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We next few achieve an effective vaccine?


Epidemiolgicamente and inmunolgicamente complex disease such as malaria, can not be deleted with a single procedure

The recent news about the & # 39; is a vaccine against malaria. There is a widespread opinion, contributed to the multinational farmaceticas and his staff (including physicians, prescribers, researchers, mdicas companies and regulatory institutions), that all the vaccine & # 39 are very effective and safe for the prevention of diseases and eliminate epidemics, the idea, which contributes to their business interests through extensive vacunacin program. Nevertheless, we regret that this is not always the case. There is a very effective and safe vaccines, while others with a & # 39 are less effective and less safe. malaria cases or malaria vaccine paradigm is difficult to achieve, so that the scientific community even decades, explores without obtaining satisfactory results. It is true that you have invested millions of dollars in order STE and developed various types of vaccines, but to date none of which no more than partial results and passengers. From this point of view, and in the news, not to give up on the roof and the confidence of the eradication of malaria from the vaccine has been achieved in other pests that have plagued mankind, such as smallpox or polio. On the contrary, although we have a vaccine, we must continue to carry out all possible malaria control measures, while not forgetting that the vast majority of epidemics are directly related to social determinants and economic, so what's going on in poor countries, as long as the neoliberal neocolonialism infrastructure of private health care and a healthy environment. Mediterrneos remember that all countries, Spain and Italy among them has not suffered the scourge of malaria, yet not too far from few.

Malaria is a & # 39 is a potentially fatal disease caused by parasites that are transmitted to humans through the bite of infected Anopheles mosquitoes. This can be prevented and treated.[i]

In 2017, 219 million cases of malaria have been evaluated in 87 countries. The estimated number of deaths from malaria was 435,000 in 2017. Eleven countries, 10 countries in sub-Saharan Africa and India, accounted for most of all malaria cases and deaths worldwide.

Fifteen countries in sub-Saharan Africa and India have experienced about 80% of the global burden of malaria. Five countries account for almost half of all cases of malaria around the world: Nigeria (25%), the Democratic Republic of the Congo (11%), Mozambique (5%), India (4%) and Uganda (4%).

Regina WHO Africa has a disproportionate share of the global burden of malaria. In 2017, the region was home to 92% of cases of malaria and 93% of deaths from malaria.

according to World Report 2018 Malaria[ii] the world does not currently going to achieve two stages of 2020 criticism of the World Malaria Control Technician strategy 2016-2030 (GTS) WHO: reducing mortality and morbidity due to malaria by at least 40% until 2020, because the key to coverage prevention and treatment of malaria, such as treated nets (ITNs) and drug antipaldicos network intervention only slightly improved since 2015.

PROGRESS malaria

Access to health care with

Diagnosis and treatment of Express the most effective way to prevent a mild case of malaria is becoming a serious illness and death.

According to national household surveys conducted in 19 countries in sub-Saharan Africa from 2015 to 2017, a high proportion of febrile children received no attention Mdica.

Diagnosis and treatment

They were valued at 276 million rapid diagnostic tests (TDA) worldwide in 2017. The bulk of the CCT (66%) were detected only tests P. falciparum and countries in sub-Saharan Africa have been provided. Nevertheless, about 30% of patients treated with these have not been tested for malaria.

Between 20102017 2740000000000 therapy treatment based on artemisinin combinations (ACT), pay more attention to patients with positive test results were obtained malaria.

Most of the research conducted in the period from 2010 to 2017 shows that the TSA remain in force, with the pace of the overall efficiency of more than 95% outside of the Greater Mekong Subregion, where resistance.

19 based on household surveys in countries in sub-Saharan Africa between 2015 and 2017, share of children under the age of 5 years with fever who received SB antimalrico drug was only 29%

vector head

Half of the people at risk of malaria in Africa sleeping under insecticide nets (ITNs). However, the coverage has been stagnant since 2016, staying away from the goal of universal coverage.

Closed residual fumigation (IRS), a method of preventing, comprising spraying the interior walls of houses with insecticides significantly var & # 39; iruetstsa, depending on the cost of chemicals, operational strategies.

Resistance to four kinds of common insecticides (pyrethroids, organochlorine compounds, carbamate and organophosphate) to & # 39 is widespread in all the main vectors of malaria in the WHO regions of Africa, America, Southeast Asia, the eastern Mediterranean and the Pacific ocean Western.

preventive treatment


In order to protect women in areas of moderate to high malaria transmission in Africa, WHO recommends intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine antimalrico drugs.

Among the 33 African countries that provided approximately 22% of eligible pregnant women received the recommended 3 or more doses PPLba.


In 2017, 15.7 million children in 12 countries of the Sahel subregion in Africa were protected by quimioprevencin programs (SMC) of the season.

However, about 13.6 million children who could benefit from quimioprevencin were not covered, mainly due to the continued growth of the malaria in the countries with the highest burden of disease and insufficient international and national funds.

painter vaccine

From these positive results in a phase III trial of the vaccine, given limited effectiveness obtained during the early stages of testing, antimalrica vacunacin measure will add more have already been developed, such as mosquito nets, insecticide and quick and appropriate treatment of patients with a diagnosis of malaria.

An effective vaccine for protection, at least, peditrica population highly endemic areas will be the key to facilitate the fight against malaria and to move in the direction of further liquidation. Nevertheless, its development with the & # 39 is a challenging puzzle game that puts a lot of scientific problems. From the perspective of the immune parasite is of great complexity, we are still partial and insufficient knowledge. The parasite looks antgenos stretching along the different stages of their life cycle, and in respect of which requires consistent and Chained immune responses, and many parasitic proteins show great polymorphism. Our knowledge of the immunity that develops from malaria & # 39 is very limited and incomplete, and in contrast to other diseases, still have not found a good immune correlate of protection[iii].

