The incubation period varies from 7 to 14 days. It is a disease of childhood with 90% of cases occurring below 5 years of age. 

The disease manifests in 3 stages: first is the catarrhal stage, followed by the paroxysmal stage and lastly, the convalescent stage. During the catarrhal stage, patients are highly infectious and their cultures from respiratory secretions are positive in most of the cases.

Malaise, anorexia, coryza, mild cough, mucoid rhinorrhoea and conjunctivitis are present. Paroxysms of cough begin about a week later. Paraoxysms with the classic inspiratory whoop are seen mainly in younger children in whom the lumen of the respiratory tract is compromised by mucosal secretion and mucosal oedema. The whoop results from air being forcefully drawn through the narrowed tract.

The disease runs an atypical course in partially immunised older children and in adults in whom cough is persistent and prolonged often without a whoop which makes diagnosis difficult for them.

Paraoxysms usually end in vomiting. Paraoxysmal stage lasts for about 2-6 weeks. Diminishing intensity and frequency of cough indicate the onset of the convalescent stage which may continue for 1-2 weeks.

Infants and young children are more sensitive to complications. Respiratory complications include otitis media, pneumonia either due to Bordetella pertussis or bacterial pneumonia.

At the peak of the disease, seizures and encephalopathy may occur. Malnutrition is often the end result in infancy and early childhood.

• Fever

  If your child develops a fever, you can give them a medication containing acetaminophen. [bccdc.ca]

  Both paroxysmal cough and absence of fever had high sensitivity (93.2% [95% CI, 83.2-97.4] and 81.8% [95% CI, 72.2-88.7], respectively) and low specificity (20.6% [95% CI, 14.7-28.1] and 18.8% [95% CI, 8.1-37.9]). [ncbi.nlm.nih.gov]

  Tick-borne Rickettsia rickettsii Rocky Mountain spotted fever Rickettsia conorii Boutonneuse fever Rickettsia japonica Japanese spotted fever Rickettsia sibirica North Asian tick typhus Rickettsia australis Queensland tick typhus Rickettsia honei Flinders [en.wikipedia.org]

  […] symptom of B. pertussis whooping cough disease is uncontrollable coughing. 2 Symptoms of B. pertussis at its onset are similar to the common cold, or an allergy attack with stuffy or runny nose, dry cough, loss of appetite, fatigue and, sometimes, a low fever [nvic.org]

  Fever, if present, is usually mild. Symptoms appear between six to twemty-one days (average 7-10) after exposure to the pertussis bacteria. [health.mo.gov]

• Swelling

  This can be hives, wheezy breathing, or swelling of some part of the body. If this happens, particularly swelling around the throat, immediately get to your family doctor or hospital emergency. [bccdc.ca]

  Swelling involving the entire thigh or upper arm has been reported after booster doses of certain acellular pertussis vaccines. The limb swelling may be accompanied by erythema, pain and fever. [web.archive.org]

• Pain

  Hives Pale skin Fast heartbeat Dizziness Over-the-counter pain relievers such as acetaminophen or ibuprofen can help ease pain and reduce fever. [walgreens.com]

  A previously healthy 27-year-old Hispanic man presented to an emergency department with headache, periorbital pressure, pain with ocular movements, and intermittent blurred vision that developed 1 day after administration of the diphtheria, tetanus, pertussis [ncbi.nlm.nih.gov]

  Antipyretic/analgesic medication might also be used in a 'reactive' fashion after a low fever or mild pain had occurred, in order to prevent a higher fever or more severe pain. [doi.org]

• Malaise

  The initial catarrhal stage presents with nonspecific symptoms of malaise, rhinorrhea, sneezing, lacrimation, and mild cough. [aafp.org]

  The first stage, colonization, is an upper respiratory disease with fever, malaise and coughing, which increases in intensity over about a 10-day period. [textbookofbacteriology.net]

  Malaise, anorexia, coryza, mild cough, mucoid rhinorrhoea and conjunctivitis are present. Paroxysms of cough begin about a week later. [symptoma.com]

