Duration of Protection After First Dose of Acellular Pertussis Vaccine in Infants

PERTUSSIS

PERTUSSIS

an acute respiratory tract infection that was described by Sydenham as pertussis, meaning intense cough, it is preferable to whooping cough because most infected individuals do not “whoop.”

ETIOLOGY

Bordetella pertussis .

Bordetella parapertussis that contributes significantly to 5% of pertussis.

All are gram-negative coccobacilli that are recovered best on Bordet- Gengou media.

In very young children, the prolonged coughing fits and vomiting can interfere with sleeping and feeding patterns.

EPIDEMIOLOGY

Spread by direct contact or droplet infections during cough.

Infants less than one year of age constitute 50-70% of diagnosed cases.

DROPLET PRECAUTIONS Surgical mask ( N 95 not necessary)

Gloves / Consider Gown

Frequent hand washing

Transmission risk within ~ 3 feet or less of a cough , sneeze, face to face talking .

PERIOD OF COMMUNICABILITY

The disease occurs 3-12 days after exposure to an infected individual

The coughing stage lasts for approximately six weeks before subsiding. In some countries, this disease is called the 100 days' cough or cough of 100 days .

CLINICAL MANIFESTATIONS

The incubation period of pertussis has a mean of 7 and a range of 6-20 days.

Classically, divided into:1- Catarrhal, 2- Paroxysmal, and 3- Convalescent stages.

CATARRHAL STAGE

The term "catarrh" meaning"to flow."  Nasal congestion Runny nose Mild fever Eye redness and excess eye watering

PAROXYSMAL STAGE (2-4WK)

The term "paroxysm" means a sudden, violent burst.  The paroxysms or "fits" of coughing may...

start as a dry, intermittent, annoying cough that

increases in intensity and frequency

occur at least once an hour

cause the child to turn red, blue, or purple

CONTD….

cause the eyes to bulge and water excessively

cause significant distress in the child

vomiting after coughing

CONT……..

Young infants may have small bursts of cough or no cough before developing...

Gasping Choking Turning red, blue or purple Apnea (episodes of not breathing)

CONVALESCENT STAGE (≥2 WK)

The coughing fits become less frequent and less intense.  Young infants may develop louder coughing but typically the breathing difficulty improves.

DIAGNOSIS

Clinical diagnosis is during paroxysmal stage. H/O incomplete vaccination. H/o contact. CBC shows leukocytosis. Fluorescent antibody staining of

nasopharyngeal secretions. nasopharyngeal swab. X-ray chest

TREATMENT

Hospitalization is especially for infants less than 6 months. 

supplemental oxygen or even mechanical venitlation may be necessary for severe disease. 

All individuals with confirmed pertussis should be treated with antibiotics such as erythromycin, azithromycin or clarithromycin. 

  Antibiotics reduce the severity of illness and also reduce the spread of the illness.

ANTIBIOTICS

Erythromycin [50mg/kg/day] for 14 days may eliminate pertussis organisms from the nasopharynx within 3-4 days.

Supportive care : avoidance of factors that provoke attacks of coughing,

maintenance of the hydration and nutrition, oxygen if there is distress, gentle suction for

viscid secretions.

COMPLICATIONS

Infants less than 6 months of age are at the highest risk for complications.  These include:

Apnea Ear infections Pneumonia Seizures Encephalopathy Death (approximately 1% of infants less than

2 months of age)

SHOULD EXPOSED FAMILY MEMBERS BE TREATED?

Yes. 

Family members and close contacts of an infected child should be treated with antibiotics to prevent spread of the illness.

  This is true even for vaccinated individuals. 

ISOLATION

Patients with suspected pertussis are placed in respiratory isolation with use of masks by all health care personnel entering the room.

Screening for cough should be performed and isolation until 5 days after initiation of macrolide therapy.

COND….

Children and staff with pertussis in child-care facilities or schools should be excluded until macrolide prophylaxis has been taken for 5 days.

CAN PERTUSSIS BE PREVENTED?

The pertussive vaccine is effective for at least 5 years. 

This helps prevent infection in the age group where pertussis infection is most severe. 

The pertussis vaccine is part of the DTaP vaccine (along with tetanus and diphtheria). 

VACCINATION SCHEDULE

The DTaP vaccine should be given in five doses

at ages 2 months, 4 months, 6 months, 15 to 18 months, and 4 to 6 years.

  A booster dose is recommended at 11 to 12 years of age.

DTaP VaccineTdap Vaccine

WHAT KIND OF VACCINE IS DTAP? The diphtheria and tetanus components are

inactivated toxins called a toxoids.

For the pertussis component of DTaP and Tdap vaccines, purified components of the bacterium are grown and then inactivated.

HOW IS THIS VACCINE GIVEN?

The DTaP vaccine is given as an Intramuscular injection.

Dose is .5ml

FOR CHILDREN, HOW MANY DOSES OF DTAP VACCINE ARE REQUIRED?

