Marc B. Schenker, MD, MPH
The number of global transnational and internal migrants approaches 1 billion, or one-seventh of the world population. If the global migrant population constituted a nation-state, it would be the fifth largest country in the world.
TRANSNATIONAL MIGRANTS
The migration of human populations has been a constant over the course of human history. The industrialization of Europe and North America in the nineteenth and early twentieth century led to high levels of international labor migration. Over the past 50 years, the number of transnational migrants has become more than double. Since 1990, the number of migrants moving from one country to another increased by over 37% from an estimated 156 million in 1990 to over 214 million today. Currently, 3.1% of the world’s population, or one out of every 33 people, are transnational migrants. Fully half of international migrants are women.
In 2010, Europe hosted the largest number of transnational migrants, followed by Asia and North America. With 6 million international migrants, Oceania had the highest percentage of transnational migrants relative to total population, followed by North America and Europe. Some countries such as Qatar and United Arab Emirates have over 50% of their population composed of immigrants (Table 3–1).
Table 3–1. Distribution of international migrants by world region, 2010.
Ten countries hosted over 50% of all transnational migrants, with the United States hosting the largest foreign-born population of any country in the world. Six of the other top 10 countries were in Europe (Table 3–2).
Table 3–2. Countries with the highest number of international migrants, 2010.
INTERNAL MIGRANTS
The number of internal migrants, individuals who move within a country, far exceeds the global total of transnational migrants. The International Organization for Migration (IOM) estimates that there are 740 million internal migrants in the world. The number of internal migrants in China alone is nearly as large as the total number of transnational migrants in the entire world, and this trend of rural to urban migration shows no signs of slowing. China’s rapid economic growth has had a serious impact on the environment. The migration of over 200 million people to heavily polluted urban areas is likely to be significantly detrimental to health. Since many of the health issues affecting internal migrants are similar to those affecting transnational migrants, the following discussion regarding health care applies to both groups.
CAUSES OF MIGRATION
Economic Opportunity
Work and economic opportunities are currently the principal drivers of international immigration. Over half of the 214 million transnational migrants are labor migrants actively participating in the workforce, with their immediate families accounting for an additional 40% of the international migrant population.
The globalization of the world economy is not only characterized by increased flows of labor across international borders, but it has contributed to an increasingly complex pattern of international migration as well. While traditional immigration patterns persist (eg, Mexicans migrating to the United States), new ones have also emerged in the past 30 years (eg, immigrants now represent 92% of the workforce in Qatar).
Remittances sent back to countries of origin by international migrant workers exceed $400 billion each year, of which more than $300 billion goes to developing countries. The top three recipients of remittances are India, China, and Mexico. In some smaller and poorer countries, migrant remittances account for a substantial part of GDP. For example, remittances account for 46% of GDP in Tajikistan, 38% in Moldova, 35% in Tonga, and 29% in Lesotho.
In addition to being motivated by the lack of economic opportunity in their countries of origin, many migrant workers are enticed by the need for additional workers in developed countries. As populations in developed countries continue to age and retire earlier, migrant workers constitute an increasingly important part of the workforce. International migrants of working age represent 12.6% of the population aged 20–64 in the developed countries of the world, and the United Nations estimates that without international migration the working-age population in more developed regions of the world would decline by 77 million or 11% by 2050.
Education
There are an estimated 2.8 million transnational students in the world. Almost a quarter of these are Asian, with China alone accounting for around 15% of the world’s migrating students. With almost 600,000 transnational students, the United States has the most international students of any nation in the world; the European nations combined have nearly 1.2 million foreign students.
Environmental Migration
There is growing evidence that environmental disasters and other environmental effects associated with climate change (ie, severe long-term droughts and rising sea-levels) are becoming significant drivers of migration, both within countries and internationally. Current estimates predict that between 25 million and 1 billion people will be “climate refugees” by 2050.
Refugees
The United Nations estimated that 15.2 million migrants were refugees at the end of 2008, with Afghanistan (2.8 million) and Iraq (1.9 million) the source of the largest groups of refugees. Only one-fifth of the world’s refugees were located in developed nations. While migration in general is psychologically stressful, mental health problems can be greatly exacerbated for refugees.
Trafficked Workers
The trafficking of individuals for labor is a significant global problem. The International Labor Organization (ILO) estimates that globally at least 12 million people are victims of forced labor and that 20%, or 2.45 million, of these people are victims of international human trafficking. As many as 18,000 men, women, and children are trafficked into the United States each year through three main trafficking hubs: Los Angeles, New York City, and Miami.
