Methodology: Antibiotic Resistance

Argentina

Aggregated data were obtained from the WHONET-Argentina Network and the SIREVA II-Argentina Network. Data were collected from 98 institutions representing all country territories. The data included information on the name of the organism, number of isolates tested, and percentage resistance for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up to date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2017.

Argentina, Australia, Bahrain, Bhutan, Bosnia and Herzegovina, Brazil, Brunei Darussalam, Burkina Faso, Cambodia, Egypt, Ethiopia, Georgia, India, Indonesia, Iran, Iraq, Japan, Jordan, Korea, Rep., Kosovo, Kuwait, Laos, Lebanon, Liberia, Libya, Macedonia, FYR, Madagascar, Malawi, Malaysia, Mali, Mauritius, Moldova, Myanmar, Nepal, Nigeria, Oman, Pakistan, Palestinian Territory, Peru, Philippines, Qatar, Russia, Saudi Arabia, Singapore, South Africa, Sri Lanka, Sudan, Switzerland, Thailand, Tunisia, United Kingdom, Zambia

Data for these countries were obtained from the Global Antimicrobial Resistance Surveillance System (GLASS) maintained by the World Health Organization (WHO). Data are collected at the national level under the responsibility of each participating country, and include data from several types of healthcare facilities (e.g., university or specialized hospitals; general and district hospitals; rehabilitation centers; nursing homes). Only invasive isolates from blood were included, and the interpreted results were based on the clinical breakpoint criteria used by the local laboratories. Sample sizes and coverage vary considerably between countries. Latest data from 2020.

Armenia, Belarus, Montenegro, North Macedonia, Serbia, Switzerland, Turkey

The Central Asian and European Surveillance of Antimicrobial Resistance Network (CAESAR) is maintained by the World Health Organization Regional Office for Europe (WHO/Europe). Data are collected at the national level under the responsibility of each participating country and include data from several types of health care facilities (e.g., university or specialized hospitals; general and district hospitals; rehabilitation centers; nursing homes). Only invasive isolates from blood and cerebrospinal fluid (CSF) were included and the interpreted results were based on the clinical breakpoint criteria used by the local laboratories. In 2020, CAESAR stopped reporting the number of isolates tested, the number of resistance isolates and the number of intermediate isolates. From 2020 onward, samples included 20 or more isolates, and the percent resistant reflects only resistant isolates and not intermediate isolatesSample sizes and coverage vary considerably between countries. Latest data from 2021.

Australia

Aggregated data were obtained from the Australian Group on Antimicrobial Resistance (AGAR). Data were collected from 26 institutions from each state and the mainland territories. The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2017.

Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden

Data for these European countries were obtained from the European Antimicrobial Resistance Surveillance Network (EARS-Net) maintained by the European Centre for Disease Prevention and Control (ECDC). Data are collected at the national level under the responsibility of each participating country, and include data from several types of healthcare facilities (e.g. university or specialized hospitals; general and district hospitals; rehabilitation centers; nursing homes). Only invasive isolates from blood and CSF were included and the interpreted results were based on the clinical breakpoint criteria used by the local laboratories, though EARS-Net encourages the use of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints. Sample sizes and coverage vary considerably between countries. Latest data from 2021.

Canada

Aggregated data were obtained from Canadian Antimicrobial Resistance Alliance (CARA), which collects data from 15 tertiary care medical centers located in 8 of the 10 provinces in Canada. The data included organism name, number of isolates tested, and percentage of resistance for selected antibiotics. Isolates collected from both pediatric and adult sources were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2014.

Chile

Aggregated data were obtained from the Chilean Society of Infectious Diseases. Data were collected from 30 hospitals. The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2014.

China

Aggregated data were obtained from the CHINET surveillance of bacterial resistance. Data were collected from 30 hospitals from 21 provinces or cities. The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2017.

Ecuador

Aggregated data were obtained from the Reference Laboratory for Antimicrobial Resistance at the National Institute of Public Health Research (INSPI). The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2014.

Ghana, Zimbabwe

Aggregated data were obtained from Lancet Laboratories. The data included organism name, number of isolates tested, and percentage resistant for selected antibiotics. Isolates from both pediatric and adult sources were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2016 (Ghana) and 2015 (Zimbabwe).

