Findings From Severe Maternal Morbidity Surveillance and Review in Maryland.

Importance: In the US, more than 50 000 women experience severe maternal morbidity (SMM) each year, and the SMM rate more than doubled during the past 25 years. In response, professional organizations called for birthing facilities to routinely identify and review SMM events and identify prevention opportunities. Objective: To examine SMM levels, primary causes, and factors associated with the preventability of SMM using Maryland's SMM surveillance and review program. Design, Setting, and Participants: This cross-sectional study included pregnant and postpartum patients at 42 days or less after delivery who were hospitalized at 1 of 6 birthing hospitals in Maryland between August 1, 2020, and November 30, 2021. Hospital-based SMM surveillance was conducted through a detailed review of medical records. Exposures: Hospitalization during pregnancy or within 42 days post partum. Main Outcomes and Measures: The main outcomes were admission to an intensive care unit, having at least 4 U of red blood cells transfused, and/or having COVID-19 infection requiring inpatient hospital care. Results: A total of 192 SMM events were identified and reviewed. Patients with SMM had a mean [SD] age of 31 [6.49] years; 9 [4.7%] were Asian, 27 [14.1%] were Hispanic, 83 [43.2%] were non-Hispanic Black, and 68 [35.4%] were non-Hispanic White. Obstetric hemorrhage was the leading primary cause of SMM (83 [43.2%]), followed by COVID-19 infection (57 [29.7%]) and hypertensive disorders of pregnancy (17 [8.9%]). The SMM rate was highest among Hispanic patients (154.9 per 10 000 deliveries), primarily driven by COVID-19 infection. The rate of SMM among non-Hispanic Black patients was nearly 50% higher than for non-Hispanic White patients (119.9 vs 65.7 per 10 000 deliveries). The SMM outcome assessed could have been prevented in 61 events (31.8%). Clinician-level factors and interventions in the antepartum period were most frequently cited as potentially altering the SMM outcome. Practices that were performed well most often pertained to hospitals' readiness and adequate response to managing pregnancy complications. Recommendations for care improvement focused mainly on timely recognition and rapid response to such. Conclusions and Relevance: The findings of this cross-sectional study, which used hospital-based SMM surveillance and review beyond the mere exploration of administrative data, offers opportunities for identifying valuable quality improvement strategies to reduce SMM. Immediate strategies to reduce SMM in Maryland should target its most common causes and address factors associated with preventability identified at individual hospitals.

Differential Effects of Temperature and Mosquito Genetics Determine Transmissibility of Arboviruses by Aedes aegypti in Argentina.

Aedes aegypti (L.) (Diptera: Culicidae) have a global distribution and are the primary vector of a number of mosquito-borne viruses responsible for epidemics throughout the Americas. As in much of South America, the threat from pathogens including dengue virus (DENV; Flaviviridae, Flavivirus) and chikungunya virus (CHIKV; Togaviridae, Alphavirus) has increased in Argentina in recent years. The complexity of transmission cycles makes predicting the occurrence and intensity of arbovirus outbreaks difficult. To gain a better understanding of the risk of DENV and CHIKV in Argentina and the factors influencing this risk, we evaluated the role of population and temperature in the vector competence and vectorial capacity (VC) of Ae. aegypti from geographically and ecologically distinct locations. Our results demonstrate that intrinsic and extrinsic factors including mosquito population, viral species, and temperature significantly influence both vector competence and overall VC of Ae. aegypti in Argentina, yet also that the magnitude of these influences is highly variable. Specifically, results suggest that CHIKV competence is more dependent on mosquito genetics than is DENV competence, whereas temperature has a greater effect on DENV transmission. In addition, although there is an overall positive correlation between temperature and competence for both viruses, there are exceptions to this for individual virus-population combinations. Together, these data establish large variability in VC for these pathogens among distinct Ae. aegypti populations in Argentina and demonstrate that accurate assessment of arbovirus risk will require nuanced models that fully consider the complexity of interactions between virus, temperature, mosquito genetics, and hosts.

The effect of hybridization of Culex pipiens complex mosquitoes on transmission of West Nile virus.

BACKGROUND: Culex pipiens L. complex mosquitoes have a global distribution and are primary vectors of pathogens of public health significance. In the U.S., Cx. pipiens bioformes, Cx. pipiens form pipiens and Cx. pipiens form molestus, as well as Cx. quinquefasciatus, are primary vectors of West Nile virus (WNV; Flaviviridae, Flavivirus). These mosquitoes reside in distinct but overlapping ecological niches and readily hybridize in areas where they coexist. Although species and population-specific differences in vector competence of Culex mosquitoes for WNV have been identified, the extent to which hybridization within this complex alters WNV transmission potential has not been well characterized. FINDINGS: WNV vector competence of laboratory colonies of Cx. p. f. pipiens, Cx. p. f. molestus, and Cx. quinquefasciatus was assessed and compared to hybrid populations created from reciprocal mating of these lines. The results demonstrate that hybridization has a significant effect on WNV infection, dissemination, and, particularly, transmission in Culex pipiens L. complex mosquitoes. Specifically, enhanced transmission of WNV was measured in all hybrid populations relative to one or both parental stains. CONCLUSION: These findings demonstrate that environmental or anthropogenic changes resulting in fluctuations in the distribution and extent of hybrid populations of Culex mosquitoes could have a significant impact on transmission patterns of WNV in nature.

α-Synuclein induces both positive mean curvature and negative Gaussian curvature in membranes.

Using a combination of X-ray scattering, fluorescence correlation spectroscopy, coarse-grained molecular dynamics (MD) simulations and potential of mean force calculations, we have explored the membrane remodeling effects of monomeric α-synuclein (αS). Our initial findings from multiple approaches are that αS (1) causes a significant thinning of the bilayer and (2) stabilizes positive mean curvature, such that the maximum principle curvature matches that of synaptic vesicles, αS-induced tubules, and the synthetic lipid vesicles to which the protein binds most tightly. This suggests that αS binding to synaptic vesicles likely stabilizes their intrinsic curvature. We then show that αS induces local negative Gaussian curvature, an effect that occurs in regions of αS shown previously via NMR and corroborated by MD simulation to have significant conformational flexibility. The induction of negative Gaussian curvature, which has implications for all curvature-sensing and curvature-generating amphipathic α-helices, supports a hypothesis that connects helix insertion to fusion and fission of vesicles, processes that have recently been linked to αS function. Then, in an effort to explain these biophysical properties of αS, we promote an intrinsic curvature-field model that recasts long-range protein-protein interactions in terms of the interactions between the local curvature fields generated by lipid-protein complexes.