Wüstenschiff

Novartis: FDA erteilt Coartem gg. Malaria vorrangige Zulassungsbehandlung
15.09.2008 - swissinfo

Basel (AWP) - Der Pharmakonzern Novartis AG hat von der US-Gesundheitsbehörde FDA die vorrangige Behandlung (priority review) des Zulassungsantrages für das Medikament Coartem (Artemether 20 mg / Lumefantrine 120 mg) zugesprochen erhalten. Die "priority review" für Coartem sei aufgrund des Therapie-Potenzials des Wirkstoffes erfolgt, teilt Novartis am Montag mit. Die Kombinationstherapie auf Artemisinin-Basis (ACT) sei weltweit die führende Malaria-Therapie und werde von der Weltgesundheitsorganisation (WHO) empfohlen, so die Mitteilung weiter. Sie werde bereits in Afrika eingesetzt. Coartem könne nun die erste Malaria-Therapie werden, die von der FDA zugelassen sei. Die dreitägige Kombinationstherapie Coartem weise Erfolgsraten von 96% auf und dies auch bei gegen andere Behandlungsformen resistenten Patienten ... mehr

Gruß
Birgitt

In der Subsahara stirbt eines von fünf Kleinkindern an Malaria

Genf - Alle 30 Sekunden stirbt ein Kind unter fünf Jahren an Malaria. Die Krankheit bleibt damit die Haupttodesursache für Kleinkinder, wie die Weltgesundheitsorganisation (WHO) und das Kinderhilfswerk UNICEF in ihrem Weltmalariabericht schreiben. mehr...

Grüsse
Alexander

Tropenmedizin
Die Fratzen eines Massenmörders
ZEIT ONLINE - 09.10.2008

Forscher haben das Erbgut zweier Malaria-Erreger entziffert - und sind erstaunt darüber, wie wenig sie bislang über den tropischen Killer wussten ... mehr

Gruß
Birgitt

Vatikan: Das Thema „Malaria“ darf nicht beiseite geschoben werden

Malaria, eine der tückischsten Krankheiten weltweit, soll laut Beschluss der UNO in den nächsten Jahren stärker bekämpft werden. Eines der Kernstücke der Anstrengungen soll eine drei Milliarden Dollar teure neue Initiative zur Bekämpfung der Malaria sein, von der sich die UNO die Rettung von 4,2 Millionen Menschenleben bis zum Jahr 2015 verspricht. Das Geld für den globalen Malaria-Aktionsplan (GMAP), das bisher ehrgeizigste Projekt dieser Art, kommt von der Weltbank, den UNO-Mitgliedsstaaten und privaten Stiftungen wie jener des Microsoft-Gründers Bill Gates, der 168,7 Millionen Dollar beisteuert. mehr...

Grüsse
Alexander

Kanada unterstützt bahnbrechendes Programm zur Behandlung von Malaria in afrikanischen Ländern südlich der Sahara

Washington (ots/PRNewswire) - Population Services International (PSI) startet ein neues umfassendes Projekt, das die Anzahl afrikanischer Kinder, die jährlich an Malaria sterben, dramatisch reduzieren könnte. Im Rahmen dieses Programms sollen in Armut lebende Kinder, bei denen Verdacht auf Malaria besteht, kostenlos mit einer Artemisinin-basierten Kombinationstherapie (artemisinin-based combination therapies; ACT) behandelt werden, die durch örtliche Gesundheitsdienste verabreicht wird. mehr...

Grüsse
Alexander

Erfolg gegen Malaria
09.12.2008 - Süddeutsche Zeitung

Im Kampf gegen die Seuche Malaria zeichnet sich Hoffnung ab. Ein an Kindern und Säuglingen in Kenia und Tansania getesteter Impfstoff habe erstmals einen "bedeutenden Schutz" vor der Infektion mit dem Malariaerreger gezeigt, teilten Wissenschaftler am Montag mit. Das sei das Resultat zwei großer Impfstoffstudien ... mehr
_______________________________

„Zwei Drittel sind ein großer Erfolg“
Tests mit Malaria-Impfstoff zeigen gute Ergebnisse
09.12.2008 - Deutschlandfunk

