Malaria is one of the most deadly, and as a consequence one of the most feared, diseases, and has been for hundreds of years, even now well into the 21st century, killing more than 400,000 people a year, with a high proportion of that number sadly being infants, or babies. In advance of 40 million children live in areas of sub-Saharan Africa with high or moderate malaria transmission carried by mosquitoes, and studies have shown that one child under the age of five dies every 75 seconds from the effects of the dreaded disease; all this despite the use of bed nets, preventative drugs, and insecticide sprays, to try and keep it under control.
Now however, there is genuine belief that scientists may have found a way forward, leading to a point in the very near future where it will be possible to considerably reduce the deaths through the development of a new vaccine. Created at the Jenner Institute at Oxford University in the UK, initial trials have shown some extremely encouraging results. The laboratory where this vaccine was formulated was also the same place that so successfully worked on the AstraZeneca vaccine for COVID-19 coronavirus two years ago, so a similar outcome is eagerly anticipated.
Successful trials
In the highly effective trials carried out in Nanoro, in the West African nation of Burkina Faso, three doses were given to 450 children and these were found to give 75 per cent protection for a full year, and furthermore, a booster was seen to extend that cover for another 12 months, this time with up to 80 per cent protection against horrific disease.
Professor’s high hopes
Professor Adrian Hill, director of the Institute, who led the research pointed out that people have been trying to make malaria vaccines for over a century, adding that around 140 different malaria vaccines have gone into arms during that time, but stated excitingly: “We think these data are the best yet of any malaria vaccine, with what looks to be long-lasting high efficacy.”
He also predicted that the vaccine, called R21, could be deployed into use and saving lives, possibly from as early as next year, as crucially it will be very cheap to manufacture, less than £5 each, and that they already have a deal to make more than 200 million doses a year with the serum institute in India, the world’s biggest vaccine manufacturers, and that they would immediately be accessible to many of the worlds least developed countries.
Following on from GSK
Just last year the World Health Organization (WHO) gave the go ahead for a vaccine, the very first one developed, by global pharmaceutical giant Glaxo-Smith-Kline (GSK) to be used across Africa.
However, the Oxford team claim their approach is more effective and can be manufactured on a far greater scale. The team have already begun the process of getting their vaccine approved in the next few weeks, but a final decision will hinge on the results of a larger trial of 4,800 children, due before the end of the year.
Potential world changing effectiveness
For Professor Katie Ewer this was the 14th vaccine that she has worked on at Oxford, but was quick to highlight that this was much harder than anything previous because the malaria parasite is, in her words, “spectacularly complex and elusive”, adding that it is a constantly moving target, shifting forms inside the body, which make it hard to immunise against. For those reasons she said it was “incredibly gratifying” to get this far and made the point that “The potential achievement that this vaccine could have if it is rolled out, could be really world-changing.”
Why is the R21 better than the vaccine of GSK?
There are distinctive similarities between the currently approved vaccine made by GSK and the new R21created at Oxford, with both of them targetting the first stage of the parasite’s lifecycle, by intercepting it before it gets to the liver and starts to establish a foothold in the body. Each vaccine also are built using a combination of proteins from the malaria parasite and the hepatitis B virus, but the Oxford version has a higher proportion of malaria proteins. The team believe that this assists the immune system to enable it to focus on malaria, rather than the hepatitis.
Oxford can easily surpass GSK supplying figures
The GSK vaccine known as Mosquirix, has shown itself to be 44 per cent effective over the course of one year, which although respectable, is considerably below the projections from Oxford. GSK has committed to produce up to 15 million doses of their vaccine through to 2028, well below the 100 million doses a year that the WHO has said is needed long-term; but GSK has already said it cannot meet such a vast demand, when taking into account where their funds stand at present.
How is Malaria transmitted?
Malaria is an acute febrile illness caused by Plasmodium parasites, which are spread to people through the bites of infected female Anopheles mosquitoes. Just one bite is enough to cause potentially fatal consequences. There are five parasite species that cause malaria in humans, with the most deadly being one referred to as P. falciparum and it is this particular variant that is most prevalent on the African continent.
When a mosquito bites an infected person, a small amount of blood is taken which contains microscopic malaria parasites. Normally around one week later, when the mosquito takes its next blood meal, these parasites mix with the insect’s saliva and are injected into the person being bitten. Additionally, due to the fact that the malaria parasite is found in red blood cells of an infected person, the disease can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes, contaminated with blood.
