India, world’s top DDT user, socked with malaria increase

July 22, 2015

Were it true that DDT is a magic solution to malaria, by all measures India should be malaria free.

Not only is India not malaria-free, but the disease increases in infections, deaths, and perhaps, in virulence.

Map showing location of Odisha, or Orissa, state, in India. Wikipedia image

Map showing location of Odisha, or Orissa, state, in India. Wikipedia image

Since the late 1990s a small, well-funded band of chemical and tobacco industry propagandists conducted a campaign of calumny against Rachel Carson, environmentalists in general, scientists and health care workers, claiming that an unholy and wrongly-informed conspiracy took DDT off the market just as great strides were beginning to be made against malaria.

As a consequence, this group argues, malaria infections and deaths exploded, and tens of millions of people died unnecessarily.

That’s a crock, to be sure. Rachel Carson’s 1962 book, Silent Spring, inspired an already-established campaign against DDT. But the malaria eradication program begun with high hopes by the World Health Organization in 1955, foundered in 1963 when the campaign turned to central, tropical Africa. Overuse of DDT in agriculture and minor pest control had bred DDT-resistant and immune mosquitoes.  Malaria fighters could not knock down local populations of mosquitoes well enough to let medical care cure infected humans.  (The campaign was not helped by political instability in some of the African nations; 80% of houses in an affected area need to be sprayed inside to stop malaria, and that requires government organizational skills, manpower and money that those nations could not muster.)

Detail map of Odisha state, India; map by Jayanta Nath, Wikipedia image

Detail map of Odisha state, India; map by Jayanta Nath, Wikipedia image

That was just a year after Carson’s book hit the shelves. DDT had been banned nowhere. WHO’s workers tried to get a campaign going, but complete failures stopped the program in 1965; in 1969 WHO’s board met and officially killed the malaria eradication program, in favor of control.

Malaria infections and deaths did not expand with the end of WHO’s campaign.  At peak DDT use, roughly 1958 to 1963, malaria deaths are estimated by WHO to have been as high as 5 million per year, 4 million by 1963. Total malaria infections, worldwide, were 500 million.

The first bans on DDT use came in Europe. When the U.S. banned DDT use on crops in 1972, okaying use to fight malaria, malaria deaths had fallen to more than 2 million annually by optimistic estimates.  Death rates and infection rates continued to fall without a formal eradication campaign. By the late 1980s, malaria killed about 1.5 million each year, a great improvement over the DDT go-go days, but still troubling.

Beating malaria is a multi-step program.  Malaria parasites must complete a life cycle in a human host, and then when jumping to a mosquito, another cycle of about two weeks in the mosquito’s gut, before being transmissible back to humans. Knocking down mosquito populations helps prevent transmission temporarily, but that is only useful if in that period the human hosts can be cured of the parasites.

In the late 1980s, malaria parasites developed strong resistance and immunity to pharmaceuticals given to humans to cure them.  Regardless mosquito populations, human hosts were always infected, ready to transmit the parasite to any mosquito and send drug-resistant malaria on to dozens more.

From about 1990 to about 2002, malaria deaths rose modestly to more than 1.5 million annually.

New pharmaceuticals, and new regimens of administration of pharmaceuticals, increased the effectiveness of human treatments; coupled with much better understanding of malaria vectors, the insects that transmit the disease, and geographical data and other technological advances to speed diagnosis and treatment of humans, and increase prevention measures, WHO and private foundations started a series of programs in malaria-endemic nations to reduce infections and deaths. Insecticide-impregnated bednets proved to be less-expensive and more effective than Indoor Residual Spraying (IRS) featuring DDT or any of the other 11 pesticides WHO authorizes for home spraying.  (Home spraying targets mosquitoes that carry malaria, and limits expensive overuse of pesticides, plus limits and prevents environmental damage.)

Health care workers and most nations made dramatic progress in controlling and eliminating malaria, between 2000 and 2015, mostly without using DDT which proved increasingly ineffective at controlling mosquitoes, and which also proved unpopular among malaria-affected peoples whose cooperation is necessary to fight the disease.

