This week marked a signal achievement. A group from Oxford University announced the first acceptable vaccine ever against malaria. One might be forgiven for wondering why it has taken so long when the covid-19 vaccines have taken just over a year ... even whether it is a kind of economic apartheid given that malaria victims reside in the poorest countries of the world.
It turns out that the difficulties of making a malaria vaccine have been due to the complexity of the pathogen itself. The malarial parasite has thousands of genes; by way of comparison, the coronavirus has about a dozen. It means malaria requires a very high immune response to fight it off.
A trial of the vaccine in Burkina Faso has yielded an efficacy of 77 percent for subjects given a high dose and 71 percent for the low-dose recipients. The World Health Organization (WHO) had specified a goal of 75 percent for effective deployment in the population. A previous vaccine demonstrated only 55 percent effectiveness. The seriousness of the disease can be ascertained from the statistics. In 2019, 229 million new malaria infections were recorded and 409-thousand people died. Moreover, many who recover can be severely debilitated by recurring bouts of the disease.
Vaccination has an interesting history. The story begins with Edward Jenner. A country doctor with a keen and questioning mind, he had observed smallpox as a deadly and ravaging disease. He also noticed that milkmaids never seemed to get it. However, they had all had cowpox, a mild variant, which at some time or another they would have caught from the cows they milked.
It was 1796 and Jenner desperate for a smallpox cure followed up his theory, of which he was now quite certain, with an experiment. On May14, 1796, Jenner inoculated James Phipps, the eight-year-old son of Jenner's gardener. He used scraped pus from cowpox blisters on the hands of Sarah Nelmes, a milkmaid who had caught cowpox from a cow named Blossom. Blossom's hide now hangs in the library of St. George's Hospital, Jenner's alma mater.
Phipps was inoculated on both arms with the cowpox material. The result was a mild fever but nothing serious. Next he inoculated Phipps with variolous material, a weakened form of smallpox bacteria often dried from powdered scabs. No disease followed, even on repetition. He followed this experiment with 23 additional subjects (for a round two dozen) with the same result. They were all immune to smallpox. Then he wrote about it.
Not new to science, Edward Jenner had earlier published a careful study of the cuckoo and its habit of laying its eggs in others' nests. He observed how the newly hatched cuckoo pushed hatchlings and other eggs out of the nest. The study was published resulting in his election as a Fellow of the Royal Society. He was therefore well-suited to spread the word about immunization against smallpox through vaccination with cowpox.
Truth be told, inoculation was not new. People who had traveled to Constantinople reported on its use by Ottoman physicians. And around Jenner's time, there was a certain Johnny Notions, a self-taught healer, who used it in the Shetland Isles then being devastated by a smallpox epidemic. Others had even used cowpox earlier. But Jenner was able to rationally formalize and explain the procedure and to continue his efforts even though The Royal Society did not accept his initial paper. Persistence pays and finally even Napoleon, with whom Britain was at war, awarded him a medal and had his own troops vaccinated.
