India, world’s last DDT maker, heaviest user, plans to stop

August 29, 2015

DDT sprayed in a vegetable market in India. (Photo: rzadigi) Living on Earth image

DDT sprayed in a vegetable market in India. (Photo: rzadigi) Living on Earth image

Sometimes big news sneaks up on us, without press releases. We often miss it.

Quiet little Tweet from journalist I’d never heard of, who passed along news from an obscure journal:

As a journalist, this guy has a piece of a world-wide scoop.

India is probably the last nation on Earth producing DDT.  In the last decade other two nations making the stuff got out of the business — North Korea and China. For several years now India has been the largest manufacturer of DDT, and far and away the greatest user, spraying more DDT against malaria-carrying mosquitoes, sand flies, and agricultural and household pests than the rest of the world combined.

As if an omen, India’s malaria rates did not drop, but instead rose, even as malaria rates dropped or plunged in almost every other nation on Earth.

Under the 2001 Stockholm Convention on Persistent Organic Pollutants (POPs) signed by more than 150 nations (not including the U.S.), DDT was one of a dozen chemicals targeted to be phased out due to its extremely dangerous qualities, including long-term persistence in the environment and bioaccummulation, by which doses of the stuff increase up the food chain, delivering crippling and fatal doses to top predators.

A perfect substitute for DDT in fighting some disease-carrying insects (“vectors”) has never been developed. Health officials asked, and the Stockholm negotiators agreed to leave DDT legally available to fight disease. Annex B asked nations to tell the World Health Organization if it wanted to use DDT. Since 2001, as DDT effectiveness was increasingly compromised by resistance evolved in insects, fewer and fewer nations found it useful.

The site Mr. Nazakat linked to is up and down, and my security program occasionally says the site is untrustworthy. It’s obscure at best. Shouldn’t news of this type be in some of India’s biggest newspapers?

I found an article in the Deccan Herald, confirming the report, but again with some

India-United Nations pact to end DDT use by 2020

India-United Nations pact to end DDT use by 2020

New Delhi, August 26, 2015, DHNS:

It would be better to switch to another insecticide, says expert

 

India is the lone user of DDT, though only in the malaria control programme, while rest of the world got rid of the chemical that has a lasting adverse impact on the environment. DH file photo

India is the lone user of DDT, though only in the malaria control programme, while rest of the world got rid of the chemical that has a lasting adverse impact on the environment. DH file photo

India has launched a $53 million project to phase out DDT by 2020 and replace them with Neem-based bio-pesticides that are equally effective.

India is the lone user of DDT, though only in the malaria control programme, while rest of the world got rid of the chemical that has a lasting adverse impact on the environment.

India on Tuesday entered into a $53 million (Rs 350 crore) partnership with the United Nations Industrial Development Organisation (UNIDO), United Nations Environment Programme and the Global Environment Facility to replace DDT with safer, more effective and green alternatives.

“As per the plan, the National Botanical Research Organisation, Lucknow, tied up with a company to produce Neem-based alternatives for the malaria programme. The production will start in six months,” Shakti Dhua, the regional coordinator of UNIDO told Deccan Herald.

Till last year, the annual DDT requirement was about 6,000 tonnes that has now been cut down to 4,000 tonnes as the government decided to stop using it in the Kala-Azar control programme.

A recent study by an Indo-British team of medical researchers found that using DDT without any surveillance is counter-productive as a vector control strategy as sand flies not only thrive but are also becoming resistant to DDT.

“It would be better to switch to another insecticide, which is more likely to give better results than DDT,” said Janet Hemingway, a scientist at the Liverpool School of Tropical Medicine. While the Health Ministry wanted to bring in synthetic pyrethroids, the United Nation agencies supports the bio-pesticides because of their efficacy and long-lasting effects.

“The new initiative would help check the spread of malaria and other vector-borne diseases. These include botanical pesticides, including Neem-based compounds, and long-lasting insecticidal safety nets that will prevent mosquito bites while sleeping,” Dhua said.

Ending the production and use of DDT is a priority for India as it is a signatory to the Stockholm Convention on Persistent Organic Pollutants (POP) of 2002 that seeks to eliminate the use of these chemicals in industrial processes, drugs and pesticides. DDT is one of the POPs.

