Humanity Moves Closer to Eradicating Three More Diseases

The World Health Organisation (WHO) objective is to eradicate polio by 2018 and yaws by 2020To date, smallpox is the only infectious disease that has been totally eradicated from the face of the earth; the last person affected was a 23-year-old Somalian Ali Maow Maalin, who was cured in 1977. Massive vaccination campaigns delivered the world from a disease that once killed 35% of its victims and left many others blind or scarred for life. And with the eradication of smallpox came the hope that it would be possible to eradicate other diseases, such as poliomyelitis, dracunculiasis, and yaws.

Poliomielitis is a viral disease that causes paralysis of one or more limbs and in severe cases affects the respiratory musculature. In 2013, only 416 cases were recorded worldwide. The annual figure just two years earlier was 650 cases, and in the 1990s, over 350,000 cases were recorded every year. Despite this spectacular progress, three countries are finding it difficult to completely eradicate the disease: some areas of Pakistan and Afghanistan are inaccessible to vaccination teams due to political conflicts, and in Nigeria rumours suggesting that the vaccine has adverse effects have compromised its acceptance. Until transmission of the virus is interrupted in these three countries, the risk of new imported cases of polio elsewhere will persist, and such cases have been reported in Somalia in the last two years.

The World Health Organisation (WHO) objective is to eradicate polio by 2018 and yaws by 2020. Yaws is a bacterial disease closely related to syphilis that results in painful sores which can spread into the bones, causing inflammation and deformation. The members of a team of researchers from ISGlobal have worked to finalise the toolkit that will be used to eradicate this disease for once and for all: a diagnostic test based on a drop of blood used to confirm the presence of the infection and a single antibiotic tablet that can effect a complete cure.

When there are no more cases of a disease in an specific geographic area, we say the disease has been eliminated. Eradication, on the other hand, refers to the interruption of transmission of the disease worldwideEfforts are also underway to eradicate dracunculiasis, a condition caused by the guinea worm, a parasite resembling a piece of string that can grow up to a metre long. People living in remote villages are still infected by this parasite when they drink contaminated water containing the larvae, and simple filtration of the water could prevent the disease.

Polio, yaws, and dracunculiasis could soon join smallpox on the list of eradicated diseases. Eradication is a step beyond elimination. When there are no more cases of a disease in an specific geographic area, we say the disease has been eliminated. Eradication, on the other hand, refers to the interruption of transmission of the disease worldwide. An eradication programme involves certain basic elements: the need to intervene in all regions where the disease is found, no matter how remote or inaccessible the area, and the need to keep the final objective in sight until the last person on the planet with the disease has been cured. Thanks to the increase in resources and new medical tools, new possibilities will open up in the coming years for eradicating other diseases that still cause serious health problems across very large areas of the world, including malaria, the next big challenge that must be tackled in the field of global health.