A study recently published in The Lancet found that researchers in Tanzania were able to cut malaria incidence by two-thirds through a combination of anti-malarial drugs and iron supplements.

Malaria is especially lethal in infants and children because the malaria parasite destroys the red blood cells creating a life-threatening anemia.

Researchers with the World Health Organizations gave anti-malarial drugs and iron supplements to more than 700 infants as a part of their routine vaccinations. In that study group, malaria infections were cut by two-thirds, and anemia cases were halved.

Researchers have been reticent to use anti-malarial drugs preventively out of concerns that it might accelerate the rise of drug-resistant strains of the parasite. Dr. Pedro Alonso, who led the research project, said that if given as part of standard infant vaccinations, however, many of the concerns about using anti-malarials preventively could be addressed and the result would likely be slowing the rate at which drug-resistant forms of malaria are emerging.

The next step for WHO is larger trials of the treatment combination to test its safety and efficacy.

Source:

Tanzania baby malaria halved. The BBC, May 11, 2001.

African nations marked April 25, 2001 as the first Africa Malaria Day to highlight the continuing persistence of the diseases that kills more than a million people every year on the continent (90 percent of all malaria deaths occur in Africa according to the World Health Organization).

The BBC reported that UN agencies and others met in Nigeria to discuss ongoing plans at dealing with the disease. Several countries also were expected to announce that they were removing duties and taxes on malaria fighting technologies. This seems a bit absurd, but many countries in Africa apparently tax things like mosquito nets and have only recently removed such taxes.

In 2000 the Ivory Coast, Nigeria, Tanzania, Uganda and Zambia made such moves, and this year Ghana, Kenya and Mozambique were expected to join them. On the other hand, you have to wonder why such countries would have policies that raise the costs of dealing with such a widespread and deadly disease in the first place.

Like the AIDS epidemic in Africa, malaria is helped along by the endemic poverty in the region which makes it difficult for health care systems to deal with it. The BBC reports that in Zambia, for example, in 1980 there were about 12 deaths from malaria for every 1,000 malaria patients. Today, however, the are more than 60 malaria deaths per 1,000 malaria patients.

Source:

Africa tackles malaria scourge. The BBC, April 25, 2001.

Researchers at the Washington University School of Medicine are investigating a possible treatment for Malaria which acts by trapping the parasite in its protective sac. Trap the parasite long enough, and it simply dies before it can wreak havoc on the body.

Dr. Daniel Goldberg and his colleagues managed to successfully block malaria parasites in blood samples.

When malaria enters the human body, the parasites infect red blood cells and then surround themselves with part of the blood cell membrane to create a protective sac for the parasite to reproduce. The parasite replicates itself until it bursts the protective sac and then scatter to infect the bloodstream.

In blood cultures, Goldberg and other researchers treated the malaria with a drug that prevented the parasite from bursting from the protective sac. Eventually the parasite would deteriorate and no longer poses an infectious threat.

Much more research will be required to identify the specific mechanism that prevents the parasites from escaping the sac, and any possible treatment for human beings based on the finding is years away.

Source:

Scientists ‘block malaria’. The BBC, December 31, 2000.

After making significant progress against Malaria in the 1950s and 1960s, the disease is back and, in fact, rates of malaria incidence are increasing in many developing countries. Why?

One answer that has been increasingly common is that global warming is responsible for the rise in malaria. Some scientists have suggested that not only is climate change response for the current upswing but that continued warming temperatures could lead to a resurgence of malaria outside of the tropics. Fortunately such claims don’t hold up to scrutiny.

Although malaria today is thought of as a specifically tropical disease, in fact malaria used to be present pretty much everywhere in the world — as entomologist Paul Reiter told the BBC in September, the first major reported outbreak of malaria in the world occurred in Philadelphia, of all places, in the 1780s. As recently as the 1880s, malaria was a serious problem throughout all of North America and was present as far north as Finland.

Improvements in public health monitoring as well as increases in population density helped largely eliminate the threat of the disease toward the last decade of the 19th century. Thus it’s not too surprising to see malaria increases in cooler, highland countries of Africa such as Rwanda and Kenya. This is especially true when one takes into account the increased efforts at diagnosing and reporting malaria cases in countries such as Rwanda — UNICEF spent millions of dollars in the mid to late 1980s to improve Rwanda’s ability to track malaria cases, and its hardly surprising that Rwanda’s health authorities as a result found more cases of malaria.