Medizin. - 250 Millionen Menschen erkranken jedes Jahr an Malaria, eine Million sterben daran. Eine Impfung ist bislang nicht in Sicht gewesen, alle Vakzin-Kandidaten scheiterten bislang. Im "New England Journal of Medicine" wird nun von einem neuen Impfstoff berichtet. Der Wissenschaftsjournalist Martin Winkelheide berichtet darüber im Gespräch mit Marieke Degen ... mehr


Gruß
Birgitt

MALARIA - KENYA: BED NETS USED FOR FISHING
******************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>

Date: Fri, 12 Dec 2008
Source: Daily Nation
<http://www.nation.co.ke/News/regional/- ... /6lp0kn/-/



Bed nets for malaria used for fishing
-------------------------------------
The green net stands out in a heap of fishing gear in one of the boats at
Liunda Beach on the shores of Lake Victoria in Bondo District. It is a
mosquito net that has been turned into fishing gear.

Intended for the bedroom to combat malaria, mosquito nets are fast finding
a new role. This turn of events is raising concern among public health
experts and fisheries managers. Apart from reversing the gains made in the
fight against malaria, this misuse also poses a risk to fish stocks in Lake
Victoria.

According to Dr Ayub Manya, a senior official in the Ministry of Public
Health, the use of mosquito nets among women and children in fighting
malaria remains abysmally low in Bondo although the district leads among
the areas in the country that have received nets.

The district has received a substantial number of nets from the Government
and non-governmental organisations. This year, more than 20 000 nets have
been distributed. District deputy public health officer Asher Okanga says
about 3000 malaria nets received in November last year were distributed in
the area in April. A further 21 279 nets received from the Kenya Medical
Research Institute/Centers for Disease Control and Prevention and other
organisations have also been distributed in the district in a recently
concluded campaign against malaria.

This is in addition to the 46 000 that were distributed in 2006. But
instead of using the nets against the killer disease, Dr Manya says,
communities along the lake are turning them into fishing gear. He says some
people are using the nets to dry small fish, locally known as omena.

In a recent net treatment programme conducted countrywide, most of the
residents in Bondo District turned up with torn nets for exchange.
Concerned by the trend, the Public Health ministry, in conjunction with
public health institutions, decided to change the colour of the mosquito
nets to differentiate them from the white fishing ones. However, this has
not helped matters. Mr Okanga says the green-coloured nets are still
finding their way onto beaches.

During routine patrols by a team of public health officials on the beaches
last week, he adds, fishermen were found to be using them openly. "It is
easy to differentiate mosquito nets from the rest since they are made from
nylon material," he explains. The misuse of bed nets has not been reported
in Bondo District alone.

A recent study conducted jointly by researchers from Maseno University's
School of Public Health, the International Centre for Insect Physiology and
Ecology and Nagasaki University in Japan reported similar findings in Suba
District.

The study, whose findings were published online in a recent issue of the
Malaria Journal, discovered that up to 83 per cent of beach areas in 7
major fishing villages in Gembe West sub-district in Suba was covered by
the mosquito nets. They were used for drying the fish.

Sustainability
--------------
In total, 283 mosquito nets were found to be in use. There were also 72
cases where the nets were used for fishing. Apart from reversing the gains
made in the fight against malaria, the misuse of the nets poses a threat to
the already declining stocks in Lake Victoria. Fisheries managers say the
small mesh sizes of the mosquito nets could catch juvenile fish, thus
threatening the sustainability of the resource.

--
communicated by:
ProMED-mail
<promed@promedmail.org>

[The description of misuse of mosquito bednets is a worrisome
observation/reality. From a distance it is easy to attempt to criticize
program activity failures as due to a lack of health education to ensure
that the impregnated bednets are used as malaria prevention tools, but
economic realities set in, and if one's livelihood is at stake, the option
is to have food on the table and access to anti-malarials rather than to be
potentially malaria free, but without food on the table. This highlights
the need for medical anthropologists and health communication specialists
to resolve these challenges. - Mod.MPP

From the point of the population it may make sense to prioritize economic
income from fishing compared to malaria control. ProMED-mail would be happy
to publish suggestions for how such a situation is to be addressed. – Mod.EP]

Governments in West Africa must step up existing measures to prevent the spread of malaria



DAKAR, 22 December 2008 (IRIN) - The world’s most clinically advanced malaria vaccine trials have given new hope in the fight against the disease, which in sub-Saharan Africa kills a child every 30 seconds.

