Thank you, Britta - really helpful.
So the inference is, a dirty community toilet is better for health than open defecation, in a densely populated slum at least.
That's certainly one part of the equation...the next factor to determine is how dense the population needs to be to reach tipping point.
Also, as mentioned by others, to what extent the open defecators bury their faeces, so that direct and indirect contact is lessened.
What is clear is that a clean community toilet would be significantly better than open defecation in this densely populated context.
Thanks again for sharing this useful and revealing study.
Susannah

Hi Susannah,

I am with interest looking for responses to your question as it is one we have thought about as well.
The one bit I can add to it empirically is a study we did on improving community toilets in slums of two Indian cities. here we find that caretakers change their behaviour when incentivised to keep the community toilet clean, which includes that they reduce free-riding, in a strategic manner. What this implies is that some who would have used the community toilet do not anymore (because for example the caretaker imposes fees) and we find that the increase in open defecation comes with an increase in health expenditures and reported morbidity. This would indicate that in this (high density) setting, the use of community toilet is better than OD.

Britta
Here a link to the paper in case of interest: ifs.org.uk/publications/15494

Dear Susannah,

Nice topic of discussion you brought up here, Working in the sector and living within the sub-saharan region where both practices are common, I have found that a lot of communities in rural areas prefer to defecate in the open rather than us a toilet for many reasons. Some of the notable ones are the issues of fecal exposure that come with the use of shared toilets, bush toilets being prone to collapse, cultural beliefs etc.

On the other hand and as Elizabeth has highlighted open-defecation risks exposing these communities (particularly Women) to increased sexual exploitation and personal safety and is a risk to public health (when populations are large), Though some will argue that these are not real risks as this can be attributed to the character of the community. Open defecation has been practiced for centuries and considered normal in some societies. Putting an end to it requires a sustained shift in the behaviour of practicing communities. Ending open defecation requires an ongoing investment in the construction, maintenance and use of toilets and other basic services like toilet paper for example. While open defecation will remain an issue to the dignity, health and well-being of people, especially of girls and women, the added challenge remains access to privacy during menstruation.

The use of shared sanitation on the other hand does reflect demand and this demand is growing within sub-saharan rural communities, however, failure to ensure there is the hygienic separation of human excreta from human contact is a huge challenge. Also, shared toilets do not necessarily guarantee security for users, there are still concerns about the security of users, especially at night. It is quite common that shared toilets are usually associated with several problems like poor management and exclusion. Poor health outcomes associated with shared sanitation are understood to be due to lack of cleanliness.

What is the calculation determining whether they are better off using shared chemical toilets, or the surrounding fields?

I hope this somewhat answers your question quoted here Susannah.. At least in my opinion, i find it is really a matter of context.

Regards,
Chaiwe

Hi Susannah,

I don't have a direct answer to your question but we do have a lengthy discussion thread on a related topic for the case of India here . The thread is called: "Pause before pushing more people to ODF (open defecation free)" and some arguments were made in the direction of "benefits of open defecation" which is I think what you're getting at. So you might enjoy reviewing that thread (it goes over 4 pages and was sometimes quite heated/controversial!)

I think apart from the factors that you mentioned, i.e. infection risk and social disgust, the other important factors would be privacy and safety, especially for women. Is it safer to use a cubicle toilet or an open field at night.

Regards,
Elisabeth

Hi all,
Can anyone enlighten me on this?
It seems to me there is a balance to be struck between the risks of sharing toilets with other households, and the risk to others of individually digging a little hole each time in the corner of a field, using leaves for wiping, and covering faeces with earth and clumps of turf.
And it strikes me that the tipping point might be to do with local population density, with stability of the community (ie how many strangers) another factor.
Is there any research to measure infection risks, and social disgust/disinclination?
I'm thinking of the vehicle and tent dwellers in and around this rural town in England. 
What is the calculation determining whether they are better off using shared chemical toilets, or the surrounding fields?
Thank you!
Susannah