The Pediatric Infectious Disease Journal
Issue: Volume 27(6), June 2008, pp 557-558
Human Papillomavirus DNA Detected in Breast Milk
Sarkola, Marja MD*†; Rintala, Marjut MD, PhD†; Grénman, Seija MD, PhD†; Syrjänen, Stina DDS, PhD*
From the *MediCity Research Laboratory and Department of Oral Pathology, Institute of Dentistry, Faculty of Medicine, University of Turku; and †Department of Obstetrics and Gynaecology, University Central Hospital, Turku, Finland.
Accepted for publication January 21, 2008.
This study was supported by Päivikki and Sakari Sohlberg Foundation, Helsinki, Finland and the Governmental Special Foundation for Turku University Central Hospital, Finland.
Address for correspondence: Stina Syrjänen, DDS, PhD, Department of Oral Pathology, Institute of Dentistry, Faculty of Medicine, University of Turku, Lemminkäisenkatu 2, FI 20520, Turku. E-mail: firstname.lastname@example.org.
Human papillomavirus (HPV) testing of 223 breast milk samples 3 days postpartum was performed with polymerase chain reaction, hybridization, and sequencing. HPV-16-DNA was detected in 4.0% of the samples. HPV carriage in the breast milk was not correlated with mother’s oral or cervical HPV-status or the demographic data. Oral HPV-infection of the spouse at month 6 and 12 postpartum was statistically significantly associated with HPV carriage in the breast milk.
Several viruses have been detected in human milk, and some viruses like human immunodeficiency virus (HIV)-1 can infect the newborn.1 The presence of human papillomavirus (HPV) in breast milk has not been previously assessed. HPV is known to infect oral mucosa of infants.2 HPV might infect the epithelium of the nipple and areola.3 HPV replication in the primary human mammary ductal epithelial cells has been demonstrated (P.L. Hermonat, personal communication), and HPV types 16 and 18 can immortalize normal breast epithelium in vitro.4 Contradictory results exist on HPV detection in breast carcinomas.5
The Finnish HPV Family Study is a prospective follow-up cohort study started in 1998 to evaluate the transmission modes of HPV between newborn babies and their parents.6,7 Here we present the results of HPV-DNA testing in breast milk samples taken 3 days after delivery. The results were correlated with the earlier published data on oral and cervical HPV carriage of the spouses during a 1-year follow-up period.6,7
We studied 223 mothers and 87 fathers. The mean ages of the mothers and the fathers were 25.1 years (range, 18–38 years) and 28.8 years (range, 19–46 years), respectively. At first visit after delivery, the spouses filled in questionnaires concerning their risk factors for HPV infection. Overall, 24% and 7% of the mothers and fathers reported previous genital warts and 3% and 2% had previous oral warts, respectively. Samples. Mothers collected the milk samples manually 3 days postpartum in the hospital into a 3 mL plastic container after washing hands with disinfectant. This procedure was done apart from feeding the infant. The container was sealed by a midwife trained for the project and the samples were immediately frozen and stored at -70°C. The milk samples were centrifuged for 20 minutes at 3000 rpm to pellet the cells, from which the DNA was extracted with the high pure polymerase chain reaction (PCR) template preparation kit (Roche Diagnostics GmbH, Penzberg, Germany), according to the manufacturer’s instructions. To control the quality of extracted DNA, the human [beta]-globin gene was first amplified with PCR from eleven samples. Oral and cervical scrapings were taken before delivery, at month 2, 6, and 12 as described earlier.6