Figures
- Figure 1.
Pneumococcal diseases can be broadly divided into invasive and noninvasive disease. Invasive disease is diagnosed when Streptococcus pneumoniae is detected in normally sterile body fluids. Pneumonia can be invasive (bacteraemic) or noninvasive.
- Figure 2.
Annual costs (in € billion) associated with invasive pneumococcal disease in Europe [13].
- Figure 3.
Percentage of people by age group from 1950 and projected up to 2050. Data taken from [15].
Tables
- Table 1. Case fatality rate in patients hospitalised for invasive pneumococcal disease, 1952–2001
Period studied [ref.] Patients n Case fatality rate % 1952–1962 [8] 1130 13 1966–1995 [10] 4432 12 1995–1997 [9] 5837 12 1999–2001 [11] 730 ∼12# #: 90-day fatality in intensive care unit versus ward patients, with an average of the two rates ∼12%.
- Table 2. Summary of the complex changes in the immune system resulting in immunosenescence
Innate immunity Adaptive immunity ↑ inflammatory reactions Restricted T-cell repertoire ↑ numbers of natural killer cells ↓ naïve T-cell output ↓ antigen uptake and presentation ↑ number of effector T-cell ↓ phagocytic capacity and oxidative burst of macrophages Low-affinity antibody responses ↓ cytotoxic function ↓ B-cell production and defective isotype switching Data are taken from [17–20].
- Table 3. Summary of World Health Organization (WHO) and the Advisory Committee on Immunization Practices (ACIP) recommendations for pneumococcal polysaccharide and influenza vaccinations
WHO recommendations Pneumococcal polysaccharide vaccination Influenza vaccination Healthy elderly (>65 yrs of age), particularly those living in institutions Elderly individuals above a nationally defined age limit, irrespective of other risk factors Patients with chronic organ failure Residents of institutions for elderly people and the disabled Heart, lung, liver or kidney disease, diabetes mellitus and alcoholism Elderly, non-institutionalised individuals with chronic heart or lung diseases, metabolic disease including diabetes or renal disease, or immunodeficiencies Children >2 yrs old at high risk for disease (splenectomised children and sickle-cell disease) All individuals >6 months of age with any of the conditions listed above Patients with immunodeficiencies particularly those with functional or anatomical asplenia Other groups defined on the basis of national data and capacities, such as contacts of high-risk people, pregnant females, healthcare workers and others with key functions in society, as well as children 6–23 months of age Prevention of subsequent pneumococcal infection in patients recovering from proven or assumed pneumococcal pneumonia ACIP recommendations Pneumococcal polysaccharide vaccination Influenza vaccination Adults aged ≥65 yrs
Patients with chronic illnessPersons aged ≥50 yrs Chronic cardiovascular, pulmonary and liver disease Adults and children with chronic disorders Diabetes mellitus Pulmonary (including asthma) and cardiovascular systems (except hypertension), renal, hepatic, haematological or metabolic disorders (diabetes mellitus) Alcoholism Immunocompromised adults and children, including HIV-infected persons and users of immunosuppressive medications Cerebrospinal fluid leak Children and teenagers (6 months to 18 yrs of age) receiving long-term aspirin therapy Persons aged 2–64 yrs with physical or functional asplenia Females who will be pregnant during the influenza season Immunocompromised persons aged ≥2 yrs including those with HIV infection, leukaemia, lymphoma, Hodgkin's disease, multiple myeloma, generalised malignancy, chronic renal failure or nephritic syndrome; those receiving immunosuppressive chemotherapy (including corticosteroids) and those who have received an organ or bone marrow transplant Residents of nursing homes and other chronic care facilities Persons aged 2–64 yrs living in special environments or social settings Healthy children aged 6–59 months Persons who live with, or care for, persons at high risk for flu-related complications Adults and children who have any condition that can compromise respiratory function or the handling of respiratory secretions or that can increase the risk for aspiration (e.g. cognitive dysfunction, spinal cord injuries, seizure disorders or other neuromuscular disorders) Data are taken from [22–26].
- Table 4. Comparison of risk-based and age-based vaccination strategies
Age-based strategies At-risk strategies Target group easy to access High-risk people often difficult to access (e.g. socially disadvantaged) Infrastructures usually exist to administer vaccines Responsibility for vaccination lies with different healthcare professionals Community protection (herd effect) is possible Difficult to establish a herd effect Generally higher levels of vaccine uptake achieved Unlikely to achieve high levels of vaccine uptake - Table 5. Association between bacterial load (as assessed using real-time PCR techniques) and clinical outcome
Low bacterial load# High bacterial load¶ OR (95% CI) <103 copies per mL ≥103 copies per mL Rapid radiological spread 1.5 25.9 22.75 (3.36–148.37) Acute respiratory distress syndrome 1.5 18.5 14.77 (2.12–99.49) Septic shock 9.1 44.4 8.00 (2.65–24.12) Need for mechanical ventilation 4.5 33.3 10.50 (2.74–39.63) Hospital case fatality rate 6.1 25.9 5.43 (1.52–19.24) Data are presented as the percentage of patients for each outcome, unless otherwise stated. #: n=66; ¶: n=27. Data are taken from [41].
- Table 6. Influence of pneumococcal serotype on outcome in adults with bacteraemic pneumonia
Invasive potential Other serotypes High Low Need for vasopressor 25.8 44.8 34.0 Mechanical ventilation 12.9 25.6 13.8 Severe pneumonia 26.8 51.2 34.9 30-day case fatality rate 3.2 25.6 7.3 Data are presented as %. High invasive disease potential serotypes included serotypes 1, 5 and 7F; low invasive disease potential serotypes included 3, 6A, 6B, 8, 19F and 23F. Data taken from [55].
Vol 21 Issue 123
Table of Contents
The remaining challenges of pneumococcal disease in adults
