Legionella confirmation in cooling tower water: Comparison of culture, real-time PCR and next generation sequencing

Authors

• Maha Farhat, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Raja A. Shaheed, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Haidar H. Al-Ali, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Abdullah S. Al-Ghamdi, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Ghadeer M. Al-Hamaqi, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Hawraa S. Maan, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Zainab A. Al-Mahfoodh, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
• Hussain Z. Al-Seba, From the Department of Biochemistry (Farhat), Department of Epidemic Diseases Research (Farhat), College of Medicine (Shaheed, Aall-Ali, Al-Ghamdi, Al-Hamaqi, Maan, Al-Mahfoodh, Al-Seba), Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia

Abstract

Objectives: To investigate the presence of Legionella spp in cooling tower water. Legionella proliferation in cooling tower water has serious public health implications as it can be transmitted to humans via aerosols and cause Legionnaires’ disease. Methods: Samples of cooling tower water were collected from King Fahd Hospital of the University (KFHU) (Imam Abdulrahman Bin Faisal University, 2015/2016). The water samples were analyzed by a standard Legionella culture method, real-time polymerase chain reaction (RT-PCR), and 16S rRNA next-generation sequencing. In addition, the bacterial community composition was evaluated. Results: All samples were negative by conventional Legionella culture. In contrast, all water samples yielded positive results by real-time PCR (10 5 to 10 6 GU/L). The results of 16S rRNA next generation sequencing showed high similarity and reproducibility among the water samples. The majority of sequences were Alpha-, Beta-, and Gamma-proteobacteria, and Legionella was the predominant genus. The hydrogen-oxidizing gram-negative bacterium Hydrogenophaga was present at high abundance, indicating high metabolic activity. Sphingopyxis, which is known for its resistance to antimicrobials and as a pioneer in biofilm formation, was also detected. Conclusion: Our findings indicate that monitoring of Legionella in cooling tower water would be enhanced by use of both conventional culturing and molecular methods.

Article Type

Research Article

First Page

137

Last Page

141

Recommended Citation

Farhat, Maha; Shaheed, Raja A.; Al-Ali, Haidar H.; Al-Ghamdi, Abdullah S.; Al-Hamaqi, Ghadeer M.; Maan, Hawraa S.; Al-Mahfoodh, Zainab A.; and Al-Seba, Hussain Z. (2018) "Legionella confirmation in cooling tower water: Comparison of culture, real-time PCR and next generation sequencing," Saudi Medical Journal: Vol. 39: Iss. 2, Article 5.
DOI: https://doi.org/10.15537/smj.2018.2.21587