Objective
Half the world's population uses biomass fuel for their daily needs but the resultant emissions and indoor air pollution (IAP) are harmful to health. So far, evidence for a link between IAP ...and tuberculosis (TB) was insufficient. We report an updated systematic review due to recent increase in the evidence and growing interest in testing interventions.
Methods
Systematic search of PubMed (including Medline), CAB s (through Ovid SP) and Web of Knowledge using the following search terms: ‘IAP or biomass or cooking smoke’ and ‘TB’. 452 s were reviewed, and only 12 articles were deemed to be reporting the effects of IAP on TB and were taken forward to full review, and one study was added through hand search of references. Data on measures of effect of IAP on TB were extracted, and meta‐analysis was carried out to estimate pooled measures of effect.
Results
Thirteen studies have reported investigating association between IAP and TB since 1996. TB cases are more likely to be exposed to IAP than healthy controls (pooled OR 1.30; 95% CI, 1.04–1.62; P = 0.02).
Conclusions
There is increasingly strong evidence for an association between IAP and TB. Further studies are needed to understand the burden of TB attributable to IAP. Interventions such as clean cook stoves to reduce the adverse effects of IAP merit rigorous evaluation, particularly in Africa and India where the prevalence of IAP and TB is high.
ObjectifLa moitié de la population mondiale utilise du combustible à base de biomasse pour leurs besoins quotidiens, mais les émissions qui en résultent et la pollution de l'air intérieur sont nocives pour la santé. Jusqu’à présent, la preuve d'un lien entre la pollution de l'air intérieur et la tuberculose était insuffisante. Nous rapportons une analyse systématique mise à jour suite à l'augmentation récente des preuves et de l'intérêt croissant des interventions pour la mesure de ce lien.MéthodesRecherche systématique dans PubMed (Medline y compris), résumés CAB (sur Ovide SP), et ‘Web of Knowledge’, en utilisant les termes de recherche suivants: «pollution de l'air intérieur ou biomasse ou fumée de cuisson» et «tuberculose ou TB». 452 résumés ont été examinés et seuls 12 articles considérés comme rapportant sur les effets de la pollution de l'air intérieur sur la tuberculose ont été utilisés pour une analyse complète. Une étude a été ajoutée suite à la recherche manuelle de références. Les données sur les mesures de l'effet de la pollution de l'air intérieur sur la tuberculose ont été extraites et la méta‐analyse a été effectuée pour évaluer les mesures poolées de l'effet.RésultatsTreize études rapportaient sur des études sur l'association entre la pollution de l'air intérieur et la tuberculose depuis 1996. Les cas de tuberculose sont plus susceptibles d’être exposés à la pollution de l'air intérieur que les témoins sains (OR poolés: 1,30; IC95%: 1,04 à 1,62; P = 0,02).ConclusionsIl y a de plus en plus de preuves solides d'une association entre la pollution de l'air intérieur et la tuberculose. Des études supplémentaires sont nécessaires pour comprendre la charge de morbidité de la tuberculose attribuable à la pollution de l'air intérieur. Des interventions telles que celles utilisant des cuisinières propres pour réduire les effets néfastes de la pollution de l'air intérieur méritent une rigoureuse évaluation, en particulier en Afrique et en Inde où la prévalence de la pollution de l'air intérieur et de la tuberculose est élevée.
ObjetivoLa mitad de la población mundial utiliza la biomasa como combustible para cubrir sus necesidades diarias, pero las emisiones resultantes y la contaminación intradomiciliaria (CID) son dañinas para la salud. Hasta ahora, la evidencia que relacionaba la CID y la TB era insuficiente. Aquí reportamos una revisión sistemática y puesta al día, debido al aumento de evidencia y al creciente interés en realizar una evaluación de las intervenciones.MétodosBúsqueda sistemática en PubMed (incluido Medline); s CAB (a través de Ovid SP); y Web of Knowledge, utilizando los siguientes términos de búsqueda: ‘contaminación aire intradomiciliario o biomasa o humo de cocinas’ 12 artículos y ‘tuberculosis o TB’. Se revisaron 452 resúmenes y de los cuales se consideró que solo reportaban los efectos de la CID sobre la TB y se les realizó una revisión completa. Un otro estudio se añadió tras una búsqueda manual de las referencias. Se extrajeron datos sobre medidas del efecto de la PID sobre la TB y se realizó un meta‐análisis para calcular una medida unificada del efecto.ResultadosTrece estudios han reportado investigar la asociación entre el CID y la TB desde 1996. Los casos de TB tienen mayor probabilidad de exposición a la CID que los controles sanos (OR unificado 1.30; IC 95%: 1.04–1.62, P = 0.02).ConclusiónExiste una evidencia cada vez mayor de la asociación entre la contaminación del aire intradomiciliario y la TB. Se requieren más estudios para entender la carga de TB atribuible a la CID. Intervenciones, tales como las cocinas limpias, que reduzcan los efectos adversos de la CID, merecen una evaluación rigurosa, particularmente en África e India en donde la prevalencia de la CID y la TB son altas.
