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The World’s First Malaria Vaccine to Be Rolled Out in Ghana, Kenya and Malawi in 2018

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Image credit: Shutterstock

Malaria is one of the world’s most deadly diseases even though it is highly preventable and treatable. Malaria causes approximately 881,000 deaths every year, with nine out of ten deaths occurring in sub-Saharan Africa.

Effective control and treatment of malaria has been very challenging and efforts have been made to reduce the burden of malaria in an integrated approach that combines preventative measures, such as long-lasting insecticide-treated bed nets (LLINs) and indoor residual spraying (IRS), with improved access to effective anti-malarial drugs.

However, malaria is a disease that stems from and causes poverty, and many at-risk populations live in extremely destitute, remote areas. Poor, rural families are the least likely to have access to these preventative measures that are fundamental to malaria control, and may live kilometres from the nearest healthcare facility. They are also less able to afford treatment once infection has occurred.

In addition to the human cost of malaria, the economic burden of the disease is vast. It is estimated that malaria costs African countries more than US$12 billion every year in direct losses, even though the disease could be controlled for a fraction of that sum. For Nigeria alone the direct loss to the economy is estimated at GBP530 million annually.

Up to 40% of African health budgets are spent on malaria each year, and on average, a malaria-stricken family loses a quarter of its income through loss of earnings and the cost of treating and preventing the disease. Malaria causes an average loss of 1.3% of economic growth per year in Africa.

There is a ray of hope in Africa as the world first malaria vaccine is to be rolled out in Ghana, Kenya and Malawi in 2018. This injectable vaccine known as “RTS,S or Mosquirix” was developed by British drugmaker GlaxoSmithKline (GSK) and will be offered for babies and children in high risk areas as part of real life trials as reported by the World Health Organisation (WHO).

In clinical trials it is proved only partially effective, and it needs to be given in a four-dose schedule, but it is the first-regulator-approved vaccine against the mosquito- borne disease. The WHO, who is in process of assessing whether to add the shot to the core package of WHO-recommended measures for malaria prevention, has said it firsts wants to see the results of on-the ground testing in a pilot programme.

“Information gathered in the pilot will help us make decisions on the wider use of this vaccine,” Matshidiso Moeti, the WHO’s African regional director said in a statement as the three pilot countries were announced.

“Combined with existing malaria interventions, such a vaccine would have the potential to save tens of thousands of lives in Africa.”

Global efforts in the last 15 years cut the malaria toll by 62 percent between 2000 and 2015. The WHO pilot programme will assess whether the Mosquirix’s protective effect in children aged 5 to 17 months can be replicated in real life. It will also assess the feasibility of delivering the four doses needed and explore the vaccine’s potential role in reducing the number of children killed by the disease. 

The WHO said Malawi, Kenya and Ghana were chosen for the pilot due to several factors, including having high rates of malaria as well as good malaria programmes, wide use of bed-nets and well-functioning immunization programmes. 

Each of the three countries will decide on the districts and regions to be included in the pilots, the WHO said, with high malaria areas getting priority since these are where experts expect to see most benefit from the use of the vaccine.  The vaccine was developed by GSK in partnership with the non-profit PATH Malaria Vaccine Initiative and part-funded by the Bill & Melinda Gates Foundation.

The WHO said in November it had secured full funding for the first phase of the RTS,S pilots, with 15 million from the Global Fund to Fight AIDS, Tuberculosis and up to 27.5 million and 9.6 million respectively from the GAVI Vaccine Alliance and UNITAID for the first four years of the programme.

This significant development will help to address the continuing challenges presented by malaria in Africa in the years ahead and hopefully bring an end to this deadly disease.

Sources:

The Hindu, April 25, 2017. 

Kokwaro G. (2009) Ongoing challenges in the management of malaria. Malaria Journal, 8(Suppl 1):S2 doi:10.1186/1475-2875-8-S1-S2.