India

Antibiotic resistance data for India were obtained from SRL Diagnostics Limited, Fortis Healthcare Limited, and the Indian Council of Medical Research (ICMR). SRL Diagnostics is a private laboratory network. In 2014, the network included approximately 5,700 collection centers spread across 26 (of 29) states and two (of seven) Union Territories (UTs). The collection centers included private hospitals (tertiary and secondary care), diagnostic laboratories, and home collection agencies. Culture specimens collected were transported to the nearest of four reference laboratories located in four different regions of the country for isolation, organism identification, and antimicrobial susceptibility testing. For each specimen, the following information was obtained: (1) final blood culture result (positive growth or no growth); (2) the identified organism, if culture was positive; (3) the interpreted results for tested antimicrobials (susceptible, intermediate-resistant, or resistant); (4) patient identifier and demographic information (age and gender); (5) collection center information (name of the center, city, and state); and (6) the date of specimen collection. Organism identification and antimicrobial susceptibility testing were performed using broth microdilution methodology (MicroScan® panels, Siemens, Sacramento, CA) in all four reference laboratories. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Seventy-nine percent of positive cultures were contributed by 20 collection centers, which are private tertiary care hospitals located in seven major cities in six states and one UT. Only data on invasive isolates from blood and cerebrospinal fluid were included in this data. The data include isolates from all age groups.

Fortis Healthcare Limited is a private hospital network, which includes 12 hospitals. Isolate level data were obtained from 12 hospitals located in various cities across India within this network. The data included all pathogens isolated from blood and cerebrospinal fluid in 2012. For each specimen, the following information was obtained: (1) the identified organism if culture was positive; (2) the interpreted results for tested antimicrobials (susceptible, intermediate-resistant, or resistant); (3) patient identifier; (4) the dates of specimen collection and date of susceptibility testing; and (5) patient location (ward or intensive care unit). Information on patient gender and age were not available. However, data included specimens collected from both pediatric and adult patients. Categorical result interpretations were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing.

Data obtained from the Indian Council of Medical Research (ICMR) AMR surveillance network included four tertiary care hospitals. The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Specimens from pediatric and adult patients were included, but not differentiated. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2017.

Kenya

Isolate level data for Kenya were obtained from a private tertiary care teaching hospital. The data included all pathogens isolated from blood and cerebrospinal fluid in 2012. For each specimen, the following information was obtained: (1) the identified organism if culture was positive; (2) the interpreted results for tested antimicrobials (susceptible, intermediate-resistant, or resistant); (3) patient identifier; (4) the dates of specimen collection and date of susceptibility testing; and (5) patient location (ward or intensive care unit). Information on patient gender and age were not available. However, data included specimens collected from both pediatric and adult patients. Categorical result interpretations were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2015.

Malawi

Aggregated data were obtained from a surveillance study of blood cultures routinely taken from adult and paediatric patients with fever or suspicion of sepsis admitted to Queen Elizabeth Central Hospital in Blantyre, Malawi from 1998 to 2016. The hospital serves an urban population of 920,000 in 2016, with 1,000 beds, although occupancy often exceeds capacity. The hospital admits about 10,000 adults and 30,000 children each year. Antimicrobial susceptibility tests were done by the disc diffusion method according to British Society of Antimicrobial Chemotherapy guidelines. For more details see: Musicha et al. (2017) "Trends in antimicrobial resistance in bloodstream infection isolates at a large urban hospital in Malawi (1998-2016): a surveillance study" The Lancet Infectious Diseases 17(10):1042-1052. Latest data from 2017.

Malaysia

Aggregated data were obtained from National Surveillance of Antimicrobial Resistance, Malaysia. Data were collected from 41 hospitals distributed in 13 states of Malaysia. Data were available only if at least 30 isolates were tested for resistance for a specific bug-drug combination The data included information on the name of the organism, number of isolates tested, and percentage resistance for selected antibiotics. Specimens from both pediatric and adult patients were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up to date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2017.

Mexico

Aggregated data were obtained from Hospital Civil de Guadalajara "Fray Antonio Alcalde". The data included information on the name of the organism, number of isolates tested, and percentage resistance for selected antibiotics. Specimens from both pediatric and adult patients were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up to date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2015.

New Zealand

Aggregated data for New Zealand were obtained from the Public Health Surveillance Program. Data were collected from 25 hospital and community laboratories. The data included information on the name of the organism, number of isolates tested, and percentage resistant for selected antibiotics. Data were available only if at least 100 isolates were tested for resistance for a specific bug-drug combination. Specimens from both pediatric and adult patients were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up to date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2015.

