Potential health-care associated respiratory syncytial virus in three referral Hospitals in Kenya, 2009-2011

Abstract

Background: Respiratory syncytial virus (RSV) is a major cause of community acquired severe respiratory illness in infants, immunocompromised individuals and the elderly. Limited information exists on the contribution of RSV in respiratory Hospital Associated Infection (rHAI) in developing countries. Objective: To characterize Respiratory Syncytial Virus in the three Kenyan referral setting as a potential contributor to respiratory hospital acquired infection. Methods: The study targeted all patients whose samples tested positive for RSV from the ongoing surveillance on healthcare associated respiratory infections. The study collected nasal and oropharyngeal samples from patients who developed new-onset axilla fever and influenza like illness, in patients who had been afebrile for at least three (3) days in the wards and tested them for different respiratory pathogens (Influenza A and B, Parainfluenza, Human metapneumovirus and adenovirus) alongside RSV. During this period A total of 37 samples tested RSV positive. These were characterized as RSV-A and -B using RT-PCR. Those that typed successfully were then sequenced in the attachment G protein and phylogenetically analyzed. Results: Of the 37 samples, 13(35%) were RSV A, 6 (16%) RSV B, 1 (3%) was AB and 17 (46%) did not type. Twenty out of the 37 attained the sequencing criteria and only seventeen gave successful sequences. Three RSV- A and 2 RSV-B sequenced samples from KNH were 100% identical in the G ectodomain sequences. One RSV-A specimen from MDH and one RSV-A positive from NNPGH had 100% identity. Three sequences from KNH clustered with high nucleotide sequence identity. Children below 2years were significantly more at risk of RSV than those aged 5years and above (aOR=0.21,p=0.012). Conclusions: The study inferred possibility of spread of RSV within the hospitals especially the paediatric ward. Any interventions to curb the spread should specifically target all children ≤ 2 years.