About Careers Internship MedBlog Contact us

Study Says Contact Lens Cases are Home to Pathogenic Amoebae

by Rajashri on October 21, 2008 at 2:48 PM
Font : A-A+

 Study Says Contact Lens Cases are Home to Pathogenic Amoebae

Contact lens cases are often contaminated with Acanthamoeba which cannot be killed by normal contact lens solution, according to a new Spanish study.

Published in the Journal of Medical Microbiology, the study report describes Acanthamoeba as one of the most common types of protozoa in soil, which is often found in fresh water.


The researchers behind the study say that most species eat bacteria, and some can cause infections in humans.

They have revealed that one of the diseases caused by Acanthamoeba is called amoebic keratitis, an infection of the eye which is very painful and can cause blindness.

According to them, about 85 per cent of all amoebic keratitis cases occur in people who wear contact lenses.

The team say that people who wear lenses while swimming or use tap water to rinse their lenses have an increased risk of infection, as amoeba is usually present in chlorinated swimming pools and domestic tap water.

"The prevalence of this infection has risen in the past twenty years worldwide, mainly because more people are wearing contact lenses," said Dr Basilio Valladares from the University Institute of Tropical Diseases and Public Health of the Canary Islands, University of La Laguna.

"When people rinse their contact lens cases in tap water, they become contaminated with amoebae that feed on bacteria. They are then transferred onto the lenses and can live between the contact lens and the eye. This is particularly worrying because commercial contact lens solutions do not kill the amoebae," the researcher added.

For their study, the researchers examined 153 contact lens cases, 90 containing lenses, from people in Tenerife who were showing no symptoms of infection.

They observed that 65.9 per cent of the cases and lenses were contaminated with pathogenic Acanthamoeba, and 30 per cent of the amoebae identified were highly pathogenic.

While no pathogenic strains were found in daily contact lenses, several pathogenic amoebae were isolated from monthly and bi-monthly lenses.

The two-year use lenses that were analysed contained a high percentage of pathogenic amoebae due to a lack of hygiene and poor care of the lenses.

"We tested the effect of two standard drugs on the amoebae. We found that the antibiotic ciprofloxacin and the antiseptic chlorhexidine both kill Acanthamoeba. However, the concentrations of chlorhexidine found in contact lens maintenance solutions are not high enough to kill pathogenic strains, so most lens solutions do not protect against amoebic keratitis," said Dr. Valladares.

"At the moment, we are developing a contact lens maintenance solution that can kill pathogenic Acanthamoeba species.

"Studies have shown that these amoebae are more common among contact lens users in Tenerife than in Scotland, perhaps because of the warmer climate. Contact lens users are at greater risk of infection here and we hope we will be able to prevent and treat the diseases caused by these amoebae more effectively in the near future," the researcher added.

Source: ANI


Recommended Readings

Latest General Health News

What Are the Consequences of Celebrities Endorsing Tobacco?
In India, youth must be aware of the diseases linked to cigarette smoking and tobacco consumption, causing a form of healthcare emergency.
 People Living Close to the Seaside Enjoy Better Health
Direct coastal access may represent a viable route to public health promotion, but the relationships of coastal living are not strongest among lower-income groups.
 Over Four Million Gardeners Place Their Hearing in Danger
New research by Tinnitus UK has found that over four million gardeners are putting their hearing capacity at risk this summer without using safety protection.
Breaking the Barrier: Unraveling Mucus Plugs to Save Lives in COPD
Mucus plugs could be targeted to help reduce fatalities from chronic obstructive pulmonary disease.
 Disease Modifying Therapies for Multiple Sclerosis Continue to Drive Up Healthcare Cost
The development of reliable curative therapies for multiple sclerosis could significantly reduce the economic burden of the disease on patients and wider society.
View All
This site uses cookies to deliver our services.By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use  Ok, Got it. Close

Study Says Contact Lens Cases are Home to Pathogenic Amoebae Personalised Printable Document (PDF)

Please complete this form and we'll send you a personalised information that is requested

You may use this for your own reference or forward it to your friends.

Please use the information prudently. If you are not a medical doctor please remember to consult your healthcare provider as this information is not a substitute for professional advice.

Name *

Email Address *

Country *

Areas of Interests