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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Health https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ BBC – Future – How can the malaria vaccine change the world's health?

BBC – Future – How can the malaria vaccine change the world's health?

"In every home three or four patients complained of an illness, severe headache, sweating, back pain and leg." After four or five relapses, headache and pain many patients with a coma muddling delirium, who end up in death, have been proud to be aged between five and 20 years old because they are far from the simplest of clinics, which means there is no possibility to be saved their lives, they die like bees in a whisper rest. "This is an extract from a report in the 1958 epidemic of Ethiopia's malaria that killed about 150,000 people at one time, but it may is from the last days of the Roman Empire, whose fall is associated with disease, or Ancient Egypt, or India in the 19th Century, or in fact is the majority of all time history.

Malaria is a curse of mankind. This is one of the eldest of human diseases, affecting the earliest ancestors, influencing our recent evolution, and causing approximately half of all deaths since the Age of Age. Today, nearly half of the world's population is at risk from malaria ̵

1; it kills more than 400,000 people a year, most of them in Africa, where one child dies every two minutes from the disease. But now hope is raised by the end of evil: the first malaria vaccine was launched in immunization programs in Malawi, Ghana and Kenya.

The new vaccine was developed by GlaxoSmithKline in support of the Bill & Melinda Gates Foundation, and others including the World Health Organization (WHO) and Gavi, the worldwide vaccine alliance. It took 32 years of research, and costs over $ 700m (£ 552m).

Trials show that only 40% are effective in preventing illness for four years. It is as effective as influenza vaccine, but less than 97% effective vaccine in diphtheria. However, this may have been the most significant win in our malaria war for decades, preventing thousands of deaths and reducing the burden on the socio-economic burden of experiencing or caring for a fatal person ill. Public health officials in Africa allow themselves to be excited about the almost unexpected hope of illness.

I did not think that there would be a vaccine in my life, but now we have a chance – Anthony Nsiah-Asare, director general of Ghana Health Service

"I did not think there would be a vaccine in my life, but now we have the opportunity, "says Anthony Nsiah-Asare, director general of the Ghana Health Service, who works with the implementation of the vaccine. "We have seen how it was removed from certain continents, so it's possible in Africa, and now we have this true hope."

Although it is possible, we are sure that such an enemy is not easy to beat – after all, it has spent thousands of years adjusting to comfortable reliance on human troops.

Malaria is a disease caused by a protozoan called plasmodium – essentially a single parasite animal that moves around the human food diet. Among the five different types of malaria that affect people, Plasmodium falciparum is the most fatal. Plasmodium spreads to the bite of the Anopheles mosquito, which transmits infected blood between humans. As a result, diseases in the environment where mosquitoes grow: the conditions of hot conditions with pooled water (the larvae of mosquitoes live in water and can not survive until adulthood without it), and many human blood for adult insects are festivals. The poor maintenance of drainage over crowded heavens around Rome is ideal, and deadly malaria epidemics have caused anorexia and killed children and adults, who, some historians have believe, eventually brought the Empire to the knees.

Even colder places, like Britain, are not always saved. Malaria, known as fever, is common in the southern part of the country for centuries, the massacre, and associated with bad air – or "mal aria" in Latin – from the marshes. The last indigenous are two Londoners, who have contracted Stockwell's disease recently in 1953.

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In the 1890s only a military doctor living in India noticed a mosquito and managed to prove that malaria was caused by a parasite spreading insects. European nations and others who take malaria are often made to change the environment – such as drugs, cleaning slums and other mosquito breeding sites, and using insecticides and a standing water. Better countries can eliminate pain through these methods, even in tropical latitudes where mosquitoes are most effective, such as Singapore.

However, in sub-Saharan Africa, where it was first grown, the disease has proven to be the most prevalent, killing history of half of children before the age of five. It was thought that malaria had first reached the epidemic proportions on the arrival of agriculture (and thus, land clearing) on ​​the continent, about 4,000 to 5,000 years ago – with malignant references in the Sumerian and Egyptian texts from 4,000 years ago. Since then, people and protozoa have maintained an intimate relationship.

Our human bodies have not taken this attack without hardiness. Over generations, affected populations have changed many strategies to mislead plasmodium, including changes in hemoglobin-shaped blood oxygen-carrying, often large amounts. For example, Sickle-cell anemia and thalassemia, both cause weakness and reducing life expectancy, but also protect the possible malicious infections of malaria, and are therefore more common in exposed populations.

proves a tough enemy for our immune system. That is because it is a more complex organism than bacteria and viruses our bodies usually fight. It is highly susceptible, so when our immune system begins identifying and attacking its molecular coating (antigens), the parasite produces different arrangements to bring us back.

