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Historical records reveal the temporal patterns of a sequence of plague epidemics in London, United Kingdom, from the 14th to 17th centuries. Analysis of these records shows that later epidemics spread significantly faster (“accelerated”). Between the Black Death of 1348 and the later epidemics that culminated with the Great Plague of 1665, we estimate that the epidemic growth rate increased fourfold. Currently available data do not provide enough information to infer the mode of plague transmission in any given epidemic; nevertheless, order-of-magnitude estimates of epidemic parameters suggest that the observed slow growth rates in the 14th century are inconsistent with direct (pneumonic) transmission. We discuss the potential roles of demographic and ecological factors, such as climate change or human or rat population density, in driving the observed acceleration.

Plague epidemics have afflicted human populations since at least the sixth century (1, 2). These events have had dramatic and long-lasting effects on human demography and behavior, especially those outbreaks associated with the second pandemic (14th to 19th centuries) in Europe and Asia (1, 35), and have inspired many theoretical studies of the ecology and evolution of infectious disease (613). We are now in the third pandemic (Modern Plague), with outbreaks continuing to occur in some parts of the world (1418). Plague also remains a source of concern due to the bioterror potential of the causative agent, Yersinia pestis (19, 20).Recent advances in paleogenomics have definitively established that historical plague pandemics were caused by Y. pestis (21, 22), as proposed in the 19th century after Yersin discovered the bacterium’s link to bubonic plague (23). Researchers have reconstructed the evolutionary history of plague and other pathogens by sequencing and reconstructing nearly complete pathogen genomes from persistent DNA fragments (21, 24, 25). The strain isolated from victims of the Black Death (London 1348) is remarkably similar to extant human strains (Modern Plague): the core genomes*of these strains are 99.99% similar (21), which makes it challenging to identify important evolutionary or ecological patterns from genomic investigations alone. Here we complement genetic studies by exploring more traditional (historical, demographic, and epidemiological) sources of information from a 300-y span of plague outbreaks in the same location (London), revealing a striking change in plague transmission dynamics over the course of the Renaissance period, namely, a fourfold increase in the initial growth rate of outbreaks.We quantify this change without making any assumptions about the underlying transmission processes, exploiting methodology that we have developed previously for this purpose (26). We then consider how this inference can contribute to the debate concerning whether plague transmission was primarily indirect (via rat fleas) or direct (pneumonic human-to- human). We argue that strictly pneumonic transmission in the 14th century is implausible but that beyond this the best that can be done at present is to highlight the biological complexities and uncertainties that limit the potential for further inferences.  相似文献   
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Background

There is increasing emphasis on involving intended beneficiaries and other stakeholders in the development of public health interventions to maximise acceptability and remove barriers to adoption, implementation, and maintenance before costly implementation. Yet the processes whereby key actors are engaged in intervention development are rarely reported, and frameworks for carrying out such work remain limited. We outline our approach to involving stakeholders in the optimisation of two school-based relationships and sex education programmes (Project Respect and Positive Choices) and reflect on the challenges of co-producing with teachers, students, and other partners.

Methods

Systematic optimisation of both interventions involved a review of existing literature on effective approaches; consultation with staff and students on intervention content and delivery; drafting of intervention materials; further consultation with schools; and then intervention refinement in preparation for a pilot. Seven focus groups took place in southeast and southwest England involving 75 students aged 13–15 years and 22 school staff. A group of young people trained to advise on public health research were consulted on two occasions and a wide range of sexual health and sex education practitioners and policy makers shared their views at a stakeholder event.

Findings

Consultation provided useful insights to inform intervention adaption in relation to who should deliver the programmes in schools; whether lessons should be taught in single sex classes; the format that guidance and lesson plans should take; the relevance and acceptability to students and teachers; and the need for the flexibility for materials to adapt to different school contexts. Genuine consultation and incorporation of school stakeholder views was challenging where stakeholder availability was limited and intervention development and implementation timelines were tight. Challenges also arose in relation to the weight to give divergent opinions among stakeholders and between stakeholders and researchers.

Interpretation

Carrying out structured stakeholder engagement activities can yield valuable insights that can improve the applicability of interventions to local contexts before they are formally trialled. To genuinely engage stakeholders in intervention development requires sufficient time to both consult and adapt. In such consultations, it is important to attend not just to the voices of those who are the loudest and most powerful.

Funding

National Institute for Health Research (NIHR).  相似文献   
35.

Background

Routine sources of information on the maternal and child health workforce in China are without clear definition and categorisation. The aim of the study was to systematically review all the evidence on China's maternal and child health workforce profile (ie, level of education, training, qualification, and professional title), and determine the density of the maternal and child health workforce.

Methods

We did a systematic review by searching six English (Embase, MEDLINE, CENTRAL, EconLit, Global Health, and Web of Science) and two Chinese (Wanfang and China National Knowledge Infrastructure) databases, from 1949 onwards, using a combination of the search terms “human resources for health”, “maternal and child health services”, and “China” with both thesaurus and free text words. We included studies either describing the profile of the maternal and child health workforce or providing data allowing us to calculate the density of the maternal and child health workforce.

