As the Vancouver measles outbreak grows to 35 cases, doctors and public health officials continue to urge people to get vaccinated.

But what about infants? Immunizations generally don’t start until a baby turns one year old, potentially leaving them vulnerable to an infection. We spoke with an expert on child infections at Oregon Health and Science University to get the answers.

Doctor Dawn Nolt’s advice boils down to a few key points:

Make sure family and friends are vaccinated;

Stay away from unvaccinated people;

Stay away from areas that may have been exposed to the measles virus;

Breastfeed to pass on the mother’s antibodies to the infant.

Let’s break that down.

The ultimate protection for babies is everyone around them being vaccinated. The logic is simple: If babies aren’t exposed to someone who can get sick, then they’re unlikely to get sick themselves.

For parents, that means asking friends and family if they’re vaccinated, and urging those who aren’t to get it done. Nolt suggested avoiding those who turn down the advice.

It’s also important to stay away from places that could’ve been exposed to measles, such as the many locations listed by Clark County Public Health in the wake of the current outbreak. The virus can stick around for up to two hours after someone coughs or sneezes, and is highly contagious.

There is some good news for babies, because if their mother is vaccinated, they are born with some of her defenses against measles, Nolt said.

Humans develop antibodies in response to specific viruses, which then defend the body from future infections. A baby carries its mother’s antibodies for about six months after birth, and gets more through breast milk, Nolt said.

But that’s not to say the antibodies offer full protection. The antibodies start to leave a baby’s body starting around six months. Whatever a baby’s age, parents should take their infant to a doctor if they’ve been exposed to measles.

The antibodies happen to be the reason babies don’t usually get vaccinated until they’re one year old. The antibodies fight off the vaccine because they’re designed to fight off viruses that look like measles. That means that while a vaccine is harmless for an infant, the baby will have to get another one once the mother’s antibodies leave the body.

Do you know how the outbreak started? Get in touch.

-- Fedor Zarkhin

fzarkhin@oregonian.com

desk: 503-294-7674|cell: 971-373-2905|@fedorzarkhin

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