Why Pregnant Women Must Have Protected Sex and Avoid Mosquito Bite

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A baby born with microcephaly

The U.S. health agency says it is important for pregnant women to take safe sex precautions and avoid mosquito bite.

The Zika virus is causally linked to microcephaly, the birth defect that leads to abnormally small head size in infants, the U.S. Centers for Disease Control and Prevention declared Wednesday in The New England Journal of Medicine. The agency said it has not found any definitive new evidence but has weighed the accumulating data connecting the two conditions and concluded that it was solid enough to call causative.

Zika Fever

Zika infection known as Zika fever, often causes no or only mild symptoms, similar to a mild form of dengue fever. Common symptoms of infection with the virus include mild headaches, Maculopapular rash, fever, malaise, conjunctivitis, and joint pains.
The illness cannot be prevented by medications or vaccines. It is treated by rest.

Zika Virus

Zika virus got its name from the Zika forest of Uganda, where the virus was first isolated in 1947. Zika virus is related to Dengue, Yellow fever, and West Nile viruses.

Since the 1950s, Zika virus has been known to occur within a narrow equatorial belt from Africa to Asia. From the year 2013 – 2014, the virus spread eastward across the Pacific Ocean to French Polynesia, New Caledonia, the Cook Islands, and Easter Island, and in 2015 to Mexico, Central America, the Caribbean, and South America, where the Zika outbreak has reached pandemic levels.

Transmission by Mosquito

Zika is spread by daytime-active mosquitoes. It is primarily spread by the female Aedes aegypti mosquitoes .

Transmission Through Sex

Zika can be transmitted from a man to his sex partners. As of April 2016 sexual transmission of Zika has been documented in six countries – Argentina, Chile, France, Italy, New Zealand and the United States – during the 2015 outbreak.

All cases involve transmitting the Zika from men to women and it is unknown whether women can transmit Zika to their sexual partners.

Transmission During Pregnancy

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A baby born with microcephaly

In 2015, Zika RNA was detected in the amniotic fluid of two pregnant women whose fetuses had microcephaly, indicating that the virus had crossed the placenta and could have caused a mother-to-child infection.

Blood Transfusion

As of early April 2016 two cases of Zika transmission through blood transfusion have been reported globally, both from Brazil.

Risk Assessment for Africa

The WHO said though no systematic surveillance has been in place for tracking Zika virus in Africa, sporadic cases have been reported on the continent for many years. The agency added that the virus may be endemic in many parts of the continent where Aedes aegypti, the main vector of the disease, is prevalent.

Though it’s possible that some portion of the African population may have some immunity, the strain spreading rapidly in the Americas may not be known to African populations and could lead to a more acute disease, the WHO warned. “Vigilance must also be maintained.”

In the current outbreak, Cape Verde is the only African nation to report cases, more than 7,000 of them from October through December 2015. However, the WHO said that, based on available data, the number of cases has been declining since December.

All countries in the African region are at risk for Zika virus transmission, because A. aegypti mosquitoes are widely distributed and transmit several arboviruses on the continent. The WHO said the mosquito has adapted to and flourishes in urban settings found in many African cities, where poor water storage and drainage conditions can increase breeding sites for the mosquitoes.

African countries vary in their access to healthcare and disease detection and management, and ones with strong health systems are likely to cope better with a Zika outbreak, according to the WHO. The agency looked at the vulnerability of 47 countries in the region based on composite measures of hazards, vulnerabilities, and lack of coping capacity.

The WHO said all of the countries are at some risk, but it added that nearly half (20) of the countries were categorized as high risk, with Comoros, Guinea-Bissau, Central African Republic, Madagascar, and South Sudan in the top five. The five countries with the lowest risk were South Africa, Namibia, Swaziland, Mauritius, and Ghana.

The agency urged countries to take actions based on its risk assessment. For example, it said high-risk countries should be prioritized for health system support and vector control investments, and lower-risk countries should receive communication and general advisory support.

