IELTS Academic Reading Practice Test 347

In the summer of 1906 a wealthy New York family, the Warrens, rented a house at Oyster Bay on Long Island for their holiday. Within weeks six of the eleven people staying there fell ill with typhoid fever, a bacterial infection that was then a serious threat in American cities and killed perhaps one sufferer in ten. The outbreak was puzzling, because the house stood in open countryside with a clean water supply and no obvious source of contamination. The owner of the house, anxious about the property's reputation, engaged a sanitary engineer named George Soper, who had already investigated several similar outbreaks, to find the cause.

Soper began by questioning the household. He knew that typhoid bacteria usually enter the body through the mouth, in food or water that has been contaminated by the waste of an infected person. No one in the family had been ill, but a cook had left the Warrens' employment shortly before the outbreak began. By tracing the woman's previous employers, Soper discovered that she had worked for eight families since 1900 and that typhoid had broken out in seven of their households. The cook was Mary Mallon, an Irish-born woman of about thirty-seven who had emigrated from County Tyrone as a teenager and had built a reputation as one of the best cooks in the city.

In March 1907 Soper called at a house on Park Avenue where Mallon was then working and explained his theory. She refused to accept it, and when he asked for samples of blood, urine and faeces she is reported to have seized a carving fork and driven him from the kitchen. Soper then approached the New York City health department, whose officials took the view that a woman spreading a fatal disease could not be allowed to continue cooking. A few days later an ambulance and several police officers arrived at the house, and Mallon was taken, protesting, to a hospital on North Brother Island in the East River. Tests on her faeces revealed large numbers of typhoid bacteria.

Mallon's case shocked the public because it contradicted what people thought they knew about infectious disease. A carrier, as bacteriologists had recently begun to understand, is a person who harbours a pathogen without suffering from it. In typhoid, the bacteria can persist for years in the gallbladder, multiplying in the bile and passing continuously into the intestine, from which they are shed in the faeces. A carrier who prepares food without washing her hands thoroughly can therefore infect a whole household while remaining perfectly well. German researchers had described such chronic carriers only a few years earlier, and many doctors still doubted that a healthy person could be so dangerous.

Mallon never accepted the diagnosis. She had never, so far as anyone could establish, suffered a serious attack of typhoid, and she pointed out that many people in the kitchens where she worked had remained healthy. She spent almost three years on North Brother Island, mostly in a small cottage separated from the hospital's other patients, and repeatedly demanded her freedom. In 1910 a new health commissioner, persuaded that she had been treated harshly, released her on condition that she never again worked as a cook and reported regularly to the authorities.

For five years nothing more was heard of her. Then, in 1915, a serious outbreak struck the Sloane Hospital for Women in Manhattan, where a cook had recently been hired under a different name. Twenty-five patients and staff developed typhoid and two of them died. When the hospital's laboratory tested the cook, her faeces were found to contain the same bacteria, and Mallon admitted who she was. She was sent back to North Brother Island, this time with no promise of release.

By then she had become a national figure, though not a sympathetic one. The nickname by which she is remembered appeared in print within a few years of her first detention, and it carried an accusation that she resented for the rest of her life. Newspapers portrayed her as a reckless immigrant who had knowingly poisoned the families she served, a story far simpler than the truth: she had never been taught how infection spread, she refused to believe the evidence, and she had no other way of earning a living.

On the island she was given work in the hospital laboratory, washing bottles and performing other small tasks, and she became a familiar figure to the staff. A stroke in the early 1930s left her partly paralysed, and she spent her last years in the island's infirmary. She died there in November 1938, after more than twenty-three years in isolation. Only a handful of people attended her funeral.

Mallon's case changed public health practice. Health departments began to search for carriers after outbreaks, to test people who handled food and to keep registers of those known to be infectious, and the investigation of individual cases became a routine part of epidemiology. It also exposed a question that has never been fully resolved. Mallon had committed no crime, yet she lost her liberty for decades, and the officials who detained her acted on evidence that would now be considered thin. Most countries have laws permitting the compulsory isolation of people who pose a risk to others, but the balance between individual freedom and the safety of the community remains as difficult as it was in 1907.