The clock is counting down the last years of DDT.  Good.

If events unroll as planned, DDT making will end by 2020, 81 years after it was discovered to kill bugs, 70 years after it was released for civilian years, 70 years after problems with its use was first reported by the U.S. Fish and Wildlife Service, 58 years after the publication of Rachel Carson’s Silent Spring, 50 years after European nations banned some uses, 48 years after the famous U.S. ban on agricultural use, 19 years after the POPs Treaty.

When will the news leak out?

More:


Malaria No More notes milestone: Malaria at all time low

August 20, 2015

Remarkable progress against malaria marks the 21st century — but there was even more progress between 1960 and 2000. This progress usually is not noted in screeds against the World Health Organization (WHO), or Rachel Carson, or “crazy environmentalists.”

Through the 1950s, WHO estimated malaria deaths worldwide at about 5 million people each year. In about a decade of WHO’s malaria eradication campaign in temperate zones, the toll is estimated to have dropped to about 4 million dead each year.  WHO suspended the eradication campaign in 1963 when it was discovered that mosquitoes in central Africa were already resistant and immune to DDT, which was the chief pesticide used for Indoor Residual Spraying to temporarily knock down local mosquito populations. WHO tried to find substitutes for DDT, but by 1969 formally ended the program and stopped asking for money for eradication.

The fight against malaria continued, however. In 1972 the U.S. flooded malaria-prone nations with DDT which had been intended for use on U.S. crops, after the U.S. prohibited DDT on U.S. crops. For a dozen years all U.S. DDT production got channeled into Africa and Asia to fight disease.  U.S. makers had gotten out of DDT production by 1985 as production shifted to other nations.

Despite DDT’s failure, progress was made in medical care and especially in education on how to prevent mosquito bites.  The death toll dropped toward 1 million annually until about 1990. In the late 1980s, the medicines used to cure humans from malaria parasites failed, as the parasites developed their own resistance to the drugs. Through the 1990s, malaria deaths remained constant, or even rose.

A flood of concern in the late 1990s produced a coalition of malaria fighters with funding through the United Nations and non-governmental organizations (NGOs) such as the Gates Foundation and Wellcome Trust. In 1999, most of these groups agreed to fight harder, using “integrated vector management,” a variety of methods calculated to prevent mosquitoes from developing resistance to new pesticides, and prevent the malaria parasites from developing resistance to pharmaceuticals.

Plus, in nations where houses often were leaky to mosquitoes, these agencies provided bednets to prevent bites of malaria-carriers at peak biting periods, when people slept. By 2008, deaths dropped below a million each year for the first time, and progress has continued.

Beating malaria is a top goal of the United Nations’ Millennium Development Goals (MDGs); Malaria No More reported on a recently-completed report on those goals, which noted the progress against malaria.

Here is the press release from Malaria No More.

Malaria Deaths Reach All Time Low, U.N. Secretary General’s Final MDG Report Shows

NEW YORK, NY – July 6, 2015 – Malaria deaths have reached an all-time low and 6.2 million lives have been saved from the disease between 2000-2015, according to a new United Nations report announced by U.N. Secretary-General Ban Ki-moon’s office today. The final report on progress of the Millennium Development Goals (MDGs), which are set to expire this year, highlights an historic 69 percent decline in the rate of child deaths from malaria in Africa.

The report provides an update to all eight MDG Goals. The unprecedented global leadership over the past ten years to combat malaria has not only surpassed the disease-specific MDG target (Goal 6, Combat HIV/AIDS, Malaria and Other Diseases), but those efforts also contributed to critical progress toward achieving Goals 4 (Reduce Child Mortality) and 5 (Improve Maternal Health).

“Malaria is one of the standout successes of the MDGs thanks to continuous innovation, bold endemic country leadership and steadfast donor commitment,” said Ray Chambers, the U.N. Secretary-General’s Special Envoy for Malaria and Financing the Health MDGs. “We need to build on this success to ensure no child, woman or man dies from a mosquito bite and that we ultimately eradicate this disease.”

Thanks to the leadership of the United States, the Global Fund to Fight AIDS, Tuberculosis and Malaria and other international donors, malaria financing has grown dramatically from 2000-2015 to more than $3 billion annually, and political leadership has fueled the delivery of more than 1 billion mosquito nets to Africa along with hundreds of millions of effective tests and treatments.

