RESUMO
BACKGROUND: The RTS,S/AS01E (RTS,S) malaria vaccine is recommended for children in malaria endemic areas. This phase 2b trial evaluates RTS,S fractional- and full-dose regimens in Ghana and Kenya. METHODS: In total, 1500 children aged 5-17 months were randomized (1:1:1:1:1) to receive RTS,S or rabies control vaccine. RTS,S groups received 2 full RTS,S doses at months 0 and 1 and either full (groups R012-20, R012-14-26) or fractional doses (one-fifth; groups Fx012-14-26, Fx017-20-32). RESULTS: At month 32 post-dose 1, vaccine efficacy against clinical malaria (all episodes) ranged from 38% (R012-20; 95% confidence interval [CI]: 24%-49%) to 53% (R012-14-26; 95% CI: 42%-62%). Vaccine impact (cumulative number of cases averted/1000 children vaccinated) was 1344 (R012-20), 2450 (R012-14-26), 2273 (Fx012-14-26), and 2112 (Fx017-20-32). To account for differences in vaccine volume (fractional vs full dose; post hoc analysis), we estimated cases averted/1000 RTS,S full-dose equivalents: 336 (R012-20), 490 (R012-14-26), 874 (Fx012-14-26), and 880 (Fx017-20-32). CONCLUSIONS: Vaccine efficacy was similar across RTS,S groups. Vaccine impact accounting for full-dose equivalence suggests that using fractional-dose regimens could be a viable dose-sparing strategy. If maintained through trial end, these observations underscore the means to reduce cost per regimen thus maximizing impact and optimizing supply. CLINICAL TRIALS REGISTRATION: NCT03276962 (ClinicalTrials.gov).
Assuntos
Vacinas Antimaláricas , Malária Falciparum , Eficácia de Vacinas , Humanos , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/imunologia , Gana , Lactente , Quênia , Feminino , Masculino , Malária Falciparum/prevenção & controle , Malária Falciparum/epidemiologia , Esquemas de Imunização , Malária/prevenção & controle , Plasmodium falciparum/imunologiaRESUMO
BACKGROUND: This study sought to understand community health workers' (CHW) knowledge and perceptions of community beliefs surrounding neonatal jaundice (NNJ), a treatable but potentially fatal condition prevalent in sub-Saharan Africa. METHODS: In this cross-sectional qualitative study, CHWs in Kumasi, Ghana, completed in-depth interviews with trained research assistants using a semi-structured interview guide. Interviews were audiotaped, transcribed verbatim, and analyzed using grounded theory methodology. RESULTS: Knowledge of NNJ varied widely among the 23 respondents: 74% knew NNJ could cause death, 57% knew how to screen for NNJ. 35% of CHWs favored home treatment (sunlight therapy or watchful waiting). Three main themes emerged: CHWs perceived that caregivers prefer home treatment, equating hospital care with death; sunlight and herbs are the most common home treatments; and caregivers attribute NNJ to supernatural causes, delaying jaundice diagnosis. INTERPRETATION: Incomplete understanding of NNJ among trained CHWs and local communities will require improved education among both groups to improve outcomes.