A) Adjusted for the following factors: age, gender, wealthindex score, mother's highest level of education, malaria treatment duringprevious week, ownership of bed net, proportion of household members under 5years using bed net during previous night, indoor household insecticidespraying, mother's access to antenatal care during last pregnancy, mother'sknowledge regarding vertical HIV transmission, malaria transmission season,and type of community setting (urban vs rural). (B) Covariates‘Age at vaccination’ and ‘Time sincevaccination’ treated as continuous terms when testing for effectmodification in the model. (C) Seasonality only available forchildren vaccinated in 2010 or 2011 calendar year.DOI:http://dx.doi.org/10.7554/eLife.03925.006
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fig2: Adjusted relative risk of malaria infection according to differentfeatures of vitamin A supplementation and BCG vaccination(Liu et al., 2012; World Health Organization, 2012).(A) Adjusted for the following factors: age, gender, wealthindex score, mother's highest level of education, malaria treatment duringprevious week, ownership of bed net, proportion of household members under 5years using bed net during previous night, indoor household insecticidespraying, mother's access to antenatal care during last pregnancy, mother'sknowledge regarding vertical HIV transmission, malaria transmission season,and type of community setting (urban vs rural). (B) Covariates‘Age at vaccination’ and ‘Time sincevaccination’ treated as continuous terms when testing for effectmodification in the model. (C) Seasonality only available forchildren vaccinated in 2010 or 2011 calendar year.DOI:http://dx.doi.org/10.7554/eLife.03925.006

Mentions: Table 2 shows that while BCG vaccination wasnot associated with Plasmodium parasitemia, it was linked to anincreased risk of PƒHRP-2 antigenemia. This effect remainedafter controlling for patient characteristics associated with BCG use in the inverseprobability weighted (IPW) model. DTP was associated with a lower risk ofPlasmodium parasitemia and PƒHRP-2, butonly in the weighted models. Measles and poliomyelitis vaccination were notassociated with malaria antigenemia or parasitemia. Figure 2A shows that the strength of associations between BCG andantigenemia were greater if children were vaccinated during the wet season, amongyounger children and the more time passed since vaccination.10.7554/eLife.03925.005Table 2.


Vitamin A supplements, routine immunization, and the subsequent risk of Plasmodium infection among children under 5 years in sub-Saharan Africa.

Hollm-Delgado MG, Piel FB, Weiss DJ, Howes RE, Stuart EA, Hay SI, Black RE - Elife (2015)

Adjusted relative risk of malaria infection according to differentfeatures of vitamin A supplementation and BCG vaccination(Liu et al., 2012; World Health Organization, 2012).(A) Adjusted for the following factors: age, gender, wealthindex score, mother's highest level of education, malaria treatment duringprevious week, ownership of bed net, proportion of household members under 5years using bed net during previous night, indoor household insecticidespraying, mother's access to antenatal care during last pregnancy, mother'sknowledge regarding vertical HIV transmission, malaria transmission season,and type of community setting (urban vs rural). (B) Covariates‘Age at vaccination’ and ‘Time sincevaccination’ treated as continuous terms when testing for effectmodification in the model. (C) Seasonality only available forchildren vaccinated in 2010 or 2011 calendar year.DOI:http://dx.doi.org/10.7554/eLife.03925.006
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383226&req=5

fig2: Adjusted relative risk of malaria infection according to differentfeatures of vitamin A supplementation and BCG vaccination(Liu et al., 2012; World Health Organization, 2012).(A) Adjusted for the following factors: age, gender, wealthindex score, mother's highest level of education, malaria treatment duringprevious week, ownership of bed net, proportion of household members under 5years using bed net during previous night, indoor household insecticidespraying, mother's access to antenatal care during last pregnancy, mother'sknowledge regarding vertical HIV transmission, malaria transmission season,and type of community setting (urban vs rural). (B) Covariates‘Age at vaccination’ and ‘Time sincevaccination’ treated as continuous terms when testing for effectmodification in the model. (C) Seasonality only available forchildren vaccinated in 2010 or 2011 calendar year.DOI:http://dx.doi.org/10.7554/eLife.03925.006
Mentions: Table 2 shows that while BCG vaccination wasnot associated with Plasmodium parasitemia, it was linked to anincreased risk of PƒHRP-2 antigenemia. This effect remainedafter controlling for patient characteristics associated with BCG use in the inverseprobability weighted (IPW) model. DTP was associated with a lower risk ofPlasmodium parasitemia and PƒHRP-2, butonly in the weighted models. Measles and poliomyelitis vaccination were notassociated with malaria antigenemia or parasitemia. Figure 2A shows that the strength of associations between BCG andantigenemia were greater if children were vaccinated during the wet season, amongyounger children and the more time passed since vaccination.10.7554/eLife.03925.005Table 2.

Bottom Line: Bacille Calmette Guerin-vaccinated children were more likely to be PfHRP-2 positive (relative risk [RR]=4.06, 95% confidence interval [CI]=2.00-8.28).Measles and polio vaccination were not associated with malaria.Future studies focusing on climate seasonality, placental malaria and HIV are needed to characterize better the association between vitamin A and malaria infection in different settings.

View Article: PubMed Central - PubMed

Affiliation: Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, United States.

ABSTRACT
Recent studies, partly based on murine models, suggest childhood immunization and vitamin A supplements may confer protection against malaria infection, although strong evidence to support these theories in humans has so far been lacking. We analyzed national survey data from children aged 6-59 months in four sub-Saharan African countries over an 18-month time period, to determine the risk of Plasmodium spp. parasitemia (n=8390) and Plasmodium falciparum HRP-2 (PfHRP-2)-related antigenemia (n=6121) following vitamin A supplementation and standard vaccination. Bacille Calmette Guerin-vaccinated children were more likely to be PfHRP-2 positive (relative risk [RR]=4.06, 95% confidence interval [CI]=2.00-8.28). No association was identified with parasitemia. Measles and polio vaccination were not associated with malaria. Children receiving vitamin A were less likely to present with parasitemia (RR=0.46, 95% CI=0.39-0.54) and antigenemia (RR=0.23, 95% CI=0.17-0.29). Future studies focusing on climate seasonality, placental malaria and HIV are needed to characterize better the association between vitamin A and malaria infection in different settings.

Show MeSH
Related in: MedlinePlus