ETIOLOGY AND RISK FACTORS OF STOMATITIS AMONG YEMENI DENTURE WEARERS

Objectives: Denture stomatitis (DS) is a benign condition, usually asymptomatic, that can affect denture wearer’s patients. The aim of this study was to describe the etiology of DS among Yemeni denture wearers and the risk factors of DS. A cross sectional study was carried out at Prothodontics Departments at the Faculty of Dentistry- Sana'a University, Sana’a city –Yemen. Methods: The study group consisted of 288 denture wearers' patients' contracting DS. The microbiological samples were collected by wiping sterile swabs on upper and lower denture fitting surfaces. Then, they were directly cultured for Candida in Chromomeric agar media and for bacteria in standard selective media, using standard bacteriological methods.  Results: The most common microbial cause of DS was C. albicans (58.3%), followed by S. mutans (17%), while S. aureus (4.9%), lactobacillus (3.1%) and C. glabrata (4.2%) were less common. There was an association between male patients, older age group and longer period of denture wearers with high risk of contracting candidal DS and bacterial DS. Most of those patients were suffering from DS Type I and few from Type II, but no case of DS Type III was found. Ending, DS is a condition that commonly affects denture wearers, and should be treated even if asymptomatic. The condition requires a combined treatment approach from both patient and clinician, and the role of the patient must be stressed. Conclusion: Management of aetiological risk factors is key in order to prevent recurrence. Treatment modalities may include: treatment of any underlying systemic risk factors, improvement in the fit of existing dentures, replacement of existing dentures, improved denture hygiene and the use of antifungal agents. Whichever methods are employed, the main aim of treatment is to eradicate the biofilm from the patient’s dentures. Peer Review History: Received 11 January 2017; Revised 13 February; Accepted 27 February, Available online 15 March 2018 Received file:        Reviewer's Comments: Average Peer review marks at initial stage: 4.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Dr. Marwa A. A. Fayed, University of Sadat City, Egypt, [email protected] Dr. Masoumeh Divar, Shiraz University, Shiraz, Iran, [email protected] Similar Articles: RISK FACTORS OF PERIODONTAL DISEASES AMONG YEMENI YOUNG DENTAL PATIENTS SERO-PREVALENCE OF HEPATITIS C VIRUS AMONG DENTAL CLINIC WORKERS IN SANA’A CITY- YEMEN AND THE RISK FACTORS CONTRIBUTING FOR ITS INFECTIO

EPIDEMICITY OF VIBRIO CHOLERA IN SANA’A CITY, YEMEN: PREVALENCE AND POTENTIAL DETERMINANTS

Objectives: In 2017, a total of 889854 suspected cholera cases with 2578 deaths were reported from Yemen, thus WHO considered these figures to be the worst epidemic of cholera in recent history of humanity. The aims of the study were to determine the prevalence of Vibrio cholera and protozoa causes in severe diarrhea patients and the potential risk factors of the contracting Vibrio cholera. Methods: Hospital-based diarrhoeal disease surveillance has been done for 12 days in Bany-alharth district of Sana'a city, where all patients admitted with severe diarrhoea in all health centers in the area were enrolled and tested for Vibrio cholerae, and others causes. The study was conducted on 345 patients and demographic, clinical, and potential risk factors were collected, then stool specimens were collected and processed by standard methods. Results:  The prevalence of V. cholerae was 8.1%, intestinal Entamoeba histolytica was 50.7%, and Giardia lamblia was 6.7% and one case of EPEC while 42% of diarrheal cases were undiagnosed. There was slightly increasing in the rate of V. cholerae infection with increasing age (15%). Also there were significant risk factors of dispose sewages to surround environment (OR=3.4 times, PV=0.02) and reused Jerry can bottles for drinking water (OR=3.1, PV= 0.03) with V.cholerae infection Vibrio cholera infection rate and intestinal protozoa infection rates were significantly high. Conclusion:  The findings emphasize that there is cholera epidemic in Sana' city and diarrheal epidemic due to various diagnosed and non diagnosed pathogenic microorganisms which may predispose population of the study to significant health risks. Peer Review History: Received 26 November 2017;   Revised 10 December; Accepted 18 December, Available online 15 January 2018 Academic Editor: Dr. Amany Mohamed Alboghdadly, Princess Nourah bint abdulrahman university, Riyadh, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:        Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Prof. Dr. Kaijian Hou, Endocrine Department, Longhu, First Affiliated Hospital of Shantou University, Shantou city, PR China, [email protected] Dina Abd Elfattah Eldakhs, Pharos university (PUA), Egypt,  [email protected]    Similar Articles: ANTI-DIARRHEAL ACTIVITY OF ETHANOL AND CHLOROFORM SEED EXTRACT OF COLA NITIDA IN EXPERIMENTALLY INDUCED DIARRHE

