The story

Review: Volume 5 - Travel

Whether you want to take a relaxing vacation in Asia, a backpacking journey in South America, a road trip in the USA, a cultural tour in Europe, or a safari in Africa, we've got the most inspiring and eclectic collection of hotels, guesthouses, boats, lodges, spas, and houseboats that you could ask for. Just flip through the pages of this new compilation of dreamy spots to plan your next holiday, wherever it may be. Highlights include: in Kerala, India, futuristic-looking, Star Wars-style houseboats made of bamboo poles, palm leaves, and coconut fibers; the best place for a delectable cup of joe: a luxury lodge and spa on a java plantation in (you guessed it) Java; an Ayurvedic spa in the Himalayas where nothing matters but peace and relaxation; a lush Kenyan open-walled hut fashioned from tree trunks and shielded from the sun by a sumptuous thatched roof; Gio Ponti's sleek blue and white hotel perched on the cliffs in Sorrento, Italy; an elegant auberge in Napa Valley, California where you can stay during your wine tasting tour; a historic ranch nestled in a Death Valley oasis; an adobe hotel in the Chilean desert; in Bolivia's Uyuni salt desert, a hotel built entirely of salt; and, an "ecolodge" on a natural reserve in the Amazon rain forest.

The Cambridge History of Travel Writing

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Book description

Bringing together original contributions from scholars around the world, this volume traces the history of travel writing from antiquity to the Internet age. It examines travel texts of several national or linguistic traditions, introducing readers to the global contexts of the genre. From wilderness to the urban, from Nigeria to the polar regions, from mountains to rivers and the desert, this book explores some of the key places and physical features represented in travel writing. Chapters also consider the employment in travel writing of the diary, the letter, visual images, maps and poetry, as well as the relationship of travel writing to fiction, science, translation and tourism. Gender-based and ecocritical approaches are among those surveyed. Together, the thirty-seven chapters here underline the richness and complexity of this genre.


'… this edited collection offers an accessible treatment of British and Continental travel writing. All the essays are written in straightforward prose supported by rich footnotes.'

C. L. Bandish Source: Choice

‘… an admirable volume that combines rock solid reliability with the imaginative flair needed to engage a genre so elusive, and yet so historically pedigreed, as travel writing … splendid collective project, a joy and education to read …’


[^ 1] For more information on expedite requests for adjudications of asylum applications, see the Affirmative Asylum Procedures Manual (PDF, 1.83 MB) , Section III.B. Categories of Cases, Part 7, Expeditious Processing Required, and the Affirmative Asylum Interview Scheduling webpage. Expedite requests for refugee cases should be made to the applicable U.S. Department of State Resettlement Support Center, which facilitates informing the appropriate party of the expedite request.

[^ 2] USCIS updated its policy regarding requests to expedite applications or petitions on June 9, 2021 the update became effective upon publication.

[^ 3] A timely filed request or response means a request or response that was filed by the relevant deadline the request need not be filed at the earliest opportunity. If the requestor failed to timely file a request or response, the requestor must show that such failure was due to circumstances beyond the requestor’s control.

[^ 4] For example, the requestor is gravely ill and has a critical need to travel to obtain medical treatment in a limited amount of time, or where a vulnerable person’s safety may be compromised due to a breach of confidentiality if there is a delay in processing of the benefit application. See 8 U.S.C. 1367. A benefit requestor’s desire to travel for vacation would not, in general, meet the definition of an emergency.

[^ 5] For example, an organization broadcasting in regional areas to promote democratic interests.

A history of the DSM-5 scientific review committee

This article describes the history of the Scientific Review Committee (SRC) for DSM-5 and reviews its background, procedures and deliberative processes, and conceptual/philosophical framework. The results of its work and the most important and contentious issues that arose in its efforts are reviewed. The central role of the SRC was to provide external review for all proposals for diagnostic change in DSM-5, evaluate them on their level of empirical support using objectively structured rules of evidence agreed upon in advance and make appropriate recommendations to the leadership of the American Psychiatric Association. While the creation of the SRC necessitated a great deal of additional work on the part of the SRC, the workgroups and the DSM-5 Task Force, the SRC succeeded in increasing the focus on empirical standards for nosologic change and providing a greater degree of consistency and objectivity in the DSM review process. The article concludes with recommendations, based on lessons learned, for similar efforts that might be included in future iterations of our psychiatric nosology.

Why Choose to Buy a Parlor Guitar?

So why should you choose a parlor guitar? There’s really only one good answer to this question and it may or may not be one you like:

Because you like it.

It’s that simple. Sure, it travels well and has a “vintage” feel to it. It has a full-size neck and a nice sound. But it also lacks a bit of dynamic range as well as volume.

The best thing you can do, as I stated earlier, is to give the parlor guitar and travel guitar a side-by-side comparison while you’re in the store (and here are a few tips on how to test drive your guitar in store). See which one feels best in your hands and sounds better to your ear. Unless you’re a guitar collector trying to add a certain guitar to your collection, don’t worry about the “parlor” name. Just find a guitar that you like.

‘Prisoners of History’ Review: The Use and Abuse of the Past

The Iwo Jima statue at the United States Marine Corps War Memorial in Arlington, Va.

