The news that Richard III suffered from roundworm reminds us how grateful we should be for the advances of modern sanitation and medicine. In both Richard's era and long after, rich and poor were horribly vulnerable to diseases that either killed you efficiently or made you wish you were dead.

1. Sweating sickness

If Richard had not died at Bosworth field in 1485, he might well have been struck down by this malady. First recorded in Shrewsbury in mid-April 1485, this terrifying new disease had reached London by 7 July. The sweating sickness resembled the more recent Ebola virus in its terrifying speed. It was to return to Britain in 1508, 1517, 1528, and 1551, and in 1552, the physician John Caius wrote of how it "immediately killed some in opening their windows, some in playing with children in their street doors, some in one hour, many in two it destroyed, and at the longest, to them that merrily dined, it gave a sorrowful supper".

2. The plague

At its outset, the bubonic plague of 1348 had killed around 40% of the English population. It was to recur over the following centuries; Shakespeare was born in a plague year. With one in 15 of his parish infected as he lay in his cradle in September 1564, the infant genius may well have been indebted to an especially murderous cat, efficiently snapping the necks of infected rats before they could approach the swaddled bard. In his maturity, Shakespeare was lucky to suffer no more than closed theatres during the severe London plagues of 1592-3, 1603, and 1609. And in 1625, two years after the First Folio, the plague snatched away around 35,000 Londoners – perhaps as much as one fifth of the capital's population.

3. Smallpox

Another thing which both Shakespeare and Elizabeth I survived. Elizabeth was scarred after contracting the disease in 1562, while in September 1660 smallpox claimed the life of Charles II's youngest brother, Henry, and his sister Mary. Until Edward Jenner introduced vaccination in 1798, medicine remained largely powerless against this durable scourge. By the 1760s, the devastating power of smallpox in America was so well-recognised that the British commander-in-chief, Sir Jeffrey Amherst, discussed, and most likely deliberately gave, infected blankets to rebellious Native American communities as a tactic of early germ warfare.

4. Worms

As for the roundworms? Recent commentators were right to emphasise that Richard III got off lightly by comparison with other victims of this parasite. For hundreds of years the poor struggled to get meals in their stomachs, only to have worms of horrifying size and variety eat these for them before they were digested. In 1668, the physician William Ramsey lamented the "several species of worms macerating and direfully cruciating every part of the bodies of mankind", asserting that they had indeed killed "more than either sword or plague". Ramsey recalled a sufferer from Montpellier who voided a flatworm 7ft long.

Innumerable other victims expelled these creatures through their mouths, anuses or ears, as well as in urine. Piero Camporesi tells of "a five-year-old child in whom worms had gnawed through the belly and come out of the navel", while one 40-year-old man had a swelling in his groin which finally split to release three huge worms.

5. Phthiriasis

Richard III might also have taken comfort from the fact that – so far as we know – he escaped the now forgotten parasite infection called phthiriasis. For this condition, which was both disgusting and often fatal, certainly did not spare the privileged. In 1556, "Portuguese physician Amatus Lusitanus described the death of the nobleman Tabora, who had many swellings all over his body, from which small insects streamed out incessantly; two of his Ethiopian slaves were employed in emptying small baskets of them into the sea". In just a few weeks Tabora died, devoured alive "by these 'lice' engendered under his own skin".

Although these "lice" were apparently mites, they did indeed eat their victims alive. As Jan Bondeson explains, the biological economy of phthiriasis was horribly simple: the host's flesh was steadily transformed into ever more devouring insects. Another aristocratic victim was the Elizabethan noblewoman, Lady Penruddock, who "developed hundreds of small insect-filled boils and perished in phthiriasis".

Much later, in 1808, a Prussian military surgeon examined "a 13-year-old boy with a large head tumour". Eight days on, the boy "seemed to be dying, and the tumour was enormous". On cutting it open, the surgeon saw "a mass of solidly packed insects, but not a droplet of pus or moisture. After the insects had been scraped out" the boy was treated with ointment and the cavity "injected with mercury", and he presently made a complete recovery. Given that phthiriasis was also used as a slander against one's powerful enemies, a king such as Richard was lucky that he neither caught it, nor had it bestowed on him by rumour. Still worried about Fresher's flu?