RADIOGRAPHIC ASSESSMENT OF THE COURSE AND VISIBILITY OF THE MANDIBULAR CANAL BY PANORAMIC RADIOGRAPHY

Background and Objectives:  The mandibular canal is a canal inside the mandible that contains the inferior alveolar artery, the inferior alveolar nerve and the inferior alveolar vein. The anatomy and variations of the human mandible are very important for planning various surgical measures such as extraction of the third molar, dental implants and mandibular reconstruction. This study was conducted to determine the frequency of the different courses of the mandibular canal  and to investigate the visibility of the mandibular canal by panoramic radiography, among a sample of Yemeni adults. Subjects and Methods: A retrospective cross-sectional study was conducted in Sana'a city on a sample of Yemeni adults. The study consisted of panoramic radiographs of 928 patients; the number of males was 340 (36.6%) and 588 females (63.4%). The mandibular canal course, as shown in the panoramic radiographs, was classified into four types: elliptical, linear, turning curves and spoon-shaped. The visibility of this canal from the first to the third molar region was assessed through visual determination of whether the lower canal was clearly visible, possibly visible, or invisible. Results:   Elliptical curves were the most observed along the mandibular canal course at 62.2% of the total, followed by the linear curve (24.8%) while the lower rate curve spoon (7.9%) and the turning curve (5.2%). There were no statistically considerable differences between the distribution of the mandibular canal courses between males and females except in the spoon curve where the ratio was 10.8% in males versus 6.1% in females (p <0.05). The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves (49.9% in the first molar, 63% in the second, 78.1% in the third molar) and the lowest among the linear curves (10.9% in the first, 18.7% in the second and 33.5% in the third molar). On panoramic radiographs, the invisible mandibular canals are found in 198 (21.3%) of the examined sites in the first molar region, in 85 (11%) in the second molar region, and in only 6 (0.64%) in the third molar region. Conclusion:  It was observed that elliptical curves along the path of the mandibular canal were the most present, while a decrease in the ratio of the two types of spoon curve and turning curve was observed. It was found that spoon curve was significantly more common among males than females. It was also found that the visibility of  madibular canal is fewer in the first molar region than in the third molar region.                Peer Review History: Received: 21 September 2020; Revised: 8 October; Accepted: 29 October, Available online: 15 November 2020 Academic Editor: Dr. Sally A. El-Zahaby, Pharos University in Alexandria, Egypt, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:                Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Dr. Sunita Singh, Baylor College of Medicine, Houston, Texas, USA, [email protected] Dr. Ali Abdullah A. Al-Mehdar, Thamar University, Yemen,  [email protected] Similar Articles: BIOFILM FORMATION AND ANTIBIOTIC SUSCEPTIBILITY OF UROPATHOGENS IN PATIENTS WITH CATHETER ASSOCIATED URINARY TRACT INFECTIONS IN IBB CITY -YEME

SERO-PREVALENCE OF HEPATITIS C VIRUS AMONG DENTAL CLINIC WORKERS IN SANA’A CITY- YEMEN AND THE RISK FACTORS CONTRIBUTING FOR ITS INFECTION

