Related Experiment Video
Updated: Apr 16, 2026
Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice
Published on: February 22, 2019
Pertussis in infants under one year old: risk markers and vaccination status--a case-control study
Chen Stein Zamir1, Dana Bardugo Dahan1, Hanna Shoob2
1Jerusalem District Health Office, Ministry of health, Jerusalem, Israel; Braun School of Public Health and Community Medicine, The Hebrew University and Hadassah, Jerusalem, Israel.
Insights
Infants with low birthweight and high birth order are at increased risk for pertussis. Pertussis vaccination significantly reduces risk, with effectiveness increasing with each dose.
Area of Science:
- Pediatrics
- Infectious Diseases
- Epidemiology
Background:
- Pertussis (whooping cough) poses a significant health burden, particularly for young infants.
- Infants under one year are most vulnerable to pertussis-related complications and mortality.
Purpose of the Study:
- To identify risk markers for pertussis in infants.
- To evaluate the vaccination status and vaccine effectiveness in preventing pertussis in infants.
Main Methods:
- A case-control study matched 317 infants with pertussis to 951 controls in Jerusalem (1998-2011).
- Data included epidemiological investigations, health records, and DTaP/DTP vaccination records.
- Vaccine effectiveness was calculated based on the number and timeliness of vaccine doses received.
Main Results:
- Low birthweight and high birth order (4th+) were independent risk markers for pertussis.
- Male gender and lower socioeconomic status were more prevalent in pertussis cases.
- Vaccine effectiveness was 72.9% for the first dose, 76.1% for the second, and 84.4% for the third dose. Delayed vaccination was more common in cases.
Conclusions:
- Low birthweight and high birth order are key risk factors for infant pertussis.
- Pertussis vaccination is highly effective, with increasing protection after each dose.
- Ensuring timely infant vaccination is crucial for preventing pertussis.
Background:
Pertussis is a contagious bacterial disease causing substantial health burden. Pertussis-related morbidity and mortality are highest in young infants. We investigated risk markers for pertussis and vaccination status in infants.
Methods:
Reported pertussis cases under one year old during 1998-2011 in the Jerusalem district were matched to controls by birthdate and residence. Data sources included epidemiological investigations, health records and vaccination records (number and dates of DTP\DTaP doses scheduled at 2, 4, 6 months). Vaccine effectiveness was calculated by number of vaccine doses stratified by age group. Timeliness of vaccine doses was also evaluated.
Results:
The study population included 1268 infants under 1 year: 317 pertussis cases and 951 age-matched controls (mean age 3.95±3, median 2.9 months). Low birthweight (<2500g, 12.3% in cases vs. 6.3% in controls) and high birth order (4th and above) were found to be independent risk markers. Male gender and low socio-economic status were more frequent among cases. Some 40% of the cases (127/317) were hospitalized, most of them (111/127, 87.4%) were under 4 months (mean age 2.42±2.05, median 1.8 months). The distribution of the number of pertussis vaccine doses 0, 1, 2 and 3 differed considerably being 42.2%, 32.7%, 15.6%, 9.5% vs. 13.7%, 41.9%, 22.9%, 21.5% among cases and controls (≥2m), respectively. The overall vaccine effectiveness found was 72.9%, 76.1% and 84.4%, for the 1st, 2nd and 3rd doses of a pertussis vaccine. The infant's age at the first dose of pertussis vaccine was recorded with follow-up until age 18 months. Delay was more common among cases with a lower proportion vaccinated-78.9% at 18 months vs. 99% in controls.
Conclusions:
Specific risk markers for pertussis in young infants were identified. Reported pertussis cases over age 2 months were significantly more likely to be unvaccinated and have delayed vaccinations. The vaccine effectiveness increased with the number of vaccine doses.
More Related Videos
11:32Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
05:31Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels
Published on: August 7, 2017
Related Concept Videos
01:51Vaccinations
01:29Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
01:25Transmission-based Precautions II: Airborne and Protective Environment
Airborne precautions:
Use airborne precautions when treating patients known or suspected to have diseases that spread through the air—for example, tuberculosis or measles. These organisms are present in smaller droplets expelled by an infected person and...
01:30Pneumonia I: Introduction
Risk Factors
Various factors influence the likelihood of developing pneumonia. Age plays a crucial role, with infants, children under two, and individuals over 65 at increased risk due to their...
01:26Factors Affecting the Risk of Infection
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin...
01:30Pneumonia V: Nursing management and Prevention
The nurse must practice strict medical asepsis and adhere to infection control guidelines to minimize healthcare-associated infections.
Enhance airway patency
Position the patient correctly to facilitate drainage of the affected lung segments. Manual or mechanical percussion and vibration can also be employed....