Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950-2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

BACKGROUND

Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020-21 COVID-19 pandemic period.

METHODS

22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution.

FINDINGS

Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5-65·1] decline), and increased during the COVID-19 pandemic period (2020-21; 5·1% [0·9-9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98-5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50-6·01) in 2019. An estimated 131 million (126-137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7-17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8-24·8), from 49·0 years (46·7-51·3) to 71·7 years (70·9-72·5). Global life expectancy at birth declined by 1·6 years (1·0-2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67-8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4-52·7]) and south Asia (26·3% [9·0-44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations.

INTERPRETATION

Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic.

FUNDING

Bill & Melinda Gates Foundation.

The burden of bacterial antimicrobial resistance in the WHO African region in 2019: a cross-country systematic analysis

BACKGROUND

A critical and persistent challenge to global health and modern health care is the threat of antimicrobial resistance (AMR). Previous studies have reported a disproportionate burden of AMR in low-income and middle-income countries, but there remains an urgent need for more in-depth analyses across Africa. This study presents one of the most comprehensive sets of regional and country-level estimates of bacterial AMR burden in the WHO African region to date.

METHODS

We estimated deaths and disability-adjusted life-years (DALYs) attributable to and associated with AMR for 23 bacterial pathogens and 88 pathogen-drug combinations for countries in the WHO African region in 2019. Our methodological approach consisted of five broad components: the number of deaths in which infection had a role, the proportion of infectious deaths attributable to a given infectious syndrome, the proportion of infectious syndrome deaths attributable to a given pathogen, the percentage of a given pathogen resistant to an antimicrobial drug of interest, and the excess risk of mortality (or duration of an infection) associated with this resistance. These components were then used to estimate the disease burden by using two counterfactual scenarios: deaths attributable to AMR (considering an alternative scenario where infections with resistant pathogens are replaced with susceptible ones) and deaths associated with AMR (considering an alternative scenario where drug-resistant infections would not occur at all). We obtained data from research hospitals, surveillance networks, and infection databases maintained by private laboratories and medical technology companies. We generated 95% uncertainty intervals (UIs) for final estimates as the 25th and 975th ordered values across 1000 posterior draws, and models were cross-validated for out-of-sample predictive validity.

FINDINGS

In the WHO African region in 2019, there were an estimated 1·05 million deaths (95% UI 829 000-1 316 000) associated with bacterial AMR and 250 000 deaths (192 000-325 000) attributable to bacterial AMR. The largest fatal AMR burden was attributed to lower respiratory and thorax infections (119 000 deaths [92 000-151 000], or 48% of all estimated bacterial pathogen AMR deaths), bloodstream infections (56 000 deaths [37 000-82 000], or 22%), intra-abdominal infections (26 000 deaths [17 000-39 000], or 10%), and tuberculosis (18 000 deaths [3850-39 000], or 7%). Seven leading pathogens were collectively responsible for 821 000 deaths (636 000-1 051 000) associated with resistance in this region, with four pathogens exceeding 100 000 deaths each: Streptococcus pneumoniae, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. Third-generation cephalosporin-resistant K pneumoniae and meticillin-resistant S aureus were shown to be the leading pathogen-drug combinations in 25 and 16 countries, respectively (53% and 34% of the whole region, comprising 47 countries) for deaths attributable to AMR.

INTERPRETATION

This study reveals a high level of AMR burden for several bacterial pathogens and pathogen-drug combinations in the WHO African region. The high mortality rates associated with these pathogens demonstrate an urgent need to address the burden of AMR in Africa. These estimates also show that quality and access to health care and safe water and sanitation are correlated with AMR mortality, with a higher fatal burden found in lower resource settings. Our cross-country analyses within this region can help local governments to leverage domestic and global funding to create stewardship policies that target the leading pathogen-drug combinations.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care using UK aid funding managed by the Fleming Fund.

Spatial diarrheal disease risks and antibiogram diversity of diarrheagenic Escherichia coli in selected access points of the Buffalo River, South Africa