The most effective defense of plasmodium is the complex lifecycle, where the organism morphs in different forms while inside our body, each presents different antigens our immune system has changed.

A bite from an infected mosquito identifies around 100 sporozoites in the victim's blood, which spreads only 30 minutes before moving to the liver, where they are hiding in its cells. Here, they multiply in the next 7-10 days, changing the merozoites, which damage the liver cells in protective cements, which evade the immune system. Once in the blood vessels, ammunitions are spreading and merozoites invade red blood cells, rapid and exponential multiplying and destroying blood cells.

The destructive "stage of blood" causes periodic fever-related malaria. Some of the merozoites then morph in the sexual forms of the parasite, male and female gametes. They are then ingested by a mosquito bite and, inside the insect's stomach, morph into ookinetes, which burrow into the gut walls and form oocysts. Within the oocyst, new sporozoites form, ready to spread mosquitoes to a new victim.

Sporozoites are only short in the blood and there are very few of them for the immune system to be able to recognize and mount an attack, and at the time the merozoites are moving, the parasite is extremely damaging and rapidly changing the immune system to reactivate to gain control. Once our bodies manage a response against a type of antigen among merozoites, the exponential burst of new forms outdoes this effort.

Thus in order to combat every new infection, a human host should mount a new and "lame" immune response to each antigenically distinct parasite in the mosquito bite, as well as new antigens that emerge during of the course of infection. As a result, a malicious infection can last for many months to many years. When an adequate broad spectrum of parasites strain experiences any immunity achieved.

Individuals exposed to endemic malaria face a long and dangerous battle to achieve even partial malaria maladies, and the weakest is the youngest. Small children seem to have a low capacity to get effective anti-malarial disease of any kind, but anyone who has not experienced an endemic strain of infection is also facing a major threat.

Protection from invaders

History, the protected Africans from colonial expansion. Europeans coming to the continent were killed by so many numbers that the coast of Sierra Leone was known as the White Tomb. Malarial mortality rates above 50% per year of engagement are the norms in West African coastlines. And, despite the huge amount of achieving immunity, it's easy to lose – a few months without reinfection is enough to leave an individual vulnerable to the full effect of malaria.

As a result, areas experiencing more frequent epidemic diseases in the individual population can record higher mortality rates than those which are indigenous. Everyone who speaks to me in Ghana is aware of the protective benefits that have regular infections that they can experience. They are enhanced by treating medicines.

The first effective treatment came from Peru. Malaria is introduced to the Americas probably in the West African slave transport, and the natives follow the treatment of fevers on the bark of the tree of Cinchona. In the mid-19th century, quinine, an active part of antimalarial skin, has been widely used in Europe in West Africa, rapidly reducing mortality by more than 75%.

In the 20th Century, a new chloroquine drug has been effective in the treatment and prevention of malaria, and this, in addition to the use of insecticides, such as DDT, is revolutionary. The insides and outsides of human spaces were sprayed, and death malaria plummeted. As Europe and North America have increased in abundance, fewer people have been exposed to infection, and the whole nation has been declared sick. In the 1950s, the dream of global eradication of malaria seemed to be a decade or two.

The purpose of the depression is quietly eliminated by the purpose of disease management, with the idea that malaria will remain with us forever

never realized. In decades, malaria parasites have developed resistance to chloroquine, DDT and other drugs. The society has been against insecticides due to their environmental and health impacts, which prohibit DDT, and large human populations in the tropics have remained caught in poor mosquito conditions. However, the achievement is an unparalleled reduction in illness and mortality due to malaria in the vast tropical and subtropical regions of the world. New drugs, such as artemisinin, discovered in 1972 and used in combination with other anti-malaria to reduce the parasite resistance, make malaria a chronic rather than lethal disease for many who have access theirs.

The purpose of eradication is quietly eclipsed by the purpose of disease management, in a sense that the malaria will remain with us forever.

However, even if malaria does not kill, repeated infections cause anemia, weakness, body disorders, dysfunction and disorders of vital organs, spleen enlargement, infertility, loss of illumination, loss of thought, loss of loneliness and feelings of other illness. Malaria reduces the length and quality of life, and in addition it draws a large number of social and economic.

