DR. REEMA KUMARI

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• DR. REEMA KUMARI
• Associate professor
• Department of community medicine and public health

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• The earliest clear account of whooping cough was
  described in 1640 by Baillow, an epidemiologist
• The name pertussis means violent cough, and
  was first used to describe the disease in 1679.
• In China, the disease is known as Hundred Day
  Cough

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• An acute infectious disease, usually of young
  children caused by B.pertussis.
• Insidious onset with mild fever and an irritating
  cough gradually becoming paroxyamal with the
  characteristic whoop

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• Pertussis toxin and filamentous hemagglutinin
  (FHA) allow binding of pertussis to repsiratory
  epithelial cells.
• PT can then enter the bloodstream.

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• Pertussis is a disease of worldwide importance,
  with an estimated 285,000 deaths in 2001, with
  most occurring in Africa and SE Asia
• According to the WHO,2010 there are 1.29 lac
  cases reported globally, with 95 occurring in
  developing countries,and the DPT(3) Immunisation
  rate was 85.
• In India yr.1987 incidence was 1.63 lac cases,in
  2011only 39,091 cases were reported (decline of
  76)

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• AGENT FACTORS
• B pertussis is very contagious, and attack rates
  among susceptible groups range from 50-100
  depending on the nature of the exposure.
• B.pertusis occurs in smooth and rough phases,
  capsulated and non-capsulated form,elaborates an
  exotoxins and endotoxins
• B.pertusis is antigenically highly complex.it
  carries 3 major agglutinogens-1,2,3 and several
  minor ones
• Survives only for very short periods outside the
  human body

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• AGE disease of infants and pre-school children
  however, children under the age of 5 years are at
  the highest risk of developing more serious
  symptoms.
• Being in close contact with an infected person
  for extended periods of time increases the risk
  of becoming infected
• IMMUNITY recovery from whooping cough or
  adequate immunisation is followed by
  immunity.infants are susceptible to infection
  from birth bec. Maternal antibody does not appear
  to give them protection. no cross immunity with
  B. Parapertussis

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• B. pertusis infects only man, source is a case of
  pertusis
• Transmission is felt to occur by aerosol droplet,
  and exposure to a coughing patient.
• There are no known animal reservoirs for B
  pertussis, and the organism does not survive for
  prolonged periods in the environment.
• No long-term carrier state had been identified,
  but asymptomatic culture positive persons can be
  detected during known exposures.

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• The bacilli occurs abundantly in the
  nasopharyngeal and bronchial secretions, which
  are infective
• Objects freshly contaminated by such discharges
  are also infective

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• Whooping cough is most infectious during
  catarrhal stage.
• The infective period may be considered to extend
  from a week after exposure to about 3 weeks after
  the onset of paroxysmal stage

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• Whole cell pertussis vaccine has been responsible
  for a major reduction in disease incidence, but
  has caused a shift in the peak age of disease.

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• Stage 1 (Catarrhal)
• Cold, runny nose and irritating cough
• Most infectious stage
• Stage 2 (Paroxysmal)
• Severe series of coughs usually ending with a
  high-pitched whoop
• The whoop starts 1 to 2 weeks after the cold
  symptoms and lasts 1 to 2 months
• Thick, clear, sticky mucous may be coughed up
  at the end of the coughing spasm
• Coughing spasms are more frequent at night

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• Stage 3 (Convalescent)
• Gradual disappearance of symptoms occurring
  over 2 to 4 weeks, however, coughing spells can
  last for weeks or months
• Cough may become louder and may sound like it
  is getting worse as the person is getting better
• Coughing may flare up again later in a cold or
  upper respiratory illness. This does not mean
  that the person has been re-infected with
  pertussis

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• After an incubation period of 1-3 weeks, signs
  and symptoms of the catarrhal phase begin
• Symptoms include rhinorrhea, lacrimation,
  conjunctival injection, malaise, low grade fever,
  and are indistinguishable from those of many
  other URIs.
• After a few days and up to a week of these
  symptoms, a dry nonproductive cough develops, and
  this evolves into a characteristic paroxysmal
  phase.

