Figure: Drivers of AMR

AMR occurs naturally over time, usually through genetic changes. AMR organisms are found in people, animals, food, plants, and the environment (in water, soil, and air). They can spread from person to person or between people and animals, including from food of animal origin. The main drivers of antimicrobial resistance include the

• Misuse and overuse of antimicrobials
• Lack of access to clean water, sanitation, and hygiene (WASH) for both humans and animals
• Poor infection and disease prevention and control  (IPC) in healthcare facilities and farms
• Poor access to quality, affordable medicines, vaccines, and diagnostics
• Lack of awareness and knowledge; and lack of enforcement of legislation. 

Misuse and overuse of antimicrobials

The problem of AMR in low- and middle-income countries (LMICs) is less documented partly due to limited resources affecting their diagnostic capacities (Gahamanyi et al., 2020). This leads to the use of broad-spectrum antibiotics (like third generation of cephalosporins) for minor infections or without determining the disease aetiologies (Jansen et al., 2018). A recent study in 14 countries of Sub-Saharan Africa (SSA) showed that only 1.3% of laboratories carry out bacteriology testing underlining insufficient laboratory capacity leading to misuse of antibiotics (Africa CDC, 2022). In 2019, the SSA and South Asia were the predominant regions that experienced increased mortality rates associated with AMR (Murray et al., 2022). 

The overuse of antibiotics, especially taking antibiotics when they’re not the correct treatment, promotes AMR. According to the Centers for Disease Control and Prevention, about one-third of antibiotic use in people is not needed nor appropriate. Antibiotics treat infections caused by bacteria and not viral infections. For example, an antibiotic is the correct treatment for strep throat, which is caused by bacteria. But it is not the right treatment for most sore throats, which are caused by viruses. Where antimicrobials can be bought for human or animal use without a prescription, the emergence and spread of AMR is made worse. Examples of misuse include (i) taking antibiotics for viral infections such as colds and flu, (ii) using them without prescription, (iii) sharing them with your relatives or colleagues, (iv) not following the prescription guidelines (for instance taking an antibiotic once a day instead of twice a day or 5 days instead of seven days), (v) not completing the prescribed dose, (vi) using them as animal growth promoters on farms or in aquaculture, etc.

Limited access to clean water, sanitation and hygiene (WASH)

Healthcare facilities are crucial in reducing disease but the lack of basic WASH services contributes to more infections, extended hospitalizations, and preventable deaths, including of mothers and babies. Infection prevention and control (IPC) by improving WASH is one of five objectives in the World Health Organization’s (WHO) Global Action Plan on AMR (Sano et al., 2020). The WHO and the United Nations Children’s Fund (UNICEF), through the Joint Monitoring Programme (JMP), are responsible for global monitoring of the Sustainable Development Goal (SDG) targets for WASH (Bain et al., 2018). WASH is essential on battlefronts for reducing and controlling the rise of AMR. Poor sanitation and hygiene lead to infections that promote extensive use of antimicrobials. Therefore, this promotes AMR due to the pressure on pathogens.  Providing WASH and improving wastewater systems will lead to a major decline in infection and AMR pathogens around the world. The lack of WASH may account for much of the AMR spread in  LMICs and beyond health facilities (Prendergast et al., 2019).

Wastewater and sludge from animals, humans, and plants are overloaded with AMR pathogens and antimicrobial residues that contaminate water bodies (Kraemer et al., 2019). This could result in the spread of AMR microorganisms, thus increasing the risk of human exposure to AMR pathogens. The effectiveness of hygiene has a significant impact on lowering infection rates and the need for antimicrobial treatment and thus,  reducing the spread and development of AMR (Essack, 2021). A previous study conducted in Guatemala showed that improved hygiene was associated with a 30–50% decrease in odds of detecting resistance to all antimicrobials (Ramay et al., 2020). Ramay et al. (Ramay et al., 2020) found that for nine out of ten antibiotics, the odds of detecting resistant bacteria decreased by ~ 32% (odds ratios, OR 0.53–0.8, P< 0.001) for every unit of improvement of a hygiene scale. Therefore, improving the quality of drinking-water, sanitation systems, and treatment of wastewater and sludge are needed.

Poor infection and disease prevention and control  (IPC) in health-care facilities

The spread of infections constitutes a global health threat, with concerns in developing countries making prevention and control of infections a critical action for a well-functioning health system. The African region is not well equipped nor has effective means compared with international standards of IPC to combat the emergence and re-emergence of infectious diseases. This has been seen with the current Covid-19 pandemic. 

Today, healthcare-associated infections (HCAI), often called nosocomial infections, affect a large number of patients globally, elevating mortality rates and financial losses significantly. According to estimates reported by the WHO, approximately 15% of all hospitalized patients suffer from these infections. These infections account for 4%–56% of all death causes in neonates, with an incidence rate of 75% in South-East Asia and Sub-Saharan Africa. The incidence in high-income countries ranges between 3.5% and 12%. HCAI and other emerging infectious diseases require a strengthened health system, with the availability of standard infrastructure and equipment, skilled personnel, good practices, and awareness by the general population to prevent the occurrence and spread of infectious diseases.

