Publications

@article{Cairns2022,

title = {The duration of protection against clinical malaria provided by the combination of seasonal RTS,S/AS01E vaccination and seasonal malaria chemoprevention versus either intervention given alone},

author = {Matthew Cairns and Amadou Barry and Issaka Zongo and Issaka Sagara and Serge R. Yerbanga and Modibo Diarra and Charles Zoungrana and Djibrilla Issiaka and Abdoul Aziz Sienou and Amadou Tapily and Koualy Sanogo and Mahamadou Kaya and Seydou Traore and Kalifa Diarra and Hama Yalcouye and Youssoufa Sidibe and Alassane Haro and Ismaila Thera and Paul Snell and Jane Grant and Halidou Tinto and Paul Milligan and Daniel Chandramohan and Brian Greenwood and Alassane Dicko and Jean Bosco Ouedraogo},

url = {https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-022-02536-5},

doi = {10.1186/s12916-022-02536-5},

issn = {1741-7015},

year  = {2022},

date = {2022-01-01},

journal = {BMC Medicine},

volume = {20},

issue = {1},

pages = {352},

abstract = {BACKGROUND A recent trial of 5920 children in Burkina Faso and Mali showed that the combination of seasonal vaccination with the RTS,S/AS01E malaria vaccine (primary series and two seasonal boosters) and seasonal malaria chemoprevention (four monthly cycles per year) was markedly more effective than either intervention given alone in preventing clinical malaria, severe malaria, and deaths from malaria. METHODS In order to help optimise the timing of these two interventions, trial data were reanalysed to estimate the duration of protection against clinical malaria provided by RTS,S/AS01E when deployed seasonally, by comparing the group who received the combination of SMC and RTS,S/AS01E with the group who received SMC alone. The duration of protection from SMC was also estimated comparing the combined intervention group with the group who received RTS,S/AS01E alone. Three methods were used: Piecewise Cox regression, Flexible parametric survival models and Smoothed Schoenfeld residuals from Cox models, stratifying on the study area and using robust standard errors to control for within-child clustering of multiple episodes. RESULTS The overall protective efficacy from RTS,S/AS01E over 6 months was at least 60% following the primary series and the two seasonal booster doses and remained at a high level over the full malaria transmission season. Beyond 6 months, protective efficacy appeared to wane more rapidly, but the uncertainty around the estimates increases due to the lower number of cases during this period (coinciding with the onset of the dry season). Protection from SMC exceeded 90% in the first 2-3 weeks post-administration after several cycles, but was not 100%, even immediately post-administration. Efficacy begins to decline from approximately day 21 and then declines more sharply after day 28, indicating the importance of preserving the delivery interval for SMC cycles at a maximum of four weeks. CONCLUSIONS The efficacy of both interventions was highest immediately post-administration. Understanding differences between these interventions in their peak efficacy and how rapidly efficacy declines over time will help to optimise the scheduling of SMC, malaria vaccination and the combination in areas of seasonal transmission with differing epidemiology, and using different vaccine delivery systems. TRIAL REGISTRATION The RTS,S-SMC trial in which these data were collected was registered at clinicaltrials.gov: NCT03143218.},

keywords = {Malaria, Malaria vaccination, Plasmodium falciparum, RTS, S/AS01E, seasonal malaria chemoprevention},

pubstate = {published},

tppubtype = {article}

}

@article{Phiri2021-oy,

title = {The duration of protection from azithromycin against malaria,  acute respiratory, gastrointestinal, and skin infections when  given alongside seasonal malaria chemoprevention: Secondary  analyses of data from a clinical trial in hound\'{e}, Burkina  Faso, and bougouni, Mali},

author = {Mphatso Dennis Phiri and Matthew Cairns and Issaka Zongo and Frederic Nikiema and Modibo Diarra and Rakiswend\'{e} Serge Yerbanga and Amadou Barry and Amadou Tapily and Samba Coumare and Ismaila Thera and Irene Kuepfer and Paul Milligan and Halidou Tinto and Alassane Dicko and Jean Bosco Ou\'{e}draogo and Brian Greenwood and Daniel Chandramohan and Issaka Sagara},

doi = {10.1093/cid/ciaa1905},

issn = {1537-6591 1058-4838},

year  = {2021},

date = {2021-10-01},

urldate = {2021-10-01},

journal = {Clin. Infect. Dis.},

volume = {73},

number = {7},

pages = {e2379--e2386},

publisher = {Oxford University Press (OUP)},

abstract = {BACKGROUND: Mass drug administration (MDA) with azithromycin 

 (AZ) is being considered as a strategy to promote child survival 

 in sub-Saharan Africa, but the mechanism by which AZ reduces 

 mortality is unclear. To better understand the nature and extent 

 of protection provided by AZ, we explored the profile of 

 protection by time since administration, using data from a 

 household-randomized, placebo-controlled trial in Burkina Faso 

 and Mali. METHODS: Between 2014 and 2016, 30 977 children aged 

 3-59 months received seasonal malaria chemoprevention (SMC) with 

 sulfadoxine-pyrimethamine plus amodiaquine and either AZ or 

 placebo monthly, on 4 occasions each year. Poisson regression 

 with gamma-distributed random effects, accounting for the 

 household randomization and within-individual clustering of 

 illness episodes, was used to compare incidence of prespecified 

 outcomes between SMC+AZ versus SMC+placebo groups in fixed time 

 strata post-treatment. The likelihood ratio test was used to 

 assess evidence for a time-treatment group interaction. RESULTS: 

