A couple from Iowa has a warning for parents.

Don’t let people kiss your newborn infant.

The couple began cautioning other parents after their from viral meningitis at 18 days old.

Mariana Sifrit contracted viral meningitis caused by the herpes virus HSV-1 when she was less than a week old.

It is believed she contracted the virus from a kiss.

Dr. Karin Nielsen is a clinical professor of pediatrics in the division of infectious diseases at the David Geffen School of Medicine at UCLA.

She said infants are particularly vulnerable to HSV-1, which can cause cold sores.

“In the specific situation of herpes simplex virus or HSV, some people may have cold sores around their lips, or just start manifesting them, and kissing can transmit the virus to others, particularly to infants, who are more susceptible as they have no prior immunity,” Nielsen told Healthline.

“If someone with active HSV infection … kisses a baby, there is indeed a significant risk, especially during the newborn period,” she added.

Infants are vulnerable

So how careful do parents need to be?

Dr. Dean Blumberg is the chief of pediatric infectious diseases at the University of California Davis Children’s Hospital.

He said parents need to be particularly vigilant when their babies are still only a few months old.

“The immune system becomes stronger and matures with age,” Blumberg told Healthline. “Children are particularly vulnerable to severe infections in the first month of life, and may have particularly serious infections in the first three months of life with few symptoms except for fever.”

Viral meningitis is just one of the illnesses that can prove fatal to newborns.

Nielsen said that before children are immunized, they can catch any illnesses that are preventable by vaccines.

Influenza, whooping cough, and other respiratory viruses are some of the diseases that can be serious for babies.

Advice for parents

Nielsen emphasized that parents should simply exercise common sense when dealing with their newborns.

She advised parents to avoid taking infants to crowded spaces full of people, and avoid having too many visitors during the baby’s first month of life.

She also said that parents should avoid close contact with other young children or always have them wash their hands before handling the baby.

People who are displaying any signs of illness like cough, runny nose, sore throat, or a rash should not come into close contact with a newborn.

“The newborn period is not the time to try to build immunity,” she said. “It is the time to protect newborns from others who are sick. It is the time to stimulate bonding between the infant and the parents, and a time of significant adaptation. As such it should be a quiet time with few visitors and a time for parents to spend time at home with their babies as they develop their routines and their schedules.”

Blumberg conceded that many new parents will struggle to keep well-meaning visitors to a minimum.

“This is a difficult issue because there are many family and cultural expectations that need to be balanced by limiting exposure to possible infections. I do not recommend limiting to any specific number of visitors. Instead, make sure that all visitors are immunized and healthy,” he said.

Watch for symptoms

Blumberg also advised that parents should keep an eye out for particular symptoms in babies that could indicate serious illness.

“Any fever in the first month of life could indicate a serious infection,” he said. “See your healthcare provider if the rectal temperature is 100.4°F [38°C] or greater. Other concerning signs or symptoms include any difficulty breathing, vomiting, diarrhea, poor feeding that leads to weight loss, decreased urination and possible dehydration, and development of a rash without a known cause,” he said.

“Infants with serious infections will stop eating, will not wake up, or may become extremely irritable,” Nielsen added.

“They may have seizures [repetitive movements], they will be listless, lethargic, or cry nonstop in the beginning,” she said. “They may have moments in which they stop breathing, change color, or look limp. However, they do not need to have all these symptoms together, one symptom alone is enough cause for investigation.”

Don’t worry too much

The Centers for Disease Control and Prevention (CDC) advises parents to follow the recommended for their infants.

They say doing so will protect babies from 14 .

“The schedule is designed to protect children when they are at highest risk of bad outcomes from the pathogens, also taking into account when they are likely to be exposed, how the diseases are transmitted, and how well the vaccines work at different ages,” Blumberg said. “Sticking to the recommended schedule protects children on time, when they need the protection, and when the vaccines are most likely to provide effective protection.”

Although newborns can be vulnerable to serious illnesses, Blumberg emphasized that the odds of a newborn infant contracting meningitis are low.

“It’s a scary world out there, no doubt about it. But this case, this story also needs to be put into perspective. In industrialized countries, the risk of getting meningitis is less than 1 in 1,000 newborns,” he said.

Even so, Nielsen said parents should not hesitate to contact their pediatrician if they have questions or concerns, even if it may seem trivial or unimportant.

“Babies are resilient, and the vast majority fare very well. However, they are still vulnerable in the first months of life, and we should exert common sense in minimizing exposures that can be dangerous to them,” she said.