Infectious Disease Flashcards
Name three toxin mediated diseases caused by staph aureus
scalded skin syndrome
toxic shock syndrome
staphylococcal epidermal necrolysis
What is the D test?
determines if ther is macrolide inducible clindamycin resistance. Must be done if organism is sensitive to clindamycin and resistant to erythromycin.
If positive D test, do not treat with clindamycin
Treatment of boil or abscess if a mild, moderate vs. severe infection.
Mild: can often only be treated with incision and drainage. If oral antibiotic: TMP/SMX (if strep unlikely), clindamycin or doxycycline if > 8 years old
Moderate: have fever but otherwise healthy. Prescribe oral antibiotic as above
Severe: toxic appearing, sick, immunocompromised. Admit with IV antibiotic, vancomycin.
If critically ill, consider vancomycin and nafcillin
What infection control measures are necessary for highly resistant staphylococcus aureus?
isolate patient to private room
gown and gloves
wash hands with soap and water and or alcohol rub
dedicated items (stethoscope)
face mask and eye protection if doing something that makes splashes
consult cdc, health department before dc or transfer
What complications should you suspect if a child has S. aureus bacteremia?
osteomyelitis, endocarditis, thromboembolism, empyema more likely to occur with pneumonia
What are the symptoms and the cause of toxic shock syndrome?
TSS toxin-1
generalized red skin, hypotension, fever, diarrhea and multiorgan system involvement, > 3 systems. Desquamation of hands, feet occurs 1-2 weeks after illness
Treatment of toxic shock syndrome
fluids, nafcillin or vancomycin if MRSA and clindamycin which decreases toxin production
blood cultures are usually negative
What causes staphylococcal scalded skin syndrome and what are the symptoms
exfoliative toxins A and B
Fever, minimal friction applied to skin results in removal of superficial layers of epidermis : Nikolsky sign
extensive sloughing can occur though this is less likely to occur in older children
Complications to watch out for with staphylococcal scaled skin syndrome?
dehydration and superficial infection due to extensive skin sloughing
what causes Staphylococcus aureus food poisoning? What is the timing of symptom onset and what are the symptoms?
Preformed enterotoxin.
In < 4-6 hours after eating suspect food
self limited abrupt onset nausea, vomiting, diarrhea, abdominal cramps
What is the most common cause of catheter related bacteremia?
S. epidermidis
Staph epidermidis is usually always resistant to what antibiotic?
methicillin
Treatment for s. epidermidis
vancomycin +/- rifampin +/- gentamycin
S. saprophyticus usually causes what type of infection? How should it be treated
UTI in adolescent females.
TMP/SMX, nitrofurantoin, cephalothin
No 3rd gen cephalosporins, not effective
When is staph epi a contaminate and when is it not?
Contaminate in single blood culture with out risk factors or indwelling device
True infection in those who are immunocompromised, have indwelling catheter, NICU baby
coagulase negative staph most common cause of late onset sepsis in preterm infants esp. those < 1500 g
Who is at increased risk for Strep pneumoniae infections
Asplenic Very old or very young those with hypogammaglobulinemia HIV infection cochlear implants Alaska natives and native americans < 2 congenital immunodeficiency chronic disease (cardiac, pulm, renal) CSF leals DM immunosuppressive therapy
What is the most common cause of otitis media and how do you treat?
Strep pneumoniae
High dose amoxicillin 80-90 mg/kg/day
if no response in 48 hours broaden to Augmentin or 2nd or 3rd generation cephalosporin
When can an otitis media be observed?
children 6months to 2 years with unilateral disease and no otorrhea. > 2 years unilateral or bilateral with out otorrhea
must have close follow up and start antibiotics if no improvement in 24-72 hours
What is the antibiotic choice for strep pneumoniae due to possible penicillin resistance?
For bacteremia: ceftriaxone or cefotaxime until susceptibility is known
Meningitis: ceftriaxone, cefotaxime and vancomycin
Antibiotic recommendations for otitis media for those who are penicillin allergic?
cephalosporin, clindamycin, doxycycline (adolescents)
What diseases are caused by group A strep or strep pyogenes
pharyngitis impetigo, erysipelas, cellulitis scarlet fever rheumatic fever streptococcal toxic shock syndrome acute glomerulonephritis
What clinical findings make streptococcal pharyngitis more likely.