Care for relatives and unable to work because of the humiliation of households in difficulties – economists calculate that 1% negative growth each year in Africa in the last half century can be attributed to malaria. Malaria is a painful illness but a disease that is harmful.

Controls for factors such as tropical location, colonial history, and geographical isolation, countries with intensive malaria have income levels in 1995 of only 33% of countries without malaria, not the nations are in Africa.

The burning of injustice on the continent of people that has been halted by this ancient plague continues to rely on hopes for solutions. Governments and philanthropists have poured billions in effort – last year, Bill Gates, who made a fight against malaria a personal crusade, announced an additional $ 4bn (£ 3.16bn) in the fund from on its foundation and other donors. Most of these have come to the most effective mosquito protection strategies, including providing bednets that are considered insecticide and removal of breeding grounds by removing or pouring standing water . But the hope of a vaccine goes back to the background.

There have been many attempts at the manufacture of one – all of which are lacking in some stages of clinical trials, which fall into both barriers as our immune system: the tricky, plasmodium balancing.

Licensing of the first proven malaria vaccine, called RTS-S, adds to our defensive arsenal and marks a significant step in the fight against disease, enabling displacement hopes to be restored. The vaccine exposes the body to one of the largest antigens used in sporozoites, which are only present in the blood before they themselves are thrown into the liver.

However, hope is that by taking the immune system in attack at this stage, deadly febrile merozoites stages will be avoided in the blood. During its long development, a hepatitis B vaccine was created, making a highly effective immune response, so the malicious researchers decided to add it to antigen sporozoite to become the immune system's strength. It ends – previous trials have found that it is 87% effective in removing sporazoites.

The problem is if a sporozoite avoids the liver and enters the blood phase as a merozoite, it has the ability to multiply exponentially and produce malaria. For this reason, clinical trials found that the vaccine was only 50% effective in preventing malaria within a year after vaccination, and it fell to 40% after four years.

This is an expensive, processed process, not without critics, who believe that money may be better spent on improved drug treatment access and bednets. However, malaria proves a horrible burden that even though it is somewhat underdeveloped, however, the vaccine has the potential to prevent many thousands of deaths.

WHO is positive in the project, with Matshidiso Moeti, Director of the WHO Region for Africa, saying: "Inovation will allow us to cope with malarial parasites." However, its actions are cautious, and instead of a broad continent, the project will take effect in stages, beginning with pilot districts in Ghana, Malawi and Kenya this spring. The four doses required for immunity are added to the regular vaccination schedule schedule for infants in these countries, all with well-functioning public health care systems. And accompanying initiative education encourages the public to continue using their other prevention strategies, giving the program the best opportunity. If this is effective, the vaccine will be global for two years & # 39 ;.

"It's a very special moment for us to see the immunization program begin. It's very emotional to see our lives," says Lode Schuerman, director of global medical activities at GSK, who spent of the past decade in the development of the vaccine. "It should be done to eliminate malaria."

The danger, he warns, is to choose interventions that reduce the scope of the disease in some areas, but allow it to return to the deadly power against the non-survivors. "I know the parasite, I'll use everything we have at once and for all these addresses to bear," he said.

This is just the beginning of what can be a new era of victorious fight against malaria. Many other vaccines are also in the pipeline, including one that uses full sporozoite (irradiated for safety) and should be injected into one vein, but 100% effective in laboratory testing – it enters clinical trials next year on the island of Bioko of Ekwatorial Guinea.

Other researchers target mosquitoes playing crucial role in the spread of plasmodium, looking at ways to change genetic insects so they become thin or not able to carry parasites. Last year, saw the first release of GM mosquitoes on the continent, with the introduction of 10,000 insects in Burkino Faso bringing mutations to sterile women.

In Ghana, vaccination clinics begin to start malarial infections with other diseases, long lost, such as polio and diphtheria. The warm air is thick with humidity and humming the mosquito. Anthony Nsiah-Asare took away, and laughed when I asked if he had malaria. "No one is here for more than a month has not been infected," he said. "But now we will have a vaccination. Now we see the end of malaria."

Gaia Vince is a radio broadcaster and broadcaster specializing in science, environment and issues in society. His first book, Anthropocene Adventures: A Planet Travel Journey We did, the 2015 Royal Society Winton Prize won for Science Books. His next book, Transcendence will be published in autumn 2019. Gaia blogs at WanderingGaia.com and tweets at @WanderingGaia .

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