Pertussis and RSV (quiz 2, exam 1) Flashcards
Bordetella pertussis is also known as
whooping cough; in China its “the cough of 100 days”
Pertussis is a highly contagious, acute __ illness caused by __
- respiratory
- gram negative coccobacillus, B. pertussis
Pertussis is strictly a __ pathogen
human (no known animal reservoir)
pertussis pre-vaccine ear is mainly affected for children __ years old
<10 years
pertussis is manifested as a prolonged __ illness with respiratory __, __ cough, and __ emesis
- cough
- whoop (upon inspiration)
- paroxysmal
- post-tussive
pertussis diagnostic highlights: predominantly in infants under the age of
2
pertussis diagnostic highlights: adolescents and adults are an important __ of infection
reservoir
pertussis diagnostic highlights: __ week prodromal catarrhal stage of __, __, __, and __
- 2wk
- malaise
- cough
- coryza
- anorexia
pertussis diagnostic highlights: absolute__, often striking (rarely in adults)
lymphocytosis
pertussis diagnostic highlights: __ confirms the diagnosis
culture
pertussis epidemiology: epidemiology has changed since intro of vaccine, since 1990s, more than half of cases have been in __
adolescents and adults
pertussis epidemiology: infected adolescents and adults serve as a __ for infection of infants and children who have higher __ and __
- reservoir
- morbidity
- mortality
pertussis epidemiology: incubation period is _-
7-10 days (can be > or = to 3 weeks)
pertussis epidemiology: spread via
respiratory droplets (by paroxyms of coughing)
pertussis epidemiology: pts with prior infenction or vaccine induced immunity may or may not have
classic symptoms
pertussis epidemiology: spread of infection unlikely without __ and pts are infectious until they have completed __ days of appropriate antibiotics
- cough
- 5 days
pertussis epidemiology: most people have waxing immunity after __ years
5-10 years (rarely lasts more than 12 years)
pertussis epidemiology: groups at highest risk are
- infants 65 yo more likely to be hospitalized
- obesity
- asthma
pertussis epidemiology: most infants acquire the infection from
adolescents and adults in their own household
pertussis epidemiology: booster vaccination is recommended for
adolescents (~10-11 years old) and adults
pertussis: between __ and __% of pts with cough persisting greater than 1 week post-URTI have pertussis
7-32% (common cause of acute cough among adults)
pertussis: adults with Bordetella pertussis infection may be asymptomatic, or present with these types of sypmptoms
non specific symptoms indistinguishable from URI
pertussis pathogenesis: transmitted by __ and adheres to __
- aerosolized droplets
- ciliated upper respiratory tract epithelial cells (the damage caused to ciliated epithelial cells has to heal for the cough to go away)
pertussis clinical manifestations: infection is characterized by these 3 phases __, __, and __, and the total duration of all 3 phases is often about __ months
- Catarrhal phase
- Paroxysmal phase
- Convalescent phase
- 3 months
pertussis: catarrhal phase lasts __
1-2 weeks
pertussis: signs and symptoms in the catarrhal phase
- non specific generalized symptoms that resembles the common cold
- malaise
- rhinorrhea
- mild cough
- possible low grade temps
- excessive lacrimation (potentially)
- conjunctival injection (potentially)
pertussis: the most contagious phase is the
catarrhal phase
pertussis: the paroxysmal phase begins in the __ week of illness and can last __ weeks
- 2nd week
- 2-6 weeks
pertussis: signs and symptoms in the paroxysmal phase
- paroxysmal cough (hallmark symptom): series of severe, vigorous coughs during a single expiration (fits of cough)
- vigorous inspiration causes the distinctive “whooping” sound (not always present, esp. adults and adolescents)
- cyanosis, apnea, bradycardia, post-tussive syncope or emesis can occur in infants and young children
pertussis: complications more likely during what phase
paroxysmal phase
pertussis: whooping sound in infants and small children due to
small caliber trachea
pertussis: paroxysmal phase coughing can be triggered when pt __(4) or by __(2), can be worse at __, and pts may often feel __ between cough paroxysms
- yawns, laughs, yells, or exercises
- steam inhalation, mist
- night
- well between coughs and have few symptoms
pertussis: in the convalescent phase, there is a gradual reduction in the
frequency and severity of the cough
pertussis: the convalescent phase usually lasts __ weeks but may be prolonged
1-2 weeks
pertussis: during the convalescent phase, episodic coughing may reappear with subsequent __ during this phase
URIs
pertussis: atypical presentations in infants
- catarrhal stage is short or absent
- early symptoms include feeding difficulties, tachypnea, cough
- paroxysms of cough may be only sign of illness, with infant appearing deceptively well between episodes
- many do not have the whoop
- history of someone in household having a cough
pertussis: atypical presentations in vaccinated children
- clinical presentation and course is usually less severe than in unvaccinated children
- shorter duration of cough than in unvaccinated
- decreased incidence of apnea and cyanosis
