How does malaria continue to kill millions?

May 05, 2014

On the April 25, 2014, Uganda joined the rest of the world to commemorate world malaria day under the ambitious theme: “Invest in the future: Defeat malaria

By Alex Turyatemba

trueOn the April 25, 2014, Uganda joined the rest of the world to commemorate world malaria day under the ambitious theme: “Invest in the future: Defeat malaria”.

A closer look at the statistics reveals a country that is not close to defeating malaria and is perhaps investing so much in the wrong areas.
 

According the The New Vision of April 25, malaria kills one Ugandan every three minutes. In every one hour, therefore, about 17 people lose their lives while in a single day, malaria strikes down 33o lives.

At 116,800 deaths a year, malaria is the leading cause of death in Uganda. The biggest proportions of these deaths are children below five years and pregnant mothers.
 

Dr. Myers Lugemwa, who heads Uganda’s malaria control programme at the ministry of health says the disease accounts for 30-50% of outpatient attendances at health facilities, 29% of inpatient admissions and 9-14% of in –patient deaths.

More than 90% of Ugandans are exposed to malaria with varying degrees of endemicity.

WHO estimates indicate that an African child dies from malaria every 30 seconds; three times the toll from AIDS. Africa has 86% of the estimated 300 million episodes and 91 % of malaria related deaths worldwide.

The irony of this is that, unlike AIDS, malaria has the advantage of being both preventable and curable.

The economic cost of this 135 year old disease is staggering: African countries continue to spend $12b even though the disease could be controlled at the fraction of that amount.

According to the Ministry of Health, Uganda spends sh25b on malaria fight or sh40,000 per person per year. This is 10% of the total health budget. 14% of absenteeism in schools is due to malaria while poor performance is also attributed to the same. As many succumb to the disease, many more are left too sick to work.

At Health Centre IIIs, where villagers line up for free medicines, long lines of mothers with sick babies strapped across their backs are a common sight.

This is the time they would otherwise put in productive work. Uganda, experts say, lags behind more than 30 years in development due to malaria. Indeed, there is no other health problem so deeply linked to our prosperity.

The signing of the Abuja declaration in 2000 was inspired by the realisation that Africa cannot achieve millennium development goals without fighting (and winning) the battle against malaria.

This saw the birth of Africa Malaria Day, which later metamorphosed into the World Malaria Day that we celebrated a while ago.

 

WHO now recognizes 4 frontiers on which to combat malaria: Case management with modern antimalarials like artemesinin- based combination therapy (ACT), Intermittent preventive treatment in pregnancy, Long lasting insecticidal bed nets, Indoor residual spraying with insecticides like DDT.

A survey conducted in 18 most affected countries revealed that only 34% of households surveyed owned an insecticide treated net.

According to the report, despite big increases in supply of mosquito nets in Africa, the number is still far below needed in almost all countries. Only 27% of pregnant mothers and 23% of children below five years in surveyed countries slept under mosquito nets.

Uganda’s mosquito net coverage is less than 15% (WHO recommends 90%).Most people are too poor to buy or even use a mosquito bed net.

The procurement of antimalarial medicines through public health services increased sharply but access to treatment especially artemesinin based therapies was in adequate in all countries surveyed.38% of children were treat with antimalarials but only 3%with ACT.
 

Access to ACT in Uganda stands at 15 %( WHO recommends 80%) and only 60% of pregnant women receive intermittent treatment against 90% recommended by WHO. The cost of these new effective drugs is also prohibitive; in a country where some live on less than a dollar a day.


The development of parasite resistance is among other factors linked to costly treatments. In the late 1990s, the first reports arrived from Cambodia of Malaria patients failing to respond to artemesinin treatments.

An investigation by Paul Newton of the welcome Trust south East Asia, revealed that the problem was the widespread use of cheap counterfeit drugs which had out-competed the highly priced genuine ones.

Back in the 1940s chloroquine was an effective treatment against malaria before misuse in south east Asia and Africa made it ineffective around the 80s.

High costs make poor people fail complete their doses-they start sharing doses while others stop taking tablets when they feel better and hand the balance over to the severely ill or keep it for the next episode.

This is sweet music to the parasite-it has a chance to survive and proliferate and conquer a similar dose and eventually the patient.

For decades the best treatment of malaria was an inexpensive medication called chloroquine, first discovered in Germany in 1934 by a researcher working for Bayer.

Chloroquine was so effective that it seems it might vanquish malaria forever. But by 1970s, the drug had been used so widely to treat all kinds of fevers, not just those caused by malaria, that the malaria parasites became resistant that doctors were compelled to turn to a second medication, called sulfadoxine-pyrimethamine, or SP (commonly known as Fansidar).

Within five years, the parasites started to develop resistance to Fansidar as well. Today those two drugs are not in use anymore.
 

Then doctors discovered that combination therapy, in which at least one of the medications is derived from a plant in Asia called Artemisia annua, or sweet wormwood, easily destroys drug resistant malarial parasites in the blood stream.

Using several drugs at once, often in the same pill, greatly decreases the risk that the parasites will become resistant.

As an added bonus, artemesinin, the active ingredient in artemesia annua was found to act very quickly, further decreasing the chances of drug resistance.

But the full three day course of treatment with artemesinin-based combination therapy costs is still too costly and that alone can bring about drug resistance. Neither poor village dwellers nor their impoverished governments can sustainably afford the therapy.
 

Many African governments and NGOs are working so hard to distribute low cost insecticide treated mosquito nets. The nets function as traps for mosquitoes, which are attracted by the carbon dioxide that sleepers exhale and are then killed by the insecticide.