By 2014, fewer than 220 million people got malaria infections, worldwide, a reduction of about 55% over DDT’s peak-use years. This is remarkable considering the population of the planet more than doubled in that time, and population in malaria-endemic areas rose even more. Malaria deaths were reduced to fewer than 600,000 annually, a reduction of more than 80% over peak DDT years. By 2015, malaria-fighters once again spoke of eradicating malaria from the planet.

In contrast, India assumed the position of top producer of DDT in the world, still making it even after China and North Korea stopped making it. But malaria control in India weakened, despite greater application of DDT.  The world watches as DDT, once the miracle pesticide used in anti-malaria campaigns, became instead a depleted tool, unable to stop malaria’s spread despite increasing application.

Were DDT the magic powder, or even “excellent powder” its advocates claim, India should be free of malaria, totally. Instead, Indians debate how best to get control of the disease again, and start reducing infections and deaths, again. Below is one story, rather typical of many that crop up from time to time in India news; this is from the Odisha Sun Times. (Note: Lakh is a unit in the Indian number system equal to 100,000; crore is a unit equal to 10,000,000.)

Odisha has 36% of malaria cases in India; ranks third in deaths

Odisha Sun Times Bureau
Bhubaneswar, Mar 15:

Odisha has earned the dubious distinction of having a hopping 36% share of all malaria cases in India and ranking third in the list of states with the most number of deaths leaving most of its neighbours way behind.

Malaria Mosquito

These startling revelations have been made in a report tabled by the Union Health and Family Welfare department in the Parliament.

What is more disturbing is that the number of persons getting afflicted with the disease in the state is rising every year despite the state government spending crores of rupees to arrest the spread of the disease.

The state government has been spending crores of rupees on a scheme christened ‘Mo Masari’ (“My Mosquito Net’) and has been claiming that the number of afflicted has been falling in the state. But the Central government report has exposed the hollowness of the claim.

According to the report, out of the 10.70 lakh people who were afflicted with malaria in India in the year 2014, about 3.88 lakh (36.26%) were from Odisha. In 2010, around 3.95 lakh were afflicted with the disease. The number had come down to 3.08 lakh in 2011 and had further scaled down to around 2.62 lakh in 2012, the report says.

But the number of malaria patients in Odisha is again rising at a faster pace since then, according to the Health Ministry report.

Even though the neighbouring states of Jharkhand and Chhattisgarh are identified as malaria prone states, much less people are afflicted with malaria in these states as compared to Odisha. In 2014, only 1.22lakh people were affected with the disease in Chhattisgarh while only 96,140 persons were affected by malaria in Jharkhand in the same year.

Statistics cited in the report also reveal that Odisha has left many states behind and has marched ahead of others in the matter of number of deaths due to malaria. It ranks third on this count in the country.

In the year 2014, a total of 535 persons had died of malaria across the country. Out of them 73 (13.64%) were from Odish while Tripura had the maximum number of deaths in terms of percentage at 96 (17.94%) followed by Meghalaya, another hilly state, with a toll count of 78 (14.58%).

Another disturbing fact that has emerged from the report is that out of those who have died of malaria in Odisha, 80 percent are from tribal dominated areas.

The districts of Gajapati , Kalahandi , Kandhamal, Keonjhar, Koraput, Malkangiri, Mayurbhanj, Nabarangpur, Nuapada, Rayagada and Sundargarh account for both the maximum number of deaths due to malaria and maximum number of persons afflicted with the disease.


Hoax victims afraid to discuss their misplaced DDT & malaria anger . . .

July 20, 2015

We see it almost daily — probably because we’ve got searches set to find comments on malaria and DDT.

British robin, or robin redbreast. Image found on Pinterest, and also ironically used to illustrate Pointman's screed for DDT.

British robin, or robin redbreast. Image found on Pinterest, and also ironically used to illustrate Pointman’s screed for DDT. Ironic, because Britain didn’t use as much DDT, and European robins were not so badly affected as U.S. robins. Not sure if Pointman knew that and used the photo to intentionally mislead, or if he’s just really bad at identifying species.

Some well-meaning guy (or woman) writes a long piece about conscience, and then claims to have lost respect for science, or medicine professionals, or the World Health Organization (WHO), or Rachel Carson or environmentalists, or all of them at once, because Rachel Carson’s ban on DDT meant malaria infections and deaths exploded, and libruls just won’t allow anyone to fix it.