 Relative to SMC+placebo, there was no evidence of protection 

 from SMC+AZ against hospital admissions and deaths. Additional 

 protection from SMC+AZ against malaria was confined to the first 

 2 weeks post-administration (protective efficacy (PE): 24.2% 

 [95% CI: 17.8%, 30.1%]). Gastroenteritis and pneumonia were 

 reduced by 29.9% [21.7; 37.3%], and 34.3% [14.9; 49.3%], 

 respectively, in the first 2 weeks postadministration. 

 Protection against nonmalaria fevers with a skin condition 

 persisted up to 28 days: PE: 46.3% [35.1; 55.6%]. CONCLUSIONS: 

 The benefits of AZ-MDA are broad-ranging but short-lived. To 

 maximize impact, timing of AZ-MDA must address the challenge of 

 targeting asynchronous morbidity and mortality peaks from 

 different causes.},

note = {© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.

PMID: 33417683 

PMCID: PMC8492219},

keywords = {Antimalarials/therapeutic use, Azithromycin, Azithromycin/therapeutic use, Burkina Faso/epidemiology, Chemoprevention, Child, child mortality, Drug Combinations, duration of protection, Humans, Infant, Malaria/drug therapy/epidemiology/prevention \& control, Mali/epidemiology, Preschool, Sahel, seasonal malaria chemoprevention, Seasons},

pubstate = {published},

tppubtype = {article}

}

@article{Yameogo2021-bb,

title = {Effect of seasonal malaria chemoprevention plus azithromycin on  Plasmodium falciparum transmission: gametocyte infectivity and  mosquito fitness},

author = {Koudraogo Bienvenue Yam\'{e}ogo and Rakiswend\'{e} Serge Yerbanga and Seydou Bienvenu Ouattara and Franck A Yao and Thierry Lef`evre and Issaka Zongo and Frederic Niki`ema and Yves Daniel Compaor\'{e} and Halidou Tinto and Daniel Chandramohan and Brian Greenwood and Adrien M G Belem and Anna Cohuet and Jean Bosco Ou\'{e}draogo},

doi = {10.1186/s12936-021-03855-3},

issn = {1475-2875},

year  = {2021},

date = {2021-07-27},

urldate = {2021-07-27},

journal = {Malar. J.},

volume = {20},

number = {1},

pages = {326},

publisher = {Springer Science and Business Media LLC},

abstract = {BACKGROUND: Seasonal malaria chemoprevention (SMC) consists of administration of sulfadoxine-pyrimethamine (SP) + amodiaquine (AQ) at monthly intervals to children  during the malaria transmission period. Whether the addition of azithromycin (AZ) to  SMC could potentiate the benefit of the intervention was tested through a  double-blind, randomized, placebo-controlled trial. The effect of SMC and the  addition of AZ, on malaria transmission and on the life history traits of Anopheles  gambiae mosquitoes have been investigated. METHODS: The study included 438 children  randomly selected from among participants in the SMC + AZ trial and 198 children  from the same area who did not receive chemoprevention. For each participant in the  SMC + AZ trial, blood was collected 14 to 21 days post treatment, examined for the  presence of malaria sexual and asexual stages and provided as a blood meal to An.  gambiae females using a direct membrane-feeding assay. RESULTS: The SMC treatment,  with or without AZ, significantly reduced the prevalence of asexual Plasmodium  falciparum (LRT X(2)(2) = 69, P \< 0.0001) and the gametocyte prevalence (LRT  X(2)(2) = 54, P \< 0.0001). In addition, the proportion of infectious feeds (LRT  X(2)(2) = 61, P \< 0.0001) and the prevalence of oocysts among exposed mosquitoes  (LRT X(2)(2) = 22.8, P \< 0.001) was reduced when mosquitoes were fed on blood from  treated children compared to untreated controls. The addition of AZ to SPAQ was  associated with an increased proportion of infectious feeds (LRT X(2)(1) = 5.2,  P = 0.02), suggesting a significant effect of AZ on gametocyte infectivity. There  was a slight negative effect of SPAQ and SPAQ + AZ on mosquito survival compared to  mosquitoes fed with blood from control children (LRTX(2)(2) = 330, P \< 0.0001).  CONCLUSION: This study demonstrates that SMC may contribute to a reduction in human  to mosquito transmission of P. falciparum, and the reduced mosquito longevity  observed for females fed on treated blood may increase the benefit of this  intervention in control of malaria. The addition of AZ to SPAQ in SMC appeared to  enhance the infectivity of gametocytes providing further evidence that this  combination is not an appropriate intervention.},

note = {© 2021. The Author(s).

