Tuberculosis has featured strongly in TropIKA.net in the last couple of weeks. This is appropriate as World TB Day (24th March) will soon be with us. There are many issues that must be urgently addressed if further progress is to be made in controlling this disease, which kills over one and a half million people every year. There are particular concerns over the growing numbers of cases of drug-resistant forms of TB and new understanding [1] of the mechanism of action of two drugs active against multiple-drug resistant TB may help inform the search for the new drugs that are so desperately needed.

A neglected area of TB research has been diagnosis. Sputum microscopy – sometimes referred to as the “gold standard” for diagnosing TB – is time consuming, can only be conducted in the lab and often gives incorrect results. A rapid test that can be used on the front line is required. News of new funding [2] provided by the Gates Foundation to a non-profit group that focuses on this issue is much to be welcomed. Interestingly, a manufacturer of breath tests for disease diagnostics says it has developed a simple test that can diagnose active pulmonary TB within minutes – see TropIKA.net News in brief [3].

The importance of partnership is always stressed in TB control efforts. Important partners in the delivery of care include the private health care sector and it is disappointing that in India [4] many private practitioners do not apparently provide the recommended TB treatment DOTS (directly-observed therapy short course.)

Good news

Several recent TropIKA.net articles report good news concerning other infectious diseases of poverty. For example, a trial in India [5] found that a single transfusion of the drug amphotericin B, for which patients stayed in hospital for just 24 hours, was as effective in the treatment of visceral leishmaniasis (VL) as a course of treatment requiring a one-month hospital stay. This finding could have major implications; it would be possible to significantly increase the number of VL patients who receive treatment.

When new drugs are introduced they are not always popular with patients and this is bound to affect their compliance with the treatments they are prescribed – something that is not always taken into consideration when implementing new programmes. Much depends on the switch to artemisinin-combination therapy (ACT) as the standard treatment for uncomplicated malaria and it is reassuring to learn [6] that the introduction of the ACT Coartem in Dar es Salaam, Tanzania has met with a positive reception from the local community, including mothers whose children have been treated for malaria.

A TropIKA “Research in brief” article [7] includes further welcome news: a new insecticide could be in prospect for mosquito control, research at the “basic” level could lead on to the development of treatments for cholera and for the kinetoplastid diseases, and a drug already in use in veterinary medicine could be developed as a new treatment for onchocerciasis.

Looking to the future, research into sleeping sickness (human African trypanosomiasis) will be boosted by new Gates funding, and the Australian government has made new grants to researchers working on malaria [8]. In both these cases the research will be based in institutions located in developed countries, but there is a pressing need for more research to be done in disease-endemic countries themselves and for it to be conducted by nationals of those countries. This was the theme of the African Expert Meeting on Pharmaceutical Innovation in Africa, held in Pretoria, South Africa [9], where a call was made for support to enable the development and production of medicines, “in Africa, by Africans”. The registration in African countries of new drugs shown to be effective against the infectious diseases of poverty was also discussed at this meeting [10]. Robust registration procedures are of course necessary but they must not lead to unnecessary delays in bringing the fruits of scientific research to those who most need them.

An important part of TropIKA.net is our Profiles section in which Tatum Anderson interviews key figures working against the infectious diseases of poverty. We are delighted that our latest interviewee is Dr Awa-Marie Coll-Seck executive director of the Rollback Malaria Partnership (RBM). She plays a crucial role in coordinating the activities of the myriad of organizations now involved in international efforts to improve malaria control. One of the many new malaria initiatives is the Affordable Medicines Facility for malaria (AMFm). There is currently much debate, for example in a recent PLoS Medicine article, as to the merits of this scheme and how it might best be implemented.

Another recent Profile interviewee, Brian Greenwood, is probably best known for his work against malaria but in his long career in tropical medicine he has also focused on other diseases, among them is meningitis. We report on the launch of the African Meningococcal Carriage Consortium (MenAfriCar), to be headed by Professor Greenwood, which will make a concerted effort to understand the spread of meningococcal meningitis in Africa.

We also report good news on another disease that is predominantly an African problem – onchocerciasis (river blindness). Mass administration of the drug ivermectin kills the larvae of the parasite responsible but not the adult; repeat treatments (once or twice a year) are therefore given. It has been widely believed that communities living in areas endemic for the disease would need to be given these treatments indefinitely. However, a study in Mali and Senegal found that, after 15-17 years of mass drug administration with ivermectin, only a few people were still infected and treatment could safely be stopped. Ivermectin is not, however, an ideal drug. Many patients find it extremely unpleasant to take and parasite resistance to the drug has been reported. Research to find new ways to control river blindness that do not depend on ivermectin therefore remains important – see TropIKA.net news story on the latest meeting of the SCOOTT Consortium (Sustainable Control of Onchocerciasis today and Tomorrow).