Malaria experts recently meeting in the Burkina Faso capital Ouagadougou say promising vaccine research aside, governments in West Africa must step up existing measures to prevent the spread of the disease.

Results published on 11 December in the New England Journal of Medicine showed that the vaccine candidate RTS,S/AS (made by GlaxoSmithKline (GSK) Biologicals), provides both infants and young children with significant protection against malaria.

“We are closer than ever before to developing a malaria vaccine,” said Christian Loucq, director of PATH Malaria Vaccine Initiative (MVI), the organisation coordinating the global effort.

The Roll Back Malaria (RBM) partnership says malaria is the leading cause of death of under-five children in Africa, and in pregnant women increases the chances of low birth weight, anaemia or early infant death.

Malaria is endemic in most West African countries. The World Health Organisation (WHO) says malaria causes an average loss of 1.3 percent of economic growth in countries with intense transmission.

Scientific success

Two separate ‘second phase’ trials of versions of the RTS,S/AS drug were conducted in Kenya and Tanzania, and reaffirmed earlier study results, supporting the launch of a further, ‘stage three’ trial.

In children aged five months to seventeen months, the candidate RTS,S/AS01 reduced the risk of clinical episodes of malaria by 53 percent, over an eight-month period. It was also shown to have a promising safety profile. And for the first time, data from the study of RTS,S/AS02 showed that the drug can be used in infants, as part of existing national immunisation programmes.

“The vaccine works alongside standard infant vaccines of the World Health Organisation’s (WHO) Expanded Program of Immunization (EPI), and has consistently shown a significant efficacy level,” said Joe Cohen, a co-inventor of the vaccine and vice-president of Research & Development, Emerging Diseases & HIV at GSK Biologicals.

Holistic approach

One RBM official, who took part in the Ouagadougou malaria conference, said the vaccine progress is welcome news but does not change the need for better prevention efforts in West Africa.

“This new research is positive but it doesn’t change our message – countries still need to modify their strategies, especially in prevention and treatment”, Boi-Betty Udom, RBM partnership facilitator, told IRIN. “We’re hopeful a vaccine could be part of a holistic approach to malaria control, as a way to reduce the severity of malaria attacks.”

At the Ouagadougou meeting WHO and RBM officials urged West African governments to work to reach more people with preventive measures. Udom said just 20 percent of people – mainly under-five children and pregnant women – are being targeted.

Stephan Tohon of WHO’s malaria programme in Burkina Faso said too narrow a focus might mean that preventive tools like insecticide-treated nets (ITN) are not being used as they should. “Ten years ago we focused on the most vulnerable populations – women and under-five children – but today we realise that where there is a mosquito net it’s often the head of the household who uses it.”

WHO’s latest world malaria report says surveys in 2006-07 in 18 African countries showed that 34 percent of households owned ITNs and 23 percent of under-five children slept under the nets.

Experts at the meeting noted that none of the countries in West Africa have met the African Union’s 2003 Maputo declaration, which stipulated that governments allot 15 percent of the national budget to the health sector.

www.irinnews.org

Grüsse
Alexander

Parasit hilft im Kampf gegen Malaria

Australische Forscher haben herausgefunden, dass ein parasitäres Bakterium die Lebenszeit von Insekten verkürzt. Damit können auch Moskitos bekämpft werden, die Malaria verbreiten. mehr...

Grüsse
Alexander

Malaria-Rezeptor in der Mücke gefunden

Amerikanische Forscher haben in der Speicheldrüse von Malaria-Mücken ein Rezeptormolekül gefunden, an das ein Protein des durch die Insekten transportierten Krankheitserregers bindet. Damit sei ein wesentlicher Prozess des Infektionszyklus von Malaria aufgeklärt, schreiben die Wissenschaftler. mehr...

Grüsse
Alexander

Malaria-Impfung geht in die nächste Phase

Untersuchungen zeigten Wirksamkeit von Vakzine - Phase-III-Studien könnten Anfang 2009 beginnen

Wien - Ein vom britischen Pharmakonzern GlaxoSmithKline entwickelte Malaria-Impfstoffkandidat schützt offenbar Säuglinge und Kleinkinder wirksam vor Malaria. mehr...