Although these results have successfully surpassed the MDG target, the fight against malaria is not finished. Malaria remains a major global health security challenge with an estimated 3.3 billion people at risk globally. Thanks to recent success in achieving real and measureable progress, coupled with steadfast political leadership and a promising pipeline of transformative new technologies, malaria-affected regions have set ambitious goals for elimination including transformative 2020 targets in Southern Africa, Southeast Asia and the Caribbean.

“Malaria is one of the oldest and deadliest diseases in human history,” said Martin Edlund, CEO of Malaria No More. “For the first time in history we have the opportunity to capitalize on our success and end malaria within a generation; we can’t afford to miss that opportunity.”

Click here to download the full report.

Chart from USNews.com:

Estimated change in malaria incidence rate (cases per 1,000 population at risk) and malaria mortality rate (deaths per 100,000 persons at risk), 2000-2015. USNews.com chart, based on MDG report.

Estimated change in malaria incidence rate (cases per 1,000 population at risk) and malaria mortality rate (deaths per 100,000 persons at risk), 2000-2015. USNews.com chart, based on MDG report.


Malaria Twitterstorm, summer of 2015

August 18, 2015

Several good developments in the War on Malaria, worldwide — along with some alarming signs.  Maybe there will be time to blog seriously about each of these things later. Let’s get them known, and keep discussion going for the best way to beat malaria in a post-DDT world.

QPharm Tweeted about DSM 265, an experimental, one-dose treatment developed by the Medicines for Malaria Venture (MMV); the video is useful for the background those new to the issue can get on the problems of treating malaria, which make great hurdles for campaigns to eradicate malaria.

Here’s the video the Tweet leads to.

MMV said:

DSM265 is a selective inhibitor of the plasmodial enzyme called DHODH. DHODH is a key enzyme in the replication of the parasite. If we can inhibit that enzyme with DSM265, we can stop the life of the parasite.

Voice of America reported on Rollback Malaria’s call for $100 billion to be spent in the next 15 years, to stamp out the disease.

Malaria deaths are, in 2015, at an “all time low.” Deaths hover around 500,000 per year, most in Africa, and most among children under the age of 5. A staggering total, until compared to the post-World War II estimates of more than 5 million deaths per year, or the more than 3 million deaths per year in 1963, the year the World Health Organization (WHO) had to stop its ambitious campaign to eradicate malaria when pesticide DDT, upon which the campaign was based, produced resistance in mosquitoes in areas where the campaign had not yet reached.

Beating malaria is one of the Millennium Development Goals of the United Nations; this year’s report on MDG acknowledged the great progress already made.

Another non-governmental malaria-fighting organization discussed the news; see the press release from Malaria No More.

Medical News Today Tweeted out a tout for its own coverage of malaria — notable for a good, basic explanation of malaria and how to fight it.  I wish critics of Rachel Carson and WHO were familiar with half of these basic facts.

Medical News Now's Fast Facts on Malaria

Medical News Now’s Fast Facts on Malaria. Notable, that annual deaths now are way below the million mark. Good news!

One malaria vaccine has won approval for final testing. Good news, though anyone who follows vaccines knows it will take a while to test, and anyone who knows malaria fighting knows there are four different parasites, and delivery of any medical care is tough in far too many parts of the world where any form of malaria is endemic. Even small good news is good news.

Are we better informed about malaria now? Do we understand spreading a lot more DDT is not the answer?

 


Wellcome Trust interactive on malaria parasites’ lifecycle

August 12, 2015

Screen capture of the Wellcome Trust HTML presentation on the life cycle of malaria parasites. Malaria fighters know all this almost instinctively; too often policy makers fail to understand it, and so they recommend policies that do not make medical or economic sense in fighting the disease. Click image to go to Wellcome Trust site for full presentation.

Screen capture of the Wellcome Trust HTML presentation on the life cycle of malaria parasites. Malaria fighters know all this almost instinctively; too often policy makers fail to understand it, and so they recommend policies that do not make medical or economic sense in fighting the disease. Click image to go to Wellcome Trust site for full presentation.

