title: Influenza and other respiratory viruses in three Central American countries.
abstract: BACKGROUND
  Despite the disease burden imposed by respiratory diseases on children in Central America, there is a paucity of data describing the etiologic agents of the disease.
  
  
  OBJECTIVE
  To analyze viral etiologic agents associated with influenza-like illness (ILI) in participants reporting to one outpatient health center, one pediatric hospital, and three general hospitals in El Salvador, Honduras, and Nicaragua Material &
  
  
  METHODS
  Between August 2006 and April 2009, pharyngeal swabs were collected from outpatients and inpatients. Patient specimens were inoculated onto cultured cell monolayers, and viral antigens were detected by indirect and direct immunofluorescence staining.
  
  
  RESULTS
  A total of 1,756 patients were enrolled, of whom 1,195 (68.3%) were under the age of 5; and 183 (10.4%) required hospitalization. One or more viral agents were identified in 434 (24.7%) cases, of which 17 (3.9%) were dual infections. The most common viruses isolated were influenza A virus (130; 7.4% of cases), respiratory syncytial virus (122; 6.9%), adenoviruses (63; 3.6%), parainfluenza viruses (57; 3.2%), influenza B virus (47; 2.7% of cases), and herpes simplex virus 1 (22; 1.3%). In addition, human metapneumovirus and enteroviruses (coxsackie and echovirus) were isolated from patient specimens.
  
  
  CONCLUSIONS
  When compared to the rest of the population, viruses were isolated from a significantly higher percentage of patients age 5 or younger. The prevalence of influenza A virus or influenza B virus infections was similar between the younger and older age groups. RSV was the most commonly detected pathogen in infants age 5 and younger and was significantly associated with pneumonia (p < 0.0001) and hospitalization (p < 0.0001).
  
  
  CONCLUSIONS
  Genetic analysis of influenza isolates identified A (H3N2), A (H1N1), and B viruses. It also showed that the mutation H274Y conferring resistance to oseltamivir was first detected in Honduran influenza A/H1N1 strains at the beginning of 2008. These data demonstrate that a diverse range of respiratory pathogens are associated with ILI in Honduras, El Salvador, and Nicaragua. RSV infection in particular appears to be associated with severe disease in infants in the region.
authors.affiliation: US Naval Medical Research Center Detachment, Lima, Perú. alberto.laguna@med.navy.mil
authors.forename: Victor A
authors.initials: VA
authors.lastname: Laguna-Torres
authors.forename: José F
authors.initials: JF
authors.lastname: Sánchez-Largaespada
authors.forename: Ivette
authors.initials: I
authors.lastname: Lorenzana
authors.forename: Brett
authors.initials: B
authors.lastname: Forshey
authors.forename: Patricia
authors.initials: P
authors.lastname: Aguilar
authors.forename: Mirna
authors.initials: M
authors.lastname: Jimenez
authors.forename: Eduardo
authors.initials: E
authors.lastname: Parrales
authors.forename: Francisco
authors.initials: F
authors.lastname: Rodriguez
authors.forename: Josefina
authors.initials: J
authors.lastname: García
authors.forename: Ileana
authors.initials: I
authors.lastname: Jimenez
authors.forename: Maribel
authors.initials: M
authors.lastname: Rivera
authors.forename: Juan
authors.initials: J
authors.lastname: Perez
authors.forename: Merly
authors.initials: M
authors.lastname: Sovero
authors.forename: Jane
authors.initials: J
authors.lastname: Rios
authors.forename: María E
authors.initials: ME
authors.lastname: Gamero
authors.forename: Eric S
authors.initials: ES
authors.lastname: Halsey
authors.forename: Tadeusz J
authors.initials: TJ
authors.lastname: Kochel
mesh_terms: D000256:Adenoviridae / Q000302:isolation & purification; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002489:Central America; D002648:Child; D002675:Child, Preschool; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009980:Influenza A virus / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000821:virology; D010802:Phylogeny; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification*; D012141:Respiratory Tract Infections / Q000821:virology*