Table of ContentsView AllTable of ContentsSwimmer’s ItchSeabather’s EruptionBikini Bottom Folliculitis
Table of ContentsView All
View All
Table of Contents
Swimmer’s Itch
Seabather’s Eruption
Bikini Bottom Folliculitis
An ocean rash is not uncommon after swimming, surfing, or diving in open water. Parasites that causeswimmer’s itchare one of the most common reasons for this type of irritating rash. However, otherinsect bitesas well asbacteriamay also be to blame.
Itchy rashesthat develop after swimming in the ocean are usually easily treatable and preventable.
This article explains why you might develop a rash after swimming in the ocean and what you can do about it.
Merlas / iStock / Getty Images
Swimmer’s itch, also known ascercarial dermatitis, occurs when people swim in water contaminated with parasites calledschistosomes.It often occurs in fresh water but it can also occur in salty ocean water.
These animals serve as the hosts for the life cycle of the schistosome, although the parasite will enter the human skin, causing an irritating or allergic rash as it dies. Not all species of schistosomes are the same; some cause more dangerous diseases in other parts of the world.
In some cases, people who develop swimmer’s itch aren’t swimming. The condition has been diagnosed in field workers across Asia who work in rice paddies, also an aquatic environment.
What Is Schistosomiasis Disease?
Treatment and Prevention
The rash from swimmer’s itch usually goes away after a week, with or without treatment. The schistosome doesn’t cause a parasitic infection in humans—it dies in the skin, but still causes a skin rash. Swimmer’s itch isn’t contagious from person to person.
The rash is best treated withtopical corticosteroidcreams and oralantihistamines. Still, swimmer’s itch will occasionally need treatment with oral or injected corticosteroids. Your healthcare provider may prescribeantibioticsif a secondary bacterial infection is present.
Swimmer’s itch can occur in waters throughout the United States. There isn’t a way to prevent getting swimmer’s itch other than avoiding contact with contaminated lakes and rivers. Hot temperatures increase the risk of getting the infection.
Common Recreational Water Illnesses and How to Prevent Them
Symptoms often start while the person is still in the ocean but may occur many hours after exposure. Occasionally, in addition to the itchy skin rash, a person may experience systemic symptoms from the toxin, such as fever, chills, nausea, vomiting, headache, and diarrhea.
The larvae that cause seabather’s eruption are sometimes called sea lice, but sea lice refers to other aquatic species that affect fish and other marine life rather than people.
There’s a delay in how larvae release the antivenom that causes a skin rash, so seabather’s eruption can last for up to several weeks.Treatment includes the use oftopical corticosteroid creams,oral antihistamines, and, occasionally,oral or injected corticosteroids.
Rubbing the skin makes the symptoms worse, as the larvae release a toxin into the skin as a result of pressure or friction; scratching can lead tobacterial infections. Taking off the contaminated swimwear and washing it before reuse may prevent additional rash and symptoms from developing.
Microscopic organisms can cause itchy rashes after swimming in salt water (the ocean) or fresh water (lakes, ponds, rivers, and streams). Seabather’s eruption most commonly occurs along the East Coast of the United States.
Wearing wet bathing suit bottoms for long periods can result in deep bacterialfolliculitisinfections withStreptococcus,Staphylococcus aureus,orP. aeruginosa.The rash is common on the buttocks and armpits.
P. aeruginosais found in both swimming pools and hot tubs, with some evidence that about two-thirds of them have the bacteria present at any given time.Folliculitis infections can affect multiple people when exposed at public facilities.
Most cases of bikini bottom folliculitis will go away on their own in a week or two. If not, bikini bottom infection is treated with oral antibiotics. The infection may linger in people diagnosed with diabetes and other chronic health issues.
Some studies find thatP. aeruginosabacteria found in swimming pools can be resistant to antibiotic treatment. Ciprofloxacin, a fluoroquinolone, is often effective.
Summary
Ocean rashes, as well as those acquired in freshwater lakes and swimming pools, are symptoms of infection that can arise from different causes, including bacteria, parasites, and larva.
These different causes mean that the appropriate treatments are different, too. Some conditions, like bikini bottom folliculitis, will go away on their own with most people. Others require antibiotic treatment and disinfection of swimming and diving gear.
Talk with your healthcare provider if you have questions about these rashes or experience ocean rash symptoms.
Can Probiotics Treat or Prevent Bacterial Infections?
