The association of drinking water treatment and distribution network disturbances with Health Call Centre contacts for gastrointestinal illness symptoms
Journal article, 2013
There are relatively few studies on the association between disturbances in drinking water
services and symptoms of gastrointestinal (GI) illness. Health Call Centres data concerning
GI illness may be a useful source of information. This study investigates if there is an
increased frequency of contacts with the Health Call Centre (HCC) concerning gastrointestinal symptoms at times when there is a risk of impaired water quality due to disturbances at water works or the distribution network. The study was conducted in
Gothenburg, a Swedish city with 0.5 million inhabitants with a surface water source of
drinking water and two water works. All HCC contacts due to GI symptoms (diarrhoea,
vomiting or abdominal pain) were recorded for a three-year period, including also sex, age,
and geocoded location of residence. The number of contacts with the HCC in the affected
geographical areas were recorded during eight periods of disturbances in the water works
(e.g. short stops of chlorine dosing), six periods of large disturbances in the distribution
network (e.g. pumping station failure or pipe breaks with major consequences), and 818
pipe break and leak repairs over a three-year period. For each period of disturbance the
observed number of calls was compared with the number of calls during a control period
without disturbances in the same geographical area. In total about 55, 000 calls to the HCC
due to GI symptoms were recorded over the three-year period, 35 per 1000 inhabitants and
year, but much higher (>200) for children <3 yrs of age. There was no statistically significant
increase in calls due to GI illness during or after disturbances at the water works or in
the distribution network. Our results indicate that GI symptoms due to disturbances in
water works or the distribution network are rare. The number of serious failures was, however limited, and further studies are needed to be able to assess the risk of GI illness in
such cases. The technique of using geocoded HCC data together with geocoded records of
disturbances in the drinking water network was feasible.
Water works
Health Call Centres
Gastrointestinal
Drinking water quality
Distribution network