Cruise ships are relatively small, crowded spaces where infection control is especially important. There is limited information available about the composition of the microbiome found on frequently-touched surfaces in cruise ships. This study describes the microbial composition of cruise ship surfaces and crew member skin microbiomes. Fingertips of crew members and surfaces were sampled using agar plates. After culturing, DNA was extracted and sequenced using Nanopore long-read whole metagenome sequencing. Classification was performed using Kraken2, and antibiotic resistance genes were identified using the CARD RGI Resistance Gene Identifier. In total, 10’369’710 reads were generated. In the 15 hand samples, 2’495 species were detected. 99.9% of the samples were identified as bacterial, which indicates a limitation of the extraction methods. The majority of the hand samples belonged to the Staphylococcus genus (69.38%). Significant individual differences were observed in the microbiome composition of each sample. For the surface samples, 22 species that were present in all or almost all surfaces were listed. Among them, many potentially dangerous pathogenic bacteria were identified, such as Acinetobacter baumannii , Enterobacter species, Escherichia coli , Klebsiella pneumoniae , and Staphylococcus aureus. Their antimicrobial resistance genes were also detected in the analyzed sample. Surface samples had a similar composition to hand samples, indicating a strong correlation. In both cases, known pathogens were frequently isolated, suggesting that these bacteria are present throughout our environment. This highlights the importance of regular cleaning and disinfection in crowded areas, such as cruise ships. Key findings Diverse Microbiomes 2,495 bacterial species were found in the hand samples, with large individual differences. The most common bacteria on hands were from the Staphylococcus genus, making up 69% of the sample. Bacterial overlap between hands and surfaces The bacteria on surfaces closely resembled those found on hands, suggesting frequent transfer between humans and the environment. 22 bacterial species were present on almost all surfaces, including potential pathogens like Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and Acinetobacter baumannii. Antibiotic Resistance Genes Bacteria on the ship contained genes that can make them resistant to antibiotics, raising concerns about their spread in crowded settings. These resistance genes were found even on regularly cleaned surfaces, indicating that cleaning alone may not fully eliminate resistant bacteria. Implications This study highlights how bacteria move between people and the environment, emphasizing the need for improved hand hygiene and thorough disinfection. While the ship’s cleaning protocols were in place, potentially harmful bacteria and antibiotic-resistant genes were still detected, showing the challenge of maintaining a microbially safe environment.
Bánsághi et al. (Fri,) studied this question.