World’s First Malaria Vaccine Approved

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The world’s first malaria vaccine has been approved by the European Medicines Agency (EMA), setting the stage for a final assessment by the World Health Organisation (WHO) before the drug can be accepted by countries ravaged by the disease.

GlaxoSmithKline, the pharmaceutical company behind the drug Mosquirix, announced the approval by regulators last week, indicating that the European assessors had adopted a positive scientific opinion for its use in children aged six weeks to 17 months.

The drug, also known as RTS,S, was co-developed with the PATH Malaria Vaccine Initiative, and prevents malaria caused by the Plasmodium alciparum parasite. Global anticipation for the vaccine is immense, with despairing statistics highlighting how much of a problem malaria still is in the developing world.

Figures from 2013 indicate that the disease claims a child every single minute, with an estimated overall death toll that year of 584,000 people. The disease is prevalent in tropical and subtropical regions, with sub-Saharan Africa as the worst affected area: of the 584,000 deaths in 2013, 90 percent occurred in the region, with 83 percent in children under the age of five.

“Today’s scientific opinion represents a further important step towards making available for young children the world’s first malaria vaccine,” said Sir Andrew Witty, CEO of GlaxoSmithKline, in a statement. “While RTS,S on its own is not the complete answer to malaria, its use alongside those interventions currently available such as bed nets and insecticides, would provide a very meaningful contribution to controlling the impact of malaria on children in those African communities that need it the most.”

Having been approved by the EMA, the drug will now be reviewed by independent advisory groups on behalf of the WHO, to devise recommendations on how it could be used alongside other medicines to help prevent the disease in countries where it is approved for use by national regulators. It’s believed that the WHO’s recommendations may be announced this yeavr, but the national processes involving specific sub-Saharan countries will take additional time to be resolved. It’s hoped the vaccine will become available within the next few years.

Source: Science Alert

What Drug is Best for Preventing Malaria in Pregnancy

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A Mosquito

Pregnant women and their unborn children are particularly vulnerable to maleria: the women because they may develop lethal anaemia, and the babies because infected red blood cells tend to clump in the placenta, robbing the fetus of nutrients.

In Africa, about 30 million women a year become pregnant in areas where falciparum malaria — the most dangerous kind — is common.

To protect them, health agencies use “intermittent preventive treatment,” or I.P.T., under which all pregnant women in such areas are given doses of anti-malarial drugs at regular intervals, whether or not they are tested for the disease.

But malaria fighters sharply disagree over how to do it, and a recently published by The New England Journal of Medicine adds fuel to the debate.

To cure malaria, virtually everyone in the field uses two-drug cocktails containing, a derivative of the sweet wormwood plant.

But for preventing malaria in pregnant women, the World Health Organization recommends only an older drug combination,  Sulfadoxine-pyrimethamime— also known as Fansidar — even though resistance to it is spreading in Africa.

The new study, led by scientists from Uganda and the University of California, San Francisco, found that women who received sulfadoxine-pyrimethamine for prevention were much more likely to develop malaria symptoms during pregnancy and to have parasites in the placenta when their babies were born.

A similar study done in Kenya and published in The Lancet in 2015 had similar results.

Some experts believe the W.H.O. should change its recommendation. “To me, it’s shocking that it’s taking so long,” said Dr. Grant Dorsey, who researches malaria at U.C.S.F. and is an author of the Uganda study.

Other malaria-fighting groups are not endorsing change.

The old method is imperfect but still usually prevents deaths, said Dr. Estrella Lasry, a tropical medicine adviser at Doctors Without Borders. Using artemisinin for prevention could speed the emergence of parasites resistant to it.

“We need artemesinin for treatment, so we don’t want to burn it out,” she said.

The President’s Malaria Initiative, the American government’s global malaria-fighting program, which has paid for 42 million doses of I.P.T. since 2005, still thinks the old method protects fetuses well enough to justify continued use, a spokesman said.

The exception is in a small region of East Africa, where the initiative is backing a trial of new methods.

Source: New York Times