Grüsse
Alexander

Bei dem nachfolgenden Artikel handelt es sich zwar um die Reiseländer Thailand und Kambodscha,
aber die beginnende Resistenz gegen Artemisinin ist wohl für alle Traveller interessant:



MALARIA - CAMBODIA, THAILAND, ARTEMISININ RESISTANCE
****************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>

[1]
Date: Mon 26 Jan 2009
Source: The New York Times [edited]
<http://www.nytimes.com/2009/01/27/healt ... ia.html?hp>


The parasite that causes the deadliest form of malaria is showing the
1st signs of resistance to the best new drug against it.

Combination treatments using artemisinin, an antimalaria drug
extracted from a plant used in traditional Chinese medicine, have
been hailed in recent years as the biggest hope for eradicating
malaria from Africa, where more than 2000 children die from the
disease each day.

Now a series of studies, including one recently published in The New
England Journal of Medicine and one due out soon, have cemented a
consensus among researchers that artemisinin is losing its potency
here [in Cambodia] and that increased efforts are needed to prevent
the drug-resistant malaria from leaving here and spreading across the
globe.

Admiral R Timothy Ziemer, a retired admiral of the United States Navy
who heads the USD 1.2 billion President's Malaria Initiative, met with
Thai and Cambodian officials last month [December 2008] to assess the
resistance problem, which affects the same drugs used by the malaria
initiative in Africa.

Though the studies show relatively early signs of resistance to
artemisinin, the drugs were judged to have failed in only 2 patients
in the recently published study. Even they were eventually cured. But
malaria experts note that several times in the past, this same area
around the Thai-Cambodian border appears to have been a starting point
for drug-resistant strains of malaria, starting in the 1950s with the
drug chloroquine. It took decades for this resistance to spread
across the world, so by the same token, artemisinin-based drugs are
almost sure to be useful for many years to come.

To protect against artemisinin resistance, the global health
authorities are trying to assure that it is sold only as a
combination pill with other antimalaria medicines that linger longer
in the blood, mopping up any artemisinin-resistant parasites.

The 2 most recent tests showing artemisinin resistance were done with
pills that had no combination drug. But if resistance spreads, there
are no new drugs to take the place of artemisinin-based combinations
and no immediate prospects under development.

Pascal Ringwald, malaria coordinator at the World Health Organization
(WHO), who 3 years ago led a study of drug resistance in Cambodia, is
co-author of a coming study on the subject. "We know it's not yet in
Bangladesh," he said. "It's not yet in India." Scientists have
documented how malarial parasites that were resistant to chloroquine
in the 1950s spread across Thailand, Burma, India, and over to Africa,
where a vast majority of the nearly one million annual malaria-related
deaths occur.

To prevent a recurrence with artemisinin therapies, the United States
has put aside political considerations and approved a
malaria-monitoring center in military-run Myanmar, formerly Burma.
The Bill and Melinda Gates Foundation, one of the largest donors to
malaria research, is giving USD 14 million to the Thai and Cambodian
governments to help pay for a containment program.

That program includes efforts to supply the area with mosquito nets,
a screening program for everyone living in affected areas, and
follow-up visits by health workers to assess the effectiveness of the
drugs, said Dr Duong Socheat, director of Cambodia's National Malaria
Center. On the Thai side of the border, the government has
"motorcycle microscopists" who take blood samples from villagers and
migrant workers, analyze them on the spot, and distribute antimalaria
drugs. But some experts would like to see an even more aggressive
approach.

The falciparum parasite is one of 4 types of malaria and by far the
most virulent. It enters the bloodstream through a mosquito bite, and
after incubating about 2 weeks, it multiplies and takes over red
blood cells. There, it causes fever, chills, headaches, and nausea,
among other symptoms. If untreated, the infected cells can block
blood vessels and fatally cut off blood supply to vital organs.

The recent studies show that artemisinin-based drugs are becoming
less effective in removing the parasite from the bloodstream. While a
few years ago it took the drugs 48 hours to clear the bloodstream of
parasites, it now can take 120 hours.

"What our study demonstrates is that therapy for some patients fails;
the malaria goes away and comes back," said Lt Col Mark M Fukuda, a
United States Army doctor whose study was published in The New
England Journal of Medicine in December [2008].

Different regions rely on different artemisinin combinations. The
Cambodian government recommends that artemisinin be combined with
mefloquine, which was developed by the American military and is known
commercially as Lariam. Artemether, a derivative of artemisinin, is
often combined with another antimalarial drug, lumefantrine. This was
recently judged to be the most effective combination in a study of
children in Papua New Guinea.

