org355: Guinea Worm | LSHTM Moodle

From Nature

Dracunculiasis, to me, is the most interesting infectious disease out there. Caused by the guinea worm, it is a target of an eradiction effort, and may become the second disease ever eradicated among humans.

The International Task Force for Disease Eradication currently has eight diseases identified as potentially eradicable. In addition to Guinea worm, these are poliomyelitis, mumps, rubella, lymphatic filariasis, cysticercosis, measles and yaws.

1. What are the characteristics of diseases which make them potentially eradicable?

2. Check out the graph 'On the Way Out'. Explain why the Y axis is presented this way.

3. How would you determine that the incidence of a disease is 0?

4. How would you track the incidence or prevalence of infection among animal hosts?

Re: Guinea Worm

by | DEANNA EARLE - Saturday, 19 February 2022, 2:20 AM

Hello,

1. For a disease to be potentially eradicable, it has to have an easily-identified source/cause of infection and the disease has to impact enough people for researchers focus on it (although there are a number of researchers that focus on Neglected Tropical Diseases). For diseases for which a vaccine has been developed - and is effective - there has to be a high enough vaccination rate so that herd immunity is achieved.

2. The Y axis is presented this way because, compared to a traditional scale, the percentage change is more clear to see.

3. You would determine that the incidence of a disease is 0 if there are not any cases for x years, with "x" being a pre-determined number.

4. To track the incidence or prevalence of infection among animal hosts: animals can be tagged and tracked or a set number of animals can be trapped and tested periodically.

Re: Guinea Worm

by | Sujit Rathod - Sunday, 20 February 2022, 3:27 AM

Hi Deanna, thanks for posting.

For #1, it's worth noting that there is no vaccine or treatment for guinea worm. The eradication programme is heavily reliant on behaviour change. Which makes its success over time quite remarkable.