Objectives: Dental clinic workers (DCWs) in Yemen have an additional risk of getting infected with HCV from their work place and till now there is no study in prevalence of HCV infection and associated risk factors among DCWs. The purposes of this survey were to evaluate what proportion of dentists and dental assistants had serological evidence of current or previous HCV infection, what were their risk factors for exposure, and what was the frequency of use and effectiveness of barrier methods to prevent HCV infection. Methods: Data were acquired from a cross sectional survey conducted among DCWs in 2014 at the Faculty of Dentistry, Sana’a University, in Sana'a city. A proportionate to size random sample was drawn per DCW category. A structured questionnaire was used to collect data about socio-demographic characteristics and risk factors. ELISA was used to test sera for HCV antibodies.  Results: The study included 246 dentists and 263 dental assistants; the sero-prevalence of current hepatitis C virus infection was 1.6%. Prevalence of needle stick injuries, exposure to skin and to mucous membranes were 45.6%, 26.5% and 25.3% respectively. Cuts were also common with 41.1% of participants reporting a cut in a period of one year preceding the survey. There was a highly significant associated with risk of HCV infection with needle stick injuries (OR=8.6, P=0.01, cuts (OR=4.4, P=0.04), contact with blood/saliva in skin (OR=20.8, P<0.001). But longer duration in service was not significantly associated with risk of infection (OR=2, P value=0.34).  Conclusion: In conclusion, the prevalence of HCV infection was high among Yemeni DCWs and eexposure to potentially infectious body fluids was high which might lead to high rate of transmit HCV to DCWs, therefore ensures a safer work environment is important in control and prevention of HCV in DCWs in Yemen.                 Peer Review History: Received 5 September 2017;   Revised 9 October; Accepted 1 November, Available online 15 November 2017 Academic Editor: Dr. Ali Abdullah Al-yahawi, Al-Razi university, Department of Pharmacy, Yemen, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:        Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.5/10 Reviewer(s) detail: Dr. Razan Hani Amin Haddad, Jordan University of Science and Technology, Jordan, [email protected] Dr. Tanveer Ahmed Khan, Hajvery University, Lahore, Pakistan, [email protected] Similar Articles: SERO-EPIDEMIOLOGICAL STUDY OF HEPATITIS B, C, HIV AND TREPONEMA PALLIDUM AMONG BLOOD DONORS IN HODEIDA CITY- YEMEN  PREVALENCE AND GENOTYPING OF HEPATITIS C VIRUS IN HEMODIALYSIS PATIENTS AND EVALUATION OF HCV-CORE ANTIGEN TEST IN SCREENING PATIENTS FOR DIALYSIS IN SANA'A CITY, YEME

ORAL C. ALBICANS COLONIZATION AND NON-CANDIDA ALBICANS CANDIDA COLONIZATION AMONG UNIVERSITY STUDENTS, YEMEN

Objectives: Candida albicans is diploid yeast that in some circumstances may cause oral or oropharyngeal infections. This investigation aimed to study the oral C. albicans colonization (OCC) and Non-Candida albicans Candida colonization (ONCACC) and risk factors of OCC in healthy University students.   Methods: This cross sectional laboratory study was carried between January 2014 and July 2014. A total of 265 healthy students were included in this study, 131 males and 134 females. Demographic and clinical and risk factor variables were registered in predesigned questionnaire. Standard methods were used for collection oral specimens, culturing and identifying Candida species. Results: The crude rate of OCC was 17.7% and the crude rate of ONCACC was 29.1%. C. tropicalis and C. glabrata were the most common species isolated after C. albicans. Statistically significant association of OCC (< 0.05), was identified between the gender (male) (OR=3.7), smoking (OR=14.6), denture wearing (OR=6.2), dental bridge (OR=5.4), orthodontics (OR=2.5), the reduced saliva flow rate (OR=11.3), previous antibiotics users (OR=2.99), and Qat chewers (OR=5.2). Conclusion: Current study results are important for the development of strategies to eliminate these indicators of risk and significantly reduce Candida species colonization and oral Candida infections in young healthy adults and in general in Yemen community. The data also suggests that the prevalence rate of OCC was relatively high and it was affected by presence of prostheses, orthodontics, behaviors, xerostomia certain sociodemographic characteristics, which indicate the need for comprehensive, scheduled programs of healthcare educations. Peer Review History: Received 5 October 2017;   Revised 29 October; Accepted 4 November, Available online 15 November 2017 Academic Editor: Dr. Amany Mohamed Alboghdadly, Princess Nourah bint abdulrahman university, Riyadh, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:        Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.5/10 Reviewer(s) detail: Dr. Heba-Tallah Ahmed  Mohamed Moustafa, Heliopolis University Cairo, Egypt, [email protected] Noha El Baghdady, MTI University, Cairo, Egypt, [email protected] Similar Articles: PREVALENCE AND ASSOCIATED FACTORS OF ORAL NON-CANDIDA ALBICANS CANDIDA CARRIAGE IN DENTURE WEARERS IN SANA'A CITY- YEME

Global economic burden of unmet surgical need for appendicitis

Background: There is a substantial gap in provision of adequate surgical care in many low-and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods: Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results: Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion: For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

Mortality of emergency abdominal surgery in high-, middle- and low-income countries

Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)