There is not sufficient data to prove a mother-to-child transmission of the novel coronavirus, experts said in Beijing on Friday.

Cases of newborns infected with the novel coronavirus raises the question of whether mother-to-child transmission through the placenta can take place. Objectively speaking, current data is not sufficient to support that conclusion, said Wang Guiqiang, a member of the Society of Infectious Diseases of the Chinese Medical Association.

Earlier, two newborns were confirmed to be infected with the novel coronavirus in Wuhan Children's Hospital, Hubei province, the outbreak center, with the age of 30 hours old and 17 days old. The mothers of the two were also diagnosed as infected.

The child may be in contact with maternal secretions during the delivery, Wang said. In this case, contact transmission may be more important. At present, the novel coronavirus is a mainly respiratory virus; a few patients may have the virus in the intestinal tract, but the nucleic acid test didn't reveal this, he added.

"If there is mother-to-child transmission through the placental barrier, it needs a high concentration of the virus in the blood," Wang said. "But the positive rate of nucleic acid testing in the blood is not high."

Preliminary findings suggest exposure to newborns is more likely to cause the transmission, but further study is needed, Wang added.

The youngest newborn was born on Feb 2 to a mother who was diagnosed with the novel coronavirus. To avoid the influence of amniotic fluid and other factors, a coronavirus nucleic acid test was conducted 30 hours after birth and showed infection.

The 17-day-old newborn was born on Jan 13 in good condition. A maternity matron visited the family on Jan 22, and the mother was diagnosed as infected later. The baby was diagnosed on Jan 31. It can be confirmed this baby was in close contact with the infected, which suggests newborns can also be infected.