Hugh Pennington

The announcement on 26 October that the Wellcome Trust, the Gates Foundation and the UK, US and Brazilian governments will spend $21.7 million over the next two years releasing Aedes aegypti mosquitoes infected with Wolbachia in Rio de Janeiro and Medellín is excellent news. Wolbachia, a bacterium that lives in the reproductive systems of insects and worms, is one of the commonest parasites in the world. In some of its invertebrate hosts it either kills males or feminises them. For others, infection with it is essential for fertility. Discovered in 1923 in the ovaries and testes of mosquitoes from Boston and Minneapolis, it remained an entomological curiosity for half a century before its importance began to be realised. Now it has its own website, and the Anti-Wolbachia Consortium, A-WOL, is funded by the Gates Foundation.

When a war goes wrong, a longstanding British political habit is to establish an official inquiry. They take many forms. Florence Nightingale used the Royal Commission on the Health of the Army (1858-62) to promulgate her views after Crimea. The Second Boer War engendered nearly as many fat volumes as Chilcot. Several covered ‘The Military Preparations … the supply of Men, Ammunition, Equipment and Transport … and Military Operations’, others ‘The Care and Treatment of the Sick and Wounded’. The Elgin Commission took evidence from the military commanders, and the secretary of state for war set up an expert commission to investigate dysentery and enteric fever.

Since I wrote about Zika in February, genome sequencing has shown that the virus has three lineages: West African, East African and Asian. Analysis of a 1966 Malaysian strain and a 1968 Nigerian one point to an Asian origin for the Brazilian viruses; it is likely that Zika has been circulating in Brazil since 2013. The virus has been evolving in expected ways (its RNA genome has a high mutation rate); no change that could account for an enhanced ability to damage the brain has yet been found. None of these findings has hit the headlines.

In 2014 the prime minister commissioned Jim O’Neill to conduct a review and make recommendations to ‘defeat the rising threat of superbugs’. O’Neill’s final report, published on 19 May, predicted that superbugs could kill 10 million people a year by 2050, the equivalent of one person every three seconds, more than cancer, with a cumulative cost of around $100 trillion.

In its last week in print, the Independent carried a piece under the headline: ‘One more thing imperialism has to answer for: dysentery.’ It’s a striking statement, but is it true?