Britain’s Wellcome Trust takes as one of its key missions the fight against malaria.  The Trust is a charitable foundation created from profits of pharmaceutical development and sales.

Recently I found this HTML animation presentation on the life cycle of the malaria parasite, something all malaria fighters must know to be effective.

It’s also something that DDT advocates seem unable to comprehend.  Malaria is not a virus, nor is it a venom mosquitoes manufacture, but it is a parasite that infects (and disables) both mosquitoes and humans. Mosquitoes catch the parasite from an infected human host. After the malaria parasite completes a couple of cycles in the gut of the mosquito, the parasite can be transmitted back to humans by a mosquito bite. And the cycle continues.

Since complete eradication of malaria-carrying mosquitoes is practically impossible in almost all cases, beating malaria requires an interruption in the cycle of transmission of the parasite, plus the curing of the disease in infected human hosts.

For example, the old World Health Organization (WHO) malaria eradication campaign, which operated from 1955 to 1963, DDT was used to temporarily knock down a population of mosquitoes, with hopes human hosts would be ridded of malaria parasites so that, in six months or so, when the mosquito populations roared back, there would be no malaria in local humans to infect mosquitoes. Consequently, mosquitoes can’t transmit a parasite they don’t have.

Lost on far too many people: Humans must be cured of malaria to prevent transmission. Beating malaria takes a lot more than just killing mosquitoes.

Check out the interactive:  Malaria parasite life cycle

While you’re there, snoop around to see what else Wellcome Trust is up to in the malaria fight.

 


Key part of Burwell decision: “Congress passed the Affordable Care Act to improve health insurance markets”

June 25, 2015

U.S. Supreme Court hearing oral arguments in King v. Burwell.  The decision issued on June 25, 2015. Image from Newsworks (who is the artist?)

U.S. Supreme Court hearing oral arguments in King v. Burwell. The decision issued on June 25, 2015. Image from Newsworks. [Continued search for credit information on this image turned up this caption; artist is Dana Verkouteren of Associated Press] “This courtroom artist rendering shows Michael Carvin, lead attorney for the petitioners, right, speaking before the Supreme Court in March. King v. Burwell, a major test of the Affordable Care Act, could halt health care premium subsidies in all the states where the federal government runs the insurance marketplaces. (AP Photo/Dana Verkouteren)

In all the rending of garments and gnashing of teeth about the Supreme Court’s decision in the Burwell case today, you’d be lucky to learn what the Court actually said.

Here are the key paragraphs of the majority’s decision (links added here), as written by Chief Justice John Roberts:

Reliance on context and structure in statutory interpretation is a “subtle business, calling for great wariness lest what professes to be mere rendering becomes creation and attempted interpretation of legislation becomes legislation itself.” Palmer v. Massachusetts, 308 U. S. 79, 83 (1939). For the reasons we have given, however, such reliance is appropriate in this case, and leads us to conclude that Section 36B allows tax credits for insurance purchased on any Exchange created under the Act. Those credits are necessary for the Federal Exchanges to function like their State Exchange counterparts, and to avoid the type of calamitous result that Congress plainly meant to avoid.

*    *    *

In a democracy, the power to make the law rests with those chosen by the people. Our role is more confined—“to say what the law is.” Marbury v. Madison, 1 Cranch 137, 177 (1803). That is easier in some cases than in others. But in every case we must respect the role of the Legislature, and take care not to undo what it has done. A fair reading of legislation demands a fair understanding of the legislative plan.

Congress passed the Affordable Care Act to improve health insurance markets, not to destroy them. If at all possible, we must interpret the Act in a way that is consistent with the former, and avoids the latter. Section 36B can fairly be read consistent with what we see as Congress’s plan, and that is the reading we adopt.

The judgment of the United States Court of Appeals for the Fourth Circuit is

Affirmed.

Go read the rest of the 47 pages (in the .pdf from the Supreme Court), if you wish to be well-informed.  The case probably isn’t at all what’s being reported in most venues.


One billion nets to Africa

May 21, 2015

Malaria No More reports a billion mosquito nets in Africa produce great results in the fight against malaria.

Malaria No More reports a billion mosquito nets in Africa produce great results in the fight against malaria.

Interesting week.