Pay for Performance (P4P) mechanisms to health facilities and providers are currently being tested in several low- and middle-income countries (LMIC) to improve maternal and child health (MCH). This ...paper reviews the existing evidence on the effect of P4P program on quality of MCH care in LMICs.
A systematic review of literature was conducted according to a registered protocol. MEDLINE, Web of Science, and Embase were searched using the key words maternal care, quality of care, ante natal care, emergency obstetric and neonatal care (EmONC) and child care. Of 4535 records retrieved, only eight papers met the inclusion criteria. Primary outcome of interest was quality of MCH disaggregated into structural quality, process quality and outcomes. Risk of bias across studies was assessed through a customized quality checklist.
There were four controlled before after intervention studies, three cluster randomized controlled trials and one case control with post-intervention comparison of P4P programs for MCH care in Burundi, Democratic Republic of Congo, Egypt, the Philippines, and Rwanda. There is some evidence of positive effect of P4P only on process quality of MCH. The effect of P4P on delivery, EmONC, post natal care and under-five child care were not evaluated in these studies. There is weak evidence for P4P's positive effect on maternal and neonatal health outcomes and out-of-pocket expenses. P4P program had a few negative effects on structural quality.
P4P is effective to improve process quality of ante natal care. However, further research is needed to understand P4P's impact on MCH and their causal pathways in LMICs.
PROSPERO registration number CRD42014013077 .
Verbal autopsy (VA) is a practical method for determining probable causes of death at the population level in places where systems for medical certification of cause of death are weak. VA methods ...suitable for use in routine settings, such as civil registration and vital statistics (CRVS) systems, have developed rapidly in the last decade. These developments have been part of a growing global momentum to strengthen CRVS systems in low-income countries. With this momentum have come pressure for continued research and development of VA methods and the need for a single standard VA instrument on which multiple automated diagnostic methods can be developed.
In 2016, partners harmonized a WHO VA standard instrument that fully incorporates the indicators necessary to run currently available automated diagnostic algorithms. The WHO 2016 VA instrument, together with validated approaches to analyzing VA data, offers countries solutions to improving information about patterns of cause-specific mortality. This VA instrument offers the opportunity to harmonize the automated diagnostic algorithms in the future.
Despite all improvements in design and technology, VA is only recommended where medical certification of cause of death is not possible. The method can nevertheless provide sufficient information to guide public health priorities in communities in which physician certification of deaths is largely unavailable. The WHO 2016 VA instrument, together with validated approaches to analyzing VA data, offers countries solutions to improving information about patterns of cause-specific mortality.
The effectiveness of intermittent preventive treatment of malaria in pregnancy (IPTp) may be compromised by the spread of resistance to sulphadoxine/pyrimethamine (SP) across Africa. But little ...information exists on alternative drugs for IPTp or alternative strategies for the prevention of malaria in pregnancy. Therefore, we have investigated whether screening with a rapid diagnostic test and treatment of those who are positive (IST) at routine antenatal clinic attendances is as effective and as safe as SP-IPTp in pregnant women.
