title: Weather parameters and nosocomial bloodstream infection: a case-referent study.
abstract: OBJECTIVE To evaluate if temperature and humidity influenced the etiology of bloodstream infections in a hospital from 2005 to 2010. METHODS The study had a case-referent design. Individual cases of bloodstream infections caused by specific groups or pathogens were compared with several references. In the first analysis, average temperature and humidity values for the seven days preceding collection of blood cultures were compared with an overall "seven-days moving average" for the study period. The second analysis included only patients with bloodstream infections. Several logistic regression models were used to compare different pathogens and groups with respect to the immediate weather parameters, adjusting for demographics, time, and unit of admission. RESULTS Higher temperatures and humidity were related to the recovery of bacteria as a whole (versus fungi) and of gram-negative bacilli. In the multivariable models, temperature was positively associated with the recovery of gram-negative bacilli (OR = 1.14; 95%CI 1.10;1.19) or Acinetobacter baumannii (OR = 1.26; 95%CI 1.16;1.37), even after adjustment for demographic and admission data. An inverse association was identified for humidity. CONCLUSIONS The study documented the impact of temperature and humidity on the incidence and etiology of bloodstream infections. The results correspond with those from ecological studies, indicating a higher incidence of gram-negative bacilli during warm seasons. These findings should guide policies directed at preventing and controlling healthcare-associated infections.
authors.forename: Silvia Maria
authors.initials: SM
authors.lastname: Caldeira
authors.forename: Antonio Ribeiro da
authors.initials: AR
authors.lastname: Cunha
authors.forename: Renata Tamie
authors.initials: RT
authors.lastname: Akazawa
authors.forename: Rayana Gonçalves
authors.initials: RG
authors.lastname: Moreira
authors.forename: Lenice do Rosário de
authors.initials: Ldo R
authors.lastname: Souza
authors.forename: Carlos Magno Castelo Branco
authors.initials: CM
authors.lastname: Fortaleza
mesh_terms: D016470:Bacteremia / Q000382:microbiology*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D003428:Cross Infection / Q000382:microbiology*; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D006813:Humidity / Q000009:adverse effects*; D014887:Weather
references.citation: Infect Control Hosp Epidemiol. 1995 Oct;16(10):590-4
references.pmid: 8568204
references.citation: PLoS One. 2014;9(3):e91105
references.pmid: 24599500
references.citation: Annu Rev Public Health. 2007;28:127-43
references.pmid: 17222079
references.citation: Burns. 2007 Dec;33(8):1008-14
references.pmid: 17996555
references.citation: J Hosp Infect. 2008 Apr;68(4):285-92
references.pmid: 18329137
references.citation: Am J Infect Control. 2008 Jun;36(5):309-32
references.pmid: 18538699
references.citation: J Hosp Infect. 2008 Jul;69(3):204-19
references.pmid: 18513830
references.citation: Infect Control Hosp Epidemiol. 2008 Oct;29(10):901-13
references.pmid: 18808340
references.citation: Infect Control Hosp Epidemiol. 2008 Dec;29(12):1124-31
references.pmid: 19031546
references.citation: Infect Control Hosp Epidemiol. 2010 Nov;31(11):1154-9
references.pmid: 20849274
references.citation: J Hosp Infect. 2010 Dec;76(4):311-5
references.pmid: 20884080
references.citation: Lancet. 2011 Jan 15;377(9761):228-41
references.pmid: 21146207
references.citation: Clin Infect Dis. 2011 May;52(9):1138-43
references.pmid: 21467020
references.citation: Microbes Environ. 2011;26(2):101-12
references.pmid: 21502736
references.citation: PLoS One. 2011;6(9):e25298
references.pmid: 21966489
references.citation: Am J Epidemiol. 2011 Nov 15;174(10):1101-7
references.pmid: 21940800
references.citation: Clin Microbiol Infect. 2012 Oct;18(10):934-40
references.pmid: 22784293
references.citation: Clin Microbiol Infect. 2012 Oct;18(10):927-33
references.pmid: 22958212
references.citation: Infect Control Hosp Epidemiol. 2012 Oct;33(10):1051-2
references.pmid: 22961027
references.citation: PLoS One. 2012;7(12):e52342
references.pmid: 23300645
references.citation: Curr Opin Infect Dis. 2013 Aug;26(4):338-44
references.pmid: 23743816
references.citation: Int J Infect Dis. 2013 Sep;17(9):e757-61
references.pmid: 23639485
references.citation: Infect Control Hosp Epidemiol. 2014 Jan;35(1):85-8
references.pmid: 24334804
references.citation: Clin Infect Dis. 1999 Nov;29(5):1133-7
references.pmid: 10524953