  6 to 10 weeks, progressing through three stages: Mild coldlike symptoms Severe coughing fits Gradual recovery Coldlike symptoms include sneezing, runny nose, loss of appetite, listlessness, a hacking cough at night, and a general feeling of illness (malaise [msdmanuals.com]

• Fatigue

  Early symptoms are those of a cold: runny nose, low/no fever, mild cough After 1-2 weeks: vomiting, breathing problems, extreme fatigue, whooping sound For babies: gasping or gaging, breathing may stop, seizures Good to know… Pertussis is cyclical, with [acphd.org]

  […] in the body. 1 The major symptom of B. pertussis whooping cough disease is uncontrollable coughing. 2 Symptoms of B. pertussis at its onset are similar to the common cold, or an allergy attack with stuffy or runny nose, dry cough, loss of appetite, fatigue [nvic.org]

  A severe infection may require hospitalization, and recovery can take months; the illness can have a lasting effect on lung function, leaving people with shortness of breath or fatigue. [well.blogs.nytimes.com]

  […] neurologic disorder (i.e., infantile spasm, seizure, encephalopathy) until condition has stabilized Seizure ≤ three days after receiving DTP or DTaP vaccine Adverse drug reactions Mild reactions include fever, drowsiness, fretfulness, anorexia, headache, fatigue [aafp.org]

  These include paroxysms of coughs proceeded by a whoop, fatigue after these coughing fits and potential vomiting during or after paroxysms. [healio.com]

• Pertussis

  Pertussis (whooping cough). http://www.cdc.gov/pertussis/index.html. Accessed February 13, 2011. 8. Mattoo S, Cherry JD. [aafp.org]

  Pertussis is also changing in other ways. [health.harvard.edu]

  Symptoms and Causative Agent Pertussis, also known as whooping cough, is an extremely contagious disease caused by the Bordetella pertussis bacterium. [historyofvaccines.org]

  See Guidelines for the Public Health Management of Pertussis. Published 11 February 2013 [gov.uk]

  [L. per, very (intensive), + tussis, cough] pertussis (purtus´is), n a disease caused by B. pertussis in which the patient suffers from a cough that makes a “whooping” sound. Also called whooping cough. [medical-dictionary.thefreedictionary.com]

• Cough

  Synonym(s): whooping cough. [L. per, very (intensive), + tussis, cough] pertussis (purtus´is), n a disease caused by B. pertussis in which the patient suffers from a cough that makes a “whooping” sound. Also called whooping cough. [medical-dictionary.thefreedictionary.com]

  Pertussis, also known as whooping cough, is an acute respiratory tract infection that presents as a chronic cough in most patients. [aafp.org]

  Convalescent stage ( weeks to months) Progressive reduction of symptoms Coughing attacks may persist over several weeks before resolving The typical whooping cough manifests mainly in children aged 6 months to 5 years. [amboss.com]

  Initial symptoms may be similar to a cold, with rhinorrhoea and lacrimation, or a dry cough followed by episodes of severe coughing. Fever may be absent or low-grade. [bestpractice.bmj.com]

• Pneumonia

  Furthermore, her hoarseness suggested the possibility of C. pneumoniae, but her C. pneumoniae immunoglobulin-M titer was negative. Because C. pneumoniae was ruled out, her hoarseness suggested a respiratory viral cause. [ncbi.nlm.nih.gov]

  Pneumonia (lung infection) was diagnosed in 2% of those patients. [web.archive.org]

  When to admit/consult local paediatric team: Infants less than 6 months of age Any child with complications (apnoea, cyanosis, pneumonia, encephalopathy) When to consider transfer to tertiary centre: Any child with complications (apnoea, cyanosis, pneumonia [rch.org.au]

  Adult complications Adults are at highest risk for: Bacterial pneumonia Rib fracture Other complications of adult pertussis occur rarely. [studenthealth.oregonstate.edu]

• Sneezing

  MORE INFORMATION ON WHOOPING COUGH Runny nose Sneezing Low grade fever Cough After 1-2 weeks, severe coughing begins. [studenthealth.oregonstate.edu]

  And this is why coughing and sneezing into the elbow instead of the hand, and lots of hand washing is so important. [khanacademy.org]