It’s become a truism that monuments speak of the time in which they were built as well as the time that they commemorate. And that what we hear them saying changes. At moments of political upheaval, the way we choose to remember—even what we remember—can be dramatically reconfigured. Here in the U.S., not a few statues are being removed from places of honor. And around the world, we’ve seen monuments to paragons of former regimes be displaced or reduced to rubble. Some applaud this iconoclasm as a reckoning with legacies of oppression others complain of the past being canceled based upon present-day values.

Monuments to World War II, though, have been remarkably stable. So far. Even as our understanding of that terrible war has grown more complex and nuanced, cartoonish monsters have remained lodged in our historical imagination, as have the heroic efforts made to defeat them. In the U.S., where most heroes of earlier times have been cut down to size, the image of “The Greatest Generation” still stands tall in the minds of many. The British historian Keith Lowe knows all about patriotic respect for what Winston Churchill called “their finest hour.” He also knows about the hours that followed. In his books “Inferno: The Fiery Destruction of Hamburg, 1943” (2007) and “Savage Continent: Europe in the Aftermath of World War II” (2012), he focused on the massive destructiveness of the conflict. Now, in “Prisoners of History: What Monuments to World War II Tell Us About Our History and Ourselves,” he looks at the ways in which a diverse set of countries have memorialized that bloody conflict, which set the stage for the world in which we still live.

Mr. Lowe has visited monuments around the world—from Auschwitz to Volgograd to Jersey City. No art historian, he has little to say about architectural details or subtle shifts in symbolism. Nor does his book, unlike the brilliant work of James E. Young, explore the intricate ways in which public traumas are processed. What “Prisoners of History” does do—and does well—is explain why groups in each country built the monuments in the first place and how changes in politics and international relations affected interactions with them afterward.

In painting a powerful picture of the brutal Japanese invasion of China, Mr. Lowe plunges us into the horrors of the massacres and organized sexual violence in Nanjing. He also gives us a sense of how shifting political forces in communist China made memorializing this trauma possible, and how the Chinese government in the postwar years used tensions with Japan for purposes that had little to do with coming to terms with this profoundly painful past. Whether he is writing about far-flung places where he is a well-informed tourist or European cities where he has done deep research, Mr. Lowe is a confident guide who finds sources in each city to make our experience of the memorials more meaningful.

I was fascinated to read about the Russian penchant for massive memorials. Mr. Lowe’s narrative becomes even more compelling when he gets to Italy and the “more intimate” memorial to resistance fighters in Bologna. “In the 21st century,” he writes, “every nation likes to believe itself a nation of heroes but deep down, most nations are beginning to think of themselves as victims.” After all, “martyrs are untouchable.”

Other Portable Bluetooth Speakers We Tested

Simply put, the Ultimate Ears Megaboom 3 is one of the very best portable speakers you can buy. It sounds fantastic, offering powerful punch in the bass, more detail than you’d expect in the treble, and a clear and present midrange. Thanks to its balanced, “360-degree” soundstage (in which sound is designed to be distributed from all sides), we’d go so far as to say it’s arguably the top speaker for sound in its price class, with only the Charge 5 and Sonos Roam to stand as rivals.

The Megaboom 3 is also built like a tank, with a tactile, dual-tone exterior that keeps it safe from dust and water (it’s IP67 rating means it can be dunked alongside our other top picks). It’s almost actively tough, begging you to throw it like a projectile, or roll it at your friends in an attempt to take out their legs. It also has a solid app, which allows you to do things like tune EQ, connect it to other Megaboom speakers in party mode (with a freakishly large group of up to 150 possible), and even use its top button to directly call up a pre-programmed streaming service.

The Megaboom 3 is a natural choice for the best Bluetooth speaker in your arsenal, but it falls shy of the Sonos Roam in a couple of key areas. For one thing, it doesn’t have Wi-Fi or smarts like the Roam does (the Roam offers the same functionality as homebound Alexa or Google smart speaker when connected to Wi-Fi). The Megaboom 3 also can’t be used as part of a multi-speaker sound system. And while its 20 hours of battery life is massive compared to the Roam (and most other speakers), we found it lasted several hours less than advertised at medium volume.

Most notably, while the Megaboom 3 is an audio wonder, it simply isn’t all that portable. While it’s easy to move around the house or throw in the car, unlike the Roam and the Flip 5, it’s harder to fit into a backpack or purse for travel. If you’re just going to leave it in the yard for barbecues and you don’t need Wi-Fi, though, the Megaboom 3 is a killer Bluetooth speaker with sound as powerful and clear as anything you’ll find at its size.

Missing some key features

Suppose you were head-over-heels for JBL's Flip line of Bluetooth speakers, but your phone kept dying on you while you were out at the beach or on a hike. Before you run off and buy a portable battery pack, you should really take a look at the excellent JBL Charge 5.

The Charge 5 is essentially two products in one: it has the same general form factor, robust sound quality, intuitive controls, and IP67 rating as the excellent Flip 5, only it adds pass-thru USB charging. With 20 hours of battery life, the Charge 5 can keep your tunes playing for almost a full day while it simultaneously charges up your smartphone, tablet, or anything else you'd like to plug in there. Just plug your phone's charge cable into the back of the Charge 5 and you're guaranteed almost a full day of music.