Temp > 100
tender cervical lymphadenopathy
exudative tonsils
If child > 2 years and has cough, rhinorrhea etc likely viral
In those < 2, they have thick purulent nasal discharge, low grade fever and decreased feeding
How is streptococcal pharyngitis diagnosed
rapid strep throat testing
if negative send culture
may wait on culture results before giving antibiotics as long as antibiotics are started within 9 days of infection to prevent rheumatic fever
What are the complications of streptococcal pharyngitis
otitis media, sinusitis, cervical lymphadenitis, peritonsillar/retropharyngeal abscess
rheumatic fever, glomerulonephritis
what causes scarlet fever and what is the presentation
streptococcal pyrogenic exotoxins (SPE A, B, C and F)
fine sand paper rash that starts on neck and upper chest and spreads
pastia lines in flexor creases, circumoral pallor
Impetigo diagnosis and complications
Vesicles that break open and ooze making a honey colored crust. Can lead to glomerulonephritis
Clinical features of erysipelas
strep infection in deeper layers of skin, to the dermis. Skin is erythematous and tender to touch with a well demarcated line
Complications of cellulitis from streptococcal infection
necrotizing fasciitis- destruction from infection down to subcutaneous tissue. Requires surgical debridement, IV penicillin and clindamycin.
recent / concurrent varicella infection is a risk factor
can result in post-strep glomerulonephritis
Treatment of strep pyogenes if penicillin allergic
cephalexin, or other cephalosporin, erythromycin or azithromycin if allergic to both penicillin and cephalosporins
Treatment recommendations for those with recurrent strep infections.
These individuals are thought to be carriers and antibiotics are usually not indicated except:
local outbreak of acute rheumatic fever or post strep glomerulonephritis
Outbreak in a closed community
family history of acute rheumatic fever
multiple (ping-pong) episodes of pharyngitis in a family despite appropriate antibiotics
can use clindamycin to try to irradiate carrier state
What are the differences in timing in the two causes of post-strep hematuria.
Ig A nephropathy < 5 days
glomerulonephritis: 10-21 days
What types of infection and who is most susceptible to Streptococcus agalactiae, Group B strep
bacteremia, meningitis, pneumonia
infants
Things to know about early onset Group B strep
occurs in 7 days of birth
obstetric complications and premature birth are common
septicemia > pneumonia > meningitis
Things to know about late onset Group B strep
Onset is after 7 days to 3 months
bacteremia with out a focus is most common presentation followed by meningitis
osteomyelitis
cellulitis-adenitis syndrome (bacteremic and require LP but often well appearing
Diagnosis and treatment of Group B strep
blood and CSF culture
ampicillin and gentamycin
once GBS is known pathogen can use ampicillin or penicillin G
Repeat
Most common cause of endocarditis in children
strep viridans
majority have underlying congenital heart defect or had rheumatic fever
cause of bacteremia in neutropenic patients
Name two species of enterococcus and the three types of infection it usually causes
E. faecalis and E. faecium
UTI, polymicrobial abdominal infections, bacteremia
What is the cause of enterococcus infection in an infant, symptoms and treatment
usually nosocomial in those with catheters or NEC
bradycardia, fever, apnea, abdominal distension
resistant to cephalosporins, penicillin and aminoglycosides and some even to vancomycin
if sensitive: aminoglycoside (gentamycin) plus ampicillin or vancomycin.
sensitivity testing important
Who is at risk for listeria monocytogenes
decreased immunity like transplant (renal), immunodeficiency, lymphoma, leukemia, neonates, pregnant women
What is infant listeria infection associated with and how is it treated
maternal amnioitis, brown stained amniotic fluid, preterm birth, pneumonia, septicemia and erythematous papular rash “granulomatosis infantisepticum”
Gram positive rod-can appear like diptheroids
ampicillin and an aminoglycoside (gentamycin)
use vancomycin or TMP/SMX if allergic to penicillin
use high dose ampicillin for meningitis plus aminoglycoside
What organism causes diptheria
corynebacterium diptheriae
Symptoms of diptheria
upper respiratory infection with gray-white pharyngeal membrane, hoarseness, sore throat, and low fever ( < 101) conjunctivitis and bull neck
laryngotracheobronchial diptheria results in hoarsenes, stridor and respiratory compromise
nasal diptheria more common in younger children with a profuse, mucoid grayish discharge
What are the toxic manifestations of diptheria
myocarditis with arrhythmia
proteinuria, cylindruria or microscopic hematuria
isolated peripheral neuropathy and Guillain-Barre like syndrome
Treatment for diptheria
equine antitoxin
erythromycin 2nd choice is penicillin
after recovery should be vaccinated
What is Corynebacterium jeikeium associated with
neutropenic patients and bone marrow transplant
often catheter related infections
must treat with vancomycin and must remove catheter
Type of anthrax and clinical manifestations of bacillus anthracis
cutaneous, GI and pulmonic
painless papule and vesiculates and forms a painless ulcer than painless black eschar
gram negative rod
Treatment for bacillus anthracis.