  Onset of the catarrhal stage is gradual, usually beginning with coryza, sneezing, a dry cough, a slight fever, listlessness, irritability, and anorexia. [medical-dictionary.thefreedictionary.com]

  Initial symptoms include runny nose, sneezing, and a mild cough, which may seem like a typical cold. A mild fever also generally occurs. However, the cough slowly becomes more severe. [historyofvaccines.org]

  To practice good hygiene you should: • Cover your mouth and nose with a tissue when you cough or sneeze • Put your used tissue in the waste basket • Cough or sneeze into your upper sleeve or elbow, not your hands, if you don’t have a tissue • Wash your [nccid.ca]

• Paroxysmal Cough

  In adults with acute (< 3 weeks) or subacute (3-8 weeks) cough, the presence of whooping or posttussive vomiting should rule in a possible diagnosis of pertussis, whereas the lack of a paroxysmal cough or the presence of fever should rule it out. [ncbi.nlm.nih.gov]

  [L. per, very (intensive), + tussis, cough] pertussis /per·tus·sis/ ( per-tus´is ) whooping cough; an infectious disease caused by Bordetella pertussis, marked by catarrh of the respiratory tract and peculiar paroxysms of cough, ending in a prolonged [medical-dictionary.thefreedictionary.com]

  Objective To systematically review the evidence regarding the diagnostic value of 3 classically described symptoms of pertussis: paroxysmal cough, posttussive emesis, and inspiratory whoop. [doi.org]

• Vomiting

  Posttussive vomiting in children was only moderately sensitive (60.0% [95% CI, 40.3-77.0]) and specific (66.0% [95% CI, 52.5-77.3]). [ncbi.nlm.nih.gov]

  Two symptoms, whooping cough and posttussive vomiting, were more sensitive in children than in adults. [doi.org]

  Major complications include pneumonia, encephalitis and malnutrition (due to repeated vomiting). [web.archive.org]

• Gagging

  […] that last for two weeks or longer and may be accompanied by vomiting, gagging, and sticky mucus production. [wellness.ucsd.edu]

  […] discharge, rarely low-grade fever ) Possibly conjunctivitis Paroxysmal stage ( ∼ 2–6 weeks ) Intense paroxysmal coughing (often occurring at night) Followed by a deep and loud inhalation or high-pitched “whooping” sound Accompanied by tongue protrusion, gagging [amboss.com]

  The cough can make a person gag or spit out mucus and make it hard to take a breath preventing enough oxygen from getting to the brain. [saskatchewan.ca]

  Her coughing spells are worse at night and are sometimes associated with gagging and vomiting. Her adolescent son and several of his friends had similar illnesses several weeks before the onset of her symptoms, and they continue to cough. [nejm.org]

  Vomiting frequently occurs after the paroxysms as a result of gagging or choking on the mucus. In infants, choking may be more common than the characteristic whoop. [medical-dictionary.thefreedictionary.com]

• Nausea

  However, many contacts (35%) could not finish a 14-day course despite DOP, mostly because of nausea (85%) or diarrhea (72%). [ncbi.nlm.nih.gov]

  The most common adverse effects associated with clarithromycin include epigastric distress, abdominal cramps, nausea, vomiting, and diarrhea. [cdc.gov]

  […] noticeable, but usually not enough to interfere with daily activities. 34 Here's a list of some common Tdap side effects and the likelihood they may occur: Pain at the injection site Redness or swelling at the injection site Mild fever Headache Tiredness Nausea [soundsofpertussis.com]

  ANTIBIOTICS The American Academy of Pediatrics (AAP) recommends a 14-day erythromycin regimen 22 to treat pertussis, although a seven-day regimen may be as effective. 23 Erythromycin can cause gastrointestinal side effects (e.g., nausea, emesis, diarrhea [aafp.org]

  Possible side effects of whooping cough vaccine may include fever, redness and soreness or swelling where the injection was given, nausea, headache, tiredness and aching muscles. [conditions.health.qld.gov.au]

• Failure to Thrive

  Inpatient care is required for patients with pertussis who have intractable nausea and vomiting, failure to thrive, seizures, or encephalopathy or for patients with sustained hypoxemia during coughing paroxysms who require supplemental oxygen. [emedicine.medscape.com]