So many different types of mosquito
For all the devastation these tiny insects cause worldwide it is possibly surprising to learn that they only actually survive as adults for between two and four weeks, depending upon the species, temperature, and humidity of their habitat. There are incredibly over 3,500 types of mosquitoes and they can survive indoors or outdoors.
Not all mosquito bite and there are others that do bite but do not spread germs. Unfortunately the vast majority do like to bite and the most common reaction is a swelling around the affected area, which will itch and possibly be quite sore. Interestingly, it is only the female mosquitoes that bite people and animals to enable them to get a blood meal, which they require to produce eggs. Although they are mostly associated with biting at night, they are just as likely to have a “feast” during the day; it just seems to be worse at night as people tend to be lying still.
Who are most at risk from malaria?
The fact of the matter is literally anybody can contract malaria, but undoubtedly there are several groups of people who are more at risk. Many African countries, especially those south of the Sahara desert where mosquito numbers are most prevalent, are susceptible to the disease. Also people who have little or no immunity to malaria, such as young children and pregnant women, the elderly and people passing through malaria hotspots from areas free of the threat. The vast majority of deaths occur in children under 5 years of age.
What are the Symptoms of malaria?
Malaria is not always that easy to diagnose straight away, but some of the obvious signs are: a high feverish temperature, headaches, chills, lethargy, tiredness, nausea, diarrhoea, loss of appetite, aching muscles, yellow skin and whites of the eyes, and respiratory difficulties. The problem is they can occur anywhere between one and three weeks after being bitten, although in some cases it can stretch into months after the bite.
In actual fact the parasite can lay dormant inside somebody’s liver for up to four years before coming out of “hibernation” and invading a person’s red blood cells. Left untreated it can progress to severe illness, causing the likes of kidney failure, seizures, mental confusion, coma, and even death very quickly, once it has taken hold.
Where is the disease most commonly found?
Malaria would typically be found in tropical and subtropical countries. Higher temperatures allow the Anopheles mosquito to thrive. Their parasites need warmth to complete their growth before they are mature enough to be transmitted to humans. Across the globe malaria occurs in more than 100 countries and territories, meaning incredibly that around half of the world’s population is at genuine risk. Large areas of Africa and South Asia and parts of Central and South America, the Caribbean, Southeast Asia, the Middle East, and Oceania are considered areas where malaria transmission most widely occurs.
Is the disease contagious?
The one good thing about this awful disease is that it is not contagious. It cannot be spread from person to person like a cold or the flu, and neither can it be sexually transmitted. Any kind of casual contact with malaria-infected person is nothing to be alarmed about, it is not possible to be passed on.
Which area has most cases?
There are almost a quarter of a million cases of malaria every year, with around 25 per cent resulting in loss of life, although recent figures have been distorted by the effects of the pandemic too. The sub-Saharan area of Africa sees by far the greatest number of deaths, with four countries: Nigeria, the Democratic Republic of the Congo, United Republic of Tanzania, and Mozambique, accounting for just over half of all malaria deaths worldwide. Which is why this Oxford breakthrough is so important.
Possible 70 per cent reduction in deaths by end of decade
According to Professor Hill the complicated structure and lifecycle of the malaria parasite has for a long time hindered efforts to develop vaccines, but said he felt that this development has fantastic potential and said that: “If we can do it at a grand scale we really could be looking at a substantial reduction in the burden of malaria deaths and disease by 2030, by possibly as much as 70 per cent.” He continued to say that they wanted to add a malaria vaccine on top of bed nets, spraying, and drug preventive treatment, and hopefully get to a far better place in terms of the effects malaria has on the world.
As always cash is the key
The stumbling block, as is so often the case, could be money. Scientists have warned that the benefits of the vaccine may not be realised if richer nations waver in their funding for malaria controls. The UK and United States have in the past been major contributors, but for the UK in particular, the financial crisis that it is currently in the grips of, could see funds slashed.
No turning back
Professor Azra Ghani, who is the chair in infectious disease epidemiology at Imperial College London, warned that without investment there was a real prospect of losing any gains made and instead of a reduction, there could in actual fact be a resurgence. He said the fight against malaria is at a crossroads and whilst acknowledging the great strides being made with the Oxford vaccine, it required everyone to continue on the current path, with significant backing still needed to ensure sufficient funds were in place to maintain the fight.
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