Introduction

AF designed the study, participated in data collection and analysis, performed statistical analysis and wrote the paper. AL participates in study design, data collection and analysis, performed statistical analysis and participated in writing. JM, SD, JMC, AM and CEL participated in patients' care and clinical data collection and analysis. CP participated in study design, data collection and analysis. AGM performed virology analysis. MB participated in study design, data collection and analysis and writing. All authors contributed to writing of the paper.

No abstract