IELTS Academic Reading Practice Test 367

Rochester, Minnesota, was in the 1880s a small town on the northern plains of the United States, reached by railway and serving the farms around it. Its best-known doctor, William Worrall Mayo, had been born in Salford, near Manchester, in 1819, and had crossed the Atlantic as a young man. After some years working in a pharmacy he qualified in medicine, and during the Civil War he served as an examining surgeon for the Union army, assessing recruits before they were sent to fight. In 1864 he settled in Rochester, where he combined general practice with a range of civic activities.

In August 1883 a tornado struck the town and destroyed a large part of it. Among the buildings damaged were the convent and school of a small community of Franciscan sisters who had settled in Rochester a few years earlier to teach the children of settlers. Mayo took charge of the medical response, setting up a temporary hospital and organising the care of the injured. The sisters helped to nurse the casualties, and their leader, Mother Alfred Moes, was struck by the doctor's energy and by the orderly way in which he and his colleagues worked together.

When the emergency had passed, Mother Moes came to Mayo with a proposal. The community, she suggested, should build and staff a hospital in the town, and the doctors should treat the patients in it. Mayo was doubtful: he was already in his sixties, the town was small, and he doubted that a hospital could be sustained there. The sisters persisted, travelling through the surrounding region to collect donations from farmers and merchants. In 1889 St Mary's Hospital opened, with Mayo as its medical director and the nuns as its nursing staff.

It was an unusual alliance, bringing together a nursing order and a group of doctors in an institution that was neither a charitable almshouse for the destitute nor a private venture run for profit. Mayo's two sons, William James and Charles Horace, had by then trained in medicine, first in the United States and then in Europe, and they returned to join their father. The three worked as a partnership, and the sons brought back techniques in surgery and in the use of anaesthesia that few American doctors had encountered. As patients began to travel to Rochester from neighbouring states, other doctors were drawn to the town.

The practice grew into something that had no real equivalent at the time: a group of specialists working under one roof, sharing patients, records and equipment. Among those who joined were Augustus Stinchfield, an experienced physician, Christopher Graham, a physician, E. Starr Judd, a surgeon, and Henry Plummer, who combined clinical work with a talent for design and engineering.

The partners agreed on two principles that were then radical. Every doctor would be paid a fixed salary rather than a fee for each service, so that nobody had an incentive to order unnecessary treatment; and patients would be seen by as many specialists as their condition required, with the cost shared rather than charged separately by each.

Nurses at St Mary's came to specialise in giving ether, a task that most hospitals left to whichever doctor was free, and their skill contributed to the clinic's surgical results. Plummer's most lasting contribution, however, was to the medical record. Before his reforms, each department kept its own notes, so a patient's history was scattered across several files. Plummer gave every patient a single number and insisted that all notes, laboratory results and X-rays be kept together under it. The clinic adopted X-rays within a few years of their discovery in 1895, and the unified record allowed thousands of cases to be compared and patients to be followed over many years.

By the early twentieth century the practice had outgrown its premises. A new clinic building, designed with Plummer's help and opened in 1914, was among the first to be planned around the movement of patients and records rather than around the convenience of the doctors. In 1919 the brothers transferred their property into a charitable association, so that the clinic's income would support medical education and research rather than enrich its owners. The Mayo Foundation had been established in 1915 to fund graduate training and investigation.

By the 1920s the clinic had become one of the largest medical practices in the world. Patients arrived by train from across the country, and newspapers described the town as a place of pilgrimage. Its reputation rested on results that could be counted: it published figures showing the proportion of patients who died after particular operations, at a time when such statistics were rarely made public. W. W. Mayo did not live to see the clinic's full expansion: he died in 1911 at the age of 91. Both of his sons died in 1939, within a few months of each other.

A medical school followed in 1972, and the clinic expanded into a large institution with sites in several states. Yet the principles that the founders set out in Rochester — salaried doctors, shared records, treatment by a team rather than by a single practitioner — have become so ordinary that it is easy to forget how contested they once were. When W. W. Mayo arrived in a small Minnesota town in 1864, nobody would have predicted that his household practice would become a model for the organisation of medicine around the world.