During antenatal clinic sessions in six health facilities in Ghana held between March 2007 and September 2007, 3333 pregnant women who satisfied inclusion criteria were randomised into three intervention arms (1) standard SP-IPTp, (2) IST and treatment with SP or (3) IST and treatment with amodiaquine+artesunate (AQ+AS). All women received a long-lasting insecticide treated net. Study women had a maximum of three scheduled follow-up visits following enrollment. Haemoglobin concentration and peripheral parasitaemia were assessed between 36 and 40 weeks of gestation. Birth weight was measured at delivery or within 72 hours for babies delivered at home. Parasite prevalence at enrollment in primigravidae and in multigravidae was 29.6% and 10.2% respectively. At 36-40 weeks of gestation the prevalence of asymptomatic parasitaemia was 12.1% in study women overall and was very similar in all treatment groups. The risk of third trimester severe anaemia or low birth weight did not differ significantly between the three treatment groups regardless of gravidity. IST with AQ+AS or SP was not inferior to SP-IPTp in reducing the risk of low birth weight (RD = -1.1795%CI; -4.39-1.02 for IST-SP vs. SP-IPTp and RD = 0.7895%CI; -2.11-3.68 for IST-AQAS vs. SP-IPTp); third trimester severe anaemia (RD = 0.2995%CI; -0.69-1.30 for IST-SP vs. SP-IPTp and RD = -0.3695%CI;-1.12-0.44 for IST-AQAS vs. SP-IPTp).
The results of this study suggest that in an area of moderately high malaria transmission, IST with SP or AS+AQ may be a safe and effective strategy for the control of malaria in pregnancy. However, it is important that these encouraging findings are confirmed in other geographical areas and that the impact of IST on placental malaria is investigated.
ClinicalTrials.gov NCT00432367 NCT00432367.
Studies of the association between malaria in pregnancy (MiP) and malaria during infancy have provided mixed results. A systematic review was conducted to evaluate available evidence on the impact of ...Plasmodium falciparum malaria infection during pregnancy, and intermittent preventive treatment of malaria during pregnancy (IPTp), on the risk of clinical malaria or parasitaemia during infancy.
MEDLINE, EMBASE, Global Health, and Malaria in Pregnancy Library databases were searched from inception to 22 May 2018 for articles published in English that reported on associations between MiP and malaria risk in infancy. Search terms included malaria, Plasmodium falciparum, pregnancy, placenta, maternal, prenatal, foetal, newborn, infant, child or offspring or preschool. Randomized controlled trials and prospective cohort studies, which followed infants for at least 6 months, were included if any of the following outcomes were reported: incidence of clinical malaria, prevalence of parasitaemia, and time to first episode of parasitaemia or clinical malaria. Substantial heterogeneity between studies precluded meta-analysis. Thus, a narrative synthesis of included studies was conducted.
The search yielded 14 published studies, 10 prospective cohort studies and four randomized trials; all were conducted in sub-Saharan Africa. Infants born to mothers with parasitaemia during pregnancy were at higher risk of malaria in three of four studies that assessed this association. Placental malaria detected by microscopy or histology was associated with a higher risk of malaria during infancy in nine of 12 studies, but only one study adjusted for malaria transmission intensity. No statistically significant associations between the use of IPTp or different IPTp regimens and the risk of malaria during infancy were identified.
Evidence of an association between MiP and IPTp and risk of malaria in infancy is limited and of variable quality. Most studies did not adequately adjust for malaria transmission intensity shared by mothers and their infants. Further research is needed to confirm or exclude an association between MiP and malaria in infancy. Randomized trials evaluating highly effective interventions aimed at preventing MiP, such as IPTp with dihydroartemisinin-piperaquine, may help to establish a causal association between MiP and malaria in infancy.
The populations of moderate or highly malaria endemic areas gradually acquire some immunity to malaria as a result of repeated exposure to the infection. When this exposure is reduced as a result of ...effective malaria control measures, subjects who benefitted from the intervention may consequently be at increased risk of malaria if the intervention is withdrawn, especially if this is done abruptly, and an effective malaria vector remains. There have been many examples of this occurring in the past, a phenomenon often termed 'rebound malaria', with the incidence of malaria rebounding to the level present before the intervention was introduced. Because the main clinical burden of malaria in areas with a high level of malaria transmission is in young children, malaria control efforts have, in recent decades, focussed on this group, with substantial success being obtained with interventions such as insecticide treated mosquito nets, chemoprevention and, most recently, malaria vaccines. These are interventions whose administration may not be sustained. This has led to concerns that in these circumstances, the overall burden of malaria in children may not be reduced but just delayed, with the main period of risk being in the period shortly after the intervention is no longer given. Although dependent on the same underlying process as classical 'resurgent' malaria, it may be helpful to differentiate the two conditions, describing the later as 'delayed malaria'. In this paper, some of the evidence that delayed malaria occurs is discussed and potential measures for reducing its impact are suggested.