Most people know that blood travels around the body in a closed system of vessels, driven by the heart. Far fewer are aware of a second network that runs alongside it. The lymphatic system consists of a branching web of thin-walled vessels, several hundred small bean-shaped nodes, and a handful of organs, among them the spleen and the thymus. It has two jobs. It collects fluid that leaks out of blood vessels and returns it to the bloodstream, and it provides the places where white blood cells gather, recognise invaders and mount a response. Because it has no pump of its own, it depends on the movements of the body to keep its contents flowing.

Every day, the pressure of blood in the smallest vessels forces water and dissolved substances out through their walls into the surrounding tissue, delivering oxygen and nutrients to cells. Most of this fluid is drawn back into the vessels at their venous end, but not all of it. Two or three litres each day remain in the tissues, together with proteins that have escaped and waste products produced by cells. If it stayed there, the tissues would swell and the volume of blood would steadily fall. The lymphatic vessels are the route by which this surplus is carried away.

The smallest of these vessels, the lymphatic capillaries, are blind-ended: they begin in the tissue and go nowhere, unlike blood capillaries, which form continuous loops. Their walls are made of overlapping endothelial cells that behave like one-way flaps, opening when pressure in the surrounding tissue rises and closing when it falls, so that fluid and particles drift in but cannot leave. Fine filaments anchor the cells to the surrounding tissue and pull the flaps apart as it swells. These capillaries are also found in the lining of the small intestine, where they are known as lacteals. Digested fats are too large to enter blood capillaries, and the lacteals absorb them instead, carrying them into the lymph as a milky fluid called chyle.

From the capillaries, lymph passes into wider collecting vessels whose walls contain smooth muscle and numerous valves. These valves prevent any backflow, so that the fluid can only move towards the chest. Movement is produced partly by the vessels themselves, which contract rhythmically several times a minute, and partly by events in the body around them: the pressure of contracting muscles during exercise, the pulsing of nearby arteries and the changes in pressure produced by breathing. Eventually the lymph reaches two large ducts, the thoracic duct and the right lymphatic duct, which empty into veins at the base of the neck.

Along the route, lymph passes through lymph nodes, which act as filters and as meeting places for immune cells. Each node is enclosed in a fibrous capsule. Beneath it lies the cortex, an outer region densely packed with lymphocytes, and it is here that germinal centres form when a response is under way. The deeper part of the node, the medulla, contains large numbers of scavenging cells. These macrophages engulf bacteria, debris and dead cells that have been carried in with the lymph. Lymph enters through several afferent vessels that pierce the curved surface of the capsule and leaves through a single efferent vessel at a notch on the other side, known as the hilum.

A node that is fighting an infection becomes tender and enlarged, which is why doctors feel the neck and armpits when they suspect illness. Lymphocytes, the white cells that carry the ability to recognise particular molecules, circulate constantly between the blood and the nodes. When one of them meets a fragment of a pathogen displayed on the surface of a dendritic cell, it multiplies rapidly, producing a clone of cells with the same specificity. Some of these become effector cells that attack the infection; others persist as memory cells, ready to respond faster if the same organism returns.

Not all the work is done in the nodes. The thymus, a gland behind the breastbone, is where T lymphocytes mature; it is large in childhood and shrinks steadily from adolescence onwards. The spleen filters blood rather than lymph, removing worn-out red cells and responding to organisms that have reached the bloodstream. Tonsils and other patches of lymphoid tissue in the walls of the throat and gut guard the places where microbes most often enter. Together these organs contain a substantial share of the body's lymphocytes.

For most of the twentieth century, the brain was thought to have no lymphatic vessels at all. That assumption was overturned in 2015, when researchers studying mice described vessels of this kind running in the membranes that surround the brain. They were later reported in people as well. The vessels appear to drain fluid and waste from nervous tissue into the lymph nodes of the neck, and their discovery has raised the question of whether their failure contributes to conditions in which waste proteins accumulate in the brain. The answer is not yet known.

When lymph cannot drain properly, the result is lymphoedema, a persistent swelling of a limb. It most often follows surgery or radiotherapy for cancer, when lymph nodes and vessels are removed or damaged. There is no cure, but careful skin care, compression and specialised massage can control it. Cancer cells also use the network: they can enter lymphatic vessels and settle in the first node they reach, which is why surgeons often remove nearby nodes to check whether a tumour has begun to spread.