Amongst the other good news has been the announcement by the International Trachoma Initiative that three more countries (Ghana, Mexico and Saudi Arabia) have now met the criteria for elimination of trachoma as a public health problem. It is unusual to see a low-, a medium- and a high-income country mentioned together for the same achievement! Tropical diseases can indeed afflict both rich and poor but it those who live in poverty who are the most vulnerable.

Many of the countries where dengue fever is a problem are emerging economies in Latin America and Southeast Asia. The economic impact of the disease is therefore considerable. Probably the most comprehensive study to date seeking to quantify this impact has just been published. Infectious diseases that affect poor people are by and large neglected, but with increasing wealth in dengue-afflicted nations, perhaps the economic imperative will lead to an expansion of efforts to develop a vaccine and a treatment for this increasingly common disease.

The diagnosis of the infectious diseases of poverty is itself a neglected issue. When advances are made in the treatment of a disease, rapid and reliable diagnosis becomes even more important, as was discussed in the case of malaria in a recent BMJ article.

Two initiatives to address the neglect of diagnosis have made an appearance in TropIKA.net during the last few days. The African Network for Drugs and Diagnostics Innovation (ANDi) has announced that it will present its strategy and business plan in October, and the TropIKA.net blog links to an interview with Joseph Ndung’u of the Foundation for Innovative New Diagnostics (FIND) about the search for a new diagnostic test for trypanosomiasis (sleeping sickness).

- For more on new developments in diagnosis, see also a recent article in TDR News.

Paul Chinnock
Editor-in-Chief, TropIKA.net

Let’s start with the good news on research targeting the infectious diseases of poverty. There has been a lot of it, as featured on TropIKA.net in the last couple of weeks, from the molecular to the public health level.

A new Wellcome Trust initiative will boost research capacity in Africa, a gene map has been constructed for the parasite that causes schistosomiasis, opening up new avenues for research, and a potential new rabies vaccine has given promising results in mice. A trial has begun of a new drug for river blindness, and a trial of an improved treatment for sleeping sickness has been completed with encouraging results.

Meanwhile the US government has made it clear that, following the broadening of its policies on global health, it will provide new support for the control of neglected tropical diseases (NTDs). Unfortunately, only seven infections from the long list of NTDs have been targeted by the US at this stage. (Leishmaniasis, Chagas disease and dengue fever are examples of the NTDs not yet included.) Nevertheless, this is still an exciting initiative and other countries in the North might now be expected to follow the US lead.

These examples of positive developments contrast with the news from Kenya that over 70% of malaria patients there are given the wrong malaria treatment; they receive older ineffective antimalarials and not artemisinin combination therapy (ACT), the internationally recommended treatment. This finding (from the 2007 Kenya Malaria Indicator Survey, the full report of which is not yet freely available) supports observations in many African countries that ACTs are only getting through to a minority of those who need them.

Coincidentally, within the same month that the Kenyan report was published, the 250 millionth dose of the most widely available ACT, Coartem, was delivered. (TropIKA.net marked the event with an interview with the head of marketing and access for the malaria initiative at Coartem’s manufacturer, Novartis.) Progress is therefore being made but there is a long way to go.

An example of what a malaria control programme can achieve comes from a study conducted in the tiny island of Bioko, Equatorial Guinea where, within four years of the introduction of a multi-intervention strategy, prevalence in children dropped from 42% to 18% and all-cause child mortality fell by two-thirds. Such research demonstrates what is possible, but the challenge remains of bringing the potential benefits of research evidence to entire populations in disease-endemic countries.

“Evidence into policy” is the first part of this challenge. A recent article in Lancet Infectious Diseases noted that, while national guidelines in most Africa countries now list ACTs as the recommended first-line treatment for malaria, the majority of these guidelines have not changed as regards second-line treatment, for which they still recommend oral quinine monotherapy. This is despite the fact that the World Health Organization has stated that ACTs should also be the mainstay of second-line treatment.

But “policy into practice” is the next part of the challenge. In the case of ACTs, practitioners cannot give them to patients, as either first- or second-line treatment, if the drugs are not actually available. I am reminded of the British civil servant who said, after a new directive from his political masters, “If the policy is that pigs will fly, whose fault is it when they don’t?” (Sometimes those who write policy documents and guidelines need to distinguish between aspirational and operational targets.)

