Epidemiology of viral respiratory tract infections in a prospective cohort of infants and toddlers attending daycare

J Clin Virol. 2010 Sep;49(1):16-20. doi: 10.1016/j.jcv.2010.06.013. Epub 2010 Jul 21.

Abstract

Background: The epidemiology of respiratory tract infections (RTIs) in a daycare cohort has not been explored using molecular techniques.

Objectives: (1) Determine the overall incidence of RTIs in a daycare cohort using real-time reverse transcriptase polymerase chain reaction (RT-PCR). (2) Determine the relative incidence and impact of specific respiratory viruses, and characterize and compare clinical features associated with these pathogens.

Study design: In this prospective cohort study conducted from February 2006 to April 2008, nasal swabs were obtained from symptomatic children ages 0-30 months enrolled in fulltime daycare. RT-PCR was performed to detect respiratory syncytial virus (RSV), human metapneumovirus (MPV), influenza (Flu) viruses A and B, parainfluenza (PIV), adenovirus (AdV), human coronaviruses (CoV) and rhinovirus (RhV). Symptom diaries were completed for each illness.

Results: We followed 119 children (mean age 10 months; range 2-24 months) for 115 child years. The mean annual incidence of RTI per child was 4.2 the first year and 1.2 the second year of the study. At least 1 virus was identified in 67% RTIs. Co-infections were common (27% RTIs), with RhV, CoV, and AdV the most common co-pathogens. PIV was identified in 12% of RTIs with a high incidence of PIV4. The viruses with the greatest impact on our population were RSV, RhV and AdV.

Conclusions: Using molecular techniques, viruses were identified in approximately twice as many RTIs as previously reported in a daycare cohort. Infections with newly identified viruses, such as HMPV and CoV subtypes were less frequent and severe than infections with RSV, AdV and RhV.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Adenoviridae / isolation & purification
  • Child Day Care Centers / statistics & numerical data*
  • Child, Preschool
  • Cohort Studies
  • Female
  • Humans
  • Incidence
  • Infant
  • Infant, Newborn
  • Male
  • Prospective Studies
  • Respiratory Syncytial Virus, Human / genetics
  • Respiratory Syncytial Virus, Human / isolation & purification
  • Respiratory Tract Infections / epidemiology*
  • Respiratory Tract Infections / virology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Rhinovirus / genetics
  • Rhinovirus / isolation & purification
  • Virus Diseases / epidemiology*
  • Virus Diseases / virology*