Zika virus is an arthropod-borne virus that is a member of the family Flaviviridae transmitted mainly by mosquitoes of the genus Aedes. Although usually asymptomatic, infection can result in a mild and self-limiting illness characterised by fever, rash, arthralgia, and conjunctivitis. An increase in the number of children born with microcephaly was noted in 2015 in regions of Brazil with high transmission of Zika virus. More recently, evidence has been accumulating supporting a link between Zika virus and microcephaly. Here, we describe findings from three fatal cases and two spontaneous abortions associated with Zika virus infection.

Published work suggests a survival benefit for patients with trauma who undergo total-body CT scanning during the initial trauma assessment; however, level 1 evidence is absent. We aimed to assess the effect of total-body CT scanning compared with the standard work-up on in-hospital mortality in patients with trauma.

Measurements of health indicators are rarely available for every population and period of interest, and available data may not be comparable. The Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER) define best reporting practices for studies that calculate health estimates for multiple populations (in time or space) using multiple information sources. Health estimates that fall within the scope of GATHER include all quantitative population-level estimates (including global, regional, national, or subnational estimates) of health indicators, including indicators of health status, incidence and prevalence of diseases, injuries, and disability and functioning; and indicators of health determinants, including health behaviours and health exposures. GATHER comprises a checklist of 18 items that are essential for best reporting practice. A more detailed explanation and elaboration document, describing the interpretation and rationale of each reporting item along with examples of good reporting, is available on the GATHER website.

Private health care in low-income and middle-income countries is very extensive and very heterogeneous, ranging from itinerant medicine sellers, through millions of independent practitioners-both unlicensed and licensed-to corporate hospital chains and large private insurers. Policies for universal health coverage (UHC) must address this complex private sector. However, no agreed measures exist to assess the scale and scope of the private health sector in these countries, and policy makers tasked with managing and regulating mixed health systems struggle to identify the key features of their private sectors. In this report, we propose a set of metrics, drawn from existing data that can form a starting point for policy makers to identify the structure and dynamics of private provision in their particular mixed health systems; that is, to identify the consequences of specific structures, the drivers of change, and levers available to improve efficiency and outcomes. The central message is that private sectors cannot be understood except within their context of mixed health systems since private and public sectors interact. We develop an illustrative and partial country typology, using the metrics and other country information, to illustrate how the scale and operation of the public sector can shape the private sector's structure and behaviour, and vice versa.

The private sector has a large and growing role in health systems in low-income and middle-income countries. The goal of universal health coverage provides a renewed focus on taking a system perspective in designing policies to manage the private sector. This perspective requires choosing policies that will contribute to the performance of the system as a whole, rather than of any sector individually. Here we draw and extrapolate main messages from the papers in this Series and additional sources to inform policy and research agendas in the context of global and country level efforts to secure universal health coverage in low-income and middle-income countries. Recognising that private providers are highly heterogeneous in terms of their size, objectives, and quality, we explore the types of policy that might respond appropriately to the challenges and opportunities created by four stylised private provider types: the low-quality, underqualified sector that serves poor people in many countries; not-for-profit providers that operate on a range of scales; formally registered small-to-medium private practices; and the corporate commercial hospital sector, which is growing rapidly and about which little is known.

Although the private sector is an important health-care provider in many low-income and middle-income countries, its role in progress towards universal health coverage varies. Studies of the performance of the private sector have focused on three main dimensions: quality, equity of access, and efficiency. The characteristics of patients, the structures of both the public and private sectors, and the regulation of the sector influence the types of health services delivered, and outcomes. Combined with characteristics of private providers-including their size, objectives, and technical competence-the interaction of these factors affects how the sector performs in different contexts. Changing the performance of the private sector will require interventions that target the sector as a whole, rather than individual providers alone. In particular, the performance of the private sector seems to be intrinsically linked to the structure and performance of the public sector, which suggests that deriving population benefit from the private health-care sector requires a regulatory response focused on the health-care sector as a whole.

The private for-profit sector's prominence in health-care delivery, and concern about its failures to deliver social benefit, has driven a search for interventions to improve the sector's functioning. We review evidence for the effectiveness and limitations of such private sector interventions in low-income and middle-income countries. Few robust assessments are available, but some conclusions are possible. Prohibiting the private sector is very unlikely to succeed, and regulatory approaches face persistent challenges in many low-income and middle-income countries. Attention is therefore turning to interventions that encourage private providers to improve quality and coverage (while advancing their financial interests) such as social marketing, social franchising, vouchers, and contracting. However, evidence about the effect on clinical quality, coverage, equity, and cost-effectiveness is inadequate. Other challenges concern scalability and scope, indicating the limitations of such interventions as a basis for universal health coverage, though interventions can address focused problems on a restricted scale.