The really sad thing about the vector-borne disease/global warming link is just how ill-informed the so-called experts were who made this claim in the Intergovernmental Panel on Climate Change’s 1996 report. As Reiter told the BBC, “The bibliographies of the nine lead authors of the health section show that between them they had only published six research papers on vector-borne diseases.”

Meanwhile, the Save the Children from Malaria Campaign fears that an ongoing anti-DDT campaign by environmental activists is discouraging the use of that pesticide to control malaria. Some countries have stopped using DDT altogether, and those nations have experience increases in malaria according to tropic disease expert Donald Roberts. Roberts notes that in Guyana, for example, malaria incidence increased 12-fold from 1984 to 1991 when that nation reduced its DDT spraying.

While much of the environmentalist fears about DDT are overblown, neither is DDT a magic bullet as disastrous and counter-productive government application of DDT proved in the 1950s and 1960s. DDT is an important tool, but to rid the world of malaria will require governments and non-governmental organizations to use the pesticide wisely.

Source:

Malaria rising as DDT use falls, scientist says. Reuters, November 22, 2000.

Warming ‘not spreading malaria’. The BBC, September 21, 2000.

Thanks to the excessive use of pesticides such as DDT in the 1950s and 1960s, many mosquitoes around the world now have a good deal of resistance to such chemicals. The emergence of pesticide-resistant mosquitoes and the subsequent failure to control malaria is generally considered one of the major lost opportunities to eradicate a deadly diseases.

Researcher Janet Hemingway claims there might be an upside to such resistance. In a study published in New Scientist, Hemingway reported that a variety of mosquitoes she captured that were resistant to organophosphate insecticides were also less able to transmit a disease caused lymphatic filariasis than flies were. Hemingway speculated that perhaps the resistant mosquitoes might also be less likely to transmit malaria.

“We need to check our facts,” Hemingway told New Scientist. “The research shows we may be able to live with resistance because there may be benefits.”

I don’t think so. As Chris Curtis, a researcher at the London School of Hygiene and Tropical Medicine, told New Scientist, Hemingway’s claims conflict with other studies. In fact given how widely DDT and other insecticides have been used and the large number of resistant mosquitoes, there is certainly no shortage of malaria cases. Even if there was some slight decline in any given mosquito’s ability to transmit malaria, that would seem to be overwhelmed by the sheer number of mosquitoes who survive once they become resistant.

Moreover, while the find is certainly intriguing for lymphatic filariasis — which infects 120 million people around the world and causes swelling in the limbs and genitals — there clearly is an environmental cost to pay for excessive spraying of DDT that is probably not worth it. The resistant mosquito strains emerged after unbelievably large quantities were sprayed largely for agricultural purposes rather than for malaria control.

Judicious application of organophosphate insecticides along with continued research on better treatments and possible cures or vaccinations for malaria makes a lot more sense.

Source:

Resistance is useful: Overuse of insecticides could be a blessing in disguise in fighting disease. Andy Coghlan, The New Scientist, October 25, 2000.

For many decades the most effective treatment for those infected with Malaria was chloroquine. But recently in many parts of the world a strain of malaria parasite that is resistant to chloroquine emerged. Some countries were forced to simply abandon chloroquine treatment.

Now researchers at the US Institute of Allegy and Infectious Diseases announced they found that the mutation of a single gene in the parasite is responsible for the emergence of chloroquine resistance. Formerly it was believed that a number of mutations spread over a number of genes was likely responsible.

If this result holds up, it should make it easier to potentially alter chloroquine in such a way as to evade the parasite’s new-found resistance and make chloroquine an effective treatment for malaria once again.

Source:

Malaria parasite gene breakthrough. The BBC, October 20, 2000.

The BBC reported last week that trials of a new vaccine for Malaria are now underway in the African nation of Gambia. The vaccine has already been tested in small trials held in Great Britain which were successful, but this will be the first widespread test of the vaccine in a country with a high prevalence of malaria.

There have been other vaccines to attack malaria, but they all relied on killing the malaria parasite before it infected the cells of the body. The new vaccine, however, incorporates portions of the malaria parasite’s DNA structure and is able to target the disease when it has already infected cells.

