What is Protozoa?
Protozoa (or Protists) are single celled eukaryotic organisms which exhibit animal like characteristics like predation. Some of these, like Giardia and Cryptosporidium (various species) can cause parasitic disease in humans.
Which pathogenic protozoa can be found in water supplies?
Giardia and Cryptosporidium are very common in New Zealand.
Giardia
Is carried by birds and other animals. It can cause a nasty infection, characterised by symptoms like violent diarrhoea, excess gas, stomach or abdominal cramps, upset stomach, and nausea. Worse still it can last for 2-6weeks and can recur.
It can also be passed from person to person via the fecal-oral route.
When outside of a host, these form cysts which are very hardy and can resist even chlorine treatment.
It is also possible if you did get this from your water supply to continue to reinfect yourself if the water is not treated
New Zealand has a higher rate of giardiasis infections than other parts of the developed world, at more than 5x the infection rate per 100,000 people than the UK.
Cryptosporidium
Is carried by birds and other animals. It can cause watery diarrhea, stomach cramps or pain, dehydration, nausea, vomiting, fever, weight loss.
It can also be passed from person to person via the fecal-oral route.
When outside of a host, these form cysts which are very hardy and can resist even chlorine treatment.
It is also possible, if you did get this from your water supply to continue to reinfect yourself if the water is not treated.
New Zealand has a higher rate of Cryptosporidium infections than other parts of the developed world, the annual notification rate between 1997-2006 averaged 22.0 cases per 100 000, much higher than Australia (15.8) UK (8.5), USA (3.0) and Germany (1.6).