Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Wearing glasses – a health risk?

30.11.2018

Can I infect myself with my own glasses? And how should I clean them to keep the risk of infection to a minimum? Glasses are in regular contact with hands and skin – but until now almost nothing was known about the microbial colonization of these everyday objects. Now, for the first time, a study examines in detail the microflora of glasses. Heading up the study is the microbiologist Prof. Dr. Markus Egert of Furtwangen University, well-known for his research into the bacterial contamination of kitchen sponges and other everyday objects. His book “Ein Keim kommt selten allein” (Germs love company), published by Ullstein, came out in August.

In 2018 approximately 44.2 million Germans over the age of 14 wore glasses on a regular or occasional basis. Research has been done on the bacterial contamination of glasses for surgeons, or on 3D-glasses lent out in cinemas, but until now there were no academic findings on normal eyeglasses worn by the general population.


Germs especially at the frame of glasses

Theresa Mühlbauer

For the study, swabs were taken from seven different areas (frame, nose pads, lenses) on each of 31 pairs of glasses, and after cultivating the bacteria found on a culture media, they were examined in detail. Twenty-one pairs of glasses belonged to students and staff of Furtwangen University, whereas 10 pairs belonged to residents of a senior citizen home.

“Bacteria were found on all the glasses we examined,” explained Prof. Dr. Markus Egert. “This was most evident in the areas with direct skin contact, such as the temples, the arms which extend over the ears, and the nose pads. The lenses themselves had the lowest levels of contamination.” The highest level recorded was 660,000 bacteria/cm2 on a nose pad.

On average, across all the areas swabbed, the university-glasses were no more densely populated with bacteria than the home-glasses: 1,400 as opposed to 2,080 bacteria/cm2. However, substantially more bacteria were found on the glasses worn by the residents of the senior citizen home than on those worn by the university students and staff (230 bacteria/cm2 as opposed to 40 bacteria/cm²).

One possible explanation for this could be that the age-related weaker eyesight of the home residents actually promotes the contamination of the glasses. Because the owners cannot see the fingerprints and other smudges on the lenses as well, they clean them less often. On the glasses from the home, there was also a greater variety of types of bacteria (ten types as opposed to two types on the university-glasses). This makes sense — the skin flora also becomes more varied with increasing age.

What was mainly identified were typical skin and mucous membrane bacteria, above all, of the Staphylococcus type. The percentage of potential pathogens, bacteria which are potentially harmful to the health, was approximately 60%. These bacteria can cause infections in people with weaker immune systems.

Causes of eye infections such as conjunctivitis and endophthalmitis were also found: Staphylococcus epidermidis; Staphylococcus hominis and Staphylococcus aureus. Some of these also have variants which are resistant to antibiotics.

In standardized cleaning tests it was shown that through rubbing not only the lenses, but also the whole glasses with a pre-moistened lens cleaning wipe, germs could be reduced by 94 - 99%. Lens cleaning wipes with an alcohol-free solution less damaging to the plastic of the frame, were also tested. Dry cleaning was less effective in the removal of germs, achieving only an 85 - 90% reduction.

“The study clearly shows that glasses act as a germ carrier,” summed up Prof. Dr. Markus Egert. Further studies will show whether connections can be made between the flora of the glasses and repetitive eye infections, so whether glasses can act as a type of germ reservoir.

In addition they will be investigating whether glasses can also provide a hiding place for antibiotic-resistant germs such as MRSA (multi-resistant Staphylococcus aureus), particularly in a hospital environment.

“Glasses definitely don’t present any risk of infection for healthy people,” assured Prof. Dr. Markus Egert. “In cases of repetitive eye infection or treatment for an MRSA infection, disinfection of the glasses should also be considered.”

Publishing
Title of paper: A view to a kill? - Ambient bacterial load of frames and lenses of spectacles and evaluation of different cleaning methods
Journal: PLOS One, https://doi.org/10.1371/journal.pone.0207238 (open access)

Research project: joint project between Furtwangen University and Carl Zeiss Vision International GmbH (Aalen), the University Eye Hospital Tübingen and the Singen Medical Laboratory, within the framework of the CoHMed (Connected Health in Medical Mountains) project funded by the Federal Ministry of Education and Research which fosters cooperation between Furtwangen University and the regional medical technology industry.

Wissenschaftliche Ansprechpartner:

Prof. Dr. Markus Egert, ege@hs-furtwangen.de

Originalpublikation:

Journal: PLOS One, https://doi.org/10.1371/journal.pone.0207238

Jutta Neumann | idw - Informationsdienst Wissenschaft
Further information:
http://www.hs-furtwangen.de

Further reports about: MRSA Staphylococcus Staphylococcus aureus bacteria contamination germs lenses

More articles from Life Sciences:

nachricht An ion channel with a doorkeeper: The pH of calcium ions controls ion channel opening
25.06.2019 | Johannes Gutenberg-Universität Mainz

nachricht Symbiotic upcycling: Turning “low value” compounds into biomass
25.06.2019 | Max-Planck-Institut für Marine Mikrobiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fraunhofer IDMT demonstrates its method for acoustic quality inspection at »Sensor+Test 2019« in Nürnberg

From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.

Reducing machine downtime, manufacturing defects, and excessive scrap

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

For a better climate in the cities: Start-up develops maintenance-free, evergreen moss façades

25.06.2019 | Architecture and Construction

An ion channel with a doorkeeper: The pH of calcium ions controls ion channel opening

25.06.2019 | Life Sciences

Cooling with the sun

25.06.2019 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>