Pakistan

Data for Pakistan were obtained from Chugtai Lab. For each specimen, the following information was obtained: the identified organism; the interpreted results for tested antimicrobials (susceptible, intermediate-resistant, or resistant); demographic information (age and gender); the date of specimen collection. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Only data on invasive isolates from blood and cerebrospinal fluid were included in this data. The data include isolates from all age groups. Latest data from 2017.

South Africa

Isolate data data were obtained from both the public and private sectors representing almost the entire health facilities in the country. Public sector data were obtained from the National Health Laboratory Service (NHLS) and private sector data were obtained from South African Society for Clinical Microbiology (SASCM). SASCM collates data from four private-sector reference laboratories (Ampath, Lancet, Vermaak and Partners, Pathcare) representing all regions of the country. The following pathogens were included in the NHLS and SASCM data: E. coli, Klebsiella pneumoniae, Acinetobacter baumannii complex, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter cloacae complex, Enterococcus faecium/faecalis. Isolates from both pediatric and adult sources were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. All laboratories have an External Quality Assurance program for quality checks and all private laboratories and the majority of NHLS laboratories are SANAS (South African National Accreditation Society) accredited. Data were omitted for those hospitals that tested less than 30 ESKAPE pathogens for a particular antimicrobial agent. Latest data from 2016.

Taiwan

Aggregated data were obtained from the Taiwan Nosocomial Infection Surveillance (TNIS) and compiled by The National Health Research Institutes, Taiwan. The TNIS, launched by Taiwan CDC, collects data on nosocomial infections in all hospital ICUs in Taiwan, including antibiotic resistance. Specimens from pediatric and adult patients were included, but not differentiated in this website. The breakpoint of each antibiotic in a given year may vary among hospitals, depending on how quickly the hospital updates breakpoint information following annual revisions of the CLSI. The detailed description is in https://infection.nhri.org.tw/?page_id=337. Latest data from 2016.

United States of America

Data for the United States was obtained from The Surveillance Network (TSN), the Center for Disease Control and Prevention's National Healthcare Safety Network, and ResistanceMap Surveillance Network. Isolate level data was obtained from The Surveillance Network (TSN) for the years 1999-2012. TSN is an electronic repository of antimicrobial drug susceptibility data from a national network of >300 microbiology laboratories in the United States. Participating laboratories are geographically dispersed and make up a nationally representative sample based on patient population and number of beds. Patient isolates are tested on site as part of routine diagnostic testing for susceptibility to different antimicrobial agents by using standards established by the Clinical and Laboratory Standards Institute (CLSI) and approved by the US Food and Drug Administration (FDA). Results are then filtered to remove repeat isolates and identify microbiologically atypical results for confirmation or verification before being included in the TSN database. Data from the database have been used extensively to evaluate antimicrobial drug resistance patterns and trends (see references). CDC's National Healthcare Safety Network is a healthcare-associated infection (HAI) tracking system. Hospitals provide data and antimicrobial susceptibility information to the CDC regarding hospital-acquired infections for a selected group of pathogens. ResistanceMap Surveillance Network (RSN) is an isolate-level surveillance system that obtains antimicrobial drug susceptibility data from a network of hospitals across the United States. Patient isolates are tested on site as part of routine diagnostic testing for susceptibility to different antimicrobial agents by using standards established by the CLSI and approved by the US FDA. Results are then filtered to remove repeat isolates. Latest data from 2016.

Venezuela

Aggregated data were obtained from PROVENRA. Data were collected from 51 institutions. The data included organism name, number of isolates tested, and percentage resistant for selected antibiotics. Isolates from both pediatric and adult sources were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2013.

Vietnam

Aggregated data were obtained from 16 hospitals, which are part of the VINARES project, for a one-year period (November 2012 to October 2013). For selected pathogens of interest, the data included information on organism name, number of isolates tested, percentage resistant for selected antibiotics, and 95% confidence intervals for resistance rates. Specimens from both pediatric and adult patients were included. Categorical result interpretations ("susceptible", "intermediate", and "resistant") were based on up-to-date Clinical Laboratory Standards Institute (CLSI) criteria at the time of testing. Latest data from 2016.

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