ciprofloxacin or doxycycline (penicillin only if susceptible)
same antibiotic for prophylaxis after potential exposure
What two types of illness dose Bacillus cereus cause
emesis type: short incubation 1-6 hours due to preformed heat stable toxin (fried rice at room temperature)
diarrhea type: 8-16 hour incubation, heat-labile enterotoxin production in the GI tract
gram positive rod
Presentation of clostridium difficile
antibiotic associated colitis, and occur up to 3 weeks after cessation of antibiotics
can be community acquired so consider in someone with prolonged bloody diarrhea
Diagnosis and treatment of clostridium difficile
C. diff toxin in stool, PCR assay
only test those who are symptomatic, carriage in young children is common and not pathogenic
10-14 days of oral metronidazole
may repeat for 1st recurrence
any further recurrence should be treated with oral vancomycin
Most common cause of gas gangrene and treatment
C. perfringens
PCN
if allergic: clindamycin, metronidazole, meropenem
What are the clinical forms of clostridium tetani. What causes the disease?
due to a neurotoxin produced
generalized: widespread distribution of toxin
Local: with toxin only near portal of entry
cephalic: distribution of the cranial nerves
neonatal: generalized
How does tetanus present
How does neonatal tetanus present
Incubation of 3-21 days, wound appears inconsequential
increasing stiffness of muscles of the jaw, neck and large muscles of back and lower extremities
spasms in response to loud nose, touch, light that cause paroxysmal contraction
risus sardonicus
neonatal forum: 4-14 days of life, child with excessive crying and unable to suck, trismus, contractions, spasms and seizures
Treatment of tetanus
quite stimulus free environment
neurologic blocking agents, mechanical ventilation
human tetanus immunoglobulin and metronidazole
When does a child need tetanus vaccine after an injury
wound is dirty and child has had < 3 immunizations or history is unknown: vaccine and tetanus immunoglobulin
wound is clean and immunizations are up to date, < 10 years - no treatment
wound is dirty and immunization are up to date in last 5 years - no treatment
If dirty wound and last vaccine > 5 years, clean wound with Tdap > 10 years or clean wound and unknown vaccination - need vaccine
Name the gram stain and clinically significant serogroups of Neisseria meningitidis. At what ages is infection most common?
Gram negative diplococcus
A, W-135, C, Y and B
children < 2 and then 15-19 year olds, leading cause of meningitis
How does meningococcus present?
fever, hypotension, diffuse purpuric lesions and DIC.
Who is prone to meningococcemia and therefore what should be tested?
terminal complement deficiency or those deficient in properdin.
CH50 or CH100 assay
Treatment for meningococcus?
Penicillin G or if allergic:
3rd generation cephalosporin
if allergic to both, meropenem and chloramphenicol
Sequela of meningococcemia?
hearing loss, neurologic disability, digit or limb amputation. skin scarring, renal failure
Discuss who should receive prophylaxis and what they should receive
household, day care (anyone attending daycare with the child in the last 7 days) and close intimate contacts (who you live with) and if you sit next to someone on a plane for more than 8 hours.
Give rifampin or IM ceftriaxone (preferred if pregnant)
Give prophylaxis regardless of immunization status
For health care workers, only if there was direct contact with oral secretions (intubation, mouth to mouth)
When does Gonococcal ophthalmia occur most commonly and how does it present.
mostly occurs in the newborn period as the infant passes through in infected birth canal.
2-7 days after delivery with bloody green or serosanguinous discharge
Discuss timeline of other possible eye infections during the neonatal period.
