The statistics say it all: 70% of the transmission of infectious diseases is focused in and around the house. Including malaria, where the key vectors in Africa are almost exclusively feeding indoors and at night. The forum on MalariaWorld that discussed this issue was very well read (more than 1000 views), and although comments were limited, it was enough to move forward with the idea...
How can we make houses less prone to mosquito invasion and reduce transmission?
To this effect, a workshop was organised by Derek Charlwood and Erling Moller Pedersen in Copenhagen last week, attended by Jakob Knudsen, Peter Williams, Steve Lindsay, Petter Brandberg, and myself. The goal was broader, by not focusing only on malaria, but health in general. Vector-borne diseases, (chronic) respiratory infections, and diarrhoeal diseases - can we design houses that reduce or even virtually eliminate these health threats?
For three days, we reviewed the historical evidence that is there, examples of where house improvement really made a difference in disease. Screening of porches in the southern USA made a huge difference in malaria transmission, concrete floors can substantially reduce diarrhoeal diseases, and improved airflow can have a massive impact on smoke-related disease and TB.
We then detailed as much as possible the issues associated with health and the housing environment (see image) and based on that designed what could be a 'disease-proof' house. A house that will be constructed in Mozambique, using locally available materials, over the next few months.
We acknowledged the fact that the complexity of this issue merits the involvement of other disciplines (like anthropology) that will be included in future endeavours. Preferably, a house that is both healthy and acceptable, desirable, and a 'wonna-have' in local communities will emerge from this. The health gains can, no doubt, be phenomenal, if this can be accomplished.
Our next step will be to draft a funding proposal to move forward with the ideas in South America, Africa, and South-East Asia. We aim to study local house designs and monitor climatic variables therein, to see why people build the houses the way they do, and how comfortable these are in terms of indoor climate (temperature, humidity, airflow). Next, we aim to study the behaviour of vectors in and around houses in much greater detail, which is the key to develop changes in house structure that can interfere with this process (e.g. turn the house into a trap). The same applies to the 'behaviour' of (airborne) pathogens. Such interventions can then be field-tested and reviewed in terms of acceptability and cost, and improved where needed.
We invite anyone interested in this subject to comment and suggest additional ideas for this project.
We acknowledge support from the Bill and Melinda Gates Foundation to organise this workshop.