Health Less cleanliness could help to repress diseases

Less cleanliness - Current hygiene measures could be partly counterproductive

Health experts repeatedly point out that hygiene is often far too short, and this can contribute to the spread of infectious diseases. But according to researchers, the current hygiene measures to combat aggressive germs could be partially counterproductive. Less cleanliness could help to repress diseases.

Too much hygiene can be harmful

Again and again it is pointed out to pay attention to proper kitchen hygiene, in order to avoid infections with health-endangering pathogens. The reference to consistent hand hygiene is constantly repeated. However, while it is important to keep yourself and your environment clean, experts repeatedly point out hysterical hygiene as too much hygiene favors the development of allergies. An interdisciplinary research team also reports that less cleanliness could bring any health benefits.

Cleaning with disinfectants disturbs the natural species composition of the existing microorganisms. This could even promote the spread of pathogens. (Image: M. Schuppich / fotolia.com)

Turn existing strategies upside down

If the same laws of biodiversity apply on our bodies and in our homes as they are out in nature, our current hygiene measures to combat aggressive germs would be partially counterproductive.

An interdisciplinary team of researchers from the German Center for Integrative Biodiversity Research (iDiv) reports in the journal Nature Ecology & Evolution and suggests that the role of biodiversity in microorganisms in the ecosystems body and house should be examined more intensively.

According to a statement, the findings could turn existing strategies for fighting infectious diseases and resistant germs on their heads.

Resistant to pathogens

According to the experts, ecosystems such as meadows and forests with high biodiversity are more resistant to disturbances such as invading alien species, climatic fluctuations or pathogens.

By reducing this diversity, basic functions of communities in the ecosystem are lost. This so-called stability theory has been proven in hundreds of biological studies.

However, these mainly dealt with the world of animals and plants. Looking at our body or home through a microscope, an equally diverse community of microorganisms opens up.

Possibly similar laws apply to them as to the "big" ecosystems. This would have far-reaching consequences for our health care.

Microbiodiversity is controlled by antibiotics and disinfectants

Researchers at the iDiv research center now propose testing the theories of ecosystem research on our immediate environment and its microorganisms.

"We are influencing this micro-biodiversity on a daily basis, especially by combating it, for example, with disinfectants or antibiotics - actually with the aim of promoting good health," said Robert Dunn, a professor at the University of North Carolina State and the University of Copenhagen.

The ecologist wrote the article during a one-year stay at iDiv together with iDiv scientist Nico Eisenhauer, professor at the University of Leipzig.

"These interventions in microbial species compositions could hinder the natural containment of pathogens," the researchers say.

Microorganisms form their own ecosystems

According to the ecological niche model, plants or animals divide up the available resources in their habitat, with species with similar needs competing with each other.

New species are finding it hard to establish themselves, at least in a stable ecosystem. However, species that are species-poor or disturbed by humans are much more likely to spread alien species.

Microorganisms also form their own ecosystems. There are currently more than two hundred thousand species known to live in human dwellings as well as on and in human bodies.

Half of them make up bacteria in human dwellings, thousands of bacteria live on our bodies. In addition, there are around forty thousand types of fungi in our homes, but they are less likely to find human bodies.

Propagation of dangerous germs is favored

"Pathogens in our environment are comparable to invasive organisms in nature," explained the ecologist Eisenhauer.

"If you transfer the insights from the large habitats to the world of microbes, you have to fear that our notorious use of disinfectants and antibiotics even increases the spread of dangerous germs, because it disturbs the natural species community."

This has been proven, for example, for rod-shaped bacteria of the species Clostridium difficile, which cause intestinal inflammation with diarrhea.

After taking antibiotics they were able to spread faster. So-called non-tuberculous mycobacteria (NTMs), which form a biofilm primarily on showerheads and can sometimes trigger diseases, are mainly found in chlorinated water.

They are largely free to proliferate on metal shower hoses, while plastic shower hoses, which favor a rich community of microorganisms, have lower levels of NTMs.

Diseases preventive bacterial communities

Bacteria communities that prevent disease can also be actively produced.

For example, scientists discovered in the 1960s that babies whose noses and navels were inoculated with harmless strains of the bacterium Staphylococcus aureus were rarely colonized by S. aureus 80/81.

This bacterium can cause diseases ranging from skin infections to life-threatening blood poisoning or pneumonia.

Another example is stool transplantation: By transferring a healthy community of microorganisms from person to person, it is possible to treat intestinal infections.

Only a small proportion of microorganisms triggers diseases

Is our fear of bacteria and Co. so unfounded and their knee-jerk fight even dangerous?

"We are not doctors," Eisenhauer said. "I would certainly not recommend a surgeon to work non-sterile on the open body," said the ecologist.

"However, as far as surfaces are concerned, targeted inoculations with a select microbial community could potentially prevent the spread of dangerous pathogens."

In any case, as stated in the communication, only a relatively small proportion of the microorganisms in our environment actually cause disease.

This also applies to insects and other arthropods, which are usually regarded in homes and houses as troublemakers - especially spiders.

As robbers, these provide important ecosystem services by decimating mosquitoes, bed bugs, cockroaches or house flies, which in turn can transmit diseases. "We just have to let her," Robert Dunn said.

Where the theories of biodiversity and ecosystem research in the health sector apply, the three authors should be systematically investigated.

On the one hand, Eisenhauer suggests to test in which microbial society common pathogens can spread better or worse on surfaces. In the longer term, the ideal species composition of "good" versus "bad" microbes should be found. (Ad)