In villages where at least 80% of pregnant women and children under age five sleep beneath insecticide treated mosquito nets, the rate of illness for all residents has dropped dramatically.

Unfortunately, only 1% or 2%of people in malarial zones sleep under mosquito nets. Additionally, most nets need to be retreated every six months, and are less effective in places where anopheles mosquitoes bite all day long instead of just at night.
 

The Roll Back Malaria campaign which had hoped to cut malaria rates by a half by 2010 relied heavily on bed nets and drug therapies and refused to pay due attention to the use of DDT.

The result has been an increase in malaria by more than 12 % during the programs decade of existence. WHO has had more than 8 chiefs of its malaria programs in the last 13 years but none has beaten the malaria figures using bed nets, chloroquine, fansidar, Quinine and more recently artemesinin many of which have been rendered less helpful due to parasite resistance.

Doctors now prescribe combinations of these drugs which worsen the economics of the malaria fight in a low budget country like Uganda. Maintaining a steady stream of these drugs is untenable given our economic situation. Health care providers have so much to do with a severely limited resource envelope.

Based on historic and contemporary evidence, the best -and most cost effective- way of controlling malaria available to us now is spraying tiny amounts of DDT on the inside walls of houses where it either kills or repels the notorious mosquitoes. When used carefully in scientifically monitored programs, DDT poses no threat to humans and the environment in general.

Interestingly, DDT is often better at repelling mosquitoes than at killing them. This means that much less pesticide than was once sprayed on water and swamps.

Large scale IRS with DDT for malaria control started in 1946 until the early 1970s when it was demonized by environmentalist fundamentalists claiming that it was destroying the environment.
 

Despite decades of extensive scientific research, there is still no plausible evidence on the health effects of DDT. According to Dr. Roger Bate, director of a South African NGO fighting malaria, “after 50 years, there is still not one replicated study that shows any harm to humans at all”.

The association of American Physicians, after numerous studies confirmed that DDT is not a carcinogenic (cancer causing) hazard to humans. Indeed in 2003, an international anti-pesticide treaty made an exception for use of DDT in malaria areas.
 

In 2006, the world health organisation strongly endorsed the chemicals use on indoor walls as a cheap and long lasting weapon in the fight against malaria. The United States also sanctioned DDT to combat the disease in African countries with a high burden of Malaria.
 

In Uganda,DDT was first used in the then Kigezi District from 1959 to 1963 to enable the Bakiga settle in queen Elizabeth national park which was originally occupied by animals.

These people were transferred from kisoro Nyalusiza to Kihihi, the current Kanungu district. People who were migrating there were dying from malaria.
 

Dr. Lugemwa says studies carried out through collecting samples from people who lived at that time indicate that although they have had DDT in their blood for the last 40 years, they are healthy. He says if DDT was to cause importance of infertility as the skeptics say, those people, especially from Kigezi would not be having children.

There is now consensus among scientists, Public Health authorities and international health agencies that the use of DDT for indoor residual spraying should be the primary tool for malaria prevention. Reason?
 

DDT lasts longer, costs less and is more effective against malaria. No other insecticide or bed net at any cost works as well.

A single small dose treatment lasts up to 8 months against 8 hours of the most active ingredient in mosquito repellants currently accepted worldwide. This dose keeps 90% of mosquitoes from entering the home, irritate any that come so they don’t bite and kills many that land on the inside of the walls. In this way virtually no DDT enters the environment and the results are astounding.

Recent experience in South Africa shows just how well DDT can work. In 1996 the South African government, under pressure from international and domestic environmental groups, decided to phase out its use of DDT in residential spraying and rely instead on pesticides containing pyrethroids.

The number of cases of malaria, which had been hovering between 8000 and 13000 a year, grew steadily worse, and by the year 2000 it had reached 64000 cases, with 423 deaths.
 

When President Mbeki’s government reintroduced DDT in the middle of 2000, the results were dramatic. The number of cases fell almost immediately.

By the end of 2001 when doctors began treating their patients with coatem, a single, multidrug pill that includes an artemesinin derivative, the number of cases had been cut in half. In 2003 the number of cases was down to 146.
 

Another greater (and successful) use of DDT was in the northern Uganda districts of Apac and Oyam in 2008. Apac district, statistics indicate, had the highest malaria rates in the world with 1564 effective bites per person per year-10 mosquito bites per night when one went to bed.

There was a dramatic reduction in malaria cases when, in 2008, MOH teamed up with the United States to use DDT to reduce the prevalence of mosquitoes.
 

DDT has been successfully implemented in over 19 countries in Africa including southern Africa countries (Mozambique, SA, Swaziland and Zimbabwe) and in countries where malaria is highly seasonal (Eritrea, Ethiopia and Madagascar).
Even Europe and USA used DDT to rid themselves of malaria.

No country anywhere in the world ever conquered malaria without using DDT .Indeed to very few other chemicals does humanity owe so much than it does to DDT.

Unlike drug therapies, to which the parasite now has resistance, there is no danger of mosquitoes developing resistance to DDT since the chemical is no longer used in agriculture.

Insecticide resistance is known to be more driven by agriculture than public health use. In Public health interventions like indoor residual spraying as opposed to agriculture, small doses are used and there is more control.

Indeed if DDT had only been used strictly for medicinal purposes, it might never have acquired its toxic reputation. The chemical would have been used to eradicate malaria and save millions of lives that malaria continues to claim. But it is never too late to start doing the right thing.

 

 

The writer is a lecturer at Medicare Health Professionals College.

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