PMID: 34315475 

PMCID: PMC8314489},

keywords = {Amodiaquine/administration \& dosage, Animals, Antimalarials/administration \& dosage, Chemoprevention, Child, Culicidae/physiology, Drug Combinations, Falciparum/prevention \& control/transmission, Gametocytes, Genetic Fitness, Humans, Malaria, Plasmodium falciparum/physiology, Preschool, Pyrimethamine/administration \& dosage, seasonal malaria chemoprevention, Seasons, Sulfadoxine/administration \& dosage, Transmission},

pubstate = {published},

tppubtype = {article}

}

@article{De_Wit2021-yi,

title = {Nutritional status in young children prior to the malaria  transmission season in Burkina Faso and Mali, and its impact on  the incidence of clinical malaria},

author = {Mariken Wit and Matthew Cairns and Yves Daniel Compaor\'{e} and Issaka Sagara and Irene Kuepfer and Issaka Zongo and Amadou Barry and Modibo Diarra and Amadou Tapily and Samba Coumare and Ismaila Thera and Frederic Nikiema and R Serge Yerbanga and Rosemonde M Guissou and Halidou Tinto and Alassane Dicko and Daniel Chandramohan and Brian Greenwood and Jean Bosco Ouedraogo},

doi = {10.1186/s12936-021-03802-2},

issn = {1475-2875},

year  = {2021},

date = {2021-06-22},

urldate = {2021-06-22},

journal = {Malar. J.},

volume = {20},

number = {1},

pages = {274},

publisher = {Springer Science and Business Media LLC},

abstract = {BACKGROUND: Malaria and malnutrition remain major problems in 

 Sahel countries, especially in young children. The direct effect 

 of malnutrition on malaria remains poorly understood, and may 

 have important implications for malaria control. In this study, 

 nutritional status and the association between malnutrition and 

 subsequent incidence of symptomatic malaria were examined in 

 children in Burkina Faso and Mali who received either 

 azithromycin or placebo, alongside seasonal malaria 

 chemoprevention. METHODS: Mid-upper arm circumference (MUAC) was 

 measured in all 20,185 children who attended a screening visit 

 prior to the malaria transmission season in 2015. Prior to the 

 2016 malaria season, weight, height and MUAC were measured among 

 4149 randomly selected children. Height-for-age, weight-for-age, 

 weight-for-height, and MUAC-for-age were calculated as 

 indicators of nutritional status. Malaria incidence was measured 

 during the following rainy seasons. Multivariable random effects 

 Poisson models were created for each nutritional indicator to 

 study the effect of malnutrition on clinical malaria incidence 

 for each country. RESULTS: In both 2015 and 2016, nutritional 

 status prior to the malaria season was poor. The most prevalent 

 form of malnutrition in Burkina Faso was being underweight 

 (30.5%; 95% CI 28.6-32.6), whereas in Mali stunting was most 

 prevalent (27.5%; 95% CI 25.6-29.5). In 2016, clinical malaria 

 incidence was 675 per 1000 person-years (95% CI 613-744) in 

 Burkina Faso, and 1245 per 1000 person-years (95% CI 1152-1347) 

 in Mali. There was some evidence that severe stunting was 

 associated with lower incidence of malaria in Mali (RR 0.81; 95% CI 0.64-1.02; p = 0.08), but this association was not seen 

 in Burkina Faso. Being moderately underweight tended to be 

 associated with higher incidence of clinical malaria in Burkina Faso (RR 1.27; 95% CI 0.98-1.64; p = 0.07), while this was the 

 case in Mali for moderate wasting (RR 1.27; 95% CI 0.98-1.64; p = 0.07). However, these associations were not observed in 

 severely affected children, nor consistent between countries. 

 MUAC-for-age was not associated with malaria risk. CONCLUSIONS: 

 Both malnutrition and malaria were common in the study areas, 

 high despite high coverage of seasonal malaria chemoprevention 

 and long-lasting insecticidal nets. However, no strong or 

 consistent evidence was found for an association between any of 

 the nutritional indicators and the subsequent incidence of 

 clinical malaria.},

note = {PMID: 34158054 

PMCID: PMC8220741},

keywords = {Acute malnutrition, Antimalarials/administration \& dosage, Azithromycin/administration \& dosage, Burkina Faso, Burkina Faso/epidemiology, Child, Chronic malnutrition, Female, Humans, Incidence, Infant, Malaria, Malaria/epidemiology/transmission, Male, Nutritional Status, Preschool, seasonal malaria chemoprevention, Seasons},

pubstate = {published},

tppubtype = {article}

}