Background. Variation in the risk of malaria within populations is a frequently described but poorly understood phenomenon. This heterogeneity creates opportunities for targeted interventions but ...only if hot spots of malaria transmission can be easily identified. Methods. We determined spatial patterns in malaria transmission in a district in northeastern Tanzania, using malaria incidence data from a cohort study involving infants and household-level mosquito sampling data. The parasite prevalence rates and age-specific seroconversion rates (SCRs) of antibodies against Plasmodium falciparum antigens were determined in samples obtained from people attending health care facilities. Results. Five clusters of higher malaria incidence were detected and interpreted as hot spots of transmission. These hot spots partially overlapped with clusters of higher mosquito exposure but could not be satisfactorily predicted by a probability model based on environmental factors. Small-scale local variation in malaria exposure was detected by parasite prevalence rates and SCR estimates for samples of health care facility attendees. SCR estimates were strongly associated with local malaria incidence rates and predicted hot spots of malaria transmission with 95% sensitivity and 85% specificity. Conclusions. Serological markers were able to detect spatial variation in malaria transmission at the microepidemiological level, and they have the potential to form an effective method for spatial targeting of malaria control efforts.
Intermittent preventive treatment during pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) is used to prevent malaria and associated unfavorable maternal and foetal outcomes in pregnancy in moderate ...to high malaria transmission areas. Effectiveness of IPTp-SP is, however, threatened by mutations in the Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes which confer resistance to pyrimethamine and sulfadoxine, respectively. This study determined the prevalence of molecular markers of SP resistance among pregnant women in a high malaria transmission area in the forest-savannah area of Ghana. Genomic DNA was extracted from 286 P. falciparum-positive dried blood spots obtained from pregnant women aged ≥18 years (255 at first Antenatal Care (ANC) clinic visit and 31 at delivery from 2017 to 2019) using Chelex 100. Mutations in Pfdhfr and Pfdhps genes were detected using molecular inversion probes and next generation sequencing. In the Pfdhfr gene, single nucleotide polymorphisms (SNPs) were detected in 83.1% (157/189), 92.0% (173/188) and 91.0% (171/188) at codons 51, 59, and 108 respectively in samples collected at first ANC visit, while SNPs were detected in 96.6 (28/29), 96.6% (28/29) and 96.8% (30/31) in isolates collected at delivery. The Pfdhfr triple mutant N51I, C59R and S108N (IRN) was carried by 80.5% (128/159) and 96.5% (28/29) of the typed isolates collected at ANC visit and at delivery respectively. In the Pfdhps gene, SNPs were detected in 0.6% (1/174), 76.2% (138/181), 33.2% (60/181), 1.2% (2/174), 0% (0/183), and 16.6% (27/173) at codons 431, 436, 437, 540, 581 and 613 respectively in samples collected at ANC, and 0% (0/25), 72% (18/25), 40% (10/25), 3.6% (1/25), 0% (0/29) and 7.4% (2/27) in samples collected at delivery. Quadruple mutant Pfdhfr N51I, C59R, and S108N + Pfdhps A437G (IRN-GK) was present in 25.8% (33/128) and 34.8% (8/23) of isolates at ANC and at delivery respectively. Quintuple mutant alleles Pfdhfr N51I, C59R, and S108N + Pfdhps A437G and K540E (IRN-GE) were detected in 0.8% (1/128) and 4.4% (1/23) of samples collected at ANC and at delivery respectively. No mutations were identified at Pfdhfr codons 16 or 164 or Pfdhps 581. There is a high prevalence of Pfdhfr triple mutant P. falciparum infections among pregnant women in the study area. However, prevalence of the combined Pfdhfr/Pfdhps quadruple and quintuple mutants IRN-GK and IRN-GE respectively prior to commencement of IPTp-SP were low, and no Pfdhps A581G mutant was detected, indicating that SP is still likely to be efficacious for IPTp-SP in the forest-savannah area in the middle belt of Ghana.
