Johannesburg — THERE has been much written and said in the media recently about the successful development of a malaria vaccine and, considering the human misery and economic costs the disease continues to cause, the developments should be welcomed.
The vaccine showing the most promise (known by its laboratory name of RTS,S) was first formulated more than 20 years ago and has been used in trials since 1992, but due to the tricky nature of the parasite, which is constantly evolving, outwitting modern medicine and the human immune system, the development of a successful vaccine has been a slow process of trial and error. Breakthroughs such as this lead many to postulate about the possibilities of eradicating malaria. Having a grand goal such as eradication in mind is good, but we can and should learn from history and previous efforts at eradication before we get our hopes too high.
The World Health Organisation estimates that malaria claims more than 1-million lives every year and causes between 300-million and 500-million people to become acutely sick. Most cases and deaths occur in sub-Saharan Africa, home to the most efficient malaria-carrying mosquito species, which feeds almost exclusively on human beings, as well as the most deadly strain of the malaria parasite. The disease is considered to cost Africa at least $12bn every year in lost productivity and other direct costs of dealing with the disease.
Malaria was a serious global health concern until the mid-20th century. In the 1940s, the successful application of DDT as part of indoor residual spraying (IRS) programmes, coupled with the effectiveness of antimalarial drugs such as chloroquine, gave countries the impetus to attempt to eradicate the disease. In 1955, the Eighth World Health Assembly resolved to begin a worldwide eradication campaign, but Africa was largely overlooked and excluded from the campaign .
Ultimately it was the countries that were developing and becoming wealthy that successfully managed to eradicate malaria most rapidly and have subsequently kept it at bay. From the late 1800s, malaria declined in most of Europe and the US because mosquito-breeding areas were being drained for farmland. People could afford better housing with windows, screens and shutters, and to treat and kill off the deadly parasites.
African nations already have the tools to effectively control the disease. C ommunities have effective insecticides at their disposal, as well as drugs to clear the parasites from their bodies. An effective vaccination should thus be seen as a complement to our arsenal to fight the disease.
The latest trials of the RTS,S vaccine have provided a ray of hope for many. The trials were conducted among 214 babies in rural Mozambique. Some of the babies were given the RTS,S vaccine and others were given a standard hepatitis B vaccine at ages 10, 14 and 18 weeks. The babies who received RTS,S were 65% less likely to contract malaria compared with their counterparts who received the control hepatitis B vaccine. These encouraging results came off the back of tests that were conducted in Mozambique in 2004 among older children (aged between one and four years) where the vaccine was "only" 45% effective.
However, politicians and malaria programme managers wishing to catch this rising star need to be acutely aware that in reality we are not operating in a frictionless environment and there are serious obstacles to the roll-out and successful implementation of a vaccine. The obstacles are similar to those plaguing the effectiveness of malaria control programmes -- weak infrastructure, bureaucratic hurdles and the stark reality of millions of poor individuals who can barely sustain themselves, let alone spend money on measures to control and treat the disease.
Research into new and essential tools to fight malaria in Africa must continue. We have a long, hard road to travel before eradication will be in sight and, if history is anything to go by, eradication will have more to do with African politics and economics than with specific technologies.
In the short run, countries must continue to strive towards a comprehensive malaria control programme. This implies an acute understanding of the nature of the vectors as well as an understanding of what measures are needed to control the parasite most effectively, in terms of reducing levels of morbidity and mortality.
In the long run, economic development will be the major driving factor behind the elimination campaign and the lack of infrastructure and bureaucratic hurdles will continue to hamper control efforts -- making malaria control campaigns extremely cumbersome but not impossible.
So will it be possible to eliminate malaria? Yes, of course, one day it will be possible, but given the levels of economic growth and the expected future levels, elimination (in the sense of zero transmission) in sub-Saharan Africa seems unlikely to occur in our lifetime, even if a vaccine were to be made available for mass production tomorrow.
Urbach is a director of the health advocacy group, Africa Fighting Malaria.