Pertussis Whooping cough is back

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PertussisWhooping cough is back

• Adapted for BugLine from presentation by
• Cassandra D. Youmans, MD, MPH, MS-HCM, FAAP
• District Health Director
• East Central Health District VI

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Objectives

• Enhance East Central Public Health District VIs
  ability to recognize and respond appropriately to
  pertussis
• Refresh University Hospital healthcare personnel
  to allow appropriate treatment and reporting of
  pertussis
• Give Tdap vaccine to healthcare personnel to
  protect our
• Highest risk patients by surrounding them
  immunity
• A circle of immunity made up of vaccinated
  caregivers
• Healthcare personnel from catching pertussis
• Tdap, Tetanus, diphtheria and pertussis

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Two Pupils Treated for Pertussis Saturday, April
15, 2006

• Columbia County School officials confirmed that
  at least one pupil tested positive for whooping
  cough, and the two siblings are being treated.
  One attended Evans High School, and the other
  Evans Middle Schoolhighly contagious, spread
  through the air by cough and begins with cold
  symptoms and a cough
• The case was not properly reported to the public
  health department, allowing for the above
• And the article included a warning to parents

Augusta Chronicle
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Resurgence of Pertussis

• Mutation
• Waning vaccine-induced immunity 5 to 7 years
  after vaccination, leaving adolescents and adults
  unprotected
• Waning disease-induced immunity doesnt last much
  longer than that of vaccination
• Enhanced identification Public health awareness,
  surveillance, diagnostic programs

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Bordetella pertussis, the germ

• Gram-negative rod
• Humans are the only host
• Incubation period 6-to-21 days (usually 7-to-10
  days)
• Duration of illness 6-to-10 weeks (usually 6
  weeks)
• Expected occurrence 3-to-5 year cycles of
  increased disease
• Pertussis is under reported, 40-160 fold less
  than actual illness
• Asymptomatic infections are 422 times more
  common than symptomatic infections

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Spread

• Close person to person contact via aerosolized
  droplets from respiratory secretions of patients
  with disease
• 90 of nonimmune household contacts acquire the
  disease
• Adolescents and adults (27 of reported cases in
  2004) are the major source of infection in
  unvaccinated children
• Infants and young children are infected by older
  siblings who have mild to asymptomatic disease
  (43 of reported cases)

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Clinical Symptoms

• Initially mild upper respiratory tract symptoms
  (catarrhal stage,1-2wks), most contagious period
  progressive paroxysms of cough (paroxysmal stage
  2-4 wks)
• Inspiratory whoop, followed by vomiting
• Fever minimal to absent
• Symptoms subside gradually over months
  (convalescent stage1-2 wks)

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Clinical Symptoms in Infants

• Most severe in infants lt6 months
• Atypical presentation
• Apnea most common symptom
• Whoop is absent
• Hospitalization often needed
• Lymphocyte predominant, increased white count can
  match severity of the cough

• Infant Complications
• Seizures (3)
• Pneumonia (22)
• Encephalopathy (1)
• Death
• Case fatality rate
• 1.3 in infants lt1 month
• 0.3 in infants 2-11 months

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Diagnosis

• Increase of pertussis antibody
• IgA antibody titer to pertussis is becoming the
  method of choice
• IgG antibody to pertussis toxin indicative of
  recent infection
• Single serum test for significantly high
  pertussis specific antibody can confirm the
  diagnosis
• Adolescents and adults with B. pertussis cough
  illness dont seek care until the week 3-4 of
  illness
• Organism most frequently recovered in catarrhal
  or early paroxysmal stage
• PCR on nasopharyngeal secretions obtained with
  Dacron swab, put on special media, with 10 to 14
  day incubation
• Alert the Lab when pertussis is suspected - the
  culture media is not readily available
• Negative cultures are common

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Treatment

• Aim is to eradicate nasopharyngeal carriage
• Treatment duration usually 14 days with
  erythromycin sulfate (EES), newer Macrolides 5-7
  days
• Macrolides-erythromycin, azithromycin, and
  clarithromycin
• Azithromycin eradicates naso-pharyngeal carriage
  the fastest
• Hypertrophic pyloric stenosis has been reported
  with oral EES in infants younger than 6 weeks
• Trimethoprim-sulfamethoxazole is an alternative
  to erythromycin-resistant strain, or for
  intolerance to macrolides
• Penicillins, first and second generation
  cephalosporins are not effective

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Supportive Care

• Hospitalized patients need to be on Droplet
  Isolation for 5 days after therapy
• Monitor exposed children for respiratory symptoms
  for 20 days
• Laboratory confirmation is difficult, so
  diagnosis often based on characteristic clinical
  manifestations
• Children may return to school after 5 days of
  appropriate antibiotic therapy

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Prevention - Terms

• Tetanus Diphtheria (Td)
• Tetanus Toxoid, Reduced Diphtheria Toxoid and
  Acellular Pertussis Vaccine, Adsorbed (Tdap)

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Prevention Immunization

• Universal immunization of all children lt7 years
  of age is recommended by the AAP
• U.S. pertussis is an acellular vaccine in
  combination with diphtheria and tetanus toxoids
• Acellular vaccines contain one or more immunogens
  from B pertussis
• Acellular vaccines are absorbed on aluminum salt
  and must be given intramuscularly
• 3 DTaP, and 1 combined vaccine that includes DTaP
  and Haemophilus influenzae type b conjugate
  vaccine is given at 15-18 months

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Recommendations of the Advisory Committee on
Adult Immunization Practices (ACIP)

• One dose of Tdap for adults 19 64 years of age
  to replace the next booster does of tetanus and
  diphtheria toxoids vaccine (Td)
• Tdap for adults who have close contact with
  infants lt12 months of age
• May give Tdap within 2 year intervals to protect
  against pertussis
• Tdap is not licensed for adults gt65 years

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Contraindications and Precautions

• Contraindications to Tdap
• History of serious allergic reaction
• (anaphylaxis) to vaccine components
• History of encephalopathy not attributable
• to an identifiable cause within 7 days of
  vaccination
• with pertussis vaccine
• Precautions to Tdap
• Guillain-Barre Syndrome, 6 weeks
• after a dose of tetanus toxoid
• Moderate to severe acute illness
• Unstable neurological condition

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References

• ACIP Votes to Recommend Use of Combined Tetanus
  Diphtheria and Pertussis (Tdap) Vaccine for
  Adults. Advisory Committee on Immunization
  Practices. 2006
• Cherry, JD. MD, MSc. The epidemiology of
  pertussis, Pediatric Infectious Disease Journal.
  2006 254361-362
• Pickering, LK. Pertussis.The Red Book. 2003
  26472-486
• Gilbert, D.N. The Sanford Guide to Antimicrobial
  Therapy. 2005 3524

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Questions?