NasopharyngealStaphylococcus aureuscolonization among HIV-infected children in Addis Ababa, Ethiopia: Antimicrobial susceptibility pattern and association withStreptococcus pneumoniaecolonization

Abstract

AbstractBackgroundStaphylococcus aureusandStreptococcus pneumoniaeare common inhabitants of the nasopharynx of children. HIV-infected children have higher risk of invasive diseases caused by these pathogens. With widespread use of pneumococcal conjugate vaccines and the emergence of methicillin-resistantS aureus, the interaction between S.aureusandS. pneumoniaeis of a particular significance. We sought to determine the magnitude of colonization by methicillin-sensitive and -resistant S.aureusand colonization byS. pneumoniae; associated risk factors and antimicrobial susceptibility pattern among HIV-Infected children in Addis Ababa, Ethiopia.MethodA prospective observational study was conducted in 183 HIV-infected children at ALERT hospital Addis Ababa, Ethiopia from September 2016 to August 2018. S.aureusandS. pneumoniaewere identified using standard bacteriological techniques, antimicrobial susceptibility testing was performed on S.aureusand screening for methicillin resistance was carried out by amplifying themecAgene. Risk factors were analyzed by using binary logistic regression.ResultsThe prevalence of nasopharyngealS. aureus, MRSA andS. pneumoniaecolonization were 27.3%, 2.7% and 43.2% respectively. Multivariable analysis indicated an inverse association betweenS. aureusand S.pneumoniaenasopharyngeal colonization (aOR, 0.49; CI, (0.24, 0.99);p= 0.046). The highest level of resistance in both methicillin sensitiveS. aureus(MSSA) and MRSA was observed against tetracycline.ConclusionsWe found an inverse association betweenS. aureusandS. pneumoniaecolonization among HIV-infected children. Continued assessment of the impact of pneumococcal conjugate vaccines and anti-retroviral therapy on nasopharyngeal bacterial ecology is warranted.