When the government of Samoa sent out a call for volunteer doctors and nurses to aid in its vaccination campaign, pediatrician Vija Sehgal didn’t hesitate.

The call went out on a Monday. Early Wednesday morning, Dr. Sehgal, the director of pediatric services at Waianae Coast Comprehensive Health Center, was on a plane from Hawaii to Samoa.

With her, she hand-carried a Direct Relief Hurricane Preparedness Pack, which contained antibiotics, sterile water, and Pedialyte, among many other supplies.

She was one of more than 70 volunteers, she said, primarily pediatricians and registered nurses, who heeded Samoa’s call. “Our goal…was really to assist with this mass vaccination campaign,” she said.

Samoa is in the throes of a measles epidemic that has thus far infected 2% of the country’s population. The death toll has risen to 70, and most of those deaths have been young children.

The Samoan government announced last week that it was shutting down government offices and public services for two days to divert all attention – and its public servants – to a door-to-door vaccination campaign aimed at immunizing anyone from 6 months to 60 years old.

By mid-morning on Wednesday, Dr. Sehgal was heading one of more than 100 teams whose job it was to travel from village to village, looking for red flags, often made from T-shirts or scarves, outside of buildings – a sign that there were people inside who needed vaccinations.

Although the teams were made up of government employees from all walks of life – Dr. Sehgal chuckled when she recalled that there was an information technology specialist on her team – vaccines were administered by a doctor or registered nurse.

“There’s still a fair amount of mistrust,” Dr. Sehgal said. When the measles epidemic broke out, vaccination rates in Samoa were startlingly low – 31%, compared to about 69% worldwide.

The mistrust is thought to stem from an episode last year: Two infants died after receiving the measles vaccine, improperly mixed with an expired muscle relaxant instead of water. Although efforts have been made to educate the public about the mistake, vaccine hesitancy remains high.

However, when the team’s van pulled up to a red-flagged building, Dr. Sehgal said, people were so eager that they’d come running out to meet them. Like any experienced pediatrician, she traveled with stickers for the children she immunized.

“People were very willing to be vaccinated. In fact, we had to turn down a couple of people who were older than 60,” she recalled. “Quite a few of the people we vaccinated were very grateful that we came to them. They were afraid to go to the hospital to be vaccinated.”

People with confirmed cases of measles are being treated at local hospitals, they are being kept separate from the rest of the population. Nonetheless, Dr. Sehgal said, the people she encountered were afraid of potentially being exposed to measles.

There were some challenges. The measles vaccine has to travel under cold-chain conditions – repeatedly checked to make sure that it is staying within a narrow temperature range – in order to be safe and effective.

“It was hot and humid in Samoa,” Dr. Sehgal recalled. “We were working very quickly to…administer the vaccine without breaking the cold chain.”

At the end of the first day, they had a terrible surprise. They visited a house where two children needed vaccinations and then were told there was another, ill child.

“There was a 15-month-old female who had never been vaccinated because of the fears,” Dr. Sehgal said. The baby had been sick with measles for several days, had a fever, and was dehydrated.

“We immediately put her in our van…We drove as fast as we could, it was about a 45-minute drive.”

Dr. Sehgal said she was impressed by her team members, who intently hunted out every red flag they could find. And she was impressed by the Samoan government’s well-organized response – and their willingness to ask for volunteers.

“Samoa is a very proud country. I’m grateful that they asked for help, and I’m grateful there was such an outpouring of help on such short notice,” she said.

And as a doctor, she was delighted by the “hundreds” of people – many with smiling faces – that she was able to vaccinate. “It’s just wonderful to feel that you are welcomed, that you are wanted.”