“…To date, several studies have estimated the incidence of IPD among persons with high-risk conditions such as sickle-cell anemia, HIV infection, chronic pulmonary diseases, cardiac diseases, alcoholism and/or smoking [6,7,[25][26][27][28]. According to systematic reviews, anatomic or functional asplenia, immunodeficiency and immunocompromising conditions are considered as major risk factors for IPD [6,29].…”