It's also worth mentioning that the Charge 5 is no slouch where sound quality is concerned. It sounds even more powerful than JBL's Flip 5, providing bigger bass, solid midrange support and producing robust, enjoyable details in music and podcasts. It's big enough to provide enough volume for a small backyard get-together, but might be a bit lost in the middle of a noisy party.

The only drawback with this speaker is that you're definitely paying more for the battery-charging functionality when you compare the Charge 5 to something like the Flip 5, and if you haven't had battery problems it might not make sense to pick this one up. But it's also very unlikely that you'd regret having this functionality if you did: somebody's phone or tablet is always on its last legs, and the Charge 5 is here to pick it back up again. It's also worth mentioning that the Charge 5 is pretty bulky: that big, charge-bank-type battery needs room, and it reduces the portability here. If you're

Built-in powerbank is very useful

Not everyone will want/need the added charging feature

If you want the biggest, loudest, most party-rocking Bluetooth speaker you can buy, JBL’s Boombox 2 wrote the book on “in your face.” In all seriousness, as with many JBL speakers the Boombox 2 is immaculately designed—rounded, robust, and heavy—and it has the audio presence to match its hefty size. While many of the speakers on this list are around the size of a soda can, the JBL Boombox 2 is a… well, you see, it’s a boombox. A dyed-in-the-wool, walk-down-the-street-with-it-on-your-shoulder boombox.

There are a lot of places where a smaller, more traditional Bluetooth speaker might serve you better. We used the Boombox 2 for several weeks while waiting on other Bluetooth speakers to arrive for evaluation. As it serenaded us in our kitchen every day, we probably never set the volume to more than 50% of its maximum. This Bluetooth speaker is very, very loud—that said, it also sounds really good, featuring more than ample bass presence and good clarity across the frequency spectrum. It fills even the most cavernous rooms, easily heard over party conversation, surging ocean waves, or the buzz of nearby power tools.

It’s also rugged, dunkable thanks to an IPX7 water resistance rating, and designed with covered ports, meaning you can tote it just about anywhere (within reason). And with JBL’s “PartyBoost” feature, you can even add in additional JBL speakers (though why you’d need to, I’m not sure).

So why isn’t this the #1 Bluetooth speaker? Simply put, it’s just too much for most people, even if it’s too much of a good thing. It’s (relatively) huge, heavy, expensive, and will offer diminishing returns for casual, everyday situations. However, if you’ve got the funds and want a Bluetooth speaker that can be nuanced enough for a low-key night in and loud enough that they’ll hear it on Mars, this is the one to get.

JBL’s Clip 4 has no right to sound as good as it does. While you’ll have to limit your expectations when it comes to bass response for any speaker this size, you’ve got to limit them a lot less with this speaker than comparable models from even a few years back. And impressive sound is just one of the enticing aspects of this pint-sized dangler.

The fourth generation of JBL’s popular Clip line has improved over its predecessor in multiple ways, from a more sturdy and ergonomic handle to new rubberized dampeners on its backside to keep it from rumbling on a countertop or distorting when the bass ramps up. The speaker has more accessible control buttons as well, including rubberized front-side controls and side controls for pairing and powering on that you can identify with your fingertips. (Though a word of caution, they’re a bit easier to press accidentally, too.)

If there’s one part of the oval-shaped model we’re not crazy about, it’s the extremely loud look of the new logo which will not let you forget which brand makes this tag-along device. But that’s a small price to pay for a speaker this pocketable that sounds this good.

Getting back to the sound quality, this is one of the few speakers of its size we actually enjoy listening to. It offers relatively impressive detail for everything from jazz to podcasts, and while hip-hop will lose some luster—especially if you try to crank up the jams—it’s the perfect speaker for the shower. It also pairs well with getaways where you simply don’t want to bring something chunkier like an Ultimate Ears Megaboom or even JBL’s own Flip or Charge models.

At 10 hours, battery life isn’t incredible, but it gets you more than a day’s use and an open USB-C port makes it easy to charge. With an IP67 rating, the speaker is both dust resistant and dunkable, though it doesn’t float so you won’t want to drop it in a lake. It connects via Bluetooth 5.1 for solid connection from 30+ feet.

As for downsides, the Clip 4 doesn’t include a speakerphone like its predecessor, nor does it pair with companion speakers over an app. Its rounded edges mean you’ll also need to clip it or lay it flat, which may not always be convenient for sound dispersion.

Those quibbles aside, if you’re looking for a seriously portable speaker with good sound that won’t break the bank, you’ll have a hard time beating the Clip 4. Of course, if you want a very similar experience but would rather save a little cash, you could try to track down the older Clip 3. It sounds a fair bit tinnier than the Clip 4, but will still work well as a shower speaker if you can find it at a good discount.