The same combination is also expected to be approved for sale in the
United States soon, marketed by Novartis and mainly intended for
people traveling overseas or for those who arrive in the United
States with malaria.

The mosquito responsible for transmission of malaria is still endemic
in the United States. But modern housing, better access to health
care, and the use of insecticides have virtually eradicated the
disease in wealthier countries.

Dr Fukuda calls this region of Cambodia the "canary in the coal mine"
for drug resistance. In the past, migrant workers in plantations and
gem mines are believed to have helped spread drug-resistant strains
westward. A history of civil unrest, counterfeit drugs, and a weak and
underfinanced government have made it difficult to control malaria. In
the case of chloroquine, preventive use of the drug -- including
putting it in table salt to protect a wide swath of the population --
might have actually encouraged resistance to the drug, Dr Fukuda and
others say.

It was not until the 1990s that mefloquine, the American army drug,
was combined with artemisinin, made from a Chinese herb.
Artemisinin-based combinations turned out to be fast acting and seemed
to slow transmission of the disease, said Dr John MacArthur, an
infectious disease expert with the United States Agency for
International Development in Bangkok. Dr MacArthur and others say
resistance to malaria drugs is a natural consequence of widespread use
of the drug.

Still, some researchers remain concerned about sending the wrong
message to the public about the efficacy of artemisinin-based drugs.
"This is not the death knell of artemisinin," said Dr Nicholas White,
a malaria expert who is chairman of a joint research program between
Oxford University and Mahidol University in Thailand. "The drug still
works in Cambodia, [just] maybe not as well as before." But given the
history of drug failures here [in Cambodia], there appears to be a
consensus on the solution. "Get rid of all malaria from Cambodia," Dr
White said. "Eradicate it. Eliminate it."

[Byline: Thomas Fuller]

--
Communicated by:
ProMED-MBDS
<promed-mbds@promedmail.org>

******
[2]
Date: Tue 13 Jan 2009
Source: Thomson Reuters Foundation AlertNet, UN Integrated Regional
Information Networks (IRIN) News report [edited]
<http://www.alertnet.org/thenews/newsdes ... 0ed6fc.htm>


A deadly strain of malaria along the Thai-Cambodian border is
becoming increasingly immune to treatment, threatening the global
effort to end malaria, new evidence shows.

Artemisinin combination therapy (ACT), whereby patients take both a
fast-acting and slow-acting drug to kill the parasite, is losing its
therapeutic effects as treatment is taking longer.

"We are facing a problem that instead of killing the parasite within
24 to 36 hours as before, ACT now needs up to 120 hours to kill the
parasites," Pascal Ringwald, a medical officer at the World Health
Organization (WHO) in charge of monitoring anti-malarial drug
resistance, told IRIN from Geneva.

The parasite's resistance to artemisinin, one of 2 drugs in ACT
therapy, is the driving factor behind the deterioration of ACT.

Usually, doctors will prescribe artemisinin with one of many
slower-acting drugs. Yet the problem is not only artemisinin
resistance, which has existed since the 1970s, but rather tolerance to
ACT, the more advanced therapy consisting of 2 drugs, Ringwald said.
Artemisinin monotherapy refers to taking the drug alone and is not
recommended by the WHO.

"Artemisinin resistance appears in parts of Southeast Asia where
there has been rampant and uncontrolled use of artemisinin
monotherapy," Sir Richard Feachem, director of the Global Health
Group at the University of California at San Francisco, told IRIN.

At 1/10th the price of ACT and without its adverse side effects, such
as vomiting, artemisinin monotherapy continues to remain a popular
choice for many.

However, if the threat is not contained, resistant malaria will
spread through the region and hit poor communities in particular,
Feachem warned.

Duong Socheat, director of the National Centre for Parasitology,
Entomology and Malaria Control (see:
<http://www.cnm.gov.kh/indexs.htm>)
in Phnom Penh, told IRIN that ACT and outreach and prevention tools
like mosquito nets had seen remarkable progress despite a tolerance
threat. A total of 100 000 malaria cases were reported in 2006,
falling to 59 000 in 2007, and 54 000 in 2008.

The malaria death rate has been halved in only 2 years, from 396 in
2006 to 241 in 2007 and 184 in 2008.

