It looks ingenious. If you can't eradicate malaria in humans, why not do so in mosquitoes? It would accomplish a goal of which scientists hardly dared dream: a malaria-free world.
The achievement of Michael Riehle and his team at the University of Arizona is impressive. But by their own admission, they have done the easy bit – create a genetically modified mosquito that cannot transmit malaria.
To help with controlling the disease, the GM mosquito must first be proved safe for release into the wild and, second, must be given some advantage that renders it superior to natural populations so it can drive them out. That is much harder to do.
Despite these caveats, and the dreadful toll malaria still exacts, there are reasons to celebrate. Action against malaria – spraying of insecticide, distribution of bed nets and use of anti-malarial drugs – has increased dramatically in the last decade as global funding has expanded 50-fold to over $5bn in 2009. In coastal areas of Kenya, cases of severe malaria in children have fallen by 90 per cent in five years. Similar falls have been reported from other locations.
In certain islands in the Philippines, malaria has been eliminated. Mexico is said to be close to eradication, countries in South America are moving in the same direction and Morocco is expected to announce the end of the disease soon.
Sub-Saharan Africa, which bears 70 per cent of the disease burden, presents a much tougher challenge. But in the global malaria community – where gloom prevailed a decade ago – the buzzword now is elimination. As The Lancet noted this month, "previously cautious malariologists, released from a 40-year collective depression... have been invigorated".
Talk of elimination may be premature – the funds required to chase down the last few cases of a disease are several orders of magnitude higher than those needed to control it – as the polio eradication campaign has proved. But that we can envisage the end of a disease that still kills in biblical proportions is itself a remarkable advance.