Eighty-five per cent of cases involve infection with parasitic worms

CDC

[NAIROBI] Africa's neglected tropical diseases (NTD) burden is more than double the burden of tuberculosis and almost half that of malaria, a new analysis has found — raising questions about funding priorities.

More than 500 million people in Sub-Saharan Africa suffer from seven key neglected infections, according to researchers writing in PLoS Neglected Tropical Diseases last week (25 August).

They reviewed available data from 2003–2008 using sources including online database PubMed and information published by the WHO. Over the last decade, they say, a wealth of new information has been generated through geographic information systems and remote sensing — shedding new light on the true burden of neglected tropical diseases.

"We can no longer talk about the 'big three' diseases ... there is a fourth leg to this table that must be dealt with," Peter Hotez, co-author of the analysis and president of the US-based Sabin Vaccine Institute, told SciDev.Net.

As a result of their findings, the authors are calling for neglected diseases to be given a status equivalent to that commanded by these three — TB, malaria and HIV/AIDS.

The seven most common neglected tropical diseases in the region are hookworm, ascariasis, trichiuriasis, schistosomiasis (snail fever), lymphatic filariasis (elephantiasis), onchocerciasis (river blindness) and trachoma.

Eighty-five per cent of the cases recorded in the analysis involved helminth (parasitic worm) infections — despite the fact, say the authors, that there are effective treatments available.

"For US$200–$400 million a year over five years, we could significantly reduce the burden of helminth infections and other NTDs from much of Sub-Saharan Africa," says Hotez. "That's a minimal investment with maximum returns."

The research highlighted Nigeria and the Democratic Republic of Congo as the greatest reservoirs of the diseases — together, they account for one-third of all reported cases in Sub-Saharan Africa.

A targeted approach for these two countries could have a substantial impact on the total African disease burden, says Hotez.

The analysis also revealed that there is little or no data on an array of other important neglected diseases: "Thus, the overall burden of Africa's NTDs may be severely underestimated," the authors write.

They call for a full analysis of all such diseases on the continent.

Link to full article in PLoS Neglected Tropical Disease