At an emergency meeting in October [2008], the WHO recommended a
switch to a new ACT therapy called dihydroartemisinin-piperaquine
(DHA-PIP) for 2009, which is virtually 100 percent effective
according to new trial results in Cambodia.

The previous ACT treatment since 2001, artesunate mefloquine, is
still 90 percent effective but unpopular among at-risk populations
that still use monotherapy despite the ban.

Merchants often sell cheap, counterfeit monotherapies in rural areas.

The WHO also recommended wider distribution of mosquito nets,
stricter enforcement of the ban on monotherapies, and the rapid
deployment of WHO-endorsed drugs.

Yet malaria has been developing resistance to artemisinin for
decades, and ACT tolerance is only a new phase in the parasite's
evolution.

Since the 1970s, factors such as gem-mining migrants from all over
Southeast Asia mixing malaria strains at the Thai-Cambodia border, an
unregulated drug market, and overuse of artemisinin monotherapy have
all caused _Plasmodium falciparum_, a common malaria parasite in
Cambodia, to develop resistance to the drug.

The government and WHO responded by endorsing ACT in 2001 and banning
artemisinin-only therapy. But even ACT, despite being more than 90
percent effective against malaria, will need to be adapted soon,
Feachem said.

"Ensuring that artemisinin is always given with another drug in the
form of ACT is a clever use of a clever drug," Feachem said.
"However, parasite resistance will eventually catch up with this, and
for this reason, the development of new drugs ... is of the utmost
importance to the health of people worldwide."

Fake drugs and patients not complying with their treatment schedules
are other factors. "If people don't take their drugs regularly, then
they will have problems with resistance," Hou Nirmita, head of the
health department at the Ministry of Women's Affairs, told IRIN.

But Feachem, who thinks malaria could be eradicated worldwide by
2050, sees hope. "The challenge of drug resistance, and the fact that
we can never prevent the development of resistance in the long term,
provides a strong argument for the acceleration of elimination and
control efforts now," he said. "To delay or to implement programs in
a half-hearted manner is both expensive and dangerous," he explained.

According to the WHO World Malaria report for 2008 (see
<http://www.who.int/malaria/wmr2008/>),
half the world's population is at risk, and an estimated 247 million
cases led to nearly one million deaths in 2006. Pregnant women and
children in Africa are especially threatened, the WHO says.

--
Communicated by:
ProMED-MBDS
<promed-mbds@promedmail.org>

[The documentation of early indications of artemisinin combination
therapy (ACT) resistance/failure is disconcerting. The recent
significant inroads that have been made vis a vis reduction in
mortality rate associated with malaria will be threatened if
resistance to ACT increases. As mentioned in the newswires above,
there is precedence for development of antimalarial therapy
resistance on the Thai Cambodian border, first observed with
chloroquine therapy and later with other antimalarials. PRO/MBDS has
had a number of postings on the prevalence of counterfeit
antimalarials in the region, one factor that is felt to contribute to
the development of the resistance. Other factors include the use of
monotherapy with artemisinin alone (and suboptimal treatment of
cases), and the widespread use of antimalarials for febrile illnesses
without documentation that the illnesses were actually malaria.

Recent publications have been discussing the early signs of
developing ACT resistance. In a December 2008 letter to the editor of
the New England Journal of Medicine, Noedl et al described a study on
60 patients who received artemisinin therapy for _Plasmodium
falciparum_ infection in Cambodia. Of these 60 patients, 4 had
reemergence of parasitemia between days 21 and 28 after the start of
treatment, and 2 of these 4 patients (3.3 percent of total studied)
were classified as having artemisinin-resistant infection (see ref.
1). Wongsrichanalai and Meshnick discussed 3 published studies
demonstrating the early appearance of decreased efficacy of parasite
clearance associated with artemisinin-mefloquine combination therapy
near the Cambodia-Thailand border (see refs. 3-5).

Suggested references
--------------------
1. Noedl H, Se Y, Schaecher K, Smith BL, Socheat D, Fukuda MM:
Evidence of Artemisinin-Resistant Malaria in Western Cambodia. NEJM.
11 Dec 2008. 359 (24): 2619-2620, full article available at
<http://content.nejm.org/cgi/reprint/359/24/2619.pdf>.

2. Lim P, et al: Pfmdr1 copy number and artemisinin derivatives
combination therapy failure in falciparum malaria in Cambodia.
Malaria Journal 2009, 8:11, full article available at
<http://www.malariajournal.com/content/p ... 5-8-11.pdf>.

