Download How water quality can vary through the year?

Private Water Supplies
Dr Simon Padfield
Consultant in Communicable Disease Control
North Yorkshire and Humber Health Protection Unit
What does the health protection
agency do?
• disease surveillance
• investigation of individual cases of illness
• outbreak management
What are the health issues in relation
to water?
• infectious disease
• outbreaks
• lead
• other chemical/mineral contamination
Some common types of bacteria in unwholesome water
Campylobacter:
Campylobacter is the commonest reported bacterial cause of infectious intestinal
disease in England and Wales. Symptoms include diarrhoea or bloody diarrhoea,
vomiting, abdominal pain and fever. with an average duration of two to five days but
prolonged illness and relapse can occur in adults. Poultry and cattle are the most
common reservoirs of infection for the organism although puppies, kittens, other pets,
rodents, sheep, pigs and birds may also be sources of infection in humans.
Cryptosporidium:
Cryptosporidium is a parasite that can cause symptoms of watery diarrhoea, abdominal
pain, low grade fever, nausea and vomiting. Symptoms can range from mild to severe
and usually last for up to 2 weeks, sometimes longer, with about one third of patients
experiencing relapse. There is no specific treatment. Most people recover but in some
patients with immune system conditions it can be severe and sometimes life threatening.
All ages can be affected but more cases are reported among children, especially children
under the age of five.
Escherichia coli or ‘E.coli’ including ‘E.coli O157’:
E. coli is a bacterium that lives in the intestines as part of the normal gut bacteria of both
humans and animals. Some strains can produce a harmful toxin, sometimes these
bacteria are referred to as ‘E.coli O157’ or VTEC O157. In people, VTEC O157 can
cause a range of symptoms, from mild diarrhoea to severe abdominal pain and bloody
diarrhoea. In a small proportion of patients (2-7%, and mainly children), it can cause
haemolytic uraemic syndrome (HUS), which is a serious condition resulting in kidney
failure. Cattle are thought to be the main reservoir of infection, but the bacterium has
also been isolated in many other species including sheep, goats, pigs, horses, donkeys,
farm dogs, llamas, alpacas and wild rabbits.
Outbreak linked to a private water
supply, Lothersdale, North Yorkshire,
2008
• 60 cases of gastrointestinal illness
• 15 E.coli O157, 16 campylobacter, 2 both
• Haemolytic Uraemic Syndrome
Is your water always safe to drink?
How the quality of untreated water from a private water supply can vary
through the year
700
cfu/100mls
600
500
2010
400
300
200
100
Total Coliforms
Escherichia Coliforms
0
700
cfu/100mls
600
500
2011
400
300
200
100
0
Total Coliforms
Escherichia Coliforms
Who is at risk?
• you? (now or in the future?)
what about immunity/tolerance?
• very young children and babies
• the elderly
• visitors
• people with specific underlying health conditions
(immunodeficiency, cancer chemotherapy, high dose
steroid treatment, HIV)