NEWS: The pilot test should be performed GSK laboratory[iv], Pharmaceutical development of RTS, S

Research for the development of these vaccines have aadida difficulties that there are no relevant animal models, and that the only way to see its effectiveness testing clnicos malaria-endemic areas. Despite these significant challenges, there are reasons for optimism, as the most advanced vaccine candidate is called RTS, S (On the basis of fusion antgeno circumsporozoite surface with a surface antgeno hepatitis B, formulated with AS01 potent adjuvants) he has reached the last stage (III) prior to recording.

In clnicos trial, RTS, S vaccine has consistently demonstrated a moderate but constant efficiency for a long time, which invites us to think that the development of clnico effective vaccine against malaria is becoming increasingly close to reality most in need in areas endemic for shares may bring favor.

The efficacy and safety of this compound in the pediatric population in malaria-endemic areas, should add their encouraging results in more severe forms of the disease. The vaccine may be administered in the frames expanded program installed WHO[v].

To date, several vaccine trials clnicos was carried out in countries in sub-Saharan Africa, are always limited results[vi]

In recent years, multinational state farmacetica GSK I am having donated 10 million units this pilot with African children why Sern immunized 360,000 children from Malawi today and in the coming months in Ghana and Kenya

The vaccine is designed to dispense a dose of four children under the age of two years: the first three doses of five to nine months, and the last on the second year.

The results of the phase II trial

Phase II trials, initiated in 2003 in southern Mozambique, demonstrated the feasibility of the introduction of a malaria vaccine for children. The results of this study, led by Dr. Pedro Alonso in Research Health Center Manhia in conjunction with Center for International Health Research (CRESIB, Hospital Clnic Barcelona) They have shown the effectiveness of RTS, S at least 18 months, a decline of 35% in malaria clinic and 49% of severe malaria. Data concerning the second study in infants showed that in 2007, after a full cycle of shots in infants, then RTS, S This is a 65% infection within three months of observation. It is important to note that in addition to the fact that the vaccine is a promising safety and tolerability profile similar to the standard vaccine is typically administered in a child Inmunizacin expansion program of the World Health Organization.

Clnicos pretest with RTS, S

Clnico the first Phase III trial, which evaluates malaria vaccine Complet in December 2013 to 11 on the & # 39; sites in seven countries in sub-Saharan Africa. A systematic review of data evalu Phase I studies involving adult-III and adult malaria-free, children and babies endmicos malaria protection in countries in sub-Saharan Africa.

test results[vii] were AS01 malaria RTS, S / prevent many cases of severe and clinics for 18 months after the administration of 3 doses of vaccine, with the greatest impact in areas with high incidence of malaria. Vaccine efficacy (VE) was higher in children than in children, but even the modest level VE, the number of cases of malaria prevention was significant. RTS, S / AS01 can be an important contribution to the monitoring of malaria in Africa adicin.

Prximamente if the vaccine could be available in the market, other strategies must address the problem of how optimize the effectiveness of the vaccine and the implementation of RTS, S / AS01 in the framework of the measures set out in the fight against malaria.

The cost of the vaccine GSK

While SPF 66 vaccine, which is trying to get Patarroyo will cost the equivalent of the cost of production, it is estimated that about 10 cntimos still do not know what will be Rs price, S GSK, or to be paid, and that depends on the agreements reached between those who developed and institutions interested in its distribution among the population at risk of malaria, as the government most affected countries and international organizations that contribute to inmunizacin of disease transmission.

Patarroyo vaccine

Colombian immunologist Manuel Elkin Patarroyo, The Discoverer of the first vaccine against malaria, it was announced in January 2018 Formal delivery of an improved version with an efficiency close to 100%.

Patarroyo has been awarded the Peace Prize as the Prince of Asturias Scientific and Technical Research (1994), and in the same year with the Robert Koch, the most prestigious scientific galardn Germany.

After a relatively long period of many attempts to pass parasites models, which were varied, and thus, difciles interpret rich media advertisement in tests with the substance Manuel Patarroyo ProVoc many groups, in turn, to experiment with people. Fortunately, research in this area has benefited from recent advances in vacunologa, especially in connection with various types of presentation antgenos, and the knowledge gained in recent years on the biology of the parasite and the immune reactions of the parasite.

Malaria vaccine Future

By Ambroise Thomas P.[viii] In a number of countries in South America and East Africa, vaccine trials using sinttico antgeno an SPF 66, it is still modest, but their credit will be the first successful malaria vaccine in humans. In addition, these results have been evaluated for their impact on morbidity and not only parasitaemia. Some important progress, but it was a crucial step. In addition, in the near future and other probarn vaccines. They vary in purpose or concept, especially for anti-DNA vaccines. One or more effective vaccines should be made available in the coming years. Nevertheless, one can not determine the length of the waiting period.

It is impossible to give this vaccine all hope to eliminate or control malaria in endemic areas. Epidemiolgicamente and inmunolgicamente complex disease like malaria can not be deleted with a single procedure. Success will be obtained by judicious use of the amount of funds which have to date, including vector control to combat and protection, prevention of drug and drug therapy, in addition to the vaccine if it is available.

Jorge Barrn, medical microbilogo Osalde member

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