pertussis: atypical presentations in older children, adolescents, and adults
- less severity and symptoms
- prolonged cough may be only symptom
- typically not the whoop
- may have sputum production, coryza, sweating episodes, sore throat
pertussis: complications in young infants
- APNEA (<6 mos old)
- PNEUMONIA
- FEEDING DIFFICULTIES W/ SUBSEQUENT WEIGHT LOSS (FTT)
- POST-TUSSIVE VOMITING
- seizures/death
- difficulty sleeping
- pneumothorax
- epistaxis
- subconjuntival hemorrhage
- subdural hemorrhage
- rectal prolapse
- urinary incontinence
- rib fracture (pressure related)
pertussis: complications in adolescents and adults
- pneumonia (due to infection itself)
- otitis media (due to infection itself)
- subconjuntival hemorrhage
- hernia
- rib fracture
- urinary incontinence (due to mechanical sequelae of severe cough)
pertussis: is a __ diagnosis
clinical diagnosis (based on history and physical)
pertussis, diagnosis: clinical suspicion usually arises only when
severe coughing persists after resolution of URI symptoms
pertussis, diagnosis: early diagnosis is important to __, and antibiotics may __
- decrease spread of infection
- shorten the duration of symptoms (if caught early)
pertussis, diagnosis: consider diagnosis in all children, regardless of vaccination status, who present with cough for __ days
14 or more days
pertussis, diagnosis: diagnostic testing is important for these 2 reasons
- to confirm an uncertain diagnosis
2. public health considerations
pertussis: 3 groups of people you should concerned when they present with cough
- pregnant women (esp. if in 3rd trimester)
- healthcare worker
- someone who works with kids
pertussis: a clinical case is defined as a person
who has a cough illness lasting at least 2 weeks with one of the following: paroxysms of coughing, inspiratory “whoop”, or post-tussive vomiting, and without other apparent cause (as reported by a health professional)
pertussis: the laboratory criteria for diagnosis are
- the isolation of B. pertussis from a clinical specimen OR
2. positive polymerase chain (PCR) reaction assay for B. pertussis
pertussis: a confirmed case is defined as a person
- with an acute cough illness of any duration who is culture pos. form nasopharyngeal secretions
- who meets the clinical case def. with lab confirmation by PCR from nasopharyngeal secretions
- who meets the clinical case def. and is epidemiologically linked directly to a case confirmed by either culture or PCR from nasopharyngeal secretions
pertussis: a probable case is defined as a person
who meets the clinical case definition without lab confirmation or an epidemiologic link to a lab confirmed case
pertussis, diagnosis: the appropriate diagnostic evaluation includes __ and __; __ may yield the diagnosis if performed early in the disease course; __ is the current diagnostic standard
- serology
- PCR
- culture of a throat swab
- PCR
pertussis, timeline for diagnosis: weeks of cough onset when culture, PCR, and serology should be done
- culture: 0-2 weeks
- PCR: 0-3 weeks (and 3-4 weeks)
serology: 2-8 weeks (and 8-12 weeks)
pertussis: specimens must be collected by swab or aspiration from __
ciliated respiratory epithelium of the posterior nasopharynx where B. pertussis resides
pertussis: suspect pertussis in
- infants and children w/ paroxysmal cough (kids present earlier)
- infants and children w/ severe cough for more than 5-7 days
- infants and children who develop apnea, cyanosis, or gagging cough
- infants with persistent cough, post-tussive emesis
- lab confirmation recommended
pertussis: first line treatment
macrolides: erythromycin, azithromycin, clarithromycin (side effects include GI upset)
pertussis: alternative treatment
TMP-SMZ DS
pertussis: Abx during catarrhal phase effects
decrease severity and duration of cough
pertussis: Abx later in the course of disease effects
wont effect course of symptoms but will decrease spread of disease (wait until 5 days of treatment)
pertussis: T or F, there is proven effective treatment for pertussis cough
false
pertussis: treatment of infants and children should include
- supportive care (may include hospitalization for monitoring of respiratory status, fluid and nutritional support)
- avoidance of triggers for coughing paroxysms
pertussis, treatment of infants and children: indications for hospitalizations include
- respiratory distress
- pneumonia
- inability to feed
- cyanosis
- apnea
- seizures
- hospitalization for infants < 3mos old usually required (clinical decomposition can be rapid)
pertussis: prevention
- erythromycin (macrolide) prophylaxis to household, day care worker, healthcare worker, high risk close contact
- vaccine (DTaP = diptheria, tetanus and pertussis) for children
- vaccine booster (Tdap = tetanus, lower diptheria antigens, and lower pertussis antigens) for adolescents and adults (Boostrix and ADACEL)
RSV (respiratory syncytial virus), epidemiology: it is this type of virus
paramyxovirus
RSV (respiratory syncytial virus), epidemiology: causes __ in persons of all ages
acute respiratory tract illnesses
RSV (respiratory syncytial virus), epidemiology: seasonal outbreaks
Nov. - Apr. (with peaks in Jan. or Feb.)