10 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Schols R, Smitz N, Vanderheyden A, Huyse T.Expanding the swimmer’s itch pool of the Benelux: a first record of the neurotropic Trichobilharzia regenti and potential link to human infection.Parasit Vectors. 2024 Mar 13;17(1):126. doi:10.1186/s13071-024-06218-4.Tracz ES, Al-jubury A, Buchmann K, Bygum A.Outbreak of swimmer’s itch in Denmark.Acta Derm Venereol. 2019;99(12):1116-20. doi:10.2340/00015555-3309Loker ES, DeJong RJ, Brant SV.Scratching the Itch: Updated Perspectives on the Schistosomes Responsible for Swimmer’s Itch around the World.Pathogens. 2022 May 16;11(5):587. doi: 10.3390/pathogens11050587.Blankespoor CL, Blankespoor HD, DeJong RJ.Swimmer’s itch control: Timely waterfowl brood relocation significantly reduces an avian schistosome population and human cases on recreational lakes.PLoS One. 2024 Feb 15;19(2):e0288948. doi: 10.1371/journal.pone.0288948.Sridhar SC, Deo SC.Marine and other aquatic dermatoses.Indian Journal of Dermatology. 2017;62(1):66-78. doi:10.4103/0019-5154.198052National Capital Poison Center.Seabather’s Eruption Symptoms and Treatment.Chang T, Hunt BPV, Hirai J, Suttle CA.Divergent RNA viruses infecting sea lice, major ectoparasites of fish.PLoS Pathog. 2023 Jun 22;19(6):e1011386. doi:10.1371/journal.ppat.1011386.Thornton NJ, Garcia B, Hoyer P.Aquatic Antagonists: Marine Rashes (Seabather’s Eruption and Diver’s Dermatitis).Cutis. 2022 May;109(5):255-260. doi: 10.12788/cutis.0522.Khodaee M, Edelman GT, Spittler J, et al.Medical care for swimmers.Sports Med Open.2015;2:27. doi:10.1186/s40798-016-0051-2Jacob JS, Tschen J.Hot Tub-Associated Pseudomonas Folliculitis: A Case Report and Review of Host Risk Factors.Cureus. 2020 Sep 23;12(9):e10623. doi: 10.7759/cureus.10623.
10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Schols R, Smitz N, Vanderheyden A, Huyse T.Expanding the swimmer’s itch pool of the Benelux: a first record of the neurotropic Trichobilharzia regenti and potential link to human infection.Parasit Vectors. 2024 Mar 13;17(1):126. doi:10.1186/s13071-024-06218-4.Tracz ES, Al-jubury A, Buchmann K, Bygum A.Outbreak of swimmer’s itch in Denmark.Acta Derm Venereol. 2019;99(12):1116-20. doi:10.2340/00015555-3309Loker ES, DeJong RJ, Brant SV.Scratching the Itch: Updated Perspectives on the Schistosomes Responsible for Swimmer’s Itch around the World.Pathogens. 2022 May 16;11(5):587. doi: 10.3390/pathogens11050587.Blankespoor CL, Blankespoor HD, DeJong RJ.Swimmer’s itch control: Timely waterfowl brood relocation significantly reduces an avian schistosome population and human cases on recreational lakes.PLoS One. 2024 Feb 15;19(2):e0288948. doi: 10.1371/journal.pone.0288948.Sridhar SC, Deo SC.Marine and other aquatic dermatoses.Indian Journal of Dermatology. 2017;62(1):66-78. doi:10.4103/0019-5154.198052National Capital Poison Center.Seabather’s Eruption Symptoms and Treatment.Chang T, Hunt BPV, Hirai J, Suttle CA.Divergent RNA viruses infecting sea lice, major ectoparasites of fish.PLoS Pathog. 2023 Jun 22;19(6):e1011386. doi:10.1371/journal.ppat.1011386.Thornton NJ, Garcia B, Hoyer P.Aquatic Antagonists: Marine Rashes (Seabather’s Eruption and Diver’s Dermatitis).Cutis. 2022 May;109(5):255-260. doi: 10.12788/cutis.0522.Khodaee M, Edelman GT, Spittler J, et al.Medical care for swimmers.Sports Med Open.2015;2:27. doi:10.1186/s40798-016-0051-2Jacob JS, Tschen J.Hot Tub-Associated Pseudomonas Folliculitis: A Case Report and Review of Host Risk Factors.Cureus. 2020 Sep 23;12(9):e10623. doi: 10.7759/cureus.10623.