• Cyanosis

  We report a 28-day-old female infant with pertussis presenting as severe acute bronchiolitis with cyanosis. On admission, the patient's symptoms were similar to those of acute bronchiolitis. [ncbi.nlm.nih.gov]

  Oxygen may be needed to relieve dyspnea and cyanosis. IV therapy may be necessary when prolonged vomiting interferes with adequate nutrition. [medical-dictionary.thefreedictionary.com]

  Young infants may not develop the typical cough, and often present with apnea and cyanosis instead. The disease is most often diagnosed via laboratory tests, especially detection of B. pertussis in bacterial culture. [amboss.com]

  When to admit/consult local paediatric team: Infants less than 6 months of age Any child with complications (apnoea, cyanosis, pneumonia, encephalopathy) When to consider transfer to tertiary centre: Any child with complications (apnoea, cyanosis, pneumonia [rch.org.au]

• Erythema

  Laryngoscopy showed significant erythema at the medial edges of the vocal folds. Stroboscopy demonstrated bilateral decreased amplitude and decreased mucosal wave of the vocal folds. [ncbi.nlm.nih.gov]

  Local reactions may include pain, skin redness (erythema), and/or swelling. Elevated temperature is a common systemic reaction to the pertussis vaccine. In some rare cases, a fever of over 104.9F degrees has been reported. [rarediseases.org]

  Routine primary immunisation at 6, 10, 14 weeks along with booster doses at 18 months and 5 years are a must.Side effects of vaccination include fever, injection site pain, erythema and irritability. [symptoma.com]

  The limb swelling may be accompanied by erythema, pain and fever. Although the swelling may interfere with walking, most children have no limitation of activity. [web.archive.org]

• Flushing

  Key physical findings in uncomplicated pertussis are: Afebrile, well-appearance between cough episodes Sudden anxious look and explosive burst of coughing on one breath, with flushed face, protruding tongue, and watering eyes Petechiae of conjunctiva [infectiousdiseaseadvisor.com]

• Lacrimation

  Initial symptoms may be similar to a cold, with rhinorrhoea and lacrimation, or a dry cough followed by episodes of severe coughing. Fever may be absent or low-grade. [bestpractice.bmj.com]

  The initial catarrhal stage presents with nonspecific symptoms of malaise, rhinorrhea, sneezing, lacrimation, and mild cough. [aafp.org]

  Infants under 6 months of age rarely "whoop," but may present with apnea, gasping, or gagging -Coughing bouts can occur many times per hour, and may be accompanied by cyanosis, lacrimation, salivation, and post-tussive emesis -Sleep is often interrupted [pedclerk.bsd.uchicago.edu]

  Uncomplicated disease lasts about 6 to 10 wk and consists of 3 stages: Catarrhal Paroxysmal Convalescent The catarrhal stage begins insidiously, generally with sneezing, lacrimation, or other signs of coryza; anorexia; listlessness; and a troublesome, [merckmanuals.com]

• Facial Redness

  During the paroxysm there is marked facial redness or cyanosis and vein distension, the eyes may bulge, the tongue may protrude, and the facial expression usually indicates severe anxiety and distress. [medical-dictionary.thefreedictionary.com]

• Fear

  The physicians did not observe these episodes during daytime examinations, and the basis of the patient's fear of sleep was not explored. [ncbi.nlm.nih.gov]

  Fear and ignorance of hepatitis B and C and HIV make people do such things. The search for parents sharing their situation turned up no formal organization, but they did find lots of other moms and dads searching. [pkids.org]

  And people, I think, were not sophisticated enough to know that a cowpox virus wouldn't make you become a cow, but that was their fear. You could argue that the same fears are alive today. [pbs.org]

  That fear contains a deep irony: The current vaccine, in use for about 20 years, replaced an older and more effective one that went out of use because vaccine critics charged it had too high a rate of side effects. [wired.com]

• Agitation

  Physical examination findings that may be seen: Findings during coughing episodes include - Restlessness and agitation due to prolonged coughing episode with difficulty catching breath. [clinicaladvisor.com]