RSV (respiratory syncytial virus), epidemiology: most common cause of __ in children less than 1 yo
LRTI
- bronchiolitis (60-90%)
- pneumonia (25%)
RSV (respiratory syncytial virus), epidemiology: it is a major cause of __ infections
nosocomial
RSV: most children infect by age __ and __ are common
- 2
- reinfections
RSV: dominant strains __ yearly; subtypes include __
- shift
- A (causes more severe disease) and B
RSV: spread mainly by
direct contact but also aerosol droplets
RSV: ca remain alive on hands and surface up to __
4 hours
RSV: viral shedding usually __, but can be up to __ in young infants
- 3-8 days
- 4 weeks
RSV: incubation period is
2-8 days
RSV: risk factors of RSV related LRTI include
- infants <6mos old (esp. if born during first half of RSV season)
- day care
- infants and children w/ underlying pulmonary disease, cardiovascular or neuromuscular disease
- premature infants
- infants exposed to second hand smoke exposure
- immunocompromised
- severe asthmatics
RSV, clinical manifestations in older children and adults usually with URI
- rhinorrhea
- cough
- coryza
- conjunctivitis
- sinusitis
- OM
RSV, clinical manifestations in infants and young children with primary infection usually present with LRTI
- cough
- fever
- wheezing (due to infection resulting in inflammation of bronchioles)
- tachypnea
- thick nasal congestion
- labored respirations (as evidenced by grunting, nasal flaring, intercostal retractions)
- apnea
- hypoxia
RSV: increased incidence of __ later in life
reactive airway disease (like asthma): unclear whether viral respiratory infection causes asthma or if wheezing with these infections is a predictor of childhood asthma
RSV: DDx
- parainfluenza virus
- adenovirus
- influenza virus
- rhinovirus
- coronavirus
- human bocavirus
RSV: DDx in infants, elderly, and immunocompromised
- metapneumovirus in infants
- influenza in elderly
- parainfluenza in immunocompromised
RSV, diagnosis: __ diagnosis and __ not routinely recommended
- clinical diagnosis
- labs
RSV, diagnosis: diagnostic tests
- rapid antigen tests (90% sensitivity and specificity for most)
- PCR (alternative to culture for confirming rapid antigen test)
- simulfuor respiratory screen for influenza A and B, parainfluenza, adenovirus, RSV (uses DFA with results in a few horus and costs about $30)
- in adults, almost universal presence of sinusitis on radiological studies (xray)
RSV: treatment
- maintenance of oxygenation and hydration
- albuterol nebulizer commonly used for wheezing in bronchiolitis if clinical response
- ribavirin has been used in hospitalized immunosuppressed pts with severe RSV
- syngais (palivizumab) used to prevent RSV in preemies (ab = antibodies)
RSV: children with these symptoms usually require hospitalization for supportive are and monitoring
(moderate to sever respiratory distress)
- > 70 bpm
- dyspnea
- cyanosis
- nasal flaring
- retractions
- grunting
- poor feeding
- lethargy
- apnea
- hypoxemia (check pulse ox)
RSV: prognosis
- most children recover unenventfully and do not have further wheezing episodes
- up to 40% with bronchiolitis develop further wheezing episodes up to 5 yo and 10% beyond that
- mortality in hospitalized pts is < 2%