First 48 hours is likely due to chemical reaction from eye drops given at birth (1% silver nitrate, 0.5% erythromycin
7-14 days is more likely chlamydia
What is the management of an infant with gonococcal ophthalmia
blood culture and lumbar puncture, eval for disseminated infection
Ceftriaxone 50 mg/kg IM or IV x1 though many receive more antibiotics while awaiting negative blood culture
Describe the stages of pertussis
catarrhal: mild respiratory tract infection
paroxysmal: paroxysms of cough with inspiratory whoop
convalescent: symptoms gradually improve duration of 6-10 weeks
What is the diagnosis and treatment of pertussis. Who gets prophylaxis?
culture of PCR of nasopharyngeal secretions
elevated WBC with an lymphocytosis in children is suggestive (not adolescents)
If > 1 month treat with azithromycin, erythromycin, clarithromycin
TMP/SMX if macrolide allergic
if < 1 month- azithromycin
same medications for chemo prophylaxis for daycare and household contacts
What is the gram stain for Moraxella catarrhalis, what infections does it cause and how do you treat it?
gram negative diplococcus
Otis media
rarely bacteremia or bronchopulmonary infections
100% make beta lactamase. So….
treat with augmentin, cefuroxime, cefprozil, cefpodoxime, azithromycin, TMP/SMX
Gram stain for pseudomonas and what type of clinical situations should make you consider it as a possible pathogen?
Gram negative rod with a single flagellum
cystic fibrosis, nail puncture wound though a shoe, osteomyelitis and endocarditis in IV drug user, bacteremia in burn patients, chronic Otis externa. Immunocompromised
Hot tub rash
ecthyma gangrenosum (round indurated black lesion with central ulceration)
treatment of pseudomonas
pip-tazo, cefepime, aminoglycides, quinolones, imipenem
What illnesses does Salmonella usually cause. What is the gram stain?
gram negative bacilli that are generally motile
diarrhea
rarely meningitis, bone infections (sickle cell)
How do you treat salmonella
treatment increases risk of a carrier state and does not decrease symptoms. If uncomplicated gastroenteritis, no antibiotics.
Treat is child < 3, immunocompromised with 3rd generation cephalosporin
Describe typhoid fever symptoms and treatment
fever, leukopenia, rose spots (angiomas)
blood culture is only 60% sensitive, bone marrow or bile culture is more likely to be diagnostic.
3rd generation cephalosporin, ampicillin, TMP/SMX, quinolones.
Carrier state without gallstones (typhi likes to hide there) can be cleared with 4 weeks of ciprofloxacin
In what situations dose shigella occur?
day care, crowed conditions or institutions, native American reservations. Children 1-4 during July and October.
Lots of person to person transmission
What are the symptoms of shigella
Incubation 24-48 hours, fever, malaise, decreased appetite, vomiting, headache, diarrhea.
diarrhea is watery, small with mucus and or blood with lower abdominal cramps
Seizures in infants
rectal prolapse, pseudomembranous colitis, HUS,
Treatment of shigella and when can a child return to daycare after illness
Antibiotics shorten disease, treat those with severe disease, immunocompromised
ceftriaxone azithromycin
cannot return to daycare until more than 24 hours with out diarrhea and negative stool cultures
Gram stain of E.coli
gram negative rod
lactose-fermenting
name 5 phenotypes of E. coli causing diarrhea
ePec: enteroPathogenic: acute diarrhea in infants
eTec: enteroToxigenic: watery Travelers diarrhea
eIec: enteroInvasive: diarrhea and fever
eHec: enteroHemorrhagic: hemorrhagic colits and HUS
eAec: enteroAggrefative: persistent diarrhea in children in developing countries
Symptoms and treatment of enterohemorrhagic E. coli.
bloody diarrhea, hemorrhagic colitis, hemolytic uremic syndrome (kidney failure, thrombocytopenia with purpura and hemolytic anemia)
Do not give antibiotics.
Can not return to daycare until 2 negative stool cutlures after diarrhea has resolved.
Who is most at risk for H. influenza meningitis and what are the symptoms?
infants < 1 month
seizure, petechial rash, buccal cellulitis
What are some of the complications of H. influenza meningitis?
hearing loss
subdural empyema, brain infarcts, cerebritis, ventriculitis, brain abscess and hydrocephalus, intellectual disability
Treatment for H. influenza meningitis
Ceftriaxone or cefotaxime
dexamethasone to decrease incidence of hearing loss and neurologic sequelae
Describe the presentation of epiglottitis due to H. influenza
high fever, dysphagia, drooling, tripod position to breath
cherry red epiglottitis
Do not try to examine the uncooperative child unless ready to secure airway
What organism is buccal cellulitis associated with and what does it look like?