Trafficking victims most often work either within the commercial sex industry, as domestic servants, or as forced laborers in the restaurant, agricultural, and manufacturing sectors. Regardless of the type of work, victims of trafficking are often subject to abuse that can result in physical and mental illness.
INTERNATIONAL MIGRANT WORKERS IN THE UNITED STATES
The Unites States is the leading migrant destination in the world, hosting approximately 20%, or 42.8 million, of the world’s transnational migrants. Immigrants from Mexico account for approximately 30% of the US migrant population, with another 23% coming from other Latin American and Caribbean countries. Asians are the second largest group, constituting 27% of immigrants, followed by Europeans, comprising 5%. About 30%, or almost 11 million, of the foreign-born population in the United States is irregular in status and at least 40% of this population is female.
Whether regular or irregular, immigrants constitute a growing part of the US labor force, which had approximately 23.1 million foreign-born workers in 2010. While immigrants made up 12.9% of the total population, they were a disproportionate 16.4% of the labor force. Immigrant workers in the United States are overrepresented in certain industries, with the largest numbers in hazardous industries such as agriculture, construction, and transportation.
Not all industries with large numbers of immigrants can be characterized primarily as low-wage and low-skilled. Immigrants make up over 20% of workers in the information technology and high-technology manufacturing industries. The large majority of immigrants, however, are disproportionately represented in the low-skill, low-wage sectors of the US economy. In some job categories (eg, restaurant workers and domestic help), immigrant workers make up the vast majority of the workforce (Table 3–3).
Table 3–3. Percentage of foreign-born workers disproportionately represented in select job categories in the United States, 2010.
OCCUPATIONAL HEALTH DISPARITIES
Immigrant workers are disproportionately congregated in high-risk occupations, where they are subject to hazards and exposures that can result in injury, illness, and death. Moreover, job insecurity, poverty, poor housing and diet, stress, and other social determinants adversely affect the health of immigrant workers. Job insecurity is a significant factor associated with adverse health outcomes among immigrant workers. This is particularly the case for workers who are undocumented or working in a stressful or high-risk setting.
While a large majority of migration is fully authorized by sending and receiving countries, 10–15% of today’s 214 million international migrants are “irregular” in status. Most of these migrants probably entered host countries legally, but remained beyond their authorized stays. The majority of irregular migrants of working age work as unskilled laborers in high-risk, less-desirable occupations. Uninsured and poor, irregular workers are more likely to seek health care only after long delays or in acute situations. They are at increased risk for adverse health outcomes at work.
Immigrant workers often face significant language barriers. They lack job training or work experience in many of the higher-risk jobs that are available to them. This further compounds the risks inherent in those occupations and is associated with higher injury, death, and illness rates than those experienced by native workers in the same occupations. Greater risk taking exists for many immigrant workers who may take dangerous jobs nonimmigrant workers reject.
OCCUPATIONAL INJURIES & FATALITIES
There are increased rates of occupational injuries and fatalities among foreign-born workers in most developed nations. Immigrants are more likely to experience work-related injuries in the United States. Among nonagricultural immigrant Latino workers, the average occupational injury rate is 12.2% for full-time workers, compared to an expected 7.1% rate among all low-wage, full-time workers. Work-specific studies from the agriculture, cleaning services, and garment industries all confirm that immigrants suffer from increased rates of occupational injuries and higher prevalences of chronic pain among both male and female workers.
Immigrant workers are overrepresented in high-risk occupations, but this does not completely explain why immigrant workers so often have higher injury and fatality rates than nonimmigrant workers in the same occupation. Other factors contributing to increased risk are lack of job security, lack of safety training, inadequate safety equipment, economic pressure to keep working in unsafe conditions, and language and cultural differences.
In the Unites States, where there has been an overall decrease in occupational fatalities over the past 15 years, the number of fatal injuries among Hispanic workers has nearly doubled and the rate of fatalities in this population has actually increased. Strikingly this increase in fatalities among Hispanics is entirely accounted for by foreign-born workers. Data from specific occupations further confirm the disparity in fatalities among immigrant workers. A study of construction workers, for example, found that Hispanics suffered 23.5% of construction fatalities, although they constituted only 15% of the construction workforce.
Studies conducted in Canada, Spain, France, Germany, the Netherlands, Switzerland, and Australia concluded that immigrant workers suffer from higher workplace injury and fatality rates than native workers in those countries. In contrast, studies of specific industries in Sweden and Finland found no significant difference in injury rates between native and immigrant workers.
