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

Objectives

Enhance East Central Public Health District VI’s 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

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 School…highly 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

Resurgence of Pertussis

Mutation

Waning vaccine-induced immunity 5 to 7 years after vaccination, leaving adolescents and adults unprotected

Waning disease-induced immunity doesn’t last much longer than that of vaccination

Enhanced identification: Public health awareness, surveillance, diagnostic programs

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 4–22

times more common than symptomatic infections

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)

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)

Clinical Symptoms in Infants

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

Infant Complications Seizures (3%) Pneumonia (22%) Encephalopathy (1%) Death Case fatality rate: 1.3% in infants <1 month

0.3% in infants 2-11 months

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 don’t 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

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

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

Prevention - Terms

Tetanus Diphtheria (Td)

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

Prevention = Immunization

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

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 <12 months of age

May give Tdap within 2 year intervals to protect against pertussis

Tdap is not licensed for adults >65 years

Contraindications and Precautions

Contraindications to Tdap History of serious allergic reaction

(anaphylaxis) to vaccine components

History of encephalopathy not attributableto 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

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; 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

Questions?