Antimicrobial resistance occurs when microorganisms resist the effects of medications, making infections harder to treat and increasing the risk of disease spread, severe illness and death. Combatting antimicrobial resistance is a global priority that needs coordinated action across all government sectors and levels of society.
HIV drug resistance is caused by changes in the genetic structure of HIV that affects the ability of drugs to block the replication of the virus. Minimizing the emergence and transmission of HIV drug resistance is a vital part of global efforts to address antimicrobial resistance.
Department information note
Over the past decade, the world has witnessed unprecedented scale-up of antiretroviral therapy (ART), which has saved the lives of tens of millions of people. As of December 2019, 25.4 million people out of an estimated 38 million people living with HIV were receiving ART globally. An increased use of HIV medicines has been accompanied by the emergence of HIV drug resistance, which has also steadily increased in recent years.
If not prevented, resistance can jeopardize the efficacy of antiretroviral drugs, as shown by a newly published systematic review and meta-analysis. Resistance is also associated with an increased number of HIV infections and HIV-associated cases and deaths.
To coordinate the global effort to protect the long-term efficacy of HIV medicines, WHO, in collaboration with HIVResNet, a global HIV resistance network, developed an HIV drug resistance prevention and assessment strategy. The strategy provides an overview of WHO-recommended actions at the country level to combat unnecessary emergence and transmission of drug-resistant HIV.
The 2020 updated HIV drug resistance strategy – which is to be released before the end of the year – considers lessons learned in the field over the last decade and anticipates the ongoing scale-up of antiretroviral therapy and HIV pre-exposure prophylaxis in low- and middle-income countries during an era of transition to dolutegravir-based regimens.
The foundation of WHO’s recommendation is the development, by countries, of a 5-year national action plan on HIV drug resistance, which is aligned with the 5 key pillars of the Global action plan on HIV drug resistance:
- prevention and response,
- monitoring and surveillance,
- research and innovation,
- laboratory capacity, and
- governance and enabling mechanisms.
The Global HIV Drug Resistance Global Action plan mirrors and is interlinked with the Global action plan on antimicrobial resistance.
Standardized surveillance of HIV drug resistance provides countries with actionable evidence that is used to optimize patient and population-level treatment outcomes. The surveillance of pretreatment HIV drug resistance (drug resistance present in the virus of people starting or re-starting antiretroviral therapy) informs the national choice of recommended first-line antiretroviral regimens. WHO has developed survey methods to monitor pretreatment HIV drug resistance among adults and infants.
WHO has just released the guidance on HIV drug resistance surveillance in countries scaling up pre-exposure prophylaxis (PrEP). While it is universally expected that HIV infection will be an infrequent event among populations taking pre-exposure prophylaxis to prevent HIV infection, drug-resistant HIV can emerge in the very small number of people who may become infected while taking PrEP. This can negatively impact the effectiveness of available antiretroviral treatment options due to the use of the same drugs for both prevention and as components of recommended first-line antiretroviral therapy.
Countries implementing HIV drug resistance surveys are encouraged to perform HIV drug resistance testing at laboratories designated by WHO for the purpose of performing HIV drug resistance testing for surveillance.
Map: WHO HIV drug resistance laboratory network
These laboratories are members of the WHO HIVResNet and function under the WHO HIV drug resistance Laboratory Operational Framework. This second edition, just published in 2020, reflects recent technical and strategic developments, including consideration of next-generation sequencing methods, updates to standard operating procedures and quality assurance of HIV sequences such as the integrase gene and assay validation recommendations. The recommended specimen types for HIV drug resistance genotyping are plasma or dried blood spots. Dried blood spots should be used for HIV drug resistance surveys in which plasma cannot be handled as per WHO recommendations. The WHO manual for HIV drug resistance testing using dried blood spot specimens, third edition just published in 2020, emphasises best practices for dried blood spots preparation, storage and shipping, as well as selection of appropriate positive controls.
WHO’s HIV drug resistance report 2019 showed substantial progress in the surveillance of HIV drug resistance. Between 2004 and 2020, 57 countries implemented surveys of HIV drug resistance using WHO-recommended methods (see map below), and 17 countries have plans to conduct surveys. Countries are strongly encouraged and supported in their efforts to promptly interpret, disseminate and use HIV drug resistance survey data at national and global levels to inform treatment policy choices and to advocate for strong HIVDR prevention and response efforts.
Map of countries implementing national HIV drug resistance surveys, 2004–2020
Join us for a webinar on “Addressing HIV drug resistance to protect the effectiveness of HIV treatment in celebration of World Antimicrobial Awareness Week 2020 on 20 November from 14:00 to 15:30 CET (Amsterdam, Berlin, Rome, Stockholm, Vienna time)
The webinar will cover WHO’s strategy to monitor and response to HIV drug resistance, latest global epidemiological data, new surveillance methods, and most recent data on resistance to new ARV medicines used for HIV treatment and prophylaxis.