Almost every household comes with its own washing machine and it has one basic function—to help clean dirty clothes. However, people often overlook that this does not mean that washing machines are clean all the time. A new study suggests that washing machines can be one of the dirtiest appliances in the house that it could harbor drug-resistant bacteria that could put people's health at risk.
The team of researchers described an isolated case in a German hospital where the spread of drug-resistant bacteria among newborns were linked to the washing machine used. It has been the first time that a washing machine was reported to have been the source of the spread of harmful pathogens among infant patients in the hospital.
Although the case was considered, then, as "highly unusual" for a hospital because they were using a household type of washing machine instead of the industrial type that is required of them as a healthcare facility, Dr. Ricarda Schmithausen, senior physician at the Institute for Hygiene and Public Health at the University Hospital Bonn in Germany and lead author of the study, said that it is important that this unique situation is given proper attention.
"It may be unique in the hospital as an industrial setting, but it definitely affects the household washers," Dr. Schmithausen said. Washing machines these days are more energy efficient, which means they use lower water temperatures. Sadly, such type of efficiency is less likely to kill pathogens. Although the risk is there, experts say that an average person does not need to worry about their washing machines and how it could harbor deadly bacteria.
"Washing machines have been designed to help clean the dirty clothes, but they are not designed to make each one sterile," said Dr. Amesh Adalja, a specialist in infectious diseases. She is also a scholar at The Johns Hopkins Center for Health and Security in Baltimore. Though she was not directly involved in the study, she said, "The water used in most washing machines are not hot enough to kill every form of bacteria in one's clothing, but this is not something people should worry about."
She also emphasized that this type of bacteria does not matter, because there are a lot of other bacteria present in the clothing and in the human body that are not harmful. "A vast majority of bacteria present in the environment do not cause health concerns for people," Adalja said.
The results of the study were published in the Applied and Environmental Microbiology journal: the doctors from the German facility were left wondering why the newborns in their facility always tested positive for Klebsiella Oxytoca, a drug-resistant bacteria. The bacterium is known to cause serious infections, but it was found on the newborns' skin without causing any form of infection. However, its presence still left doctors concerned, given that it could be the source for pneumonia and urinary tract infections, particularly in patients who already have a low immune system.
In a statement, Dr. Martin Exner, the director of the hospital directed that "the laundry be done at higher temperatures or use a more effective disinfectant to avoid the spread of pathogens that could put patients at higher risk." However, the report of Adalja and the team describes this as a "special circumstance" that is common even in the hospital setting. Outside the hospital, it is best to practice proper hygiene practices like handwashing.
