Pneumonia and Invasive Pneumococcal Diseases: The Role of Pneumococcal Conjugate Vaccine in the Era of Multi-Drug Resistance

Abstract

Streptococcus pneumoniae related diseases are a leading cause of morbidity and mortality, especially in children and in the elderly population. It is transmitted to other individuals through droplets and it can spread to other parts of the human host, causing a wide spectrum of clinical syndromes, affecting between 10 and 100 cases per 100,000 people in Europe and the USA. In order to reduce morbidity and mortality caused by this agent, pneumococcal vaccines have been developed over the years and have shown incredible effectiveness in reducing the spread of this bacterium and the development of related diseases, obtaining a significant reduction in mortality, especially in developing countries. However, considerable problems are emerging mainly due to the replacement phenomenon, multi-drug resistance, and the high production costs of conjugated vaccines. There is still a debate about the indications given by various countries to different age groups; this is one of the reasons for the diffusion of different serotypes. To cope with these problems, significant efforts have been made in the research field to further improve vaccination serotypes coverage. On the other hand, an equally important commitment by health care systems to all age group populations is needed to improve vaccination coverage.

The impact of introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) on pneumococcal carriage in Nigeria

“…[1] PCV use has also substantially reduced hospital visits from pneumococcal otitis media and antibiotic use and has the potential to reduce antimicrobial resistance. [2][3][4] Nonetheless, Streptococcus pneumoniae (the pneumococcus) remains a leading cause of pneumonia and invasive diseases (meningitis, bacteraemic pneumonia and bacteraemia). [1] In 2015, pneumococcal disease still caused approximately 300,000 deaths among children aged 1-59 months globally, and over 50% of these deaths occurred in the African sub-region.…”

“…adjusted for symptoms of upper respiratory tract infection in past two weeks, living with≥2 under-fives, and age-standardised to age distribution of study sites; 2 prevalence ratios across all surveys from date of PCV10 introduction to date of swabbing coded as a single time variable to obtain estimate of prevalence ratio per year; 3 Five surveys (2016-2020);4 Four surveys (2017-2020); 5 prevalence ratio comparing final survey in each site to the 1 st survey.…”

Triosephosphate isomerase of Streptococcus pneumoniae is released extracellularly by autolysis and binds to host plasminogen to promote its activation

“…Infections caused by Streptococcus pneumoniae are prevalent worldwide, with particularly high morbidity and mortality in children and the elderly [1]. In 2005, the World Health Organization estimated that 1.6 million deaths per year were caused by S. pneumoniae [1].…”

“…Infections caused by Streptococcus pneumoniae are prevalent worldwide, with particularly high morbidity and mortality in children and the elderly [1]. In 2005, the World Health Organization estimated that 1.6 million deaths per year were caused by S. pneumoniae [1]. S. pneumoniae is a commensal bacterium that settles in the human nasopharynx, causing not only noninvasive diseases such as otitis media, sinusitis, and pneumonia, but also invasive and life-threatening diseases such as bacteremia, sepsis, and meningitis.…”

Persistence of Pneumococcal Serotype 3 in Adult Pneumococcal Disease in Hong Kong

“…Studies have revealed that childhood immunisation has led to reduced adult pneumococcal disease through herd effects [ 5 ]. However, this is less marked in populations with risk factors [ 6 ], and disease burden based on IPD surveillance is often underestimated.…”