In general, when in the mountains of Scotland above human habitation, the water is safe to drink, but you do have to think about where it is coming from and follow basic common sense rules.
Having said that water from streams and rivers is generally safe, you should always follow good hygiene rules and be aware of possible water-borne infections.
There are three ways by which water borne infections can be contracted:
The most common infections are listed below
These can be divided into three categories:
The most common example is E Coli, which is most likely to be contracted by swallowing water contaminated with sewerage.
Symptoms: rapid onset of diarrhoea without blood
Treatment: fast for 24 hours, drink clear fluids, water, tea without milk or commercial rehydration solutions
2 Infections which require treatment
If the symptoms persist after 24 hours then it may be more serious and require professional treatment. Examples include Shingella and Salmonella.
Symptoms: generally start 24 hours after exposure and may include fever, vomiting and diarrhoea with blood.
Treatment: visit your GP. Do not take anti-diarrheatics (for example, Imodium or Kaolin) because these may mask the symptoms. Do not cure the symptoms as this may make things worse.
NB: Do not drink from water sources that are shared by farm animals that are clearly concentrated into a small area.
3 Complex infections
More serious infections such as Leptospirosis, which has two forms: Weils Disease (a dangerous condition which results from infection carried in ratsí urine) and the Hardjo form transmitted to humans from cattle.
Symptoms: fever and flu-like condition
Treatment: full recovery is probable if a course of penicillin is taken in time but this depends upon immediate treatment. The time factor is crucial. Go straight to your GP, explaining the symptoms and possible source of infection from infected water. Ask for ten days of penicillin. Do not wait for a test as this wastes valuable time.
NB: a small number of cases of Leptospirosis infection have occurred on occasion around the central highlands of Scotland.
Common examples of these are Giardia and Amoebic Dysentery.
Symptoms: these start 24 hours after exposure and may include vomiting, diarrhoea with mucous and blood, eggy sulphurous burps and foul smelling gas.
Treatment: visit your GP. A stool test is recommended to get the diagnosis and treatment correct. However, the test may be negative in the case of Giardiasis.
NB: in Scotland it is extremely rare to contract Giardia or Amoebic infection from mountain streams or lochans (small lakes) and fresh-water such as this can usually be drunk untreated well away from any human habitation.
An example might be Hepatitis A. Viral infections are extremely rare. There is no specific treatment. Normally your own immune system will sort them out. It is possible to get free immunisation from your GP. A course of two injections is needed for ten years protection.
There are other possible types of hazard in water such as blue-green algae and pollution by chemicals.
Prevention is better than cure, so if the water looks suspect, for example, stagnant, discoloured, covered in a film of growth or has an oily surface, or looks otherwise polluted take the following advice:
Note: many small streams through areas of boggy ground or peat have an oily covering when slow running. This is not human pollution but natural chemical leaching from the peat. It is still best to avoid drinking it if possible.