All that, and the World Health Assembly 68 is meeting in Geneva, Switzerland.  Among top items on the agenda of the world’s top public health experts: What are the next steps in fighting malaria?

Malaria No More produced this short video in time for World Malaria Day, April 25, 2015 — but I just saw it this week.  It depicts the Ochieng family in Kenya, and the effects of malaria, and beating malaria, have on the family:

One Billion Nets to Africa

Description of the film:

Meet the Ochieng family. They are one of the families that received the #OneBillionNets to Africa and is now protected from malaria-transmitting mosquitoes because of this unprecedented global effort. See more at 1BillionNets.org

  • Music:  “Eyes Wide Open” by Tony Anderson

This film caught my interest on a personal scale.  One of my great students at Molina High School in Dallas was a Kenyan immigrant, named Ochieng.  Can’t help but wonder if there is a relation.

Bednets, and a concentrated, international campaign to prevent mosquito bites and cure infected humans of the disease, have cut malaria deaths from just over 1 million per year in 2000, to fewer than 600,000 per year in 2014.  This progress produces hope again that malaria can be beaten, though there are many more hurdles blocking the path.

You may have noted: The malaria fighters at Malaria No More make no plea for more DDT, nor do they claim any handicap from the U.S. having banned the use of DDT on agricultural crops in the U.S.  In saving lives, disease fighters don’t have time to deal with destructive hoaxes.

Tip of the old scrub brush to PMI, the President’s Malaria Initiative:
http://twitter.com/PMIgov/status/596689144618823680


WHO’s malaria fact sheet, April 2015 edition

May 17, 2015

Progress against the diseases we know as malaria — parasitic infections — is dramatic and rapid since several non-governmental organizations (NGOs) entered the fight seriously at the turn of the last century. But problems arise and also rapidly become serious.

Bednets prove the best single method of preventing the spread of malaria. Distribution of bednets in malaria-prone regions greatly aided the 47% reduction in malaria deaths since 1999.  WHO photo.

Bednets prove the best single method of preventing the spread of malaria. Distribution of bednets in malaria-prone regions greatly aided the 47% reduction in malaria deaths since 1999. WHO photo.

For political reasons often obscure, there is an industry in creating misinformation and propaganda against malaria-fighting groups like the World Health Organization, the Bill and Melinda Gates Foundation, and other groups who advocate bednet preventive measures. The propagandists often make absurd and false claims against medical workers, against scientists and activists including people they pejoratively call environmentalists, and in favor of the deadly poison DDT.

Factual matter takes longer to spread — truth has a smaller public relations budget.

What are the facts about malaria?

Here is WHO’s fact sheet on malaria, current as of the first of this month 2015.

WHO’s fact sheet is almost dull in its recitation of the facts.  What you don’t see recorded here is that the death toll of over 500,000 last year, is the lowest death toll from malaria since World War II, the lowest death toll estimated in the past 120 years, and perhaps the lowest death toll in recorded human history.  Similarly, while nearly 200 million malaria infections seems an enormous number, that number records a dramatic reduction from the 500 million estimated in the 1960s.

Malaria is not Rachel Carson’s fault. DDT is not a magic cure for the disease. It’s beatable, but beating a disease requires constant vigilance, militant prevention and treatment — and that costs money. The propagandists won’t tell you those facts, and malaria wins when bad information chases out the good.

For the record:

Malaria

Fact sheet N°94
Reviewed April 2015


Key facts

  • Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected mosquitoes.
  • In 2013, malaria caused an estimated 584 000 deaths (with an uncertainty range of 367 000 to 755 000), mostly among African children.
  • Malaria is preventable and curable.
  • Increased malaria prevention and control measures are dramatically reducing the malaria burden in many places.
  • Non-immune travellers from malaria-free areas are very vulnerable to the disease when they get infected.

According to the latest estimates, released in December 2014, there were about 198 million cases of malaria in 2013 (with an uncertainty range of 124 million to 283 million) and an estimated 584 000 deaths (with an uncertainty range of 367 000 to 755 000). Malaria mortality rates have fallen by 47% globally since 2000, and by 54% in the WHO African Region.

Most deaths occur among children living in Africa where a child dies every minute from malaria. Malaria mortality rates among children in Africa have been reduced by an estimated 58% since 2000.

