Indian Journal of Medical Microbiology Home 

CORRESPONDENCE
[Download PDF]
Year : 2016  |  Volume : 34  |  Issue : 1  |  Page : 110--111

Investigation on the effect of the ecological parameters on the prevalence of Laribacter hongkongensis in freshwater fish and in human

Q Kong, J Sun, L Shen, J Cha, H Xu, H Jin, H Yu, X Ni 
 Department of Disinfection and Vector Control, Hangzhou Center for Disease Control and Prevention, Hangzhou City, Zhejiang Province, P. R. China

Correspondence Address:
X Ni
Department of Disinfection and Vector Control, Hangzhou Center for Disease Control and Prevention, Hangzhou City, Zhejiang Province
P. R. China

How to cite this article:
Kong Q, Sun J, Shen L, Cha J, Xu H, Jin H, Yu H, Ni X. Investigation on the effect of the ecological parameters on the prevalence of Laribacter hongkongensis in freshwater fish and in human.Indian J Med Microbiol 2016;34:110-111

How to cite this URL:
Kong Q, Sun J, Shen L, Cha J, Xu H, Jin H, Yu H, Ni X. Investigation on the effect of the ecological parameters on the prevalence of Laribacter hongkongensis in freshwater fish and in human. Indian J Med Microbiol [serial online] 2016 [cited 2020 Oct 30 ];34:110-111
Available from: https://www.ijmm.org/text.asp?2016/34/1/110/167670

Full Text

Dear Editor,

Laribacter hongkongensis was a newly discovered bacterium associated with community-acquired diarrhoea.[1] Carp varieties of fishes and edible frogs of fresh water ecosystem were natural sources of infection to human.[2] As prevalence of bacteria in aquatic environment was always affected by conditions of water,[3] we made an investigation on correlation among ecological parameters of water, prevalence of L. hongkongensis in freshwater fish and in human. L. hongkongensis was isolated monthly from faecal samples of grass carp and outpatients with community-acquired diarrhoea in a hospital in China from November 2011 to October 2012. Water temperature, air temperature and pH value of the ponds were detected when fish were sampled from them. Pearson correlation test was used for correlation analysis.

Total positive rate of isolation of L. hongkongensis was 7.82 (56/716) in fish, and 0.36 (10/2815) in patients [Table 1]. Vibrio cholerae, Shigella, Salmonella, Escherichia O157 and Vibrio parahaemolyticus were not isolated from 10 positive faecal specimens of patients. Prevalence of L. hongkongensis in patients were highly correlated with prevalence in fish (r = 0.763, P = 0.004), but positive rate in patients was much lower than in fish. It might be due to low risk of infection and low pathogenicity of the bacteria. However, more evidences were still needed to support the hypothesis, as the pathogenesis of L. hongkongensis was not clear, and the bacteria as pathogen for gastroenteritis remained to be questioned.[4]{Table 1}

Water temperatures (r = 0.659, P = 0.020) and air temperatures (r = 0.715, P = 0.009) were correlated with the positive rate of L. hongkongensis in fish. The pH value of water had no correlation (r = −0.402, P = 0.195). These findings were similar with the investigation of Lau, which was launched at low latitude area where the lowest air temperature was 17.5°C in the survey.[5] Our study firstly proved that findings of Lau were also fit for conditions at middle-high latitude regions where temperature might lower than 0°C in winter. We also found that when water temperature was lower than 10°C, the positive rate of L. hongkongensis in fish would decrease to zero [Table 1].

Our study found that prevalence of L. hongkongensis in patients with diarrhoea was highly correlated with prevalence in fish. Prevalence of L. hongkongensis in fish had obvious seasonal characteristics at middle-high latitude regions and could be affected by air temperature and water temperature. These findings would contribute to pathogenesis study of L. hongkongensis and prevention of related disease.

References

1Woo PC, Kuhnert P, Burnens AP, Teng JL, Lau SK, Que TL, et al. Laribacter hongkongensis: A potential cause of infectious diarrhea. Diagn Microbiol Infect Dis 2003;47:551-6.
2Raja MK, Lulu SS, Ghosh AR. A novel pathogen for gastroenteritis: Laribacter hongkongensis. Indian J Med Microbiol 2013;31:204.
3León Robles A, Acedo Félix E, Gomez-Gil B, Quiñones Ramírez EI, Nevárez-Martínez M, Noriega-Orozco L. Relationship of aquatic environmental factors with the abundance of Vibrio cholerae, Vibrio parahaemolyticus, Vibrio mimicus and Vibrio vulnificus in the coastal area of Guaymas, Sonora, Mexico. J Water Health 2013;11:700-12.
4Farmer JJ 3rd, Gangarosa RE, Gangarosa EJ. Does Laribacter hongkongensis cause diarrhoea, or does diarrhoea “cause” L. hongkongensis? Lancet 2004;363:1923-4.
5Lau SK, Woo PC, Fan RY, Lee RC, Teng JL, Yuen KY. Seasonal and tissue distribution of Laribacter hongkongensis, a novel bacterium associated with gastroenteritis, in retail freshwater fish in Hong Kong. Int J Food Microbiol 2007;113:62-6.