A respirator mask does not work like a sieve. A sieve stops anything larger than its holes, so a simple calculation might suggest that a fabric with gaps a few tens of micrometres wide would be useless against a virus less than a tenth of a micrometre across. In reality the air a wearer breathes passes through a dense, tangled web of fibres, and particles are removed not because they are too big to fit through the gaps but because they collide with the fibres. The gaps are far wider than the particles, yet the route through the web is long and winding.

A disposable respirator built to meet a filtration standard usually has three layers. The outer layer, made of a stronger, spunbond fabric, holds the shape of the mask and resists splashes. The inner layer, softer and designed to sit against the skin, absorbs moisture from the breath. Between them lies the filter itself, a much thinner sheet that does the actual work. All three are non-woven materials: the fibres are laid down and bonded together rather than woven, which allows them to be made extremely fine and densely packed.

The filtering layer is made by a process called melt-blowing. Polypropylene, a common plastic, is melted and forced through a row of tiny nozzles, and as it emerges it is blasted by hot air that stretches it into fibres only a few micrometres thick. These fibres are blown onto a moving belt, where they cool and form a random mat. The mat has a very large surface area for its weight, so that even a thin sheet contains an enormous number of obstacles.

Two mechanical processes account for much of the filtration. The first is interception: a particle small enough to follow the airflow around a fibre may still touch it if it passes very close, and once it touches, it sticks. The second is inertial impaction. Larger particles, being heavier, cannot turn as sharply as the air when it curves around a fibre; they continue in a straighter line and hit the fibre head-on. Impaction therefore works best for the biggest particles.

The third mechanical process is diffusion, and it matters most for the smallest particles. These are so light that they are constantly buffeted by collisions with gas molecules, and their path through the filter becomes a random zigzag rather than a smooth line. The longer they spend inside the filter, the more likely they are to strike a fibre. Because large particles are caught by impaction and small ones by diffusion, there is a size in between at which both effects are weak. For the filters used in respirators this most penetrating size is roughly 0.3 micrometres, and it is the size at which standards test performance.

The fourth mechanism is not mechanical at all. The fibres in the filtering layer are made of a plastic that holds an electric charge, a material known as an electret, and the field around each fibre attracts particles even when they carry no charge of their own. A neutral particle becomes polarised as it approaches and is pulled towards the fibre. This electrostatic attraction adds to the efficiency of the filter without adding to the effort of breathing. It is also easily destroyed: washing a mask, or soaking it in alcohol, can remove the charge.

All of this describes what happens to air that passes through the filter, and much of the air breathed through a mask may not do so at all. If the edges do not sit tightly against the face, air takes the easier route around the filter, carrying its particles with it. Manufacturers therefore add features designed to close the gaps. A thin metal strip, the nose clip, runs across the top edge and is bent to fit the bridge of the nose. Inside that edge, a strip of soft foam cushions the pressure against the skin. Two elastic straps at the sides pass behind the head and hold the edges in place, though leakage around them remains common.

Certification attempts to take account of this. A respirator marked N95 in the United States, FFP2 in Europe or P2 in Australia and New Zealand must remove at least 94 or 95 per cent, depending on the standard, of particles of the most penetrating size, and each standard also sets a limit on how hard the mask may be to breathe through. The tests are performed on the material, however, and a mask that passes them can still perform badly on a face it does not fit. That is why health services that issue respirators to staff also test the seal on each individual.

A surgical mask is made in a similar way and contains a similar melt-blown layer, but it is cut loosely and does not seal against the face. Its main purpose is to reduce the number of droplets a wearer releases, not to protect the wearer from what others release. Some respirators carry a valve in the centre front, a one-way flap that opens when the wearer breathes out; it makes exhalation easier but lets unfiltered breath into the surrounding air.