3. Wongsrichanalai C., Meshnick SR: Declining Artesunate-Mefloquine
Efficacy against Falciparum Malaria on the Cambodia-Thailand Border.
Emerg Infect Dis. 2008 May; 14(5): 716-9, full article available at
<http://www.cdc.gov/EID/content/14/5/pdfs/716.pdf>.

4. Denis MB, Tsuyuoka R, Poravuth Y, Narann TS, Seila S, Lim C, et
al: Surveillance of the efficacy of artesunate and mefloquine
combination for the treatment of uncomplicated falciparum malaria in
Cambodia. Trop Med Int Health. 2006; 11: 1360-6, full text available
at
<http://www3.interscience.wiley.com/cgi- ... 8/PDFSTART>.

5. Vijaykadga S, Rojanawatsirivej C, Cholpol S, Phoungmanee D,
Nakavej A, Wongsrichanalai C: In vivo sensitivity monitoring of
mefloquine monotherapy and artesunate-mefloquine combinations for the
treatment of uncomplicated falciparum malaria in Thailand in 2003.
Trop Med Int Health. 2006; 11: 211-9, full text available at
<http://www3.interscience.wiley.com/cgi- ... 0/PDFSTART>.
- Mod.MPP

It is not entirely unexpected that artemisinin resistance should
develop as it does with all antimicrobial agents. This part of the
world has been the hot spot for resistance starting with chloroquine
(1st report Moore DV, Lanier JE: Observations on Two _Plasmodium
falciparum_ Infections with an Abnormal Response to Chloroquine. Am J
Trop. Med Hyg. 1961; 10:5-9, abstract available at
<http://www.ajtmh.org/cgi/content/abstract/10/1/5>).

Two recent papers report artemisine resistance on the Thai-Cambodia
border:
1) Wongsrichanalai C and Meshnick SR:
Declining Artesunate-Mefloquine Efficacy Against _Falciparum_ Malaria
on the Cambodia-Thailand Border. EID 2008; 14: 716-9, available at
<http://www.cdc.gov/EID/content/14/5/pdfs/716.pdf>.

2) Noedl H et al: Evidence of Artemisinin-Resistant Malaria in Western
Cambodia. N Engl J Med 2008; 359: 2616-20, available at
<http://content.nejm.org/cgi/reprint/359/24/2619.pdf>).

Combination therapy with sulfadoxine/pyrimethamine and mefloquine
(FansiMef) was unable to prevent mefloquine resistance emerging in
Thailand. A recent study from Africa reports that 50 percent of _P.
falciparum_ isolates from Africa has increased inhibitory
concentration of lumefantrine, a drug commonly combined with
artemisinin, and this should be kept in mind in Cambodia as well.

Drug resistance develops when treatment is done with sub-inhibitory
concentration for too short a period. The practice of selling malaria
drugs as individual pills encourage underdosing and the problem of
fake drugs with either no drug or low content of the active compound
enhance the development of resistance. Thus, quality control of drugs
needs to be enforced and quality controlled -- perhaps more emphasis
on traditional prevention including impregnated bed nets and
screening of houses should be a priority. - Mod.EP]

For a map of Thailand, see
<http://www.lib.utexas.edu/maps/middle_e ... n_2005.jpg>.
For a map of Cambodia, see
<http://www.lib.utexas.edu/maps/middle_e ... pol_97.jpg>.

For the interactive HealthMap/ProMED maps of Cambodia, and Thailand
with links to other recent ProMED and PRO/MBDS postings on events in
these countries and surrounding countries, see
<http://healthmap.org/promed/en?v=12.7,104.9,5> (Cambodia) and
<http://healthmap.org/promed/en?v=15.1,101,5> (Thailand). - Mod.MPP]

Insecticide malaria impact clue
05.02.2009 - BBC

UK scientists have identified genetic differences in malarial mosquitoes which may reveal their level of resistance to insecticides. The find may help researchers work out which areas cannot rely on insecticides to help minimise the risk of malaria, reports the journal Genome Research. The Liverpool School of Tropical Medicine team linked two genes in one type of African mosquito to resistance. Another UK expert said similar genes might be at work in other varieties ... mehr