Malaria is caused by Plasmodium parasites. The parasites are spread to people through the bites of infected Anopheles mosquitoes, called “malaria vectors”, which bite mainly between dusk and dawn.

There are four parasite species that cause malaria in humans:

  • Plasmodium falciparum
  • Plasmodium vivax
  • Plasmodium malariae
  • Plasmodium ovale.

Plasmodium falciparum and Plasmodium vivax are the most common. Plasmodium falciparum is the most deadly.

In recent years, some human cases of malaria have also occurred with Plasmodium knowlesi – a species that causes malaria among monkeys and occurs in certain forested areas of South-East Asia.

Transmission

Malaria is transmitted exclusively through the bites of Anopheles mosquitoes. The intensity of transmission depends on factors related to the parasite, the vector, the human host, and the environment.

About 20 different Anopheles species are locally important around the world. All of the important vector species bite at night. Anopheles mosquitoes breed in water and each species has its own breeding preference; for example some prefer shallow collections of fresh water, such as puddles, rice fields, and hoof prints. Transmission is more intense in places where the mosquito lifespan is longer (so that the parasite has time to complete its development inside the mosquito) and where it prefers to bite humans rather than other animals. For example, the long lifespan and strong human-biting habit of the African vector species is the main reason why about 90% of the world’s malaria deaths are in Africa.

Transmission also depends on climatic conditions that may affect the number and survival of mosquitoes, such as rainfall patterns, temperature and humidity. In many places, transmission is seasonal, with the peak during and just after the rainy season. Malaria epidemics can occur when climate and other conditions suddenly favour transmission in areas where people have little or no immunity to malaria. They can also occur when people with low immunity move into areas with intense malaria transmission, for instance to find work, or as refugees.

Human immunity is another important factor, especially among adults in areas of moderate or intense transmission conditions. Partial immunity is developed over years of exposure, and while it never provides complete protection, it does reduce the risk that malaria infection will cause severe disease. For this reason, most malaria deaths in Africa occur in young children, whereas in areas with less transmission and low immunity, all age groups are at risk.

Symptoms

Malaria is an acute febrile illness. In a non-immune individual, symptoms appear seven days or more (usually 10–15 days) after the infective mosquito bite. The first symptoms – fever, headache, chills and vomiting – may be mild and difficult to recognize as malaria. If not treated within 24 hours, P. falciparum malaria can progress to severe illness often leading to death. Children with severe malaria frequently develop one or more of the following symptoms: severe anaemia, respiratory distress in relation to metabolic acidosis, or cerebral malaria. In adults, multi-organ involvement is also frequent. In malaria endemic areas, persons may develop partial immunity, allowing asymptomatic infections to occur.

For both P. vivax and P. ovale, clinical relapses may occur weeks to months after the first infection, even if the patient has left the malarious area. These new episodes arise from dormant liver forms known as hypnozoites (absent in P. falciparum and P. malariae); special treatment – targeted at these liver stages – is required for a complete cure.

Who is at risk?

Approximately half of the world’s population is at risk of malaria. Most malaria cases and deaths occur in sub-Saharan Africa. However, Asia, Latin America, and to a lesser extent the Middle East and parts of Europe are also affected. In 2014, 97 countries and territories had ongoing malaria transmission.

Specific population risk groups include:

  • young children in stable transmission areas who have not yet developed protective immunity against the most severe forms of the disease;
  • non-immune pregnant women as malaria causes high rates of miscarriage and can lead to maternal death;
  • semi-immune pregnant women in areas of high transmission. Malaria can result in miscarriage and low birth weight, especially during first and second pregnancies;
  • semi-immune HIV-infected pregnant women in stable transmission areas, during all pregnancies. Women with malaria infection of the placenta also have a higher risk of passing HIV infection to their newborns;
  • people with HIV/AIDS;
  • international travellers from non-endemic areas because they lack immunity;
  • immigrants from endemic areas and their children living in non-endemic areas and returning to their home countries to visit friends and relatives are similarly at risk because of waning or absent immunity.

Diagnosis and treatment

Early diagnosis and treatment of malaria reduces disease and prevents deaths. It also contributes to reducing malaria transmission.

The best available treatment, particularly for P. falciparum malaria, is artemisinin-based combination therapy (ACT).