How much protection masks give in ordinary use remains contested. Laboratory measurements are precise but artificial, and studies of masks in hospitals and communities during the COVID-19 pandemic produced mixed results: some found that well-fitted respirators protected health workers better than surgical masks, while others found little difference. Comfort matters as much as filtration, since a mask that is hot or hard to breathe through is soon pulled down or taken off. Researchers therefore measure not only what a material stops but how long people are willing to wear it.

Every winter, as influenza returns and buses and trains fill with coughing passengers, somebody proposes that masks should be compulsory on public transport during the flu season. The proposal is easy to state and surprisingly hard to answer. It sits at the point where evidence about the physical world meets questions about how a society should treat its members, and the two are usually argued as though they were the same thing. I want to separate them, because the case for compulsion is weaker than its supporters believe, and the case for doing nothing at all is weaker still.

The argument in favour begins with something uncontroversial. Influenza spreads through the air, in droplets and in the finer particles that remain suspended when a crowded carriage is warm and poorly ventilated. A well-fitting mask worn by an infected person reduces the number of those particles that reach the air, and masks worn by everyone reduce the number each passenger breathes in. On a busy commuter train in January, where hundreds of people sit close together for half an hour or more, that reduction should matter. Compulsion, on this view, simply ensures that enough people take a step that is cheap, temporary and easily reversed.

There is force in this. Advice alone reaches only the conscientious, and the people most likely to be infectious are often those with no choice but to travel: the worker on a zero-hours contract, the parent collecting a child from school, the passenger who cannot afford a taxi. A rule that applies to everyone is, in one respect, more equal than a recommendation that only the careful follow. Nor is the burden absurd, since a cloth or surgical mask costs little and a season lasts a few months.

Yet the gap between what a mask can do in a laboratory and what a requirement achieves in a city is enormous. The filtration figures quoted in support of mandates describe air that has passed through the material; they say nothing about how many passengers wear a mask over the nose, keep it on for the whole journey and replace it when it becomes damp. In practice, compliance in the settings where transmission is most likely tends to be the lowest, and a legal duty does not so much change the behaviour of a tired commuter as give officials a reason to scold them.

Enforcement is the difficulty that supporters pass over most quickly. Somebody must decide who is exempt and who is not, and somebody must challenge the man at the barrier who says he cannot breathe in a mask. In practice the task falls to drivers, conductors and station staff, who are neither trained nor paid for it. The penalty, when it is applied, is likely to fall on those least able to argue: people with language difficulties, people with mental health problems, people already in conflict with the authorities. A measure intended to protect the vulnerable can end up punishing them.

The strongest evidence offered for masks comes from the winter of 2020-21, when influenza all but disappeared across much of the world. That season, however, was unlike any other in modern history. Schools and offices were closed, travel was restricted, hands were washed obsessively and masks were worn everywhere, not merely on public transport. It is impossible to attribute the disappearance of flu to any single one of these measures, and the attempt to do so is a good example of the temptation to credit the most visible intervention with the whole of the result.

A mandate also carries a cost that is rarely counted. It converts a small act of consideration into a test of obedience. It also invites the belief that once the rule is obeyed nothing else need be done. Yet the measures that would make a real difference to winter infection are unglamorous and largely structural: better ventilation on trains and buses, which is a matter of design and money; arrangements that allow people to stay at home when they are ill, which requires sick pay; and clean air in the places where people wait. These are harder to photograph than a mask.

None of this means that masks are useless, or that a government should say nothing. The sensible course is to make good masks free and easy to find at stations, to explain when they help, and to encourage them in the situations where the benefit is clearest: crowded peak services, and the weeks when influenza is circulating widely. Compulsion should be held in reserve for places where the evidence is stronger and the population is more or less captive, such as hospitals and care homes, where staff and visitors already accept such conditions.

So my answer to the question is a qualified no. In flu season a mask is a reasonable thing for a passenger to put on, and a state that encouraged the habit would do some good. But a legal requirement on public transport asks the law to accomplish something that the law does poorly, and it distracts attention from the duller measures that would keep more people well. I would rather see the money spent on ventilation and sick pay.