Pertussis (whooping cough)

Pertussis : Highly contagious respiratory infection caused by Bordetella pertussis�
Outbreaks first described in 16th century�
Bordetella pertussis isolated in 1906�
Estimated >300,000 deaths annually worldwide
Before the availability of pertussis vaccine in the 1940s, public health experts reported more than 200,000 cases of pertussis annually.
Since widespread use of the vaccine began, incidence has decreased more than 75% compared with the pre-vaccine era.
In 2012, the last peak year, CDC reported 48,277 cases of pertussis.
Extremely contagious-attack rate 100%
Immunity is never complete
Protection begins to wane in 3-5 yrs after vaccination

1. Pertussis Whooping cough BY : MUSTAFA KHALIL IBRAHIM T bilisi S tate M edical U niversity 6 th Year, 1 st Semester, 1 st Group pediatric infectious diseases

2. Before the availability of pertussis vaccine in the 1940s, public health experts reported more than 200,000 cases of pertussis annually. Since widespread use of the vaccine began, incidence has decreased more than 75% compared with the pre-vaccine era . In 2012, the last peak year, CDC reported 48,277 cases of pertussis. Extremely contagious-attack rate 100% Immunity is never complete Protection begins to wane in 3-5 yrs after vaccination EPIDEMIOLOGY:

3. Pertussis : Highly contagious respiratory infection caused by Bordetella pertussis Outbreaks first described in 16th century Bordetella pertussis isolated in 1906 Estimated >300,000 deaths annually worldwide DEFINITION

4. Bordetella Pertussis Bacterial 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 4–22 times more common than symptomatic infections. Rarely : B.Parapertussis B. Bronchiseptica ETIOLOGY

5. Close person to person contact via aerosolized droplets from respiratory secretions of patients with disease. 90% of non immune 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 ). TRANSMISSION

6. Pertussis is primarily a toxin-mediated disease. The bacteria attach to the cilia of the respiratory epithelial cells, produce toxins that paralyze the cilia, and cause inflammation of the respiratory tract, which interferes with the clearing of pulmonary secretions . Until recently, scientists thought that  B. pertussis did not invade the tissues; however, recent studies have suggested that the bacteria are present in alveolar macrophages . PATHOGENESIS

7. 10 20 Incubation (days) catarrhal paroxysmal convalescent 1 to 2 weeks 3 to 6 weeks 1 to 12 weeks Atypical cough Rhinorrhea 7 to 10d 5 coughs Choking Vomiting Whooping 15 Adapted from Wirsing von konig CH. et al., Lancet Infectious Disease 2002 ; 2 (12 ) : 744—50; Heininger U. and Cherry JD., Expert Opin.Biol. Ther. 2006; 6 (7):685-697. SIGNS & SYMPTOMS

8. Nonspecific features. Congestion, Rhinorrhoea . Sneezing. Lacrimation, Conjunctival redness. Low grade fever, mild cough. Cold-like ( coryza , conjunctival irritation, occasionally a slight cough ). Duration ~ 7-10 days. Catarrhal stage:

9. Long duration (3-6 weeks); No fever, most contagious period . a series of rapid, forced expirations, followed by gasping inhalation  the typical whooping sound. vomiting common, in Very young infants may present with apnea or cyanosis in the absence of cough. Series of coughing in single expiration which is first dry & intermittent. Eyes bulging—watering. Chin & Chest held forward. Tongue protruding maximally. Face-Red-Blue. Whoop at the end of paroxysm. Paroxysmal stage

10. Episodes of cough becomes less frequent. Less severe. Paroxysms of whooping disappear. Convalescence

11. Most severe in infants <6 months. Atypical presentation. Apnea most common symptom. Whoop is absent. Hospitalization often needed. Lymphocyte predominant, increased white count can match severity of the cough. No classical stages well appearing infants begins to choke Gasp & flail extremities. Cough may not be prominent . SYMPTOMS IN INFANTS

12. Fever. Malaise, Myalgias . Rash. Sore throat. Hoarseness. Tachypnea. Wheeze. Crepitations/ Rales. HOW TO SUSPECT ?

13. 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 . Blood Count Absolute Lymphocytosis ( 15,000-100,000 cells/mm 3 ( . Cultures : nasopharyngeal (NP) swab or aspirate from all persons with suspected cases. X-Ray chest DIAGNOSIS

14. Adenoviral respiratory infection - Children present with fever, sore throat, and conjunctivitis. Mycoplasmal pneumonia - Patients with mycoplasmal infections have more pronounced systemic symptoms, fever and headache may occur, and rales may be appreciated on chest auscultation. Chlamydial pneumonia - Young infants with chlamydial infections present with staccato cough, purulent conjunctival discharge, tachypnea, rales , and wheezing. Respiratory syncytial virus infection - Patients present with predominantly lower respiratory tract signs ( eg , wheezing, rales ). DIFFERENTIALDIAGNOSIS

15. COMPLICATIONS OTHRES CNS FORCEFUL COUGH RESPIRATORY Death. Hospitalization. Cyanosis. Weight loss. Urinary incontinence. Syncope. inguinal hernia. Cardiogenic Shock . Convulsions….. Hypoxemia, hemorrhage. Encephalopathy seizures Epistaxis, sub- conjunctival hemorrhage. Intracranial bleeding . Rectal prolapse, umbilical hernias. Dehydration, malnutrition Rib fractures from severe coughing. Tetany. Apnea. Bronchopneumonia. Atelectasis. Bronchiectasis. Emphysema—interstitial / subcutaneous. Otitis media. Reactivation of quiescent tuberculosis. Pneumonia. Pneumothorax.

16. COMPLICATIONS BY AGE

17. 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 . TREATMENT

18. Hospitalized patients need to be on Droplet Isolation for 5 days after therapy. Monitor exposed children for respiratory symptoms for 20 days: Adequate hydration, Nutrition Oxygen Gentle suction Cough syrup have no role Laboratory confirmation is difficult, so diagnosis often based on characteristic clinical manifestations. Children may return to school after 5 days of appropriate antibiotic therapy. SUPPORTIVE CARE

19. Pertussis vaccine is part of DTaP vaccine . All household contacts should get Erythromycin for 14 days . Close contacts < 7 yr should get booster . If documented pertussis infection exempt from routine pertussis vaccination . CDC also recommends Tdap for pregnant women during each pregnancy, with a preferred administration during the early part of gestational weeks 27 through 36. PREVENTION

20. Universal immunization of all children <7 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. PREVENTION = IMMUNIZATION

21. 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. Contraindications and Precautions

22. 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; 25:4:361-362 Pickering, LK. Pertussis.The Red Book. 2003; 26:472-486 Gilbert, D.N. The Sanford Guide to Antimicrobial Therapy. 2005; 35:24 https:// www.cdc.gov/pertussis/index.html REFERENCES :