If you’re a regular reader, you know that story is impossible, because:

The standard rant against Rachel Carson in favor of DDT is impossible in three ways:

  1. EPA’s regulation cannot travel back in time to cause an end to WHO’s malaria eradication campaign (1963) nine years before the rule was made (1972); nor can history and international law be changed to make EPA’s campaign stop the use of DDT outside the U.S.
  2. Mosquitoes do not migrate thousands of miles, across oceans. EPA’s ban on spraying U.S. crops with DDT, chiefly cotton, did not cause mosquitoes to migrate from Arkansas to Africa to spread malaria.  Had they done so, DDT in Africa had a pretty good chance to getting them, anyway.
  3. A reduction of malaria deaths from 4 million to 584,000, is not an increase in deaths.

These impossibilities do not even act as speed bumps to people in a hurry to condemn science, Rachel Carson, malaria fighters and environmentalists, in a mad rush to praise DDT, a deadly poison that doesn’t do what we hoped it would, any more.

Those undeterred from slandering Rachel Carson and environmentalists often don’t want to be informed of any errors in their rant. And so, Pointman, with a nasty false indictment of science, law and environmentalists, refuses to allow my posts to correct his errors.

His screed here.  It contains at least 6 gross errors, repeating all the impossibilities listed above, and slandering both Rachel Carson and William Ruckelshaus as “mass murderers,” with the false claim that EPA stopped DDT use against malaria.

My response, dealing with a small part of the errors, below (and here at Pointman’s blog; but in moderation, so you can’t see it, at the time of this posting).

EPA’s order banning DDT use in the U.S., on crops, specifically lifted the court-imposed ban on DDT manufacture, and specifically allowed use of DDT in the U.S. or anywhere else on Earth to fight vector-borne diseases — that is, malaria.

DDT manufacture continued in the U.S. until late 1984, when a new law made DDT manufacturers responsible for not poisoning their neighbors and neighborhoods. Most DDT manufacturing arms of larger chemical companies were spun off as separate enterprises, and they declared bankruptcy rather than assume any liability for the poisons they made for huge profits.

See description of EPA order and links to the original documents here: https://timpanogos.wordpress.com/2014/10/29/oh-look-epa-ordered-ddt-to-be-used-to-fight-malaria-in-1972/

I waited several days, and send two notices asking to spring the comment from moderation. I don’t think “Pointman” is interested in discussion.

[Update]
Further reflection, a further thought — “Pointman” probably is not interested in discussion, not because he fears it — he’s probably armed, what does he have to fear? — but because he no longer caresHe’s seen the effects of good intentions gone wrong, and if it ever occurs to him it’s not his intentions, nor his going, that might be wrong, he’ll never let on.

More:


Rachel Carson’s 108th birth anniversary

May 27, 2015

Rachel Carson, the great biologist and author, was born on May 27, 1907.

Last year, Google’s Doodle featured Ms. Carson, and the crazy, ill-informed, hoaxing and hoaxed right wing, came unglued.

Less flap this year, but I suspect it’s only because there’s been no great public recognition of the date.  Hoaxsters who insist DDT was always safe, or that banning DDT on cotton crops in Arkansas and Texas somehow caused malaria in Africa, or that Idi Amin became a great fan of Rachel Carson and stopped spraying DDT in Uganda to save American eagles, or other similarly silly-but-vicious things, or who just hate anything to do with protecting the environment, usually erupt on Earth Day, World Malaria Day, and Rachel Carson’s birthday.

Not much on her birthday this year (but stay tuned).

Meanwhile, our country’s sober liberal conscience, The Nation, looks back at their review of Silent Spring, and does a little cringing. Probably not necessary:

Rachel Carson, date unknown. (US Department of Agriculture) - via The Nation

Rachel Carson, date unknown. (US Department of Agriculture) – via The Nation

It is difficult not to cringe at the sight of the headline to the following review of Rachel Carson’s groundbreaking book, Silent Spring—“Man and Other Pests”—given that it was a review of what was then probably the most influential intellectual contribution by an American woman to date.

Miss Carson is indignant about the unexpected effects of our thoughtless broadcasting of pesticides. She writes persuasively, for she has taken great pains to gather and check her facts. Parts of the book were published in The New Yorker magazine last summer, and immediately provoked wide interest, discussion and controversy. This reaction will undoubtedly intensify with the publication of the book. No one is in a better position than Miss Carson to arouse the indignation of the public and the conscience of the chemical industry, and it may well be that she has made a real contribution to our salvation.