H. influenza and usually is bacteremic,
palpable on both sides of the cheek and purplish in color
What is now the most common etiology for bacteremic periorbital cellulitis?
Common cause of preseptal cellulitis?
Pneumococcus
S. aureus and group a strep from minor trauma
What should be done with occult bacteremia secondary to H. influenza?
results in 30-50% developing meningitis or other deep focal infection. Must treat with antibiotics.
What is the antibiotic of choice for invasive hib infection vs. non-invasive infection
Invasive: 3rd generation cephalosporin: ceftriaxone, cefotaxime
Non-invasive: amoxicillin or augmentin if not responding
Who gets chemoprophylaxis if they have been exposed to invasive Hib? What antibiotic is used?
Rifampin to household contacts and daycare attendees
to all household members if one person is immunocompromised or < 4 years of age and incompletely immunized
daycare if they have had two cases in the last 60 days
What is the gram stain for Yersinia pestis. What disease does it cause? How is it transmitted?
gram negative coccobacillus
plague, large lymphadenopathy that supinates, (bubonic) and can result in sepsis
fleas, rodents or direct contact with skinning animals
Diagnosis and treatment for Yersinia pestis?
culture, serology. Occurs more frequently in desert south west.
gentamycin, streptomycin
Gram stain for Yersinia enterocolitica and what disease dose it cause?
gram negative coccobacillus
makes endotoxin and enterotoxin, people get sick after eating contaminated food, especially pork (chitterlings) causes a GI disease
Older children can get a pseudoappendicitis syndrome where they clinically present like they have appendicitis
Who is at risk for bacteremia from Yersinia enterocolitica and what is the treatment
very young, those with iron overload
treat those with bacteremia and immunocompromised with TMP/SMX, aminoglycosides
What is the gram stain for Legionella pneumophila and what sort of illness does it cause?
gram negative bacilli, found in water and transmitted via aspiration
legions of problems:
diarrhea, CNS symtpoms, renal disease plus pneumonia
How do you treat legionella?
Azithromycin or quinolones
How is brucellosis transmitted, and what symptoms does it cause?
zoonosis transmitted to humans via unpasteurized milk, inhalation or handling carcasses.
Affects heart- culture negative endocarditis, lungs, GU tract (orchitis, abortion), endocrine (thyroiditis, adrenal insufficiency), sacroiliitis, granulomatous hepatitis.
When should you check for brucellosis and how do you treat it?
Fever of unknown origin. Culture is difficult and takes a long time.
Doxycycline for 6 weeks and aminoglycoside for 2 weeks or
doxycycline and rifampin for 6 weeks,
if less than 8 years old TMP/SMX and rifampin
Gram stain for Francisella tularensis, how is the disease transmitted, and what are the symptoms?
gram negative pleomorphic bacillus
tularemia
prevalent in Arkansas, Missouri and Oklahoma
ticks, blood sucking flies or can be ingested (rabbits)
fever, chills, myalgias and arthralgias with an irregular ulcer at site of inoculation with lymphadenopathy that may suppurate
How do you diagnose and treat tularemia
clinical syndrome confirmed with serologic testing
gentamicin or stretomycin
How does bartonella present?
> 3 weeks of chronic, tender, regional lymphadenopathy with history of cat exposure
Enlarged node with resolve in 4-6 weeks but 25% will suppurate.
Describe an atypical presentation of bartonella
Parinaud’s: patient is inoculated near the eye and gets conjunctivitis and ipsilateral periauricular lymphadenitis.
other form: hepatosplenic granulomas, FUO, aseptic meningitis, encephalopathy
How do you treat bartonella?