This study estimated the prevalence of curable sexually transmitted and reproductive tract infections (STIs/RTIs) among pregnant women attending antenatal care (ANC) in rural Zambia, evaluated the ...effectiveness of syndromic management of STIs/RTIs versus reference-standard laboratory diagnoses, and identified determinants of curable STIs/RTIs during pregnancy.
A total of 1086 pregnant women were enrolled at ANC booking, socio-demographic information and biological samples were collected, and the provision of syndromic management based care was documented. The Piot-Fransen model was used to evaluate the effectiveness of syndromic management versus etiological testing, and univariate and multivariate logistic regression analyses were used to identify determinants of STIs/RTIs.
Participants had a mean age of 25.6 years and a mean gestational age of 22.0 weeks. Of 1084 women, 700 had at least one STI/RTI (64.6%; 95% confidence interval CI, 61.7, 67.4). Only 10.2% of infected women received any treatment for a curable STI/RTI (excluding syphilis). Treatment was given to 0 of 56 women with chlamydia (prevalence 5.2%; 95% CI, 4.0, 6.6), 14.7% of participants with gonorrhoea (prevalence 3.1%; 95% CI, 2.2, 4.4), 7.8% of trichomoniasis positives (prevalence 24.8%; 95% CI, 22.3, 27.5) and 7.5% of women with bacterial vaginosis (prevalence 48.7%; 95% CI, 45.2, 51.2). An estimated 7.1% (95% CI, 5.6, 8.7) of participants had syphilis and received treatment. Women < 20 years old were more likely (adjusted odds ratio aOR = 5.01; 95% CI: 1.23, 19.44) to have gonorrhoea compared to women ≥30. The odds of trichomoniasis infection were highest among primigravidae (aOR = 2.40; 95% CI: 1.69, 3.40), decreasing with each subsequent pregnancy. Women 20 to 29 years old were more likely to be diagnosed with bacterial vaginosis compared to women ≥30 (aOR = 1.58; 95% CI: 1.19, 2.10). Women aged 20 to 29 and ≥ 30 years had higher odds of infection with syphilis, aOR = 3.96; 95% CI: 1.40, 11.20 and aOR = 3.29; 95% CI: 1.11, 9.74 respectively, compared to women under 20.
Curable STIs/RTIs were common and the majority of cases were undetected and untreated. Alternative approaches are urgently needed in the ANC setting in rural Zambia.
The World Health Organization (WHO) aims to reduce tuberculosis (TB) deaths by 95% by 2035; tracking progress requires accurate measurement of TB mortality. International Classification of Diseases ...(ICD) codes do not differentiate between HIV-associated TB and HIV more generally. Verbal autopsy (VA) is used to estimate cause of death (CoD) patterns but has mostly been validated against a suboptimal gold standard for HIV and TB. This study, conducted among HIV-positive adults, aimed to estimate the accuracy of VA in ascertaining TB and HIV CoD when compared to a reference standard derived from a variety of clinical sources including, in some, minimally-invasive autopsy (MIA).
Decedents were enrolled into a trial of empirical TB treatment or a cohort exploring diagnostic algorithms for TB in South Africa. The WHO 2012 instrument was used; VA CoD were assigned using physician-certified VA (PCVA), InterVA-4, and SmartVA-Analyze. Reference CoD were assigned using MIA, research, and health facility data, as available. 259 VAs were completed: 147 (57%) decedents were female; median age was 39 (interquartile range IQR 33-47) years and CD4 count 51 (IQR 22-102) cells/μL. Compared to reference CoD that included MIA (n = 34), VA underestimated mortality due to HIV/AIDS (94% reference, 74% PCVA, 47% InterVA-4, and 41% SmartVA-Analyze; chance-corrected concordance CCC 0.71, 0.42, and 0.31, respectively) and HIV-associated TB (41% reference, 32% PCVA; CCC 0.23). For individual decedents, all VA methods agreed poorly with reference CoD that did not include MIA (n = 259; overall CCC 0.14, 0.06, and 0.15 for PCVA, InterVA-4, and SmartVA-Analyze); agreement was better at population level (cause-specific mortality fraction accuracy 0.78, 0.61, and 0.57, for the three methods, respectively).
Current VA methods underestimate mortality due to HIV-associated TB. ICD and VA methods need modifications that allow for more specific evaluation of HIV-related deaths and direct estimation of mortality due to HIV-associated TB.
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