Two other research articles highlighted on TropIKA.net have implications for policy making in child health. A systematic review concludes that WHO is wrong in its recommendation that iron supplements should not be given to children under two years, if they live in malarious regions. In contrast, a South African study provides evidence to support the WHO position that children known to be HIV-infected shown not be given BCG, even in countries where the risk of TB infection is high. The interpretation of the evidence in such studies is, however, always likely to be controversial. Putting evidence into policy and policy into practice both present formidable obstacles.

Paul Chinnock
Editor-in-Chief, TropIKA.net

The infectious disease of poverty that has been most in the news over the last few days is tuberculosis. Its high profile during this period has been largely due to World Tuberculosis Day and to the publication of the latest WHO annual report on the disease.

While it is easy to be cynical about the increasing number of annual days focussing on particular health or social issues, World TB Day does succeed in getting TB into the media, which can often be difficult, even for charities paying for fund-raising advertisements. In the TropIKA.net blog, we reported on the charity which was told by a TV company that its film about Buruli ulcer was too shocking to show during the daytime. This was despite the very restrained and tasteful nature of the film, in which the ulcers themselves were carefully blurred. Perhaps this is one reason why most infectious diseases of poverty are so severely neglected – they are too upsetting for us even to think about. The Second International Conference on Buruli Ulcer is incidentally now taking place in Benin.

Sleeping sickness (human African trypanosomiasis) is another much neglected disease. TropIKA.net has taken a look at research articles published on the disease within the last few months and we have attempted to sum up the key developments in a review article.

A non-government organization specialising in the leading infectious cause of blindness, trachoma, has announced that it is merging with a larger NGO. Should there be organizations that focus on just one disease or does this promote a ‘vertical’ approach to health care? And does it help when such bodies merge; does it make bureaucracy worse or reduce it? It would be interesting to have the opinions of TropIKA.net readers on these questions. Each of our articles and blogs has a facility for comment, so please do get in touch. We have had some good feedback on a number of our articles lately - see the following examples: 1, 2, 3.

But I shall finish this latest Editor’s choice by returning to World TB Day. The Stop TB Partnership has this year stressed the economic benefits of TB control. Dr Marcos Espinal, Executive Secretary of the Partnership said, “Most highly affected countries could gain nine times or more their investments in TB control”. In the current economic climate it is indeed important to emphasise such points to policy makers, with regard not just to TB but all the infectious diseases that blight the lives and reduce the productivity of the world’s poorest people. However, we must keep in mind the humanitarian as well as the economic imperative. It is unfair and unjust that millions of people continue to suffer from diseases like trachoma, Buruli ulcer and trypanosomiasis. Regardless of the financial costs and benefits, action against all these diseases must now be stepped up.

Paul Chinnock
Editor-in-Chief, TropIKA.net

Examples of the innovative use of new technology to help to control the infectious diseases of poverty are often featured on TropIKA.net. The mobile phone is a piece of new technology that has been adopted enthusiastically across the developing world and the ready availability of these now ubiquitous devices has been put to good use by a team of software developers. An application which can be downloaded to mobiles has been used within a successful campaign to bring under control Kenya’s first polio outbreak for 21 years. See Mobile phone technology helps contain disease outbreak.

Of the diseases on the TropIKA.net priority list, it is tuberculosis that has been most in the headlines over the last few weeks. We have summed up some of the most important developments in our article, Tuberculosis profile rising. Malaria also receives more attention from the international media than was previously the case. The World Malaria Report for 2008 was reported by many newspapers worldwide and (as I write this latest Editor’s Choice column) news is coming in of agreement at the UN for major new funding for malaria control.

However, the excitement over new developments and innovations should not mean that the lessons of history are forgotten – see Malaria control: ‘faulty intelligence’ led to mistakes.

One such lesson is that gains made in infectious disease control so easily can be lost. Having brought rabies under control for several years, China now seems to be facing a resurgence of the disease – see Renewed rabies vigilance needed in China.

The increasing number of dengue fever cases is a major problem affecting a much wider area. The situation in the Asia-Pacific region and also Latin America is of increasing concern. One recent research article that has been the subject of a commentary on TropIKA.net is a systematic review examining dengue outbreak prediction and detection tools – see What does dengue disease surveillance contribute to predicting and detecting outbreaks and describing trends?

As well as commenting on recently published research article, TropIKA.net highlights review articles of particular importance. Sleeping sickness and Chagas’ disease are often featured on our knowledge platform and a recent review is relevant to both of them – see Trypanosomiasis vector control in Africa and Latin America. An infectious disease that also takes a major toll but which is often forgotten and has not previously appeared on TropIKA.net is bacterial sepsis – see Strategies to Reduce Mortality from Bacterial Sepsis in Adults in Developing Countries.

>blog. Responses to what our bloggers are saying are always welcome.

Paul Chinnock
Editor-in-Chief, TropIKA.net