Freshwater sources, often used for domestic and agricultural purposes in low- and middle-income countries are repositories of clinically significant bacterial pathogens. These pathogens are usually diversified in their antibiogram profiles posing public health threats. This study evaluated the spatial diarrhoeal disease risk and antibiogram diversity of diarrheagenic Escherichia coli (DEC) in four access points of the Buffalo River, Eastern Cape Province, South Africa using standard epidemiological, culture, and molecular methods. The diarrhoeal disease risk was characterised using the Monte Carlo simulation, while the antibiogram diversity was assessed using the species observed Whittaker's single alpha-diversity modelling. E. coli mean count was highest in King William's Town dam [16.0 × 102 CFU/100ml (SD: 100.0, 95% CI: 13.5 × 102 to 18.5 × 102)]. Enterohemorrhagic E. coli (stx1/stx2) was the most prevalent DEC pathotype across the study sites. A high diarrhoeal disease risk of 25.0 ×10-2 exceeding the World Health Organization's standard was recorded across the study sites. The average single and multiple antimicrobial resistance indices of the DEC to test antimicrobials were highest in the Eluxolzweni dam [0.52 (SD: 0.25, 95% CI: 0.37 to 0.67)] and King William's Town dam [0.42 (SD: 0.25, 95% CI: 0.27 to 0.57)] respectively. The prevalent antibiotic resistance genes detected were tetA, blaFOX and blaMOX plasmid-mediated AmpC, blaTEM and blaSHV extended-spectrum β-lactamases, which co-occurred across the study sites on network analysis. The phenotypic and genotypic resistance characteristics of the DEC in Maden dam (r = 0.93, p<0.00), Rooikrantz dam (r = 0.91, p<0.00), King William's Town dam (r = 0.83, p = 0.0), and Eluxolzweni dam (r = 0.91, p<0.00) were strongly correlated. At least, three phylogenetic clades of the DEC with initial steep descent alpha-diversity curves for most of the test antimicrobials were observed across the study sites, indicating high diversity. The occurrence of diversified multi drug resistant DEC with diarrhoeal disease risks in the Buffalo River substantiates the role surface water bodies play in the dissemination of drug-resistant bacterial pathogens with public health implications.

The use of artificial intelligence for delivery of essential health services across WHO regions: a scoping review

Background

Artificial intelligence (AI) is a broad outlet of computer science aimed at constructing machines capable of simulating and performing tasks usually done by human beings. The aim of this scoping review is to map existing evidence on the use of AI in the delivery of medical care.

Methods

We searched PubMed and Scopus in March 2022, screened identified records for eligibility, assessed full texts of potentially eligible publications, and extracted data from included studies in duplicate, resolving differences through discussion, arbitration, and consensus. We then conducted a narrative synthesis of extracted data.

Results

Several AI methods have been used to detect, diagnose, classify, manage, treat, and monitor the prognosis of various health issues. These AI models have been used in various health conditions, including communicable diseases, non-communicable diseases, and mental health.

Conclusions

Presently available evidence shows that AI models, predominantly deep learning, and machine learning, can significantly advance medical care delivery regarding the detection, diagnosis, management, and monitoring the prognosis of different illnesses.

Improving the availability of vaccines in primary healthcare facilities in South Africa: is the time right for a system redesign process?

An uninterrupted supply of vaccines at different supply chain levels is a basic component of a functional immunization programme and care service. There can be no progress toward achieving universal health coverage and sustainable development without continuous availability of essential medicines and vaccines in healthcare facilities. Shortages of vaccines, particularly at health facility level is an issue of grave concern that requires urgent attention in South Africa. The causes of vaccine stock-outs are multifactorial and may be linked to a broader systems issue. These factors include challenges at higher levels such as delays in the delivery of stock from the pharmaceutical depot; health facility level factors, which include a lack of commitment from healthcare workers and managers; human resource factors, such as, staff shortages, and lack of skilled personnel. Therefore, there is a compelling need to address the factors associated with shortages of vaccines in health facilities. This paper highlights the challenges of vaccine availability in South Africa, the associated factors, the available interventions, and recommended interventions for the expanded programme on immunization in South Africa. We propose a system redesign approach as a potentially useful intervention.

The impact of faith-based organizations on maternal and child health care outcomes in Africa: taking stock of research evidence

This evidence synthesis aimed at assessing the effectiveness of Faith-Based Organisations (FBOs) on Maternal and Child Health (MCH) outcomes; and explore the perceptions and experiences of the users and providers of MCH services delivered by FBOs in Africa. This review considered studies from African countries only. Both reviews and primary studies focusing on MCH services provided by FBOs were considered. Quantitative, qualitative, and mixed methods reviews were included with no restriction on the date and language. Primary outcomes included maternal mortality ratio, neonatal mortality, infant mortality, child mortality, quality of care, views, experiences, and perceptions of users of FBOs. We searched up to November 2020 in the Joanna Briggs Institute (JBI) Database of Systematic Reviews and Implementation Reports, the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, PROSPERO register, PDQ-evidence, Health Systems Evidence, CINAHL, EMBASE, and PubMed. We searched references cited by similar studies that may be potentially eligible for inclusion. We then updated the search for primary studies from December 2009 - October 2020. One systematic review and six primary studies met the eligibility criteria for inclusion. Methodological quality varied. These observational and qualitative studies found that FBOs offered the following MCH services - training of healthcare workers, obstetric services, health promotion, sexual education, immunization services, and intermittent preventive therapy for malaria. Maternal and Child Health (MCH) services provided by FBO suggest a reduction in maternal morbidity and mortality. Increased uptake of maternal healthcare services, and increased satisfaction were reported by users of care. However, costs of providing these services varied across the studies and users. This review shows that FBOs play an important role in improving access and delivery of MCH services and have the potential of strengthening the health system at large. Rigorous research is needed to ascertain the effectiveness of FBO-based interventions in strengthening the health systems in Africa.