Review: Volume 5 - Travel - History

Travel is a potent force in the emergence of disease. Migration of humans has been the pathway for disseminating infectious diseases throughout recorded history and will continue to shape the emergence, frequency, and spread of infections in geographic areas and populations. The current volume, speed, and reach of travel are unprecedented. The consequences of travel extend beyond the traveler to the population visited and the ecosystem. When they travel, humans carry their genetic makeup, immunologic sequelae of past infections, cultural preferences, customs, and behavioral patterns. Microbes, animals, and other biologic life also accompany them. Today's massive movement of humans and materials sets the stage for mixing diverse genetic pools at rates and in combinations previously unknown. Concomitant changes in the environment, climate, technology, land use, human behavior, and demographics converge to favor the emergence of infectious diseases caused by a broad range of organisms in humans, as well as in plants and animals.

Many factors contribute to the emergence of infectious diseases. Those frequently identified include microbial adaptation and change, human demographics and behavior, environmental changes, technology and economic development, breakdown in public health measures and surveillance, and international travel and commerce (1-4). This paper will examine the pivotal role of global travel and movement of biologic life in the emergence of infectious diseases. It will also examine the ways in which travel and movement are inextricably tied at multiple levels to other processes that influence the emergence of disease.

Travel is a potent force in disease emergence and spread (5). The current volume, speed, and reach of travel are unprecedented. The consequences of migration extend beyond the traveler to the population visited and the ecosystem (6). Travel and trade set the stage for mixing diverse genetic pools at rates and in combinations previously unknown. Massive movement and other concomitant changes in social, political, climatic, environmental, and technologic factors converge to favor the emergence of infectious diseases.

Disease emergence is complex. Often several events must occur simultaneously or sequentially for a disease to emerge or reemerge (Table 1) (6). Travel allows a potentially pathogenic microbe to be introduced into a new geographic area however, to be established and cause disease a microbe must survive, proliferate, and find a way to enter a susceptible host. Any analysis of emergence must look at a dynamic process, a sequence of events, a milieu, or ecosystem.

Movement, changing patterns of resistance and vulnerability, and the emergence of infectious diseases also affect plants, animals, and insect vectors. Analysis of these species can hold important lessons about the dynamics of human disease.

To assess the impact of travel on disease emergence, it is necessary to consider the receptivity of a geographic area and its population to microbial introduction. Most introductions do not lead to disease. Organisms that survive primarily or entirely in the human host and are spread through sexual contact, droplet nuclei, and close physical contact can be readily carried to any part of the world. For example, AIDS, tuberculosis, measles, pertussis, diphtheria, and hepatitis B are easily carried by travelers and can spread in a new geographic area however, populations protected by vaccines resist introduction. Organisms that have animal hosts, environmental limitations, arthropod vectors, or complicated life cycles become successively more difficult to "transplant" to another geographic area or population. Epidemics of dengue fever and yellow fever cannot appear in a geographic area unless competent mosquito vectors are present. Schistosomiasis cannot spread in an environment unless a suitable snail intermediate host exists in that region. Organisms that survive only under carefully tuned local conditions are less likely to be successfully introduced. Even if an introduced parasite persists in a new geographic area, it does not necessarily cause human disease. In the United States, humans infected with Taenia solium, the parasite that causes cysticercosis, infrequently transmit the infection because sanitary disposal of feces, the source of the eggs, is generally available. In short, the likelihood of transmission involves many biological, social, and environmental variables.

Historical Perspective

Human migration has been the main source of epidemics throughout recorded history. William McNeill (7), in his book Plagues and Peoples, describes the central role of infectious disease in the history of the world. Patterns of disease circulation have influenced the outcome of wars and have shaped the location, nature, and development of human societies.

Trade caravans, religious pilgrimages, and military maneuvers facilitated the spread of many diseases, including plague and smallpox. A map in Donald Hopkins' book, Princes and Peasants: Smallpox in History (8), traces the presumed spread of smallpox from Egypt or India, where it was first thought to have become adapted to humans sometime before 1000 B.C. Smallpox spread easily from person to person through close contact with respiratory discharges and, less commonly, through contact with skin lesions, linens, clothing, and other material in direct contact with the patient. Because patients remained infectious for about 3 weeks, many opportunities for transmission were available. Even in this century, until the 1970s, smallpox continued to cause epidemics. A pilgrim returning from Mecca was the source of a large outbreak in Yugoslavia in the early 1970s that resulted in 174 Yugoslav cases and 35 deaths (9). The pilgrim apparently contracted the infection in Baghdad while visiting a religious site. Because his symptoms were mild, he was never confined to bed and was able to continue his travels and return home.

For most of history, human populations were relatively isolated. Only in recent centuries has there been extensive contact between the flora and fauna of the Old and New Worlds. Schoolchildren hear the rhyme "Columbus sailed the ocean blue, in fourteen hundred ninety-two," but may learn little about the disaster brought upon the native populations of the Americas by the arriving explorers. By the end of the fifteenth century, measles, influenza, mumps, smallpox, tuberculosis, and other infections had become common in Europe. Explorers from the crowded urban centers of Europe brought infectious diseases to the New World (10), where isolated populations had evolved from a relatively small gene pool and had no previous experience with many infections (11). The first epidemics following the arrival of Europeans were often the most severe. By 1518 or 1519, smallpox appeared in Santo Domingo, where it killed one-third to half of the local population and spread to other areas of the Caribbean and the Americas (10). The population of central Mexico is estimated to have dropped by one-third in the single decade following contact with the Europeans.