  […] that the vaccine was associated with minor adverse reactions, including redness and swelling at the injection site and some more serious adverse reactions such as very high fever, prolonged inconsolable crying for hours, hyporesponsive episodes and agitation [healio.com]

• Aura

  […] nature of cough (greater than 75% of patients)—explosive bursts of coughing, all on one breath with intervening minutes or hours without cough Posttussive emesis (approximately 50% of patients) Posttussive whoop (less than or equal to 40% of patients) Aura [infectiousdiseaseadvisor.com]

The diagnosis is suggested after a clinical examination, a characteristic whoop and a history of contact with infected individual will be noted. On examination, a typical whoop will be heard. Patient may be febrile. Signs of coryza will be observed. Conjunctival suffusion and petechia and ulceration of the frenulum of the tongue are usual.

Blood reports will show lymphocytosis due to elaboration of lymphocyte promoting factor which is a characteristic of B. petussis. Lymphocytes may account for 90% of total WBC. Low erythrocyte sedimentation rate (ESR) may be noted.

Specific diagnosis depends upon recovery of pertussis from nasopharyngeal swab or cough plate cultures. Cultures are usually positive in early stage of the disease. Direct fluorescent antibody and counter immune electrophoresis are methods of rapid diagnosis, though these are rarely used in clinical practice.

• Lymphocytosis

  In this age group, high mortality and morbidity have been linked to the effects of the pertussis toxin, including lymphocytosis, pulmonary hyperviscosity and pulmonary hypertension. [ncbi.nlm.nih.gov]

  Morphologic examination of the peripheral blood smear revealed numerous mature lymphocytes with scant cytoplasm, condensed chromatin, and clefted nuclei—characteristic of Bordetella pertussis lymphocytosis. [bloodjournal.org]

Immediate treatment should be started to prevent any respiratory or neurological complications which are serious in infants. Any complication or dehydration is an immediate indication for hospitalisation. Good nutrition and adequate hydration are important.

Antibiotics, mainly erythromycin, should be started early immediately in catarrhal stage as it will abort or reduce the intensity of the infection. It also terminates respiratory tract carriage of pertussis thus reducing the communicability. In the paroxysmal stage, antibiotics have little role to play in altering the course of the disease. Complications should be managed symptomatically [8].

The main objective of treatment is to reduce the spread of infection, ameliorate symptoms and prevent further compications. Thus, with proper diagnosis and prompt treatment the outlook of pertussis is very good with complete recovery. The chronic cough will resolve within 3 months.

Recurrence of cough and symptoms may occur after 6 months. In adolescents, adults and a little older children prognosis [6] is very good. Infants less than a year have a higher risk of complications, mainly bacterial pneumonia. Mortality of pertussis is mainly due to infants who have not received vaccination [7].

The causative agent of this infection is Bordetella pertussis which is a Gram-negative coccobacillus. These bacteria are spread by droplet infection, as a result of an infected person’s sneeze or cough, these droplets are released in the air. This is a highly infectious disease which spreads to infants or children through the family members who may not even be aware of the infection. On inhalation of this infection, the bacteria attach to the nasopharyngeal epithelium, proliferate and spread through the ciliated epithelium.

There are a number of risk factors which facilitate its transmission, mainly individuals who are not immunised, infants and children who are in close contact with infected people and parents who refuse to give vaccination to their children due to misconceptions [2].

Health care providers who are in close contact with infected individuals are also at a risk. In case of an epidemic outbreak, all individuals staying in crowded areas, schools or hospitals are at high risk of contracting this infection.

Pertussis occurs worldwide and continues to be a global problem in spite of vaccination being widely available. The post vaccination era has seen a 20 fold decline in the incidence. Periodic epidemics [3] however continue to occur worldwide.

Recent studies from WHO suggested that 260,000 children under the age of 5 years die from pertussis every year. Thus in spite of primary vaccination, pertussis continues to be a health hazard. Prior to vaccination, pertussis was a common cause of illness and death.

Pertussis occurs all throughout the year but is noticed more in summer. Pertussis affects all ages, males and females are equally affected. Children and infants are affected more, especially in the age range from 6 months to a year. A study in Australia reported that adults with obesity or asthma were more likely to have pertussis [4].