Some studies indicate that limited host-country language proficiency plays a significant role in occupational risk. A study of occupational fatalities in Australia found that recent immigrants from non-English-speaking countries had the highest fatality rates, but that after 20 years of residence the fatality rate among long-term immigrants equaled the rate for native workers. Other studies suggest that psychological distress among immigrant workers may be a contributing factor.
WORK-RELATED ILLNESSES & CHRONIC DISEASE
Since immigrant workers are overrepresented in occupations where there are known illness and chronic disease risks, it is highly likely that immigrant workers suffer from more work-related health problems than native workers. For example, agricultural and construction laborers and cleaning service workers are at increased risk for exposures to hazardous chemicals and agents that can lead to short-term and chronic respiratory conditions and dermatological problems.
Medical conditions such as cancer, which develop over longer periods of time, are difficult to attribute to specific work conditions and exposures. This is particularly the case for immigrant workers, who are difficult to follow to evaluate long-term health outcomes. Increased cancer risk has been positively associated with a large number of occupations in which immigrant workers are disproportionately employed (Table 3–4).
Table 3–4. Illnesses and chronic diseases known or possibly associated with farm work in the United States.
SPECIAL CONSIDERATIONS FOR CLINICIANS TREATING MIGRANT WORKERS
Legal Requirements
The ILO advances conventions, protocols, and recommendations across the spectrum of work-related issues, including occupational safety and health. Few of them are adopted, and even fewer are enforced (see Chapter 2). In 2003, the United Nations adopted the International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families. Not one single migrant-receiving country in Western Europe or North America has ratified the Convention. Nonetheless, the Convention still seeks to guarantee equality of treatment and the same working conditions for migrants and nationals.
Many nations have country-specific policies and regulations regarding the provision of health care services to regular and irregular immigrants. Enforcement is inconsistent at best and ignored in most countries.
Cultural and Linguistic Competence
When providing health care to migrant workers, providers are likely to face significant language and cultural barriers. Patients in language discordant encounters, where the provider speaks a language different than that of his or her patient, face poorer health indicators, even when adjusting for socioeconomic status. A significant population of non-native language speakers necessitates having staff members who are fluent in the language of that population and familiar with cultural differences that may impact compliance with treatment recommendations.
Worker Health Profiles
A migrant worker health profile can be used to alert staff to the unique health needs of the immigrant population. This includes factors associated with increased risk of occupational injuries such as lack of safety training, absent or inadequate safety equipment, increased risk taking, oral and written communication problems, and lack of first aid for minor injuries.
Table 3–4 provides a worker health profile for farm-workers in the United States, a group that is predominantly composed of immigrant workers. It lists the known and suspected chronic disease disparities among farm workers and can serve as a model for profiles that might be developed for other job classifications that employ large numbers of immigrants.
Physical & Psychosocial Factors
Increased stress has been documented in many studies of immigrants, and may be associated with undocumented status, poverty, lack of job security, family disruption, and other factors. Health care providers need to be aware of these psychosocial factors when addressing physical factors and health among immigrant worker patients.
When to Suspect Trafficking
Health care providers are in a unique position to identify trafficked workers. Encounters in health care settings can offer opportunities to recognize and help victims of trafficking. In the United States, as many as 50% of trafficking victims receive medical care while under their trafficker’s control.
While there are no clinical or behavioral portraits of typical victims of trafficking, there are warning signs that can alert health care providers to a potential trafficking situation. These warning signs are similar to those encountered when providing care to victims of domestic violence. The following are indicators of potential labor trafficking.
• Obvious and unexplained delays in seeking care
• Evasive behavior by the patient who may fear collusion between the trafficker and the care provider
• Controlling behavior by accompanying persons who insist on being present during examinations
• Patient’s body language, affect, and attitude that may convey “victim” status
• Language barriers in which controlling accompanying person volunteers to serve as translator
• Cash payment for services and incomplete or inconsistent personal information
The following are strategies to improve identification of human trafficking victims in health care settings.
• Train health care personnel, including physicians, nurses, dentists, medical assistants, technicians, and receptionists to increase awareness of trafficking and coercion.
• Mitigate language barriers; provide professional interpreters.
• Interview and/or examine all patients privately at some point during their medical visit.
• Incorporate social, work, home history, and domestic violence screening questions into a routine intake (ie, ask patient if he/she owes an employer money).
• Carefully observe body language and communication style of patients and those who accompany them.
