Doctors clarify the risks of developing infections in COVID hospitals

It is widely known that the main problem of hospitals is nosocomial infections, the occurrence of which ranges from 15% to 50% in all countries and continents. RUDN University doctors worked in hospital 'Red zones', supervised the management of patients with a new coronavirus infection, and identified the most common opportunistic bacteria that can most often cause secondary bacterial complications in patients with COVID-19 in the ICU. Practical application of the results of the conducted studies will help to reduce the risks of bacterial complications in hospitals. The results are published in the International Journal of Environmental Research and Public Health.

In most cases, patients with COVID-19 in the ICU develop infections that can cause complications and increase lethality. The most common pathogens of co-infections with COVID-19 are bacteria, therefore, doctors often prescribe antibacterial drugs as a preventive measure when treating coronavirus. However, because of uncontrolled antibiotics use of bacteria become resistant to them and practically invincible. In this case, the patients' own bacterial flora and nosocomial bacteria can become extremely dangerous. RUDN University doctors assessed the risks of nosocomial infections and identified the main types of potentially dangerous bacteria.

"Medical staff and patients are in close contact with different solid surfaces that are of particular interest as research objects due to the ability of microorganisms to be preserved on such surfaces for at least several days. In this regard, it is important to monitor the microbiological composition in a hospital setting to obtain up-to-date information about the epidemiological state and the necessity to take appropriate measures to prevent the spread of various infections, including nosocomial ones", said Olga Burgasova, professor of the Department of Infectious Diseases with the Course of Epidemiology and Phthisiology at RUDN University.

The researchers took samples from various surfaces in hospital wards, isolation wards, corridors, restrooms, and staff offices. Special attention was paid to objects and surfaces that patients and doctors touch most often: door and window handles, switches, bedside tables. In addition, to check whether bacteria were brought into the wards by patients, doctors took samples from the nasopharynx of patients. Then scientists identified the types of microorganisms in samples using a PCR test and sequencing.

The most common microorganisms were Coagulase negative staphylococci (CoNS) and Klebsiella pneumoniae. They were found in 100% and 64% of samples. These bacteria are conditionally pathogenic. Normally they do not harm a person, but with a decrease in immunity, they become aggressive. In addition, on the door handles and on the floor, scientists found pathogenic bacteria Staphylococcus aureus and Pseudomonas aeruginosa. They pose the greatest danger to ICU patients, who are unable to resist bacterial infections. Interestingly, there were no listed pathogens in the nasopharyngeal swabs of patients with COVID-19, so it is unlikely that the patients brought these bacteria to the hospital themselves. Probably, it can be explained by ineffective disinfection of premises after previously hospitalized patients, as well as the need to monitor the medical personnel themselves.

"In our study, all the surfaces were contaminated with at least one pathogen, regardless of the department. The places with the greatest number of potentially dangerous bacteria were door handles and the floors. We have demonstrated the importance of timely disinfection and constant monitoring of microbial contamination. This will help to avoid infections and complications in patients", said Olga Burgasova, professor of the Department of Infectious Diseases with the Course of Epidemiology and Phthisiology at RUDN University.

More information:
Andrei A. Pochtovyi et al, Contamination of Hospital Surfaces with Bacterial Pathogens under the Current COVID-19 Outbreak, Int. J. Environ. Res. Public Health (2021), DOI:10.3390/ijerph18179042

Provided by RUDN University