The rapid spread of multidrug-resistant organisms and outbreaks of highly infectious diseases has been associated with the need to imperatively pay particular attention to infection, prevention, and control, through the adoption of and compliance to practices that guarantee patient, health care providers, visitors, and community’s safety and cost-effectiveness in health care delivery. An effective and efficient IPC program is fundamental to the quality of health care because it carries the potential benefits of reducing infection transmission in the community, public and private health care facilities, as well as in public places. Achieving this requires individual and institutional responsibility to ensure that patients, clients, visitors, or staff are not put at risk of infection or any harm during service delivery.

Poor access to quality, affordable medicines, vaccines, and diagnostics

Substandard and falsified medical products endanger health, promote antimicrobial resistance, undermine confidence in health professionals and health systems, create distrust about the effectiveness of vaccines and medicines, waste the limited budgets of families and health systems and provide income to criminal networks. Vaccines have been introduced for the prevention of several childhood diseases and eradication of some like smallpox and rinderpest (Rosini et al., 2020). Vaccination directly reduces the incidence of infectious diseases caused by both susceptible and AMR pathogens, thus preventing inappropriate use of antimicrobials. The reduced use of antimicrobials slows the pressure of developing resistance of both pathogens and normal flora. 

Although there is progress in immunization, Africa still lags behind in terms of introducing new vaccines and eliminating vaccine-preventable diseases (VPDs) (Amponsah-Dacosta et al., 2021). It is reported that 50% of the world’s unvaccinated or under-vaccinated children are in Africa (Stoop et al., 2021). In SSA, delays in immunization also compromise efforts of preventing morbidity and mortality associated with infectious diseases. For instance, 63% of children in SSA missed the first dose of measles vaccines (at 9 months) and the majority of these cases were reported from mothers with limited literacy (Janusz et al., 2021). Apart from education status, the distance of households from clinical settings, the vaccine supply chain, poverty, and the training of healthcare workers have also been highlighted as factors contributing to incomplete immunization.

Efforts toward equitable access to vaccines are needed to reduce both the morbidity and mortality of VPDs. It is assumed that Africa consumes 25% of the world’s vaccines but only 1% of them are manufactured in Africa. This creates a dependency on external support and hampers the control of infectious diseases. However, efforts to reverse the trend are ongoing and there is a target to reach 60% of vaccines needed by Africans to be produced on the contient (Saied et al., 2022). Initiatives of various pharmaceutical companies to establish vaccine manufacturing plants in SSA will boost immunization coverage and reduce the cost of production as such vaccines will be manufactured on the African continent. 

Lack of awareness and knowledge about AMR

One way to reduce the burden due to AMR is through promoting its awareness and designing curricula/teaching materials for different categories of people. A study in the US showed that the majority of medical students learned about antibiogram during clinical placements and 73% of them suggesting gaining formal training on antibiogram interpretation (Nand et al., 2016). A study conducted in East Africa showed that final-year medical and pharmacy students have limited knowledge of both AMR and antibiotic use in clinical scenarios (Lubwama et al., 2021). Also, the awareness of AMR threat was reported to be limited even among healthcare students in Rwanda (Majumder et al., 2020; Nisabwe et al., 2020). Nisabwe et al. (2020) reported that 96% and 83% of dental and pharmacy students heard about AMR from non-curricula sources and were unfamiliar with antimicrobial stewardship, respectively. This shows that even medical doctors and pharmacists could be less knowledgeable about AMR. In LMICs, this is worrying as final-year medical and pharmacy students are involved in prescribing or dispensing antimicrobials due to a shortage of qualified personnel (Majumder et al., 2020). 

Limited enforcement of legislation

AMR is a multi-sectoral issue requiring diverse actors to collaborate across issue areas and national borders. This is reflected in the GAP on AMR, which brings together the World Health Organization (WHO), the World Organization for Animal Health (WOAH), the Food and Agriculture Organization (FAO), and the United Nations Environment Program (UNEP) in an unprecedented attempt to build an effective AMR global governance apparatus based on a holistic ‘One Health’ approach.

Conclusion

Antimicrobial resistance (AMR) is a complex global challenge exacerbated by various factors, including the misuse and overuse of antimicrobials, inadequate water, sanitation, and hygiene (WASH), poor infection prevention and control (IPC) measures, limited access to quality medicines and vaccines, insufficient knowledge and awareness, and weak enforcement of legislation. These drivers are particularly concerning in low- and middle-income countries (LMICs), where diagnostic capacities are limited, leading to inappropriate use of broad-spectrum antibiotics. The spread of AMR is further compounded by poor WASH and IPC practices, substandard medicines, and insufficient vaccine coverage. Addressing AMR requires a multi-faceted approach, including improving WASH infrastructure, enhancing diagnostic capabilities, promoting equitable access to quality medicines and vaccines, strengthening healthcare systems, and fostering awareness and education on antimicrobial stewardship. Coordinated global efforts involving key stakeholders such as WHO, FAO, WOAH, and UNEP, guided by the ‘One Health’ approach, are crucial to mitigate the rising threat of AMR and ensure sustainable health outcomes.