Factors associated with occurrence of <i>Bartonella</i> infection in blood donors in Campinas, Brazil.

<p>Factors associated with occurrence of <i>Bartonella</i> infection in blood donors in Campinas, Brazil.</p

Risk Factors for <i>Bartonella</i> species Infection in Blood Donors from Southeast Brazil

<div><p>Bacteria from the genus <i>Bartonella</i> are emerging blood-borne bacteria, capable of causing long-lasting infection in marine and terrestrial mammals, including humans. <i>Bartonella</i> are generally well adapted to their main host, causing persistent infection without clinical manifestation. However, these organisms may cause severe disease in natural or accidental hosts. In humans, <i>Bartonella</i> species have been detected from sick patients presented with diverse disease manifestations, including cat scratch disease, trench fever, bacillary angiomatosis, endocarditis, polyarthritis, or granulomatous inflammatory disease. However, with the advances in diagnostic methods, subclinical bloodstream infection in humans has been reported, with the potential for transmission through blood transfusion been recently investigated by our group. The objective of this study was to determine the risk factors associated with <i>Bartonella</i> species infection in asymptomatic blood donors presented at a major blood bank in Southeastern Brazil. Five hundred blood donors were randomly enrolled and tested for <i>Bartonella</i> species infection by specialized blood cultured coupled with high-sensitive PCR assays. Epidemiological questionnaires were designed to cover major potential risk factors, such as age, gender, ethnicity, contact with companion animals, livestock, or wild animals, bites from insects or animal, economical status, among other factors. Based on multivariate logistic regression, bloodstream infection with <i>B</i>. <i>henselae</i> or <i>B</i>. <i>clarridgeiae</i> was associated with cat contact (adjusted OR: 3.4, 95% CI: 1.1–9.6) or history of tick bite (adjusted OR: 3.7, 95% CI: 1.3–13.4). These risk factors should be considered during donor screening, as bacteremia by these <i>Bartonella</i> species may not be detected by traditional laboratory screening methods, and it may be transmitted by blood transfusion.</p></div

Univariate analysis of risk factors between blood donors with <i>Bartonella</i> infection detected by enrichment PCR, compared with uninfected subjects^a.

<p>Univariate analysis of risk factors between blood donors with <i>Bartonella</i> infection detected by enrichment PCR, compared with uninfected subjects<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004509#t001fn001" target="_blank">^a</a>.</p

<i>Bartonella</i> spp. Bacteremia in Blood Donors from Campinas, Brazil

<div><p><i>Bartonella</i> species are blood-borne, re-emerging organisms, capable of causing prolonged infection with diverse disease manifestations, from asymptomatic bacteremia to chronic debilitating disease and death. This pathogen can survive for over a month in stored blood. However, its prevalence among blood donors is unknown, and screening of blood supplies for this pathogen is not routinely performed. We investigated <i>Bartonella</i> spp. prevalence in 500 blood donors from Campinas, Brazil, based on a cross-sectional design. Blood samples were inoculated into an enrichment liquid growth medium and sub-inoculated onto blood agar. Liquid culture samples and Gram-negative isolates were tested using a genus specific ITS PCR with amplicons sequenced for species identification. <i>Bartonella henselae</i> and <i>Bartonella quintana</i> antibodies were assayed by indirect immunofluorescence. <i>B. henselae</i> was isolated from six donors (1.2%). Sixteen donors (3.2%) were <i>Bartonella</i>-PCR positive after culture in liquid or on solid media, with 15 donors infected with <i>B. henselae</i> and one donor infected with <i>Bartonella clarridgeiae</i>. Antibodies against <i>B. henselae</i> or <i>B. quintana</i> were found in 16% and 32% of 500 blood donors, respectively. Serology was not associated with infection, with only three of 16 <i>Bartonella</i>-infected subjects seropositive for <i>B. henselae</i> or <i>B. quintana</i>. <i>Bartonella</i> DNA was present in the bloodstream of approximately one out of 30 donors from a major blood bank in South America. Negative serology does not rule out <i>Bartonella</i> spp. infection in healthy subjects. Using a combination of liquid and solid cultures, PCR, and DNA sequencing, this study documents for the first time that <i>Bartonella</i> spp. bacteremia occurs in asymptomatic blood donors. Our findings support further evaluation of <i>Bartonella</i> spp. transmission which can occur through blood transfusions.</p></div

Flowchart of the culture and PCR-based procedures performed to determine <i>Bartonella</i> prevalence in 500 blood donors from Campinas, Brazil.

<p>Flowchart of the culture and PCR-based procedures performed to determine <i>Bartonella</i> prevalence in 500 blood donors from Campinas, Brazil.</p