WHO recommends that all cases of suspected malaria be confirmed using parasite-based diagnostic testing (either microscopy or rapid diagnostic test) before administering treatment. Results of parasitological confirmation can be available in 15 minutes or less. Treatment solely on the basis of symptoms should only be considered when a parasitological diagnosis is not possible. More detailed recommendations are available in the “Guidelines for the treatment of malaria” (second edition). An updated edition will be published in 2015.

Antimalarial drug resistance

Resistance to antimalarial medicines is a recurring problem. Resistance of P. falciparum to previous generations of medicines, such as chloroquine and sulfadoxine-pyrimethamine (SP), became widespread in the 1970s and 1980s, undermining malaria control efforts and reversing gains in child survival.

In recent years, parasite resistance to artemisinins has been detected in 5 countries of the Greater Mekong subregion: Cambodia, Laos, Myanmar, Thailand and Viet Nam. While there are likely many factors that contribute to the emergence and spread of resistance, the use of oral artemisinins alone, as monotherapy, is thought to be an important driver. When treated with an oral artemisinin-based monotherapy, patients may discontinue treatment prematurely following the rapid disappearance of malaria symptoms. This results in incomplete treatment, and such patients still have persistent parasites in their blood. Without a second drug given as part of a combination (as is provided with an ACT), these resistant parasites survive and can be passed on to a mosquito and then another person.

If resistance to artemisinins develops and spreads to other large geographical areas, the public health consequences could be dire.

WHO recommends the routine monitoring of antimalarial drug resistance, and supports countries to strengthen their efforts in this important area of work.

More comprehensive recommendations are available in the “WHO Global Plan for Artemisinin Resistance Containment (GPARC)”, which was released in 2011. For countries in the Greater Mekong subregion, WHO has issued a regional framework for action titled “Emergency response to artemisinin resistance in the Greater Mekong subregion” in 2013.

Prevention

Vector control is the main way to reduce malaria transmission at the community level. It is the only intervention that can reduce malaria transmission from very high levels to close to zero.

For individuals, personal protection against mosquito bites represents the first line of defence for malaria prevention.

Two forms of vector control are effective in a wide range of circumstances.

Insecticide-treated mosquito nets (ITNs)

Long-lasting insecticidal nets (LLINs) are the preferred form of ITNs for public health distribution programmes. WHO recommends coverage for all at-risk persons; and in most settings. The most cost effective way to achieve this is through provision of free LLINs, so that everyone sleeps under a LLIN every night.

Indoor spraying with residual insecticides

Indoor residual spraying (IRS) with insecticides is a powerful way to rapidly reduce malaria transmission. Its full potential is realized when at least 80% of houses in targeted areas are sprayed. Indoor spraying is effective for 3–6 months, depending on the insecticide used and the type of surface on which it is sprayed. DDT can be effective for 9–12 months in some cases. Longer-lasting forms of existing IRS insecticides, as well as new classes of insecticides for use in IRS programmes, are under development.

Antimalarial medicines can also be used to prevent malaria. For travellers, malaria can be prevented through chemoprophylaxis, which suppresses the blood stage of malaria infections, thereby preventing malaria disease. In addition, WHO recommends intermittent preventive treatment with sulfadoxine-pyrimethamine for pregnant women living in high transmission areas, at each scheduled antenatal visit after the first trimester. Similarly, for infants living in high-transmission areas of Africa, 3 doses of intermittent preventive treatment with sulfadoxine-pyrimethamine is recommended delivered alongside routine vaccinations. In 2012, WHO recommended Seasonal Malaria Chemoprevention as an additional malaria prevention strategy for areas of the Sahel sub-Region of Africa. The strategy involves the administration of monthly courses of amodiaquine plus sulfadoxine-pyrimethamine to all children under 5 years of age during the high transmission season.

Insecticide resistance

Much of the success to date in controlling malaria is due to vector control. Vector control is highly dependent on the use of pyrethroids, which are the only class of insecticides currently recommended for ITNs or LLINs. In recent years, mosquito resistance to pyrethroids has emerged in many countries. In some areas, resistance to all 4 classes of insecticides used for public health has been detected. Fortunately, this resistance has only rarely been associated with decreased efficacy, and LLINs and IRS remain highly effective tools in almost all settings.