Travel across the Atlantic Ocean transformed the flora and fauna of the New World as well. Some of the transported materials became important sources of food (plants), clothing, and transportation (animals). Other transfers were less welcome: Japanese beetles, Dutch elm disease, and chestnut tree fungus. A.W. Crosby, exploring these exchanges between the Old and the New Worlds, sounds a pessimistic note: "The Columbian exchange has left us with not a richer but a more impoverished genetic pool" (10).

The explorers also paid a price in loss of lives from disease. Philip Curtin (12) provides a quantitative study of "relocation costs," the excess illness and death among European soldiers in the nineteenth century when they lived or worked in the tropics. Until the most recent armed conflicts, infectious diseases claimed more lives than injuries during wars.

Plague holds a prominent place in history and remains with us today. A bacterial infection caused by Yersinia pestis, it is primarily an infection of rodents, spread by their fleas. Human infection is incidental to the maintenance of Y. pestis in animal reservoirs. Yet plague periodically has erupted in human populations, wreaking great devastation, killing millions and causing infection that can be spread directly from person to person by the respiratory route. Human population movement has been essential in the spread of plague and the dispersal of rodents and their fleas to new areas. For centuries plague spread along trade routes. It reached California by boat around the turn of this century, caused epidemic infection in San Francisco, and then spread to wildlife, where it persists today in a large enzootic focus.

Movement of People

Travel for business and pleasure constitutes a small fraction of total human movement (5,13). People migrating individually or in groups, may be immigrants, refugees, missionaries, merchant marines, students, temporary workers, pilgrims, or Peace Corps workers. Travel may involve short distances or the crossing of international borders. Its volume, however, is huge. In the early 1990s more than 500 million persons annually crossed international borders on commercial airplane flights (World Tourism Organization, Madrid, unpublished data). An estimated 70 million persons, mostly from developing countries, work either legally or illegally in other countries (14). Movement may be temporary or seasonal, as with nomadic populations and migrant workers who follow the crops. Military maneuvers worldwide employ and move huge populations. The consequences of armed conflict and political unrest displace millions. In the early 1990s, there were an estimated 20 million refugees and 30 million displaced persons worldwide (International Organization for Migration, personal communication).

Grubler and Nakicenovic estimated and plotted the average kilometers traveled daily for the French population over a 200-year period (1800-2000) and found that spatial mobility has increased more than 1000-fold (15). In the last 40 years, the size of Australia's population has doubled and the number of persons moving into and out of Australia has increased nearly 100-fold (16).

Although social, economic, and political factors push people from an area or draw them to another, environmental resources and their impact on food and water supplies are behind many conflicts leading to displacement of populations. Acute disasters, such as flooding, earthquakes, and hurricanes often force populations to seek shelter and sustenance in new lands. Chronic changes, such as drought, depletion of soil, and disappearance of fish from streams, lakes, and oceans, draw people to new territories, or, more frequently, to the fringes of large urban centers.

Another type of travel relevant to disease emergence is the shift of populations to urban areas. It is estimated that by the year 2010, 50% of the world's population will be living in urban areas. It is projected that by the year 2000, the world will comprise 24 "megacities"- sprawling metropolitan areas with populations exceeding 10 million (World Bank, UNDP, World Health Organization, unpublished data). These areas will have the population density to support persistence of some infections and contribute to the emergence of others. Many of these areas are located in tropical or subtropical regions, where the environment can support a diverse array of pathogens and vectors. Also developing are huge periurban slums, populated with persons from many geographic origins. Poor sanitation allows breeding of arthropod vectors, rodents, and other disease-carrying animals. Crowded conditions favor the spread of diseases that pass from person to person, including sexually transmitted infections. Travel between periurban slum areas and rural areas is common, paving the route for the transfer of microbes and disease. Transfer of resistance genes and genetic recombination may also occur in and spread from crowded environments of transients.

Acute disturbances, whether climatic or political, lead to interim living arrangements, such as refugee camps and temporary shelters, that provide ideal conditions for the emergence and spread of infections. Temporary living quarters often share similarities with periurban slums: crowding, inadequate sanitation, limited access to medical care, lack of clean water and food, dislocation, multiethnic composition, and inadequate barriers from vectors and animals. An example is the movement of 500,000-800,000 Rwandan refugees into Zaire in 1994. Almost 50,000 refugees died during the first month as epidemics of cholera and Shigella dysenteriae type 1 swept through the refugee camps (17).

Movement into a rural environment poses different risks and often places new rural populations in contact with pathogens that are in the soil and water or are carried by animals or arthropods (18). Some of these pathogens such as Guanarito (19) and Sabià viruses (20) in South America were only recently recognized as capable of infecting humans.

