Migration has gained significant prominence in today’s world. It is currently estimated that close to 1 billion people are on the move today than at any other time in recorded history, where close to 244 million are international migrants (UNDESA, 2014) and 740 million are internal migrants (IOM, 2015). Now more than ever, particularly with the advent of globalization, mass population movement is occurring at an unprecedented rate driven by a myriad of factors including but not limited to insecurity, conflict, political instability, shifts in climate or environment, natural/man-made disasters, and more universally, the search for or promise of better economic prospects and livelihood opportunities.
2015 saw the highest levels of forced displacement recorded globally including refugees, asylum-seekers and internally displaced persons from Africa, the Middle East and South Asia with the world hosting approximately 15.6 million refugees by mid-2015.
Population Movement, Health, EIDs and AMR
Conditions surrounding the migration process can often fuel health inequities and expose migrants to increased health risks rendering migrants more vulnerable to negative health outcomes. Further exacerbating this are restrictive migration policies and anti-migrant sentiments which limit migrant access to healthcare, education (including health information) and safe working and living conditions. In this context, migration should be recognized as a social determinant of the health of migrants. Migrants and mobile populations also face numerous obstacles inn accessing essential healthcare services due to a number of factors including irregular immigration status, lack of documentation, language/cultural barriers, a lack of migrant-inclusive health policies and inaccessibility of such services, usually as a result of poverty and/or unemployment.
Increased cross-border and cross-continental movement of people can influence the transmission of infectious disease and the development of antimicrobial resistance. The conditions that may lead to mass migration in the first place can lead to the breakdown of public health infrastructure and poor provision of shelter, a lack of safe drinking water, sanitation and food insecurity as a result of poverty. Furthermore, the migration process in itself can present extreme psychological and physical challenges and subsequently increase risk of the spread of infection if migrants are malnourished, have inadequate water and sanitation or are living in overcrowded settlements. This can lead to unregulated and/or inappropriate use of antibiotics or medication, which can contribute to the emergence and spread of drug resistance. On arrival at destination points, migrants are susceptible to a range of infectious diseases such as tuberculosis and other respiratory infections, for example. In addition, migration may bring people into contact with new microbes and vectors, result in changes in behavioral patterns, all of which can influence risk of infection and transmission of disease.
International migration, in particular, can affect health outcomes in migrant source, transit and recipient countries. It remains an underlying factor in the emergence of infectious disease threats and must be carefully managed, as outbreaks and EIDs incidents such as cholera and yellow fever outbreaks, the Ebola epidemic and concerns around MERS-COV have shown. The flow in and out of countries where health determinants and outcomes may differ creates situations whereby `locally defined public health threats and risks assume international or global relevance’.
Population mobility also contributes to the distribution of antimicrobial drug-resistant organisms which poses a major risk in the spread of drug resistance threatening the ability to effectively control and manage the transmission of infectious disease. Antimicrobial resistance (AMR) is a growing threat to global public health in its different forms i.e. multi-drug resistant TB (MDR TB), malaria/influenza/HIV resistance etc. Left unaddressed, AMR can undermine progress towards and endanger achievement of the Sustainable Development Goals 2030. AMR can occur for a variety of different reasons including reduced adherence to drug therapies, suboptimal dosing, interrupted treatment or defaulting, diagnostic or laboratory errors, and resistance (innate or acquired). Mobile population importation of drug-resistant infections can also be more evident where the incidence or prevalence of the infection or disease is either low or absent and therefore, there are a number of examples of imported multi-drug resistant infectious diseases associated with migrant or mobile populations moving from hyper-endemic to non-endemic areas e.g. MDR TB and MDR Plasmodium falciparum malaria.6 Thus, there are several complex considerations in the issues surrounding AMR and EIDs in the context of human mobility. Local, regional and global human mobility is a complex and dynamic trend which can amplify the spread of communicable disease, result in emergence or reemergence of infectious disease and globalize public health threats.
IOM’s Health, Border and Mobility Management is a conceptual and operational framework that empowers governments and communities in the prevention, detection and early response to potential health threats across the mobility continuum (at points of origin, transit, destination and return) and at spaces of vulnerability where migrants and mobile populations are likely to interact with local and host communities. With a special focus on border areas, HBMM combines border management with health security and ultimately supports the realization and application of the International Health Regulations (2005). HBMM also endeavors to build human mobility-competent health systems at both community and primary healthcare facility level, catering to the principle of universal health coverage. HBMM is also essential for the development of public health interventions designed to prevent and respond to international health threats thereby supporting the mandate of the Global Health Security Agenda (GHSA). Understanding mobility is an essential component of evidence-based public health programming which combines information on epidemiology, burden of disease and health systems capacity with the various health risks associated with population mobility.
Adapted to the pillars of the World Health Assembly Resolution 61.17 on the Health of Migrants, the HBMM operational framework can largely be summarized as inclusive of operational research, data collection, population mobility mapping, disease surveillance, capacity building of health and border management services and partnerships, ultimately resulting in health system strengthening/preparedness and cross-border coordination.