Findings

We included 58 studies: 43 reporting profiles of the maternal and child health workforce, and 19 reporting density of the maternal and child health workforce, four of which covered both. 51 (88%) of the 58 studies were done after 1990. The maternal and child health workforce in China covers an array of professions, including obstetricians, gynaecologists, neonatologists, paediatricians, nurses, midwives, general physicians, specialised public health workers, vaccinators, barefoot doctors (ie, farmers who go through short-term medical training), and traditional birth attendants. Definitions of who qualifies as a maternal and child health provider are not clear (eg, the term midwife was used in six studies, and covered a range of training, including clinical medicine, maternal and child health care, nursing, and midwifery). Two studies reported that 7% (24 of 321) and 48% (650 of 1364), respectively, of the maternal and child health workforce at county-level facilities or below held no certificate for maternal and child health care. Only one study reported the density of the maternal and child health workforce at a national level, which was 0·6 health professionals per 1000 population in 2011. The density of the maternal health workforce was between 1·6 and 6·5 times higher than the child health workforce in the same population. The ratio of obstetric nurses to obstetricians ranged from 1·3:1 to 2·0:1, which was higher than the overall nurse-to-doctor ratio at a national level of 1·1:1 in 2017. The ratio of paediatric nurses to paediatricians ranged from 1·1:1 to 1·7:1, which was higher than the national ratio of 1·1:1.

Interpretation

The density of the maternal and child health workforce in China is lower than the minimum desired level of 2·3 health professionals (physicians, nurses, and midwives) per 1000 population, as recommended in the World Health Report 2006. The maternal and child health workforce in China is characterised by varied personnel with diverse training backgrounds, a larger maternal health workforce than child health workforce, and more nurses than doctors. A strength of the study is the conceptual understanding of the maternal and child health workforce over the entire period of contemporary China. A limitation of the study is that various data sources prevented us from synthesising the available evidence together.

Funding

China Medical Board.  相似文献   
36.
In a consecutive study of 49 patients with obstructive jaundice who underwent preoperative percutaneous transhepatic drainage, the incidence of bacteria in bile at the time of insertion of the drainage catheter was 29 percent. Patients drained with a conventional open drainage system showed an increase to 100 percent positive cultures after 20 days drainage. In this group, there was also a high incidence of episodes of bacteremia preoperatively and postoperatively and a high incidence of positive wound cultures. An antiseptic barrier incorporated into the drainage system reduced the incidence of positive bile cultures during the drainage period although this did not afford a significant reduction in bacteremic episodes and positive wound cultures. Using a new closed drainage system, the acquisition of environmental organisms to the bile was eliminated which allowed a significant reduction in septic complications both preoperatively and postoperatively. This new closed drainage system increased the value of preoperative decompression of the obstructed biliary tree by preventing exogenous bacterial contamination and reducing associated septic episodes.  相似文献   
37.
Survival with a good quality of life after cardiac arrest continues to be abysmal. Coordinated resuscitative care does not end with the effective return of spontaneous circulation (ROSC)—in fact, quite the contrary is true. Along with identifying and appropriately treating the precipitating cause, various components of the post–cardiac arrest syndrome also require diligent observation and management, including post–cardiac arrest neurologic injury and myocardial dysfunction, systemic ischemia-reperfusion phenomenon with potential consequent multiorgan failure, and the various sequelae of critical illness. There is growing evidence that an early invasive approach to coronary reperfusion with percutaneous coronary intervention, together with active targeted temperature management and optimization of hemodynamic, ventilator, and metabolic parameters, may improve survival and neurologic outcomes in cardiac arrest survivors. Neuroprognostication is complex, as are survivorship issues and long-term rehabilitation. Our paramedics, emergency physicians, and resuscitation specialists are all to be congratulated for ever-increasing success with ROSC… but now the real work begins.  相似文献   
38.
Heart failure (HF) is a significant public health concern. Specialized HF clinics provide the optimal environment to address the complex needs of these patients and improve outcomes. The current and growing population of patients with HF outstrips the ability of these clinics to deliver care. Integrated care is defined as health services that are managed and delivered so that people receive a seamless continuum of health promotion, disease prevention, diagnosis, treatment, disease management, rehabilitation, and palliative care services. This approach requires coordination across different levels and sites of care within and beyond the health sector, according to changing patient needs throughout their lives. The spoke-hub-and-node (SHN) model represents an organization of care that works collaboratively with the primary care sector and is highly integrated with community-based multidisciplinary teams of health care professionals and specialty care. The purpose of this article is to analyze the requirements for successful implementation of SHN models. We consider the respective roles of HF clinics, HF nurse specialists, pharmacists, palliative care teams, telemonitoring, and solo practitioners. We also discuss levels of care delivery and the importance of patient stratification and patient flow. The SHN approach has the potential to build on and improve the chronic care model (CCM) to deliver centralized services to preserve high-quality patient-centred care at affordable costs.  相似文献   
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