An Analysis of Pregnancy-Related Mortality in the KEMRI/CDC Health and Demographic Surveillance System in Western Kenya

Background

Pregnancy-related (PR) deaths are often a result of direct obstetric complications occurring at childbirth.

Methods and Findings

To estimate the burden of and characterize risk factors for PR mortality, we evaluated deaths that occurred between 2003 and 2008 among women of childbearing age (15 to 49 years) using Health and Demographic Surveillance System data in rural western Kenya. WHO ICD definition of PR mortality was used: “the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the cause of death”. In addition, symptoms and events at the time of death were examined using the WHO verbal autopsy methodology. Deaths were categorized as either (i) directly PR: main cause of death was ascribed as obstetric, or (ii) indirectly PR: main cause of death was non-obstetric. Of 3,223 deaths in women 15 to 49 years, 249 (7.7%) were PR. One-third (34%) of these were due to direct obstetric causes, predominantly postpartum hemorrhage, abortion complications and puerperal sepsis. Two-thirds were indirect; three-quarters were attributable to human immunodeficiency virus (HIV/AIDS), malaria and tuberculosis. Significantly more women who died in lower socio-economic groups sought care from traditional birth attendants (p = 0.034), while less impoverished women were more likely to seek hospital care (p = 0.001). The PR mortality ratio over the six years was 740 (95% CI 651–838) per 100,000 live births, with no evidence of reduction over time (χ² linear trend = 1.07; p = 0.3).

Conclusions

These data supplement current scanty information on the relationship between infectious diseases and poor maternal outcomes in Africa. They indicate low uptake of maternal health interventions in women dying during pregnancy and postpartum, suggesting improved access to and increased uptake of skilled obstetric care, as well as preventive measures against HIV/AIDS, malaria and tuberculosis among all women of childbearing age may help to reduce pregnancy-related mortality.     

Lithium Fluoride Based Electron Contacts for High Efficiency n‐Type Crystalline Silicon Solar Cells

Low‐resistance contact to lightly doped n‐type crystalline silicon (c‐Si) has long been recognized as technologically challenging due to the pervasive Fermi‐level pinning effect. This has hindered the development of certain devices such as n‐type c‐Si solar cells made with partial rear contacts (PRC) directly to the lowly doped c‐Si wafer. Here, a simple and robust process is demonstrated for achieving mΩ cm² scale contact resistivities on lightly doped n‐type c‐Si via a lithium fluoride/aluminum contact. The realization of this low‐resistance contact enables the fabrication of a first‐of‐its‐kind high‐efficiency n‐type PRC solar cell. The electron contact of this cell is made to less than 1% of the rear surface area, reducing the impact of contact recombination and optical losses, permitting a power conversion efficiency of greater than 20% in the initial proof‐of‐concept stage. The implementation of the LiF_x/Al contact mitigates the need for the costly high‐temperature phosphorus diffusion, typically implemented in such a cell design to nullify the issue of Fermi level pinning at the electron contact. The timing of this demonstration is significant, given the ongoing transition from p‐type to n‐type c‐Si solar cell architectures, together with the increased adoption of advanced PRC device structures within the c‐Si photovoltaic industry.     

Infection-Mediated Priming of Phagocytes Protects against Lethal Secondary Aspergillus fumigatus Challenge

Phagocytes restrict the germination of Aspergillus fumigatus conidia and prevent the establishment of invasive pulmonary aspergillosis in immunecompetent mice. Here we report that immunecompetent mice recovering from a primary A. fumigatus challenge are protected against a secondary lethal challenge. Using RAGγc knock-out mice we show that this protection is independent of T, B and NK cells. In protected mice, lung phagocytes are recruited more rapidly and are more efficient in conidial phagocytosis and killing. Protection was also associated with an enhanced expression of CXCR2 and Dectin-1 on bone marrow phagocytes. We also show that protective lung cytokine and chemokine responses are induced more rapidly and with enhanced dynamics in protected mice. Our findings support the hypothesis that following a first encounter with a non-lethal dose of A. fumigatus conidia, the innate immune system is primed and can mediate protection against a secondary lethal infection.     

User and Provider Acceptability of Intermittent Screening and Treatment and Intermittent Preventive Treatment with Dihydroartemisinin-Piperaquine to Prevent Malaria in Pregnancy in Western Kenya

Background

The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) alongside long-lasting insecticide-treated nets (LLIN) and case management for reducing the risks associated with malaria in pregnancy in areas of moderate-to-high transmission in sub-Saharan Africa. Due to increasing Plasmodium falciparum resistance to SP, the search for alternative drugs or strategies to control malaria in pregnancy is a priority. We assessed the acceptability among pregnant women and health providers of intermittent screening and treatment (ISTp) and IPTp with dihydroartemisinin-piperaquine (DP) as alternative strategies in the context of an un-blinded clinical trial.

Methods

Qualitative data were collected through ten focus group discussions with women participating in a randomized controlled trial to evaluate ISTp or IPTp with DP (multi-day regimen) versus IPTp with SP (single dose) in western Kenya. Individual in-depth interviews were conducted with 26 health providers working in the trial facilities and trial staff.

Results

Women appreciated the advantages of being tested with a rapid diagnostic test (RDT) at every ANC visit (although a few women disliked finger pricks) and accepted that they would not receive any antimalarial when tested RDT-negative. There were differences in women’s experiences of the efficacy of antimalarials between the trial arms, with more women in the IPTp-SP arm reporting they had experienced malaria episodes. Side effects were experienced among women taking DP and SP. Although women and trial staff reported adherence to the full DP regimen within the trial, health providers were not confident that women would adhere to multi-day regimens in non-trial settings. Health providers recognized the advantages of ISTp in reducing unnecessary exposure to drugs, but lacked confidence in the reliability of RDTs compared to microscopy.

Conclusions

Our findings indicate that, within a trial context, ISTp-DP and IPTp-DP were generally acceptable among both users and providers and were regarded as potentially valuable alternatives to IPTp-SP. Several challenges were identified the most important of which was concerns with achieving adherence to DP in non-trial settings, requiring operational feasibility studies in routine health systems. Policy adoption of ISTp with RDTs would require a major shift in thinking among health providers due to lack of confidence in RDTs.     

The contrasting effects of short‐ and long‐term habitat drainage on the population dynamics of freshwater turtles in a human‐dominated landscape

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