• Learn about local resources that can help with suspected trafficking cases.
• Call for assistance if you suspect trafficking.
CONTINUITY OF CARE FOR HIGHLY MOBILE POPULATIONS
One of the challenges in caring for immigrant workers is the lack of continuity of care. This may result from the low rates of health care received from a regular provider, or from the mobility of the immigrant worker population. Even for immigrants who do not physically change location, continuity of care may be suboptimal because of limited and variable health care encounters. When possible, immigrant workers should be encouraged to keep copies of their key health care documents. Some systems exist for collating health care records for migrants, and better systems are needed. This is a critical issue for many chronic diseases such as tuberculosis, sexually transmitted diseases (STDs), and HIV/AIDS.
All patients, including immigrant workers and their families, should have electronic health records (see Chapter 5). Educational efforts, especially those using community workers and outreach, are particularly valuable because they are done by trusted members of the community with appropriate language and cultural sensitivity.
GENERATIONAL CONSEQUENCES OF MIGRATION
Several studies have documented significant changes affecting health over a single generation. For example, cigarette smoking increased markedly among female Latin immigrants to the United States in a single generation, but the increase is not seen among men. Similar increases are seen for alcohol and drug use among female Latin immigrants. The so-called “Hispanic Reproductive Paradox” refers to the observation that immigrant Latin women have better birth outcomes for about 5 years after immigrating, after which time that differential largely disappears.
Diet can also change dramatically with immigration, often to a diet more strongly associated with obesity, diabetes, and chronic disease. The family situation is another risk modifier. Men who migrate for work without their families are at increased risk for several adverse health outcomes, including TB, STDs, violence, and drug and alcohol abuse. Awareness of these risks and behavioral changes is important for the clinician evaluating short- and long-term health risks and outcomes in the immigrant patient, and for the implementation of effective preventive strategies.
THE FUTURE
The increase in the global migrant population is expected to continue as the combined forces of economic globalization, environmental change, demographic imperatives, and the ongoing technological and social networking revolutions impel people to move. These same forces make it possible for ever larger numbers of people to migrate in search of economic opportunity and more stable and productive environments. The International Organization for Migration estimates that the number of transnational migrants will likely rise to over 400 million by 2050.
REFERENCES
Ahn R: Human trafficking: review of educational resources for health professionals. Am J Prev Med 2013;44:28 [PMID: 23415126].
Baldwin SB, Eisenman DP, Sayles JN, Ryan G, Chuang KS: Identification of human trafficking victims in health care settings. Health Hum Rights 2011;13:36 [PMID: 22772961].
Chen J: Migration, environmental hazards, and health outcomes in China. Soc Sci Med 2013;80:85 [PMID: 23273408].
Frank AL: Health care access and health care workforce for immigrant workers in the agriculture, forestry, and fisheries sector in the southeastern US. Am J Ind Med 2013;56:960 [PMID: 23532981].
ILO: Resource Guide on International Labor Migration. http://www.ilo.org/public/english/support/lib/resource/subject/migration.htm.
International Organization for Migration (IOM): http://www.iom.int/cms/home.
McCarthy AE: Spectrum of Illness in international migrants. Clin Infect Dis 2013;56:925 [PMID: 23223602].
Smith R: Immigrant workers and worker’s compensation: the need for reform. Am J Ind Med 2012;55:537 [PMID: 22457221].
United Nations: International Migration. http://unstats.un.org/unsd/demographic/sconcerns/migration/.
SELF-ASSESSMENT QUESTIONS
Select the one correct answer to each question.
Question 1: Transnational migrants
a. have doubled in number over the past 50 years
b. make up 10% of the world’s population
c. are overwhelmingly male
d. are a new phenomenon
Question 2: Internal migrants
a. are individuals who move within a continent
b. far exceed the global total of transnational migrants
c. are most common in Europe and North America
d. reflect a migratory trend from urban to rural areas
Question 3: Immigrant workers are
a. disproportionately congregated in high-risk occupations
b. less likely to be injured than other workers
c. freed from the stress of job insecurity
d. not to be confused with undocumented workers
Question 4: Migrant worker health profiles
a. can be used to alert staff to the unique health needs of the immigrant population
b. include factors associated with illness but omit occupational injuries
c. would not include factors such as lack of safety training
d. omit mention of safety equipment
Question 5: Immigrant workers are
a. less likely than other workers to develop medical conditions
b. likely to receive care for chronic medical conditions
c. low-risk candidates for occupational cancer
d. high-risk candidates for work-related medical conditions