Steve Connor: The results so far arec good, but there's still a long way to go before an effective malaria vaccine is available
Steve Connor is the Science Editor of The Independent. He has won many awards for his journalism, including five-times winner of the prestigious British science writers’ award; the David Perlman Award of the American Geophysical Union; twice commended as specialist journalist of the year in the UK Press Awards; UK health journalist of the year and a special merit award of the European School of Oncology for his investigative journalism. He has a degree in zoology from the University of Oxford and has a special interest in genetics and medical science, human evolution and origins, climate change and the environment.
Tuesday 08 October 2013
The vaccine known as "RTS,S", made by GlaxoSmithKline, was the first "candidate" vaccine against malaria and was initially developed as long ago as 1987. This fact alone indicates just how difficult and tortuous it is to manufacture a safe, reliable and effective vaccine against the malaria parasite.
Malaria is caused by a relatively sophisticated single-celled microbe, Plasmodium falciparum, with a complex life-cycle. The parasite can change its outer protein coat to confuse the body's immune defences and so effectively presents a constantly moving target for the vaccine "bullet".
In addition, the Plasmodium parasite can hide within the blood cells of the body, making it virtually unrecognisable to the immune defences that a vaccine stimulates. The microbe also flips from one stage of its life-cycle to another and infects more than one set of tissues in the body.
Nevertheless, RTS,S is the first malaria candidate vaccine - and there have been many over the decades - to reach the stage of widespread testing at the most advanced phase of clinical trials. It is designed to prevent the Plasmodium parasite from infecting, maturing and multiplying in the liver, from where the parasite will re-enter the bloodstream to infect red blood cells and so cause symptoms.
The vaccine is supposed to work by stimulating both arms of the immune system, the free-floating antibodies - the specialised proteins of the immune defences - and the killer T-cells of the blood which are designed to seek out and destroy alien invaders.
This phase III study, based on 15,000 immunised children, is now at the 18-month stage following vaccination. The results are impressive, with nearly 50 per cent protection, which although not brilliant will be good enough to make a big difference in fighting a disease that still kills more than 600,000 people a year - most of them children.
However, this trial still has some way to go before it concludes. The efficacy of the vaccine for infants and young children could well go down further still - it was higher at the 12-month stage - which would raise serious questions about its usefulness.
Further findings from the 32-month stage of follow-up, and the impact of a booster given after 18 months, will be made available next year. We should know then whether we really do have an effective vaccine against malaria.
- 1 This 'woman calls police to order pizza' story isn't going where you're expecting
- 2 Axe wielding man shot dead after attacking four New York policemen on busy street
- 3 Watch what happened when food critics were unknowingly served McDonald's
- 4 Jimmy Carr's Oscar Pistorius joke goes a bit too far at the Q Awards
- 5 Ottawa shootings: Bruce MacKinnon's cartoon is the perfect tribute to soldier Nathan Cirillo
Renee Zellweger on plastic surgery rumours: 'I'm living a more fulfilling life and I'm thrilled that perhaps it shows'
FCKH8: YouTube reinstates provocative anti-sexism video showing young girls swearing
Axe wielding man shot dead after attacking four New York policemen on busy street
This 'woman calls police to order pizza' story isn't going where you're expecting
McKamey Manor: This 'extreme' haunted house is the stuff of nightmares
Of course, teenage girls need role models – but not like beauty vlogger Zoella
Cameron is warned 'no possibility' of UK reducing immigration and that bid to bring in quota on migrant workers would be illegal
Support for EU membership 'at highest level since 1991' with most Brits wanting to stay 'in'
Thousands with degenerative conditions classified as 'fit to work in future' – despite no possibility of improvement
Attacks on 'Ukip Calypso' show how skewed people’s priorities are
London bus driver 'kicks gay couple off for kissing'
£40000 - £50000 Per Annum Excellent benefits: Clearwater People Solutions Ltd:...
£30000 - £35000 Per Annum Excellent benefits: Clearwater People Solutions Ltd:...
£35000 - £40000 Per Annum Excellent benefits: Clearwater People Solutions Ltd:...
£47,334 - £59,058 per annum: Coventry University: The Centre for Agroecology, ...