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Birgitt

Ein neuer Impfstoff bringt Hoffnung im Kampf gegen die Tropenkrankheit
20.02.2009 - Bilder der Wissenschaft

Malaria ist nach wie vor eine der bedrohlichsten Infektionskrankheiten. Jetzt zeigt ein neu entwickelter Impfstoff erste Erfolge in klinischen Studien – er könnte in Zukunft das Leben vieler Menschen retten. Der Wirkstoff regt die Bildung von Antikörpern an, die den Befall der Leber durch die Erreger verhindern ... mehr

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Birgitt

Drug resistance could set back malaria control success
US$ 22.5 million grant from Gates Foundation to contain malaria parasites resistant to artemisinin
25.02.2009 - WHO

GENEVA - WHO today said that the emergence of parasites resistant to artemisinin at the Thai-Cambodia border could seriously undermine the success of the global malaria control efforts.

Surveillance systems and research studies supported by WHO to monitor antimalarial drug efficacy in countries are providing new evidence that parasites resistant to artemisinin have emerged along the border between Cambodia and Thailand. If local people, who walk for miles every day to clear forests, were infected with a drug-resistant form of malaria, it could set back recent successes to control the disease.

Huge strides have been made in the past 10 years to reduce the burden of malaria, one of the world's major killer diseases. Strong malaria control programmes have helped to lower infection rates in several countries. The recent shift from failing drugs to the highly effective artemisinin-based combination therapies (ACTs) has been a breakthrough. Appropriate treatment with ACTs succeeds in more than 90% of cases. But malaria drug resistance now emerging along the Thai-Cambodia border threatens these gains.

With a US$ 22.5 million grant from the Bill & Melinda Gates Foundation, WHO will endeavour to contain artemisinin-resistant malaria parasites before they spread. WHO will work in collaboration with several key partners including the National Center for Parasitology, Entomology and Malaria Control of the Cambodian Ministry of Health, Bureau of Vector-Borne Disease of the Thai Ministry of Public Health, Faculty of Tropical Medicine of Mahidol University Bangkok, Institut Pasteur Cambodia, Mahidol Oxford Tropical Medicine Research Unit, Bangkok and the Malaria Consortium.

"If we do not put a stop to the drug-resistant malaria situation that has been documented in the Thai-Cambodia border, it could spread rapidly to neighbouring countries and threaten our efforts to control this deadly disease," said Dr Hiroki Nakatani, Assistant Director-General of WHO.

Resistance along the Thai-Cambodia border started with chloroquine, followed by resistance to sulfadoxine-pyrimethamine and mefloquine, drugs used in malaria control several years ago.

Malaria poses a risk to half of the world's population and more than one million people die of the disease each year. The malaria map, or the area where it is prevalent, has been reduced considerably over the past 50 years, but the disease has defied elimination in areas of intense transmission.

Obstacles to malaria control include drug resistance in the parasite that causes the disease, as well as resistance of the vector mosquito to insecticides, environmental factors and counterfeit medicines. The likelihood of drug resistance is increased with the use of single-drug therapies for malaria, especially monotherapies of artemisinin and its derivatives. Monotherapy fosters resistance because it is easier for the parasite to adapt and eventually overcome the obstacles presented by a single drug than a combination of drugs delivered together. This makes it crucial for monotherapies to be removed from the market. WHO's treatment policy is to treat all cases of uncomplicated falciparum malaria with artemisinin combination therapy (ACTs).

"We know that malaria can be treated and prevented,” said Dr Regina Rabinovich, Director of Infectious Diseases Development at the Bill & Melinda Gates Foundation, “and if we lose the key treatment available at this time, it's like living in a house with a half a roof.”

The grant will be used to meet the following key objectives:

• eliminate artemisinin-tolerant parasites by detecting all malaria cases in target areas and ensuring effective treatment;
• reduce exposure of the parasites to artemisinin to limit emergence of resistance
• prevent transmission of artemisinin-tolerant malaria parasites through mosquito control and personal protection
• limit the spread of artemisinin-tolerant malaria parasites by mobile populations
• support the containment and elimination of artemisinin-tolerant parasites through comprehensive behaviour change, communication, community mobilization and advocacy
• undertake basic and operational research to fill knowledge gaps and ensure that strategies applied are evidence-based; and
• provide effective management, surveillance and coordination to enable a rapid and high-quality implementation of the strategy

Quelle: WHO

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