Consequences of Movement

Human migration favors the emergence of infectious diseases through many mechanisms. When people migrate, they carry their genetic makeup, their accumulated immunologic experience, and much more (Table 2). They may carry pathogens in or on their bodies and may also transport disease vectors, such as lice. Their technology (agricultural and industrial), methods for treating disease, cultural traditions, and behavioral patterns may influence their risk for infection in a new environment and their capacity to introduce disease into the new region. Their social standing and resources may affect their exposure to local infections and their access to adequate nutrition and treatment. People also change the environment in many ways when they travel or migrate--they plant, clear land, build, and consume. Travel is relevant in the emergence of disease if it changes an ecosystem. The following examples show the many ways in which migration can influence the emergence of disease in a new area.1. Humans may carry a pathogen in a form that can be transmitted, then or later, directly or indirectly to another person. The pathogen may be silent (during the incubation period, chronic carriage, or latent infection) or clinically evident. Examples include hepatitis B virus, human immunodeficiency virus (HIV), Mycobacterium tuberculosis, M. leprae, Salmonella typhi, and other salmonella. Disease may be especially severe when a pathogen is introduced into a population that has no previous exposure to the infection. How long the consequences of migration persist varies with the specific infection. The two most critical characteristics are the duration of survival of the pathogen in a potentially infective form and its means of transmission.2. Epidemic cholera in Africa spread along the West African coast and, when the disease moved inland, followed fishing and trading routes. Markets, funerals, refugee camps--events that involved migration of persons and large gatherings with close contact--helped spread the infection. With El Tor cholera, asymptomatic and mild infections can outnumber severe disease by 100 to 1 (21), thus permitting those infected to continue to move and work.3. Pilgrims carried an epidemic strain of group A Neisseria meningitidis from southern Asia to Mecca in 1987. Other pilgrims who became colonized with the epidemic strain introduced it into sub-Saharan Africa, where it caused a wave of epidemics in 1988 and 1989 (22).4. Humans may carry a pathogen that can be transmitted only if conditions are permissive. This permissiveness can pertain to human behavior, the environment, or the presence of appropriate vectors or intermediate hosts. For example, the ease with which HIV spreads in a population depends on sexual practices, condom use, the number of sex partners, and intravenous drug use, among other factors. Malaria requires specific mosquito vectors (with access to susceptible humans) to spread to new geographic regions. Schistosomiasis can be introduced into a new region only if the appropriate snail host is present and if the eggs excreted (in urine or feces, from an infected person), reach the snails in an appropriate environment.5. Humans may carry a strain of microbe that has an unusual resistance pattern or virulence genes. A multiple-drug-resistant strain of Klebsiella pneumoniae appears to have been transferred by an asymptomatic woman from a hospital in Bahrain to Oxford, where it caused outbreaks in two British hospitals (23). People also carry their background flora, in the intestinal tract, for example, which may contain plasmids and resistance genes that can interact with microbes in a new area. It is not just the classic pathogens that may be relevant to the emergence of a new disease but the individual traveler's total microbiologic "baggage."6. Visitors to a region may lack immunity to locally endemic infections, such as hepatitis A and sand-fly fever. Visitors may suffer severe or different manifestations of infection or disease at an age when the local population is immune to it. Resettlement of populations into malaria-endemic regions can lead to a high death rate from falciparum malaria.7. Kala-azar caused a deadly outbreak in remote villages in southern Sudan in 1994. The origin was thought to be the villagers' exposure to the sand-fly vector during migration to a food distribution center that had been established by a relief organization (24). The migration took a malnourished population from a nonendemic zone into the southern part of the kala-azar endemic zone. Unfamiliarity with the disease and the poor nutritional status of the population probably contributed to a high death rate (24).8. Behavioral patterns in a new region may place visitors at risk for infection, while the local population, possibly because of their knowledge of disease risks, may not be at risk. Behavior patterns may involve food preparation (such as eating some foods raw), clothing (or lack of it) (for example, going barefooted), sleeping arrangements (sleeping on the ground or out of doors in an unscreened area), and contact with animals.9. Susceptibility of a population may vary because of genetic differences. A microbe introduced into a new region may have a greater or lesser impact, depending on the host population. Genetic factors influence susceptibility to and expression of several infectious diseases. Although these interactions are not yet well defined for most infections, genetic factors influence infections caused by different classes of organisms, including cholera (25,26), parvovirus infection (27), malaria, and Helicobacter pylori infection (28).

To determine the consequences of travel both the traveler and the population visited must be considered. Migration may be in only one direction, though travel often involves returning to the point of origin, perhaps after the traveler has made many stops along the way. The changes in the various ecosystems as a consequence of the migration guide the emergence of diseases any study that simply focuses on the traveler is too narrow.

The distance traversed is less important than the differences in biological life in different areas and differences in receptivity and vulnerability. In thinking about disease emergence, what matters is the potential of a disease to appear in a place, population, or extent not previously reported.

What is the long-term impact of migration and travel on human disease? Carriage of pathogens is only part of the influence on disease emergence. Introduced technology, farming methods, treatment and drugs, chemicals, and pesticides may have a far greater and longer impact on disease patterns in a region than the life of a person. Deforestation, building of dams, and opening of roads into previously inaccessible areas have all been associated with population movements and changes in distribution and frequency of a variety of infections in humans (such as malaria, schistosomiasis, Rift Valley fever, and sexually transmitted diseases).

