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4. What is being done to prevent and treat malaria?

  • 4.1 Which policies and strategies have been adopted?
  • 4.2 How many people at risk of malaria are covered by prevention measures?
  • 4.3 How many people were covered by diagnosis and treatment measures?
  • 4.4 What is the situation in the WHO African Region?
  • 4.5 What is the situation in other regions of the world?

4.1 Which policies and strategies have been adopted?

The WHO developed policy recommendations to prevent, diagnose and treat malaria. The extent to which these policies are adopted varies between countries (see overview table by region).

With regard to malaria prevention, the WHO recommends the use of mosquito bed nets treated with long lasting insecticide and indoor spraying to control the numbers of infected mosquitoes.

By the end of 2006, nearly all 45 countries in the WHO African Region had adopted the policy of providing free insecticide-treated nets to children and pregnant women, but only 16 of these countries aimed to cover the whole population at risk. Nets are also used in many countries in the South-East Asia and the Western Pacific WHO Regions, but in relatively few countries in other WHO Regions.

Spraying the inside of houses with insecticide is the main method used in the WHO European Region to reduce the numbers of infections, especially in Azerbaijan, Tajikistan and Turkey. This method is less used in the WHO Regions of Africa, the America’s and South-East Asia, and least used in the Western Pacific region.

Approximately half of the countries where malaria is endemic have strategies for avoiding and managing insecticide resistance of malaria-carrying mosquitoes.

Another prevention measure consists in giving at least two treatment doses of anti-malarial drugs during pregnancy to decrease the impact of malaria in pregnant women and newborns. This preventive method is only used systematically in 33 countries of the WHO African Region.

With regard to malaria treatment, the WHO recommends a “combination therapy” of several anti-malarial drugs including an artemisinin derivative as first-line treatment. Since 2001, this measure has become increasingly popular and, by 2008, only Cape Verde, Dominican Republic, French Guyana and Swaziland had not adopted it. Free treatment with combination therapy is widely available in the WHO South-East Asia Region (eight out of ten countries) but less so in the WHO Western Pacific Region (6 out of 10 countries) and in the WHO African Region (23 out of 46 countries).

In 2001, the WHO reached an agreement with the pharmaceutical industry Novartis to make a particular drug combination (Coartem ®) available at cost price (i.e. at a price excluding profit to Novartis) through public health services. During 2006 and 2007 most of these drugs were bought for children below 15 kg, predominantly in the African and South-East Asia WHO Regions. UNICEF and several other humanitarian aid agencies have made agreements with Novartis to buy the drug at the same price negotiated by the WHO.

In 2007, the WHO urged Member States to discourage or forbid the use of tablets containing a single anti-malarial drug derived from artemisinin, to promote artemisinin-based combination therapies and to forbid the distribution of fake anti-malarial medicines. By 2007, more than half of the drug companies identified by the WHO had said they would stop producing tablets with a single anti-malarial agent based on artemisinin. However, only one quarter of the countries had introduced measures leading to the withdrawal of these single anti-malarial medicines.

Table 4.1 Number of countries having adopted WHO-recommendations for malaria control

This text is a summary of: WHO, World Malaria Report (2008) ,
4. Interventions to control malaria, Adoption of policies and strategies for malaria control, p.16-18

4.2 How many people at risk of malaria are covered by prevention measures?

The main method of preventing malaria in high risk areas with one or more malaria cases per 1000 inhabitants per year is the use of insecticide-treated bed nets and the spraying of insecticide on the inside walls of houses.

Insecticide-treated nets:

Since 2004, the supply of conventional insecticide-treated nets (ITNs), which are assumed to be effective during one year, appears to have increased in the African, South-East Asia and Western Pacific WHO Regions.

In the WHO African Region, much more strikingly, the supply of long-lasting insecticidal nets (LLINs) which are effective for three years have increased tremendously from 2005 onwards. Overall about 66 million nets were distributed in Africa in 2006, which is still far below the estimated 324 million nets that were needed in the region that year. For instance, only 6 out of the 45 countries in the WHO African Region had sufficient nets by 2006 to cover at least 50% of people at risk (see coverage by country).

In this WHO Region, there is a wide variation in the ownership and use of mosquito nets among countries, ranging from 65% in Niger to 6% in Cote d’Ivoire, but all remain well below the WHO target of 80% coverage by 2010. According to surveys carried out in 2006–2007, on average, about a third of African households owned at least one net but only about a quarter of all pregnant women and children under five years slept under a bed net (see ownership and usage by country).

Outside the WHO African Region, treated nets are targeted at populations that are at the highest risk, including children, and therefore only protect a small proportion of the population. Data indicate that a relatively high coverage was achieved in Bhutan, Papua New Guinea, Solomon Islands and Vanuatu with more than 20% of all people at risk having access to insecticidal nets (see coverage by country).

Indoor spraying of insecticide:

In all regions of the world, indoor spraying is typically used only in locations where risk is the highest. In 2006, indoor spraying protected more than 100 million people, including 22 million in the WHO African Region and 70 million in India.

In the WHO African Region, more than 70% of households at any risk of malaria had their walls sprayed with insecticide in Botswana, Namibia, Sao Tome and Principe, South Africa and Swaziland. In 9 out of 11 countries providing information, coverage would have been sufficient to protect at least 10% of the population at risk.

Outside the WHO African Region indoor spraying of insecticide is targeted and coverage of populations at risk remains quite low in many countries. Only in Bhutan and Suriname did it exceed 20%. In 2006 only 11 countries sprayed enough houses to protect more than 5% of the population at risk (see coverage by country).