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Schols R, Smitz N, Vanderheyden A, Huyse T.Expanding the swimmer’s itch pool of the Benelux: a first record of the neurotropic Trichobilharzia regenti and potential link to human infection.Parasit Vectors. 2024 Mar 13;17(1):126. doi:10.1186/s13071-024-06218-4.Tracz ES, Al-jubury A, Buchmann K, Bygum A.Outbreak of swimmer’s itch in Denmark.Acta Derm Venereol. 2019;99(12):1116-20. doi:10.2340/00015555-3309Loker ES, DeJong RJ, Brant SV.Scratching the Itch: Updated Perspectives on the Schistosomes Responsible for Swimmer’s Itch around the World.Pathogens. 2022 May 16;11(5):587. doi: 10.3390/pathogens11050587.Blankespoor CL, Blankespoor HD, DeJong RJ.Swimmer’s itch control: Timely waterfowl brood relocation significantly reduces an avian schistosome population and human cases on recreational lakes.PLoS One. 2024 Feb 15;19(2):e0288948. doi: 10.1371/journal.pone.0288948.Sridhar SC, Deo SC.Marine and other aquatic dermatoses.Indian Journal of Dermatology. 2017;62(1):66-78. doi:10.4103/0019-5154.198052National Capital Poison Center.Seabather’s Eruption Symptoms and Treatment.Chang T, Hunt BPV, Hirai J, Suttle CA.Divergent RNA viruses infecting sea lice, major ectoparasites of fish.PLoS Pathog. 2023 Jun 22;19(6):e1011386. doi:10.1371/journal.ppat.1011386.Thornton NJ, Garcia B, Hoyer P.Aquatic Antagonists: Marine Rashes (Seabather’s Eruption and Diver’s Dermatitis).Cutis. 2022 May;109(5):255-260. doi: 10.12788/cutis.0522.Khodaee M, Edelman GT, Spittler J, et al.Medical care for swimmers.Sports Med Open.2015;2:27. doi:10.1186/s40798-016-0051-2Jacob JS, Tschen J.Hot Tub-Associated Pseudomonas Folliculitis: A Case Report and Review of Host Risk Factors.Cureus. 2020 Sep 23;12(9):e10623. doi: 10.7759/cureus.10623.
Schols R, Smitz N, Vanderheyden A, Huyse T.Expanding the swimmer’s itch pool of the Benelux: a first record of the neurotropic Trichobilharzia regenti and potential link to human infection.Parasit Vectors. 2024 Mar 13;17(1):126. doi:10.1186/s13071-024-06218-4.
Tracz ES, Al-jubury A, Buchmann K, Bygum A.Outbreak of swimmer’s itch in Denmark.Acta Derm Venereol. 2019;99(12):1116-20. doi:10.2340/00015555-3309
Loker ES, DeJong RJ, Brant SV.Scratching the Itch: Updated Perspectives on the Schistosomes Responsible for Swimmer’s Itch around the World.Pathogens. 2022 May 16;11(5):587. doi: 10.3390/pathogens11050587.
Blankespoor CL, Blankespoor HD, DeJong RJ.Swimmer’s itch control: Timely waterfowl brood relocation significantly reduces an avian schistosome population and human cases on recreational lakes.PLoS One. 2024 Feb 15;19(2):e0288948. doi: 10.1371/journal.pone.0288948.
Sridhar SC, Deo SC.Marine and other aquatic dermatoses.Indian Journal of Dermatology. 2017;62(1):66-78. doi:10.4103/0019-5154.198052
National Capital Poison Center.Seabather’s Eruption Symptoms and Treatment.
Chang T, Hunt BPV, Hirai J, Suttle CA.Divergent RNA viruses infecting sea lice, major ectoparasites of fish.PLoS Pathog. 2023 Jun 22;19(6):e1011386. doi:10.1371/journal.ppat.1011386.
Thornton NJ, Garcia B, Hoyer P.Aquatic Antagonists: Marine Rashes (Seabather’s Eruption and Diver’s Dermatitis).Cutis. 2022 May;109(5):255-260. doi: 10.12788/cutis.0522.
Khodaee M, Edelman GT, Spittler J, et al.Medical care for swimmers.Sports Med Open.2015;2:27. doi:10.1186/s40798-016-0051-2
Jacob JS, Tschen J.Hot Tub-Associated Pseudomonas Folliculitis: A Case Report and Review of Host Risk Factors.Cureus. 2020 Sep 23;12(9):e10623. doi: 10.7759/cureus.10623.
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