Utilizing the Sun While We Wait for Pipes

One of, if not the major issue surrounding infectious diseases in Africa is the lack of regular access to clean water. In countries like Ethiopia, it is said that around 78% of the population do not have access to clean water, which is equivalent to about 56 million people – in one country alone.
In such drastic circumstances where so many people are going without water and investment in infrastructure is for the most part inadequately financed or outright neglected, innovative measures need to be taken to provide immediate, if only short-term supplies of water.

The concept of Solar Disinfection involves the exposure of contaminated drinking water in transparent bottles to strong, direct sunlight for significant periods (usually not less than six hours) to allow for the thermal and optical inactivation of microorganisms present in the water. – This can be as simple as placing plastic bottles filled with water on a roof for an entire day, allowing sunlight to kill the microorganisms present in the water.

A small study conducted in both Spain and Bolivia, investigated the impact of solar disinfection on four different types of disease causing bacteria normally present in contaminated water, one of them being Entero-pathogenic Escherichia coli (EPEC), which is a major cause of diarrhea, especially in infants. Results showed that after only 90 minutes of exposure to approximately 1,050 Watts per square metre of sunlight, EPEC fell below the limit of detection. In addition to this, all the bacteria investigated in the study showed no signs of re-growth after a full 48 hours.

This process of water decontamination is in no way a new concept to Africa, and continues to be carried out in many places – Sierra Leone being a most recent example. Yet scientific evidence that the process is actually effective is always a good thing, as this proves that it is an area warranting further investigation, and should therefore attract funding for larger scale projects – as the impact of this technique on many other disease causing agents remains to be examined.

However, despite the immediate importance and practicality of such techniques, widespread access to pipe-borne water must remain the major long-term priority throughout Africa, in order to move a step closer to the eradication of the many infectious diseases that are already a thing of the past in most developed countries.