If the Gambia trial proves successful, the vaccine could become available for widespread inoculation within 5 to 10 years.

Source:

Malaria vaccine goes on trial. The BBC, September 18, 2000.

As if African nations didn’t have enough problems to worry about, a recent study published in the British medical magazine The Lancet confirms that HIV positive individuals are much more likely to contract Malaria than those not infected with the virus. After monitoring both HIV positive and non-HIV positive people in Uganda, researchers found the HIV-positive patients were almost twice as likely to be infected with malaria. This make sense since the diminished immune system of HIV patients makes them more susceptible to other diseases such as tuberculosis.

Given the continuing high rates of HIV infection Africa, which shows no hint of slowing down, this could be a huge public health disaster. Already about 2 million people worldwide die from malaria, and if HIV makes it easier for the malaria parasite to infect a person, those numbers could increase dramatically even with HIV treatment, further straining limited health care resources in African nations.

Source:

AIDS compound malaria problem. The BBC, September 22, 2000.

Too many children in Africa die from malaria, and so far nobody’s come up with much a solution. A recent study published in the Lancet, however, suggests that the answer might be as simple as giving mothers training on administering anti-malarial drugs to their young children.

In a study in Ethiopia, giving mothers chloroquine and showing them how to use it, reduced the rate of childhood death rates from 50 per 1,000 to 30 per 1,000 compared to a control group. In the group that was given chloroquine and training, only 19% of childhood deaths were attributable to malaria, whereas in a control group 57% of childhood deaths were attributable to malaria.

The researchers warned that some communities might not be as able to help themselves, but this certainly seems like an avenue of treatment that should be greatly expanded as soon as possible. If poor women in Ethiopia can successfully administer chloroquine to their children and thereby increase their odds of surviving, many families around the world should be able to benefit from this sort of intervention.

Source:

Mothers ‘could slash malaria deaths.’ The BBC, August 10, 2000.

    Malaria is still an enormous problem in many parts of the world. The World Health Organization estimates that every year there are 300 to 500 million cases of malaria worldwide and approximately 1 million deaths attributable to malaria (the disease is second only to tuberculosis in the toll it takes on humanity). Unfortunately the two main strategies for dealing with malaria, trying to kill mosquitoes with insecticides and treat the disease with medication, are both diminishing as pesticide-resistant mosquitoes and drug-resistant malaria strains are becoming more prevalent.

    Several scientists around the world are working on a more exotic approach — a strain of mosquito that is genetically modified to destroy the malaria plasmodium. Malaria has a complex series of vectors, and gets passed to human beings after the mosquito first picks up the disease by taking blood from another infected animal.

    Research into genetically modified mosquito strains has concentrated on adding genes that cause mosquitoes to have immune system reactions to the malaria bacteria so that the mosquitoes’ own natural defense mechanisms destroy the disease before the mosquito can pass it on to human beings. Working with the yellow-fever mosquito, researchers from MIchigan State University spliced a gene into insects that produced an antibody called defensin which was coded to go into action when the mosquito ingested blood. The genetically modified mosquitos had high levels of defensin in their blood stream for several weeks after feeding.

    But the obstacles to be overcome are still daunting. Before it was possible to genetically modify insects, researchers had long been trying to use traditional breeding methods to produce malaria-resistant mosquitoes. The problem they ran into was that the malaria-resistant mosquitoes were always less robust than the natural mosquitoes, meaning releasing even large numbers of them would be pointless since they would be quickly selected out of the breeding population.

    Dr. Jo Lines, a researcher in tropical medicine, outlined the problem for the BBC, saying “you would end up with insects that are highly inbred and devoid of genetic variability — the modified train of Aedes aegypti (yellow-fever mosquito) would come from a single egg, and that is bound to affect its competitiveness.”

    Not to mention the problems of how researchers would breed the hundreds of millions of mosquitoes needed to even have a shot at displacing traditional mosquitoes. Still, such research is certain to advance our understanding of both mosquitoes and malaria, even if it doesn’t lead to realistic near-term solutions.

Sources:

Further progress in war on malaria. The BBC, July 24, 2000.

Mosquito attacks its own problem. Jonathan Amos, The BBC, July 25, 2000.