Strengthening the Health System as a Strategy to Achieving a Universal Health Coverage in Underprivileged Communities in Africa: A Scoping Review

Universal health coverage (UHC) is defined as people having access to quality healthcare services (e.g., treatment, rehabilitation, and palliative care) they need, irrespective of their financial status. Access to quality healthcare services continues to be a challenge for many people in low- and middle-income countries (LMICs). The aim of this study was to conduct a scoping review to map out the health system strengthening strategies that can be used to attain universal health coverage in Africa. We conducted a scoping review and qualitatively synthesized existing evidence from studies carried out in Africa. We included studies that reported interventions to strengthen the health system, e.g., financial support, increasing work force, improving leadership capacity in health facilities, and developing and upgrading infrastructure of primary healthcare facilities. Outcome measures included health facility infrastructures, access to medicines, and sources of financial support. A total of 34 studies conducted met our inclusion criteria. Health financing and developing health infrastructure were the most reported interventions toward achieving UHC. Our results suggest that strengthening the health system, namely, through health financing, developing, and improving the health infrastructure, can play an important role in reaching UHC in the African context.

Patient safety education for undergraduate nursing students: a scoping review protocol

OBJECTIVE

The objective of the review is to examine the literature on patient safety and the teaching and learning strategies required to help students learn about patient safety in undergraduate nursing curricula in prelicensure nursing education programs.

INTRODUCTION

Patient safety is a global concern, and health care professionals, including nurses who are on the frontline of health care delivery, should be equipped with the knowledge to enhance patient safety. Undergraduate nursing curricula should include the relevant patient safety content and supply nurse educators with teaching and learning strategies to help students acquire these skills.

INCLUSION CRITERIA

Based on the Participants, Concept, and Context (PCC) framework, the eligible population will include nursing students who are enrolled in undergraduate nursing programs and nurse educators who teach in undergraduate nursing programs. The concept of interest is patient safety education, namely, the curricular content and teaching and learning strategies used to help nursing students learn the content. The context is prelicensure nursing education programs at college or university level. Eligible studies will include, but not be limited to, quantitative studies, observational, qualitative, and mixed-methods studies, systematic reviews, and opinion papers.

METHODS

Online databases will be searched across MEDLINE, CINAHL, and Web of Science. JBI methodology for scoping reviews will be used to conduct the review. Pre-determined inclusion and exclusion criteria will be used to select relevant studies. Data will be extracted and synthesized from studies that describe patient safety content and teaching and learning strategies in prelicensure nursing education.

Preventing and managing antimicrobial resistance in the African region: A scoping review protocol

Introduction

Antimicrobial resistance (AMR) constitutes a significant threat to global health and food security, typically associated with high morbidity and mortality rate. The high burden of infectious diseases coupled with the weak health systems in most countries of Africa magnifies the risk of increasing AMR and its consequences thereof. This scoping review will be aimed at mapping the evidence on interventions used to prevent and manage antimicrobial resistance in Africa, guided by the “One Health” concept.

Methods

We will consider interventions targeting multiple sectors such as health care systems, the agricultural and veterinary sectors. The outcomes to be considered include reduction of AMR decreased morbidity and mortality due to infectious diseases, increased awareness for rational use of antimicrobials and reduced antibiotic consumption. We will include all types of studies regardless of study designs conducted within the context of the WHO African region. Studies will be excluded if they are not conducted in Africa and if they are literature reviews, only describing the concept of AMR without mentioning interventions.

We will include studies identified through a comprehensive search of peer-reviewed and grey literature databases. In addition, we will search the reference lists of included studies and relevant reviews. Finally, we plan to do a citation search for included studies. Findings of this review will be narratively synthesized.

Missed opportunities for vaccination in Africa

The purpose of this review is to assess the extent of missed opportunities for vaccination (MOV) in Africa, determine the associated factors, and provide recommendations that countries could adopt in reducing MOV. Two databases were searched for multinational studies and systematic reviews reporting MOV and involving African countries. A total of 288 records were identified and 12 studies included for synthesis. The prevalence ranged from 47.0% to 62.1%, with a weighted mean of 27.3%. This review highlighted caregiver utilization, health service delivery, and healthcare worker' factors associated with MOV. Understanding the extent of MOV in Africa presents an opportunity for multiple approaches to resolve the differential factors that contribute to MOV, and to bridge the gap in vaccination coverage in the continent.

Reflection: burden of cervical cancer in Sub-Saharan Africa and progress with HPV vaccination

In Sub-Saharan (SSA) cervical cancer is the leading cause of cancer deaths amongst women. The region carries the greatest burden, with 24.55% of the global mortality from cervical cancer. Reports indicate an increasing challenge of cervical cancer in SSA. HPV vaccination with its well-established effectiveness provides hope for cancer control in SSA. Following an initial delay in HPV vaccine uptake in SSA, 18 countries mostly in Eastern and Southern Africa, had a national programme by 2020. Vaccination coverage data show that high populated countries have lower coverage figures. Furthermore, high coverage of demonstration projects may not be achieved in the national rollout. In conclusion, whilst there is significant progress with the rollout of HPV vaccination programme in SSA, some countries in West Africa should be prioritised. Experiences of early adopters should be reviewed to guide other countries to achieve and sustain high coverage.