Bark for the bite

Mark Honigsbaum follows the explorers who went in search of the antimalarial drug quinine in The Fever Trail

The Fever Trail
Mark Honigsbaum
Macmillan £18.99, pp333

Beware and take care of the Bight of Benin
There's one that comes out for forty goes in.

Thus begins a nineteenth-century sailor's refrain, inspired by the deaths of thousands of servicemen from a disease that has blighted Britain throughout history: malaria. It helped kill Cromwell, destroyed most of our forces during the War of Jenkins's Ear (1739-1741), and by the Victorian Age was wrecking our colonial aspirations in Africa and India.

Unprotected, British soldiers and settlers were slaughtered by plasmodium parasites passed into their blood by infected mosquitoes. The only salvation, it was realised, was quinine, isolated from the bark of the cinchona tree that grows in the Andes' most inaccessible ranges. But getting the drug into our servicemen's systems proved to be a decidedly tricky business, as former Observer reporter Mark Honigsbaum makes clear in this neatly written, authoritative story of the hunt for a malaria cure.

For a start, there are dozens of species of cinchona, but only one has a bark rich in quinine, a fact that early naturalists were slow to appreciate. It took expeditions by dozens of Spanish, French and British quinine hunters, who headed up the Orinoco, crawled over the Apolobamba and splashed across the Casiquiare to reveal the truth. Along the way, most of these explorers succumbed to the very disease for which they were seeking a cure, while the few survivors still suffered grim misfortune.

French explorer La Condamine actually got the right cinchona seeds and plants on a boat to Europe, but lost them when a wave swept them away, while his compatriot de Jussieu warned his Indian servant so severely about guarding sample boxes that the man assumed they must be stuffed with gold and stole them. 'It was as if the tree was protected by some ancient Indian curse,' the author notes.

In the end, the cinchona gave up its secrets - and within decades was reduced to near extinction as widespread felling and stripping of forests ensued. 'By the 1850s cinchona forests were slowly but surely being raped to exhaustion,' says Honigsbaum.

Finally, the British and Dutch managed to smuggle cinchonas to their Asian colonies and began producing their own anti-malarial drugs for their settlers. Both nations excused this act of grand biological theft as philanthropy. Without us, Earth would have no quinine left, they claimed, with some truth.

It's a fascinating story, though quinine has certainly not proved to be the world's salvation, for malaria still kills millions every year. We need preventative vaccines, not post-infection drugs, as Honigsbaum notes, a very different, but equally fascinating story.