Can use PCR and serum antibodies to diagnose
Do not incise and drain-will cause persistent sinus tract
If biopsied will show necrotizing granulomas
symptom relief as it will resolve in 2-4 months, may aspirate lymph node for symptom relief
may treat with azithromycin early on or if severely ill
How to treat pasturella. What has usually happened to the patient to be infected?
cat bite, usually deep puncture wound
isolated infection: penicillin
however, usually concern for mixed flora so often Augmentin is used
if penicillin allergic: TMP/SMX and clindamycin
How does campylobacter present?
fever with diarrhea / gastroenteritis, stool can be bloody
febrile seizures, can mimic appendicitis ir intussusception
can cause guillain-barre syndrome
How is campylobacter treated
azithromycin, erythromycin
What test do you get if exam mentions a neonate with citrobacter growing in blood or CSF.
CT/MRI to look for brain abscess
What is the gram stain for Rickettsia rickettsia and what disease does it cause, with its symptoms
gram negative coccobacillus
Rocky Mountain Spotted Fever
fever, headache, arthralgias, diarrhea, abdominal pain
rash-distal extremities progresses from macular popular to petechial to purpura
hyponatremia and thrombocytopenia are helpful clues
history of tick bite in the south east plus Missouri and arkansas
How is q fever, coxiella burnetti, transmitted and how do you diagnose?
zoonosis transmitted to humans via inhalation of aerosol from infected animal, usually in slaughterhouses or products of conception from birthing an animal. (cattle, cats or conception =coxiella)
serology or staining biopsy tissue
How do you treat rickettsial infections. (includes q fever)
doxycycline even for those < 8 years of age
Describe symptoms, lab findings and treatment of Ehrlichia /Anaplasma
Rocky Mountain spotless fever
small gram negative intracellular organisms
human monocytic ehrliciosis and human granulocytic anaplasmosis.
HME: texas, Oklahoma, Missouri and Arkansas
HGA: northeast and Midwest
can have a rash with fever, viral syndrome and leukopenia, thrombocytopenia
think tick bite and pancytopenia
usually isolate in culture, PCR or seen in WBCs
treat: doxycycline
How does fusobacterium present?
anaerobe causes Lemierre disease that causes internal jugular vein thrombophlebitis or thrombosis with signs of septic lung emboli.
Fever, sore throat that progresses to severe neck pain and unilateral neck swelling, trismus and dysphagia
Treat with metronidazole
Describe usual TB symptoms in an infant
non-productive cough, wheezing especially at night.
CXR with hilar lymphadenopathy
lymph nodes can compress bronchial structures causes air trapping- emphysema
Describe the pleural effusion that can be seen in children with TB.
Many have an asymptomatic pleural effusion
lymphocyte count 1000-6000, low glucose, high protein, elevated LDH, usually smear will be negative
Describe TB meningitis findings in children
usually 6 months to 4 years
caseous cession in the cerebral cortex or meninges which seeds the subarachnoid space. can cause a communicating hydrocephalous, SIADH
CSF protein is elevated, glucose is low with CSF WBC count elevated with lymphocyte predominance
What is the most common extra pulmonary manifestation in TB
lymph node involvement
anterior and posterior cervical triangle, submandibular and supraclavicular lymph nodes
Common symptoms of TB in adolescents
fever, weakness, night sweats and weight loss
cough, pleuritic chest pain, hemoptysis
upper lobe infiltrate and hilar lymphadenopathy
Who gets screened for latent TB infection?
HIV or high risk for HIV
close contacts of those with TB
IV drug users
homeless
migrant workers
residents in long term care facilities
patients who are about to start immunosuppressive therapy
children traveling to or immigrating from endemic countries
children with symptoms suggestive of disease
How do you screen for TB?
TST: preferred for those < 5
IGRA: preferred in children who have had the BCG vaccine and are > 5 years old or children who are unlikely to return in 48-72 hours
What are some caveats to TST testing
10% of children are initially anergic and actually have TB, it also takes 10-12 weeks for positive test after exposure.
so if skin test is negative in someone recent exposed, treat and recheck in 10-12 weeks
TST is only contraindicated when there has been a necrotic skin reaction to previous tests
For who is a 5 mm TST test considered positive
Those at high risk:
CXR finding or those with symptoms consistent with disease
HIV or major cell mediated dysfunction
fibrotic changes on CXR consistent with prior TB
close contacts of a documented case
immunosuppressed patients, > 15 mg of pred daily
For whom is a 10 mm TST considered positive
moderate risk: homeless healthcare workers recent travel or birth in an endemic area IV drug users prisoners nursing home patients and staff diabetics, chronic renal failure children < 4 immunosuppressant therapy < 15 mg of pred daily