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• Patients are most contagious during the catarrhal
  phase and during the first two weeks after the
  onset of coughing.
• Prodromal symptoms during this phase can include
  complaints of pharyngeal discomfort.
• During this phase, patients can develop a marked
  leukocytosis, with WBC counts greater than
  50,000, with a relative lymphocytosis (less
  common in adults).

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• The cough paroxysm consists of a short series of
  expiratory bursts, followed by an inspiratory
  gasp, which results in the typical whoop.
• The paroxysmal phase usually lasts 1-6 weeks, but
  can last up to 10 weeks
• Not all children with pertussis exhibit the
  characteristic whoop, and it is fairly uncommon
  in infants, who may have apneic episodes

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Child having Loud crowing inspiration
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• In adults, whooping is variable, ranging from
  20-40 in various studies. The disease is
  generally milder, but the paroxysmal cough may be
  just as prolonged.
• Paroxysms can number more than 30 per 24 hours,
  and are more frequent at night, and can be
  stimulated by external stimuli, such as noises or
  cold air.

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• Classically they may end with a vomiting episode.
  They can be associated with sweating, flushing
  and syncope. Patients may cough up thick yellow
  plugs.
• Pertussis is generally more severe in infants,
  but presentation can be more atypical in infants,
  as well as partially immunized children and
  previously immunized adolescents and adults.
• In these groups the catarrhal phase can be
  shortened, and the true whooping phase may be
  absent.

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• The convalescent phase begins with a decrease in
  the intensity of the cough and paroxysms, but can
  still last for weeks.
• It is not clear if pertussis can cause long term
  impairment of pulmonary function.

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• Complications occurs in 5-6 percent of cases
• The chief complications of pertussis are
  bronchitis, bronchopneumonia and bronchiactasis
• secondary infections- otitis media or pneumonia
  (either secondary to pertussis or other
  organisms)
• Aspiration can occur secondary to the whooping
  and associated gasping

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• Patients can develop subconjunctival hemorrhages,
  epistaxis,haemoptysis and punctate cerebral
  haemorrhages which may cause convulsions and coma
• CNS abnormalities can occur particularly in
  children 6 months and younger.

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• Direct fluorescent antibody tests (DFA) are often
  used as well, but they can be less sensitive and
  less specific, and may lead to overdiagnosis and
  overtreatment (higher false positives from cross
  reaction with normal naso-pharyngeal flora).
• With new PCR technology becoming available, the
  ability to diagnose Bordetella infection has been
  greatly enhanced

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• A clinical case is defined as a cough illness
  lasting at least 2 weeks without other apparent
  cause accompanied by one of the following
• Paroxysms of coughing
• Inspiratory whoop
• Posttussive vomiting

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• The newer macrolides (azithromycin and
  clarithromycin) have good in vitro acitivty
  against B pertussis, and Clarithromycin (500 mg
  bid) used for 10 14 days and Azithromycin (500
  mg/d) used for 5 7 days have been used with
  good results.

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• Steroids may reduce the number and severity of
  cough paroxysms, but are generally only
  recommended for infants with serious disease.

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• Antibiotics can be used for 2 purposes in the
  control and prevention of pertussis
• 1) Treatment to modify clinical symptoms of
  pertussis by administering to symptomatic
  patients

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• 2) Prevention of secondary spread of pertussis by
  administering to
• a) Symptomatic patients (treatment) and
  interrupting infectiousness and transmission by
  eliminating the organism from the respiratory
  system.
• b) Asymptomatic contacts (prophylaxis) and
  interrupting transmission by eliminating any
  organisms that may have been contracted

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• Other methods of preventing the spread of
  Pertussis include
• Washing hands with soap and warm water.
• Teaching children to cover mouth and nose if
  coughing or sneezing and to wash hands after
  doing so.
• Not sharing eating utensils and drinking
  glasses.
• Minimizing the amount of contact you have with
  someone you know is infected or if you are
  infected, minimizing the amount of time you are
  around others.

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THANK YOU