Frequently asked questions on antimicrobial resistance
Q: Why has this happened now?
A: In just the past few decades, the development and spread of resistant microbes has been greatly accelerated by several concurrent trends. These have worked to increase both the number of infections and the spread of infections from person to person, thus creating an increased need for antimicrobials.
Q: What are some of these trends?
A: Important trends include urbanization with its associated overcrowding and poor sanitation; pollution, environmental degradation and changing weather patterns, which can affect the incidence and distribution of infectious diseases; and a growing proportion of elderly people needing hospital-based treatments and thus at risk of exposure to highly resistant pathogens found in hospitals.
Additional trends include the AIDS epidemic, which has greatly enlarged the population of immunocompromised patients at risk of opportunistic infections, and the resurgence of old foes such as malaria and tuberculosis, causing millions of infections each year. The enormous growth of global trade and travel means that a resistant microbe can spread from its place of origin to almost anywhere else in the world within 24 hours.
Q: What is the most important cause of resistance?
A: Although the natural phenomenon by which resistance emerges can be accelerated and amplified by a variety of factors, the most important cause is the inappropriate use of antimicrobials.
Q . What constitutes “inappropriate” use of antimicrobials?
A . Inappropriate use occurs when antimicrobials are taken for too short a time, at too low a dose, at inadequate potency, or for the wrong disease. Both overuse, such as through the over-prescribing of antimicrobials, which tends to occur in wealthier nations, and underuse through lack of access, inadequate dosing, poor adherence, and poor quality drugs, play a role. For example, in some developing countries, antimicrobials can be purchased in single doses without a prescription. Economic hardship means that many patients will stop taking an antimicrobial as soon as they feel better, which may occur before the microbe has been eliminated.
Q: Are other economic factors involved?
A: Yes. When infections become resistant to firstchoice, or “first-line” drugs, treatment has to be switched to second- or third-line drugs, which are often more expensive and may not be available in some settings. For example, the drugs needed to treat multidrug-resistant forms of tuberculosis are over 100 times more expensive than the first-line drugs used to treat non-resistant forms.
In many countries, the high cost of such replacement drugs is prohibitive, with the result that some diseases can no longer be treated in areas where resistance to first-line drugs is widespread. In addition to the cost of drugs, patients infected with resistant microbes often remain sick longer, which increases the costs of health care and is an added financial burden to the family and to society.
Q: Does this mean that only those populations living in developing countries are threatened by resistance?
A: No. Antimicrobial resistance is a global problem requiring a global solution. No single nation, however effective it is at containing resistance within its borders, can protect itself from the importation of resistant pathogens through travel and trade. Poor prescribing practices in any country now threaten to undermine the effectiveness of vital antimicrobials everywhere.