High Rate of Simkania negevensis among Canadian Inuit Infants Hospitalized with Lower Respiratory Tract Infections

Pediatric Infectious Disease Unit, Soroka University Medical Center, Ben-Gurion University, Beer-Sheva, Israel.
Infectious Diseases (Impact Factor: 1.5). 02/2003; 35(8):506-8. DOI: 10.1080/00365540310014648
Source: PubMed


To determine the prevalence of Simkania negevensis in causing pulmonary infections in children, nasopharyngeal washes were obtained from 22 infants hospitalized with acute bronchiolitis in the Baffin Island, Canada. 14 (63.6%) were positive for S. negevensis. Mixed infections with other respiratory viruses were common. All patients recovered without specific antibiotic treatment. Even though a high prevalence of S. negevensis was found, this organism may potentially well be an opportunistic agent rather than a true pathogen.

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    • "Seroepidemiological studies from different parts of the world demonstrated remarkable differences in seropositivity rates that range from as low as 4.3% to approximately 80% (Friedman et al., 1999, 2003, 2006; Johnsen et al., 2005; Yamaguchi et al., 2005; Korppi et al., 2006; Donati et al., 2013). In addition, infection with Simkania has been associated with respiratory diseases, such as pneumonia , exacerbation of chronic obstructive pulmonary disease and bronchiolitis (Lieberman et al., 1997, 2002; Kahane et al., 1998; Greenberg et al., 2003; Friedman et al., 2003, 2006; Kumar et al., 2005; Fasoli et al., 2008; Heiskanen-Kosma et al., 2008; Nascimento-Carvalho et al., 2009). However, Niemi and coworkers (2001) were not able to detect an association of Simkania with respiratory diseases. "
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    • "They are obligate intracellular gram-negative bacteria which replicate within endocytic vacuoles of eukaryotic cells i.e. amoebae, human epithelial cells and macrophages [3]. Simkania has been reported as an emerging pathogen associated with several types of respiratory tract infection such as bronchiolitis in infants [4], [5], [6], [7], community acquired pneumonia [8], [9], [10], chronic obstructive pulmonary disease in adults [11] and acute rejection in lung transplant recipients [12]. Moreover, seroprevalence rates in adults between 46–80% suggest a broad distribution of the organism in human populations [13]. "
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