This text is a summary of: WHO, World Malaria Report (2008) ,
4. Interventions to control malaria, Coverage of interventions, p.18-20

4.3 How many people were covered by diagnosis and treatment measures?

Only 16 million rapid diagnostic tests were delivered in 2006, of which 11 million were for countries in the WHO African Region. This is a small quantity compared with the number of malaria cases. Distribution was very uneven and Ethiopia received more than 90% of the diagnostic tests attributed to the WHO African Region. Of the 4.8 million tests distributed outside the WHO African Region, more than half were used in India.

Between 2001 and 2006, public health services distributed an increasing number of anti-malarial drugs (80 million complete treatments in 2006) to treat approximately one third of all cases. In 2006, there was a large increase in the distribution of artemisinin-based combination drugs: it rose from 6 million in 2005 to 49 million in 2006, 45 million of which were for countries in the WHO African Region. Other sources indicate that these figures are probably underestimates. Most of the drugs were distributed in a limited number of countries and access to treatment varied widely. In any case, achievements for all treatment indicators are well below the WHO target of 80% coverage by 2010.

In Africa, treatment with any anti-malarial drugs ranged from 10% in Ethiopia to 63% in Gambia, and artemisinin-based combination therapies from 0.1% in Gambia to 13% in Zambia. Overall, only 38% of children under five years of age with fever took an anti-malarial drug, and 19% took it on the same day that the fever is detected or the next day.

Just 3% of children in the 18 African countries surveyed were given artemisin-based combination drugs. Besides Zambia, only Sao Tome and Principe gave them to more than 5% of children with fever (see figures by country).

On average, less than one pregnant woman in five received preventive treatment. This ranged from 0.3% in Niger to 61% in Zambia (see figures by country).

In WHO Regions other than Africa, twelve countries distributed more than one complete treatment course per malaria case through public health services. Bhutan, Laos, Papua New Guinea, Vanuatu and Viet Nam were among the best provisioned countries.

Access to anti-malarial drugs is better in cities compared to rural areas. For instance, the proportion of children under five years of age treated with anti-malarial drugs on the same day the fever appears or the following day was on average 27% higher in urban areas.

The proportion of malaria patients who sought treatment in the private sector was relatively high in South-East Asia and the Eastern Mediterranean WHO Regions, and low in the European and American WHO Regions. In the African and the Western Pacific WHO Regions, treatment was divided almost equally between the public and private sectors.

This text is a summary of: WHO, World Malaria Report (2008) ,
4. Interventions to control malaria, Diagnosis and cased management, p.20-22

4.4 What is the situation in the WHO African Region?

Child holding mosquito net in Togo. There are still
                                        insufficient numbers of nets in many countries.
Child holding mosquito net in Togo. There are still insufficient numbers of nets in many countries.
Source: Leslie Hallman

The general picture for the WHO African Region is that despite some progress, most countries are far from meeting targets for prevention and cure (see question 4.2 & 4.3 respectively).

In 2006, one third of the households in the 18 countries surveyed owned an insecticidal net and one quarter of children and pregnant women slept under a net. Overall, up to 39% of people at risk of malaria in the WHO African Region could have been protected in 2007 but this figure is still well below the WHO target of 80% by 2010.

Indoor spraying is typically used in specific high-risk areas (i.e. with one or more malaria cases per 1000 inhabitants per year). Mozambique and Zimbabwe covered an estimated one third to one half of their population at risk, but much higher coverage was achieved in Botswana, Namibia, Sao Tome and Principe, South Africa and Swaziland.

One in five pregnant women in 16 African countries surveyed received anti-malarial drugs as a preventive treatment.

With respect to drug availability, there is a large gap between provision and need. The countries with the best provisioned health systems are Botswana, Comoros, Eritrea, Malawi, Sao Tome and Principe, Senegal, Tanzania and Zimbabwe. Older anti-malarial drugs are less effective and their use is steadily declining while the supply of alternative drugs such as artemisinin-based combination drugs is bound to increase. Supply is especially high in Eritrea, Sao Tome and Principe, and Tanzania; but at present is still insufficient to fulfil the need.

Access to treatment is difficult to estimate but is clearly inadequate and well below of the 80% target. About one in three children with fever got some anti-malarial drug in 2006, but only one in 33 was given the more effective artemisinin-based combination therapies, even though there has been a big increase in its supply. There is much variation in access to treatment among and within countries, and it is better in cities than in the countryside.

A small group of African countries are performing well and there are some hopeful signs that prevention and treatment initiatives are starting to reduce malaria cases and deaths in some of these countries (see also question 6.2).

This text is a summary of: WHO, World Malaria Report (2008) ,
4. Interventions to control malaria, WHO African Region, p.23-24

4.5 What is the situation in other regions of the world?

Outside the WHO African Region it is more difficult to estimate the coverage of prevention and treatment programmes because of several reasons:

  • Only people at relatively high risk are targeted by prevention measures and the numbers involved are not reported to the WHO.
  • There are no records on the patients who do not use the public health system.
  • Household surveys are infrequent.

Data reported here are very uncertain and could give an unduly pessimistic view of malaria control in these regions.

In terms of prevention, coverage with insecticidal nets is relatively high in Bhutan, Papua New Guinea, Solomon Islands and Vanuatu. Coverage of indoor spraying with insecticide is also comparatively high in Bhutan, Solomon Islands and Suriname (see also question 4.2).

In terms of treatment, the countries best provisioned with anti-malarial drugs are Bhutan, Laos, Nicaragua, Turkey, Vanuatu and Viet Nam (see also question 4.3).

In some of the countries where prevention and treatment programmes have reached large proportions of people at risk (e.g. Bhutan, Laos and Viet Nam) the numbers of malaria cases and deaths have fallen. It seems that malaria control has had a significant impact on disease burden in these countries.

This text is a summary of: WHO, World Malaria Report (2008) ,
4. Interventions to control malaria, Regions other than Africa, p.25-26


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