-Increased in the past two decades 66% have had received PPV
What is the 13 valent pneumococcal conjugate vaccine (PCV)?
-A vaccine for strep pneumococcal
-Protein carb (CHO) conjugate
-Induce a T cell independent response, children < 2years have poor response to CHO, protein component aids a T-cell dependent response, more effective vaccine ages <2, fragment of diphtheria toxin used as protein conjugate.
-Contains 13 serotypes: these 7 cover > 80% of S. pneumoniae for kids <ages 6, goal to vaccinate all kids under 2
What is the pneumococcal vaccine schedule?
-4 childhood shots of PCV at (2, 4, 6, 12-15 months)
-PCV booster or PPV for children older that 2 years old (2-6 years) which are certain high-risk groups
-Sickle cell anemia, HIV, chronic heart/lung
-More common among healthy children of certain racial or ethnic groups, such as alaska natives, native americans, and african-americans.
IPD-Invasive pneumoccoal disease in young children has declined due to vaccine
What is legionella pneumophila?
-Legionnaires disease acquired its name in 1976 when an outbreak of a pneumonia occurred among people attending a convention of american legion in Philadelphia.
-200th birthday, many elderly
-A week later 200 had mysterious pneumonia which killed 34 of them
-Several months of investigation resulted in identifying the agent as a bacterium that is present in natural moist environment (aquatic saprophyte)
What is the diagnosis of legionella pneumophilia?
Difficult before: the organism could not be cultured by common culturing techniques, grain stain did not work, it was possible to stain with Fluorescent Antibody stain (FAB)
Easier today: Sputum is best test. Culture in buffered charcoal yeast extract (BCYE), use FAB
What is the shape of legionella pneumophila?
Gram-negative slender pleomorphic rods
What modes of transmission are we concerned about today with Legionella?
10,000-15,000 cases occur each year in US, most sporadically
Aerosol transmission of Legionella occurs by way of: contaminated cooling towers, evaporative condensers and showers, humidifiers, respiratory therapy equipment, whirlpool spas, decorative fountains.
What are risks factors of legionella?
Patients with compromised pulmonary functions
Patients that are immunocompromised: transplant patients, elderly in hospital
25% of cases of hospital acquired
death could occur in 30% of cases
What unusual characteristics do we now know about the biology of this organism?
-The organism can live in moist environment for a long time: parasitize amoeba in water, survive in biofilms of pipe systems, within human lung macrophage and cause pneumonia
-Treatable disease with antibiotics but hard to diagnose. of the cases, only 1200-2200 reported, milder form of legionnaires this disease is called pontiac fever.
What are two names for the disease caused by mycoplasma pneumoniae?
-Primary atypical pneumonia
What are biological properties of m. pneumoniae?
Very small bacterium
Fastidious (hard to culture), fried egg colony morphology
-No PG in cell wall (atypical)
-Sterols in cell wall (atypical)
-Higher incidence of pneumonia in Military/college population
Why is ampicillin not used to treat walking pneumonia?
-No PG in wall means no penicillin sensitivity
-Coccoid or filamentous because no cell wall
How to diagnosis/treatment properties M. pneumoniae?
Difficult to diagnosis
based on symptoms, grows slowly in culture 2 weeks
Chest x-ray: diffused infiltrate not remarkable
Serological diagnosis: a variety of rapid tests based on indirect hemagglutination of erythrocytes or latex particles coated with M. pneumoniae antigens have been developed and some are commercially available
PCR: treatment long term with non penicillin family of drugs
What is chlamydia pneumoniae?
-Gram negative roundish irregular shape
-ER: elementary body
-RB: reticulate body
Where does chlamydia pneumoniae grow?
-Obligate intracellular pathogen that has a unique developmental cycle in mammalian host cells. Cant make own ATP, takes from host.
- Once inside phagocytic cells of lung (alveolar macrophages), it prevents fusion of phagosome and lysosome
What is the pathogenesis of chlamydia pneumoniae?
-Respiratory pathogen causes pneumonia, bronchitis, phargngitis, and sinusitis
-C. pneumonia cause 10% of all community acquired pneumonias
-Organism can make its way into the walls of various medium and large blood vessels, linger for years inducing the inflammation and immune reaction causing atherosclerosis leading to heart attacks and strokes
What is the treatment of c.pneumoniae?
Due to the intracellular nature, long term (weeks to months) antimicrobial treatment is needed
What is klebsiella pneumoniae?
-Encapsulated Gram negative rods found in normal flora of human mouth, skin, intestines
-Can cause bacterial lobar pneumonia, typically due to aspiration in alcoholics or people with compromised pulmonary function
-It is also an opportunistic pathogen more commonly causing hospital acquired lung, urinary tract and wound infections
How many of the pneumonia causing agents do we know?
- only 50% of agent cause pneumonia cases are known.