Swimming-related illnesses
Overview
Monitoring of water quality by Beachwatch shows that water quality is safe for swimming at most of Sydney's beaches, virtually all of the time. However after heavy rain, pollution from stormwater and sewage overflows can make beaches unsuitable for swimming for 24 hours at ocean beaches and for at least three days at harbour or estuarine swimming areas.
In polluted waters, swimmers may be exposed to pathogens, which can easily enter the ears, eyes, nose and mouth. The skin is also directly exposed to infectious agents and chemicals through swimming, playing or working in polluted waters.
This exposure can lead to a variety of health problems including gastroenteritis, flu-like illnesses, dermatitis, ear, nose and throat infections, sinusitis and deep tissue or blood infections through open wounds. The number of pathogens required to cause infections varies widely between micro-organisms and the general health of an individual. Children, the elderly and people with weakened immune systems appear to be at greater risk. Visitors without prior immunity may also be at higher risk than the local population.
Pathogens
Pathogens are organisms that can cause disease in humans. The most common types of waterborne pathogens are:
- Enteric Bacteria: single-celled organisms that live in the intestinal tracts of all warm blooded animals. Several groups of these bacteria are pathogenic, including Camplobacter, Salmonella, Pseudomonas and Shigella
- Viruses: genetic material surrounded by a protein shell. These are a common cause of swimming-related illnesses and include Rotaviruses, Adenoviruses, Noroviruses and Hepatitis
- Protozoa: live in water as resilient dormant cysts and once ingested, can live as parasites in humans and animals. Of the 35,000 known species of protozoans, 30% of these are pathogenic and include Giardia and Cryptosporidium
- Worms which can cause vomiting, coughing, chest pain, fever and gastroenteritis.
Swimming-related pathogens and illnesses
Pathogen | Illness |
Enteric Bacteria |
Camplobacter | Gastroenteritis |
Salmonella | Gastroenteritis |
Pseudomonas | Skin and ear infections |
Shigella | Bacillary dysentery |
Viruses |
Rotaviruses | Diarrhoea, vomiting |
Adenoviruses | Respiratory disease, gastroenteritis |
Noroviruses | Diarrhoea, vomiting |
Hepatitis | Hepatitis A and E |
Parasitic Protozoa |
Cryptosporidium | Diarrhoea |
Giardia | Diarrhoea |
Page last updated: 26 February 2011