Increasingly the vehicle of transportation is the site or even the source of outbreaks. During travel, people from diverse origins are enclosed in close proximity for a hours or days and then discharged to move on to many distant places. These temporary new habitats, jumbo jets or huge ocean liners, can be the sites for dissemination of the microbes (as happens, for example with Legionella pneumophila infections (29), foodborne infections, and cholera) or provide a milieu for person-to-person transmission (influenza, tuberculosis (30,31).

Shipping and Commerce

The biomass of humans constitutes only a fraction of the matter moved about the earth. Humans carry and send a huge volume of plants, animals and other materials all over the face of the globe. Much of this movement results from the planned transport of goods from one place to another, but some is an unintended consequence of shipping and travel. All has an impact on the juxtaposition of various species in different ecosystems. "Hitchhikers" include all manner of biologic life, both microscopic and macroscopic. Animals can carry potential human pathogens and vectors. The globalization of markets brings fresh fruits and vegetables to dinner tables thousands of miles from where they were grown, fertilized, and picked. Tunnels, bridges, and ferries form means to traverse natural barriers to species spread. The roads built to transport people often speed the movement of diseases from one area to another. Mass processing and wide distribution networks allow for the amplification and wide dissemination of potential human microbes.

Examples of introduced species include plants and animals--insects, microbes, and marine organisms.1. Ships convey marine organisms on their hulls and in their ballast water. For example, 367 different species were identified in ballast water of ships traveling between Japan and Coos Bay, Oregon (32). Introductions have had devastating effects in some areas, for example such as the Black and Azov seas, where newly introduced jellyfish-like creatures called ctenophores have ruined local fishing (33).2. Vibrio cholerae may have been introduced to South America by shipping (34). Researchers isolated the organism in samples of ballast, bilge, and sewage from 3 of 14 cargo ships docked at Gulf of Mexico ports. The ships had last ports of call in Brazil, Colombia, and Chile (35). V. cholerae O1, serotype Inaba, biotype El Tor, indistinguishable from the Latin American epidemic strain, was found in oysters and oyster-eating fish from closed oyster beds in Mobile Bay, Alabama (36). V. cholerae O139 has spread along waterways in Asia, although the people carried on the boats doubtless played a role (37,38).3. Aedes albopictus was introduced into the United States inside used tires shipped from Asia (39,40). The mosquito's introduction causes concern because it is an aggressive biter, survives in both forest and suburban habitats, and appears to be a competent vector for several human pathogens. It has been associated with epidemic dengue fever transmission in Asia and is a competent laboratory vector of La Crosse, yellow fever, and other viruses (41). In Florida, 14 strains of eastern equine encephalitis virus have been isolated from A. albopictus (42). The mosquito is now established in at least 21 of the contiguous states in United States and in Hawaii.4. The African anopheles mosquitoes arrived in Brazil in about 1929. This vector could breed under conditions other New World mosquitoes could not. Although the malaria parasite was already found in Brazil, this new vector expanded the range of transmission. An estimated 20,000 persons died of malaria before the introduced anopheles mosquitoes were eliminated.5. It has been repeatedly demonstrated that mosquitoes are present--and--survive on international flights. In random searches of airplanes in London, mosquitoes were found on 12 of 67 airplanes from tropical countries (43). Arthropods can survive even more extreme environments. In one study, mosquitoes, house flies, and beetles placed in wheel bays of Boeing 747B aircraft survived flights of 6-9 hours with external temperatures of -42° C (43). Airplanes have also carried infective mosquitoes that caused human infection outside malaria-endemic areas (in Europe, for example).6. Vehicles can transport vectors over land. Glossina palpalis, a vector for African trypanosomiasis (sleeping sickness), can fly up to 21 km but can be transported much longer distances on animals and in land vehicles.7. Seven persons in Marburg, Germany, died after handling blood and tissues from African green monkeys from Uganda. The tissues contained an organism later named Marburg virus (44).8. Exotic animals transported from their usual habitats are clustered in zoos others are used in research laboratories where they have occasionally caused severe disease in humans. Two examples are B virus from primates (45) and hemorrhagic fever with renal syndrome from rodents (46).9. The world trade and globalization of organs, tissues, blood, and blood products is growing. Researchers are considering animals as sources for tissues and organs for transplantation (47).10. Plants may not directly cause human disease. But they can alter an ecosystem and facilitate the breeding of a vector for human disease. This can also displace traditional crops that provide essential nutrition. Vertical transmission of plant pathogens (and spread of plant diseases) can result from seed movement (48). Carriage of seeds into new areas can introduce plant pathogens.11.Migration and altered environments have increased the so-called weedy species. These species migrate easily and have high rates of reproduction. If they lack local predators, they can displace other species and often upset local ecology.

Introduction of Species into New Areas

Introducing species into new geographic areas is not new, but the current volume and frequency of introductions are unprecedented. A pathogen's survival and spread in a new environment are determined by its basic reproductive rate, which is the average number of successful offspring a parasite can produce (49). To invade and establish itself in a host population, a parasitic species must have a basic reproductive rate exceeding one (49). The simplicity of this statement belies the complexity of circumstances that influence invasion and persistence. These circumstances encompass biological, social, and environmental factors.