Children up 2 months – 6 years: A series of 4 doses given at 2, 4, 6, and 15-18

months of age.

A 5th shot, or booster dose, is recommended at 4-6 years of age, unless the fourth dose was given late (after the fourth birthday).

A booster dose of Td (adult tetanus and diphtheria) is recommended every ten years. The new Tdap vaccine can be substituted for one booster dose of adult Td.

SHOULD ADULTS WHO WEREN'T IMMUNIZED AS CHILDREN RECEIVE THIS VACCINE AS ADULTS?

Children 7 years and older without documentation of DTaP vaccination should receive a primary series of three doses of Tetanus-diphtheria toxoid (Td).

The first 2 doses should be separated by 4 - 8 weeks, and the 3rd dose given 6 - 12 months after the second dose.

Tdap vaccine can be substituted for one of these three doses, preferably the first dose for persons 11 years and older.

HOW SAFE IS THIS VACCINE

The most common reactions are

Soreness, redness, and swelling at the injection site.

Mild feverLoss of appetiteTirednessVomiting

WHO SHOULD NOT RECEIVE VACCINE?

People who have had a serious allergic reaction to one dose of DTaP, DT, Td, or Tdap vaccine.

Persons with a moderate or severe illness should postpone receiving the vaccine until their condition has improved.

WHAT ADVERSE SIDE EFFECTS HAVE BEEN REPORTED WITH THIS VACCINE?

Moderate to serious reactions include: Crying for three hours or more

High fever

Collapse or shock-like state

Convulsions within three days

VACCINES IN PAKISTAN

DPT +Tetanus+, Pertussis  Hep B + Hemophilus Influenza

QuinvaxemNovartis

Free from Govt./Also available in private market for Rs 1800/-

Diptheria, Tetanus, Pertussis, Polio, Hepatitis B, and Haemophilus Influenzae B Vaccine

Infanrix Hexa Glaxo Smith KlineRs.1750/-

Pertussis VaccineAcelluvax

Chiron Biocine NovartisRs. 1490/-

Duration of Protection After First Dose of Acellular Pertussis Vaccine in Infants

published online February 10, 2014;

Type of study case-control study.

Place of study Australia.

INCLUSION CRITERIA aged 2 to 47 months between January 2005 and December 2009

to controls from a population based immunization register by date of birth and region of residence .

coughing illness lasting 2 weeks. detection by polymerase chain reaction [PCR]

test or isolation by culture or suggestive laboratory

CASES

All pertussis notifications for children aged,4 years with a diagnosis

date between January 1, 1995 and December

31, 2010 were included.

EXCLUSION CRITERIA

Cases where immunization status was not recorded in the notification data set supplied

by states and territories were excluded

Any doses received by a control after the date of disease onset in their matched case were not included in the total..

5226 notified cases. 642 were excluded. 4584 cases for matched analysis.

STATICALLY DATA

were performed using the Pearson x2 test and a significance level of P <.05.

The model was stratified by the age groups to estimate the odds

ratio (OR) for receipt of 1, 2, or 3 vaccine doses for notified pertussis cases compared with their matched controls.

DISCUSSION

we sampled 20 age-matched controlsfor each case to maximize precision.We selected eligible controls bornon the day before or the day after thebirth date of the index case to ensurethat cases were not matched to themselves.The vaccination status of controlswas ascertained using the ACIR.

National data from the ACIR between 2000 and 2010 showed that after 2 months

of age, the proportion of children aged up to 12 months recorded as having received no doses of DTaP remained nearly constant, with the first dose received before 3 months of age in 87% .

PERTUSSIS NOTIFICATION RATES IN CHILDREN AGED <4 YEARS, 1995–2010, AUSTRALIA.

PERTUSSIS HOSPITALIZATION RATES IN CHILDREN AGED <4 YEARS, 1995–2010, AUSTRALIA.

WHAT’S KNOWN ON THIS SUBJECT:

Waning effectiveness of 5 doses of acellular pertussis vaccines is well documented after 6

years of age, but data are lacking for fewer doses in younger children.

WHAT THIS STUDY ADDS:

In 2- to 3-month-old infants, 1 dose of the diphtheria–tetanus–acellular pertussis

vaccine gave significant protection against hospitalized

pertussis. The effectiveness of 3 doses decreased

from 84% between 6 and 11months to 59% after 3

years.

STRONG POINTS OF STUDY

largest reported observational study . both against severe disease in infants and

against all laboratory-confirmed pertussis. We had large numbers of cases. much greater sensitivity

LIMITATIONS OF STUDY

the lack of gender specification. socioeconomic data for cases and controls.

CONCLUSIONS

DTaP provided good protection against pertussis in the first year of life from the first dose. Without a booster dose, the effectiveness of 3 doses waned more rapidly from 2 to 4 years of age than previously documented for children .6 years of age who had received 5 doses.

ANNUALLY REPORTED CASES

Pakistan Source from W.H.O Cases reported 4,334 Total population 159,196,3362