On most hospital wards a notice still fixes the hours during which patients may receive visitors, often to a couple of hours in the afternoon and a similar stretch in the evening. Such rules are so familiar that they are rarely questioned. Yet in recent years a number of hospitals in Britain and elsewhere have abandoned fixed hours altogether and invited families to come when they wish, including at mealtimes and late in the evening. The change has been welcomed by many patients and resented by some staff, and it raises a question about how hospitals see themselves.

Fixed visiting hours are a product of the late nineteenth century, when hospitals were run on military lines. Matrons controlled the wards, patients were expected to rest in silence, and relatives were treated as a disturbance rather than a support. Infection was poorly understood, and the fear of carrying disease onto a ward was genuine. Some of the rules also reflected a wish to keep a professional space in which nurses could work without being watched. The two-hour slot that many people still associate with hospital life is thus a historical accident rather than the result of any careful study.

The arguments for keeping visitors to defined times are not trivial. Sleep is disturbed on most wards, and patients recovering from surgery or illness need long stretches of quiet; a stream of relatives around the bed does nothing to help. Space is another constraint. A bay of four or six beds separated only by curtains cannot accommodate several visitors at each bedside without becoming crowded and noisy, and patients who have no visitors may find other people's families hard to endure. Restricting visiting during outbreaks of norovirus or influenza is an established measure, and no hospital can ignore it.

Staff have practical concerns too. Visitors arrive with questions, and a nurse who is interrupted while preparing drugs or changing a dressing may be distracted at exactly the wrong moment. Teaching and handover take place at the bedside, and a crowd of relatives makes them harder. Some doctors add that relatives can dominate a consultation, answering for a patient who would otherwise speak. These are real difficulties, and any policy that pretends otherwise will not survive contact with a busy ward at eight in the morning.

Against them stands a growing body of evidence and an even stronger body of experience. For patients with dementia, a familiar face is not a luxury but a form of treatment: it reduces agitation, helps with eating and drinking and prevents the confusion that unfamiliar surroundings produce. It was exactly this that prompted John's Campaign, begun in Britain in 2014 after the writer Nicci Gerrard described the effect of rigid rules on her father, who was in hospital with dementia. The campaign argues that a relative who provides essential care should not be treated as a visitor at all, and it has persuaded many hospitals to allow such carers to stay at any hour.

Research on the subject is thinner than campaigners sometimes suggest. Studies in intensive care, where visiting has traditionally been most restricted, have generally found that more flexible arrangements do not increase infection rates and are associated with greater satisfaction among relatives; some report less anxiety and confusion among patients. But such studies are few, they are rarely randomised, and they are difficult to separate from other changes in care. No one has shown in a controlled trial that open visiting shortens stays or saves lives.

There is also an uncomfortable point about fairness that both sides tend to avoid. Unrestricted visiting advantages patients whose families live nearby, have cars, or can take time off work. It may leave the patient in the next bed, whose daughter is in another country and whose friends are frail, more conscious of being alone. A policy designed to make hospitals more humane could therefore make the ward a more painful place for those without anyone to come. Any honest argument for open doors has to answer this.

The way out of the difficulty, it seems to me, is to stop treating visiting as a single activity. There is a difference between a social call, which is valuable but can usually be arranged, and the presence of a named carer who knows the patient's history, helps them eat, and notices when something is wrong. The first should be generous; the second should be treated as part of care. Hospitals that have made this distinction report that staff, initially resistant, come to value the information that families provide.

What, then, should a hospital do? My own view is that the fixed two-hour slot should go, to be replaced by a presumption of access that can be adjusted for the individual patient. Wards need the right to protect a rest period in the afternoon, to ask visitors to leave during an emergency, and to restrict access during an outbreak. They also need to ask each patient what they want, since some would rather be left in peace. But the starting point should be that a patient's family is an ally rather than an interruption, and that a rule which keeps a frightened ninety-year-old away from her husband for twenty-two hours a day cannot be justified by the convenience of the staff who enforce it.