As noted already, factors that can influence receptivity include climate and environmental conditions, sanitation, socioeconomic conditions (50), behavior, nutrition, and genetics. V. cholerae persists in an aquatic reservoir off the Gulf Coast of the United States, yet epidemic cholera has not been a problem in the United States. Where poverty and poor sanitation prevail, the presence of V. cholerae can be a source of endemic disease and periodic epidemics.

Disease emergence is often complex. An outbreak of malaria in San Diego, California, occurred when parasitemic migrant workers were employed in an area where mosquitoes capable of transmitting malaria had access to the workers and to a susceptible human population (51). Many conditions had to be met to allow transmission.

Migration may introduce parasites into an area where a different intermediate host or vector could change the incidence of disease. Cycling through a different host can lead to different transmission rates, different infectivity, and even different clinical expression. A parasite may be more successful in a new site because of a larger susceptible population or the absence of predators.

Confluence of Events

Massive global travel is taking place simultaneously with many other processes that favor the emergence of disease. For example, the human population is more vulnerable because of aging, immunosuppression from medical treatment and disease (such as AIDS), the presence of prostheses (e.g., artificial heart valves and joints), exposure to chemicals and environmental pollutants that may act synergistically with microbes to increase the risk of diseases, increased poverty, crowding and stress, and increased exposure to UV radiation. Technologic changes, while providing many benefits, can also promote disease dissemination. Resistance of microbes and insects to antimicrobial drugs and pesticides interferes with the control of infections and allows transmission to continue. Changes in land use can alter the presence and abundance of vectors and intermediate hosts.

Microbes are enormously resilient and adaptable. They have short life spans, which allow rapid genetic change. Humans, by comparison, are slow to change genetically but can change their behavior. People move and construct barriers to prevent contact with microparasites, macroparasites, and the extremes of the environment. Technology fosters a perception of human invincibility but actually creates new vulnerabilities, as it enables us to go deeper, higher, and into more remote and hostile environments. Studies show that no place on earth is devoid of microbes. Their range and resiliency are truly phenomenal. Only a fraction of the existing microbes have been characterized. Travel and exploration provide a greater opportunity for humans to come into unsampled regions with these uncharacterized microbes.

Summary and Conclusions

Global travel and the evolution of microbes will continue. New infections will continue to emerge, and known infections will change in distribution, severity and frequency. Travel will continue to be a potent factor in disease emergence. The current world circumstances juxtapose people, parasites, plants, animals, and chemicals in a way that precludes timely adaptation. The combination of movement at many levels and profound change in the physical environment can lead to unanticipated diseases spread by multiple channels. In many instances, the use of containment or quarantine is not feasible. Research and surveillance can map the global movement and evolution of microbes and guide interventions. Integration of knowledge and skills from many disciplines--the social, biological, and physical sciences--is needed. The focus should be system analysis and the ecosystem rather than a disease, microbe, or host.

Dr. Wilson is Chief of Infectious Diseases at Mount Auburn Hospital in Cambridge and Assistant Professor of Population and International Health and Epidemiology at the Harvard School of Public Health. An active participant in the Harvard Working Group on New and Reemergent Infectious Diseases since its inception in 1991, she is the senior editor, with Richard Levins and Andrew Spielman, of Disease in Evolution: Global Changes and Emergence of Infectious Diseases (3), a book based on the 1993 Woods Hole workshop on emerging infections.


Google's Pixel 5 is a new kind of flagship that puts software and imaging first. That's not to say the rest of the hardware experience is an afterthought&mdashand with wireless charging and an IP68 rating, we think it's worth the additional $100&ndash200 over the Pixel 4a 5G. Compared with the Galaxy S20 FE 45G, however, the choice isn't as clear. The Pixel offers a superior software experience and better low-light imaging, but the Galaxy has a higher refresh rate and a much more powerful processor. It's a close call, and while the Galaxy gets our nod as Editors' Choice, the Pixel 5 is a fine alternative, as well as the type of flagship phone we hope to see more of in the future.

The Celtic Review

The Celtic Review was an early twentieth-century periodical focusing on Celtic and Gaelic literature and scholarship. Some articles are written in Irish and Welsh.

Publication History

The Celtic Review was published in 10 volumes from 1904-1916.

Persistent Archives of Complete Issues

  • 1904-1916: HathiTrust has volumes 1-10 online. Access is restricted outside the UNited States.
  • 1904: The Internet Archive has volume 1, number 1 online.
  • 1905-1906: The Internet Archive has volume 2 online.
  • 1906-1907: The Internet Archive has volume 3 online.
  • 1907-1908: The Internet Archive has volume 4 online.
  • 1908-1909: The Internet archive has volume 5 online.
  • 1909-1910: has volume 6 online.
  • 1911: The Internet Archive has volume 7, number 26 online.
  • 1911: The Internet Archive has volume 7, number 27 online.
  • 1912-1913: The Internet Archive has volume 8 online.
  • 1913-1914: The Internet Archive has volume 9 online.
  • 1914-1916: The Internet Archive has volume 10 online.

This is a record of a major serial archive. This page is maintained for The Online Books Page. (See our criteria for listing serial archives.) This page has no affiliation with the serial or its publisher.

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