[At The Nation, you can read the entire review quoted from above.]

Happy birthday, Ms. Carson.  You have become a hero to thinking people, conservationists, scientists and women everywhere.

You’ll be pleased to know the American symbol, the bald eagle, is back from extinction’s verge, along with the brown pelican, peregrine falcons and osprey.  You’d be surprised to know that, despite gross abuse of DDT in the 1950s and 1960s that caused mosquitoes all over the world to carry alleles resistance and immunity, DDT was saved from complete worthlessness by a reduction in use, and is still used in a few places today, indoors to protect wildlife, to fight malaria.  You were right about DDT.

You were right about fighting malaria, too.  You said in Silent Spring we should use integrated pest management to battle the mosquitoes that provide a site for part of the life cycle of the malaria parasites, and who then spread the disease.  When DDT failed the malaria eradication campaign in the 1960s, malaria fighters were left with little else. Malaria deaths have plunged, from the 4 million to 5 million per year you knew, to fewer than 500,000 per year now.  Worldwide, we’ve cut malaria deaths 45% just since 1999, when a group of non-governmental organizations and the World Health Organization formally adopted integrated pest management as the best way to fight the disease, and began distributing mosquito nets in a big way.

You were right, Rachel Carson. Humanity is a part of nature, and if we fight nature we end up fighting and killing ourselves.

More:

One of my favorites from Gus Arriola (also appearing at the DDT Chronicles):


Highlights from the World Health Assembly #68, in graphic form

May 26, 2015

World Health Organization (WHO) summary of the World Health Assembly #68, which met in Geneva last, May 18-26.

Not a peep about “more DDT to fight malaria.’

Graphic from the World Health Organization on major actions of the World Health Assembly 68, in Geneva, Switzerland, May 18-26, 2015

Graphic from the World Health Organization on major actions of the World Health Assembly 68, in Geneva, Switzerland, May 18-26, 2015

 

 


I get e-mail: Nothing But Nets needs your help with Congress, to fight malaria

May 26, 2015

Money, not DDT.

Among other goals of the hoaxsters who claim Rachel Carson was wrong and evil, and that the imaginary ban on DDT to fight malaria causes “millions of deaths,” is the erosion of trust in international  organizations that lead the fight against malaria, especially WHO, UNICEF and USAID.  Sadly, the hoaxsters have friends in Congress who threaten to withhold funding to fight malaria, often insisting that now-mostly-ineffective DDT be used instead of good, working preventive measures and medicines to cure humans of malaria.

And so, Nothing But Nets writes to ask for help:

Email your members of Congress and let them know that you support full funding for malaria prevention programs.                                       

Dear Ed,

Imagine this: working from 4:00 AM until well into the night, getting very little sleep, traveling along unpaved roads for hours at a time – all to deliver 2,000 bednets per day to the hardest-to-reach children and families.

Email your members of Congress and let them know that you support full funding for malaria prevention programs.

Take Action

In Mozambique, this is a typical day for health workers as they distribute nets to save lives as part of a campaign funded by the Global Fund to Fight AIDS, Tuberculosis and Malaria. Thanks to the work of the Global Fund and other partners – including UN agencies and local communities on the ground – bednet coverage in Mozambique has gone from less than 5 percent of the population in 2000 to an impressive 60 percent today.

But without continued support from Congress, the life-saving impact of these nets could be lost.

Your member of Congress will vote soon on how much assistance the U.S. will provide to the Global Fund, along with partners like the President’s Malaria Initiative and the United Nations, the core agencies leading the fight against malaria. By showing your support to your representatives in Washington, you can help to make them champions in the fight against malaria and ensure that these bednets continue to make it to families who need them the most.

Thousands of people have already asked their members of Congress to support the crucial work of the Global Fund and other partners in the fight against malaria—will you join them today?

From all of us at Nothing But Nets, thanks for helping community health workers reach the last mile!

Dan Skallman
Senior Campaign Associate, Nothing But Nets

Original story and photo from The Global Fund to Fight AIDS, Tuberculosis and Malaria.

Take Action


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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