However, countries in sub-Saharan Africa and India are of significant concern. These countries are characterized by high levels of malaria transmission and widespread reports of insecticide resistance. The development of new, alternative insecticides is a high priority and several promising products are in the pipeline. Development of new insecticides for use on bed nets is a particular priority.

Detection of insecticide resistance should be an essential component of all national malaria control efforts to ensure that the most effective vector control methods are being used. The choice of insecticide for IRS should always be informed by recent, local data on the susceptibility target vectors.

In order to ensure a timely and coordinated global response to the threat of insecticide resistance, WHO has worked with a wide range of stakeholders to develop the “Global Plan for Insecticide Resistance Management in malaria vectors” (GPIRM), which was released in May 2012. The GPIRM puts forward a five-pillar strategy calling on the global malaria community to:

  • plan and implement insecticide resistance management strategies in malaria-endemic countries;
  • ensure proper and timely entomological and resistance monitoring, and effective data management;
  • develop new and innovative vector control tools;
  • fill gaps in knowledge on mechanisms of insecticide resistance and the impact of current insecticide resistance management approaches; and
  • ensure that enabling mechanisms (advocacy as well as human and financial resources) are in place.

Surveillance

Tracking progress is a major challenge in malaria control. In 2012, malaria surveillance systems detected only around 14% of the estimated global number of cases. Stronger malaria surveillance systems are urgently needed to enable a timely and effective malaria response in endemic regions, to prevent outbreaks and resurgences, to track progress, and to hold governments and the global malaria community accountable.

Elimination

Malaria elimination is defined as interrupting local mosquito-borne malaria transmission in a defined geographical area, i.e. zero incidence of locally contracted cases. Malaria eradication is defined as the permanent reduction to zero of the worldwide incidence of malaria infection caused by a specific agent; i.e. applies to a particular malaria parasite species.

On the basis of reported cases for 2013, 55 countries are on track to reduce their malaria case incidence rates by 75%, in line with World Health Assembly targets for 2015. Large-scale use of WHO-recommended strategies, currently available tools, strong national commitments, and coordinated efforts with partners, will enable more countries – particularly those where malaria transmission is low and unstable – to reduce their disease burden and progress towards elimination.

In recent years, 4 countries have been certified by the WHO Director-General as having eliminated malaria: United Arab Emirates (2007), Morocco (2010), Turkmenistan (2010), and Armenia (2011).

Vaccines against malaria

There are currently no licensed vaccines against malaria or any other human parasite. One research vaccine against P. falciparum, known as RTS, S/AS01, is most advanced. This vaccine has been evaluated in a large clinical trial in 7 countries in Africa and has been submitted to the European Medicines Agency under art. 58 for regulatory review. A WHO recommendation for use will depend on the final results from the large clinical trial and a positive regulatory review. The recommendation as to whether or not this vaccine should be added to existing malaria control tools is expected in late 2015.

WHO response

The WHO Global Malaria Programme (GMP) is responsible for charting the course for malaria control and elimination through:

  • setting, communicating and promoting the adoption of evidence-based norms, standards, policies, technical strategies, and guidelines;
  • keeping independent score of global progress;
  • developing approaches for capacity building, systems strengthening, and surveillance;
  • identifying threats to malaria control and elimination as well as new areas for action.

GMP serves as the secretariat for the Malaria Policy Advisory Committee (MPAC), a group of 15 global malaria experts appointed following an open nomination process. The MPAC, which meets twice yearly, provides independent advice to WHO to develop policy recommendations for the control and elimination of malaria. The mandate of MPAC is to provide strategic advice and technical input, and extends to all aspects of malaria control and elimination, as part of a transparent, responsive and credible policy setting process.

WHO is also a co-founder and host of the Roll Back Malaria partnership, which is the global framework to implement coordinated action against malaria. The partnership mobilizes for action and resources and forges consensus among partners. It is comprised of over 500 partners, including malaria endemic countries, development partners, the private sector, nongovernmental and community-based organizations, foundations, and research and academic institutions.

For more information contact:

WHO Media centre
Telephone: +41 22 791 2222
E-mail: mediainquiries@who.int

WHO provides a short video summary of many of these facts.


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