With improved vaccines, cases have been reported more in adults and adolescents. Infants maybe infected before vaccination. Alternatively, post vaccination immunity may wane in older children, who may suffer from a mild or modified form of the disease which is difficult to recognize.

The organism is spread by droplets from infected, untreated patients. Pertussis main pathogenesis is due to the toxin that it elaborates. Clinical features depend upon the host response to various antigens, the capsule, cell wall and cytoplasm of the organism.

The bacterium gets adhered to the respiratory epithelium and destroys the ciliated epithelium which results in the first catarrhal stage. A lymphocytosis promoting factor probably plays an important role. Endotoxin does not seem to contribute to the pathogenesis. Bacteria also seem to invade the tissue and are seen in alveolar macrophages.

Pathological changes induce inflammation of the mucosal lining of the respiratory tract. Debris gets accumulated in the respiratory tract. Bronchopneumonia develops, with necrosis and desquamation of the superficial epithelium of the bronchi.
Bronchiolar obstruction and atelectasis can result from accumulation of secretions. Bronchiectasis may develop and persist. Due to accumulation of mucus secretions, coughing occurs.

Changes in brain and liver are seen in severe disease especially in infants and the cause is anoxia. The bacteria are not detected in blood culture [5].

Strict respiratory isolation is desirable for 6-7 days after starting antibiotic therapy, thus reducing contact with other indiviuals. Chemoprophylaxis with erythromycin is ideal for immunised contacts under 2 years of age.

Routine primary immunisation at 6, 10, 14 weeks along with booster doses at 18 months and 5 years are a must [9].
Side effects of vaccination include fever, injection site pain, erythema and irritability.

All health care professionals should also take the vaccine.
Pertussis is an easily preventable disease as effective active immunisation is available [10].

Pertussis is an acute infectious disease caused by Bordetella pertussis. B. pertussis [1] is a Gram-negative coccobacillus. This is a serious infection common in infancy and childhood with serious complications. Pertussis occurs worldwide and epidemic outbreaks are common. Humans are both natural hosts and reservoirs of this infection.

Pertussis is highly communicable and spreads by droplet infection. It is also known as whooping cough or ‘cough of 100 days’. The symptoms at the start are mild and can be confused with other upper respiratory infections. It presents in 3 stages where it starts with an inflammatory coryza and later progresses onto severe episodes of coughing spasms.

Prevention is in the form of vaccination which is of great importance especially in children due to severity of secondary bacterial infections. The mainstay of treatment is antibiotics to reduce the severity of the disease.

It is known as whooping cough for the distinct ’whoop’ sound produced while coughing which is of a very high pitch and usually occurs when inhalation is attempted.

Pertussis or whooping cough is an acute infectious disease caused by a bacterium called as Bordetella pertussis. This is a highly contagious disease spread by close contact, sneezing, and coughing. This infection results in severe violent episodes of coughing with a characteristic whoop sound when the patient attempts to breathe.

The bacteria can cause a serious upper respiratory tract infection especially in infants which can result in severe complications and can even be fatal. When an infected person sneezes or coughs, small mucus droplets containing the Bordetella pertussis bacteria get released and the infection easily spreads to other people.

This infection persists for at least 6-8 weeks. It starts with symptoms similar to common cold and later on progresses to severe episodes of spasmodic coughing which are uncontrollable. Coughing can end in vomiting.

Immediate medical care should be provided as it helps to reduce the transmission of this infection as well as reduces severity and the complications which can occur. Antibiotics are started and infected individuals are kept separate especially away from infants and non-vaccinated individuals.

Blood tests are done but diagnosis is usually made after a good clinical examination. Infants need strict supervision as they have the highest risk of developing respiratory complications.

Prevention is the best approach for this disease. Vaccination is the most effective way of prevention against pertussis. All children should be vaccinated according to the immunisation schedule regularly. Booster doses should also be given. Adults above 65 years can take the adult vaccine especially in case of a pertussis epidemic.

With prompt antibiotics there is complete recovery. Pertussis has a good outlook provided immunisation is followed.

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