A new study found that newborns diagnosed with whooping cough or pertussis most likely contracted the bacteria from their siblings, and not from their mothers as widely believed.
Pertussis is a respiratory infection caused by the bacteria Bordetella pertussis. The disease may be hard to control and is most rampant in terms of morbidity and mortality rates among infants. The actual source of pertussis in young infants is often not clearly identified but when the clinicians do, the mothers are the most typical reservoir. However, the increasing rate of whooping cough amid maternal vaccination has urged experts to investigate whether there has been a change in the source of infection among infants in the U.S.
The researchers from different government and academic institutions in the U.S. conducted the study by identifying patients with pertussis aged less than one year old from Enhanced Pertussis Surveillance sites from the period of Jan. 1, 2006 to Dec. 31, 2013. The source of infection (SOI) was determined during the patient interview session. SOI is defined as the probable case of pertussis that had come in contact with an infant with confirmed diagnosis, seven-20 days prior to the start of cough.
The findings of the study, published in the journal Pediatrics, showed that out of the 1,306 identified cases, SOI was determined in 569 and was more noted in infants less than two months compared to those aged between two-11 months, with 54.1 percent and 40.2 percent ratings respectively. The researchers particularly found that greater than 66 percent of SOIs were from the immediate kin, of whom 35.5 percent were siblings, 20.6 were mothers and 10 percent were fathers.
The researchers were able to establish a contrast between the previous belief that most SOIs were mothers and the present findings that there have been changes in the epidemiological data of pertussis. Monitoring SOIs will help alleviate the problem of increasing pertussis cases; however, experts suggest that prenatal immunization should be practiced as this can provide direct protection for infants against the causative bacteria.
In the U.S., only 15 percent of pregnant women obtain vaccines for whooping cough prevention, says Tami H. Skoff, an epidemiologist from the Centers for Disease Control and Prevention. While mothers infected with pertussis may not transmit the bacteria to their fetuses, coughing during the delivery process may transmit the disease to the newborn. Therefore, maternal vaccination serves a double purpose as both the mother and infant becomes protected from the disease.
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