Chile overcame the Delta variant. Now it's racing to vaccinate kids

Chile has become one of the few countries in the world to approve vaccination for children as young as 6.

(CNN)Liliana Silva didn´t see it coming. When her brother traveled from Germany, where he lives, to visit his family in Chile, none of them felt vulnerable. He had completed the 10-day mandatory quarantine in Santiago and shown no symptoms of Covid-19.

Yet, less than a week later, her parents, her three daughters and an aunt were infected with the Delta variant. She and her husband weren´t spared. Soon, they also felt unwell. Nearly everyone had mild symptoms, lasting from 2 to 4 days -- except for her father and children.
    "My father suffers from chronic leukemia; he had pneumonia, got dehydrated and was hospitalized. If he hadn't gotten his shots, he would have died," she said, referring to the Covid-19 vaccine.
      Her children, however, were too young to have been vaccinated, and suffered badly from the infection. "My daughters went through high fever, coughing, vomiting and bad headaches. I wish they had been vaccinated; I was in constant fear for them," she said.
      Since Chile started immunizing its population against Covid-19, last February, it has been internationally praised for its smooth and successful vaccination campaign. According to the health ministry's latest reports, almost 87% of eligible Chileans are fully vaccinated.
      That's a figure that positions this South American country among the nations with the highest share of people immunized. Chile also stands out compared to the rest of Latin America and the Caribbean, where 75% of the regional total population had yet to be fully vaccinated as of Sept 1, according to the Pan American Health Organization.
        The high immunization coverage has led to decreasing infection rates, but Chile doesn't plan to cut back precautions, or ease its vaccination drive. Last week, the government announced that Chile would become one of the few countries in the world to approve vaccination with CoronaVac for children between the ages of 6 and 11. Inoculations started on Monday.
        "It is known that in countries where most of the adult population has been immunized, the coronavirus starts targeting those who remain more vulnerable and kids get more infected, as is happening in the United States," says Dr. Lorena Tapia, a pediatrician and infectologist from the Universidad de Chile and a member of the advising committee on vaccines for the Science Ministry.
        "We must move forward with immunization among the youngest."

        An early strategy

        Different elements explain Chile´s successful vaccination rate. Authorities started planning a response to the pandemic very early on. In May 2020, two months after the country reported its first Covid cases, the Ministry of Science began negotiating contracts with different labs -- Pfizer, AstraZeneca, Sinovac (which makes the Coronavac), and CanSino -- to secure the purchase of shots for all Chileans.
        Simultaneously, the institution worked on having the local scientific community take part in Phase 3 clinical trials, which would give the country priority in the supply of vaccines. Ultimately, commercial deals were closed promptly.
        "From the beginning, our campaign was based on the advantages of having a diversified portfolio of vaccines," says Minister of Science Andrés Couve.
        "That allowed us not to depend on the availability of one provider only, considering the high demand there is for anti-Covid doses globally," he adds.
        That strategy, combined with an overall historically well-organized vaccination system, the setting up of 1400 new inoculation sites and an easy-to-access scheduling system by eligible groups, has allowed the country's vaccination process to move forward with few interruptions.
        It helps that Chile has a small population. And its relatively low debt and long-time responsible fiscal policy also mean enough funds to buy sufficient vaccines. The country's political and economic stability has even attracted Chinese investments: Sinovac recently announced it will open a vaccine factory near Santiago next year.
        So far Chile has received 36 million doses for a population of 19 million, enough to have already started distributing booster shots. Every week, a new group of people become eligible for the boosters -- this week, the country is giving booster shots to people ages 55 and up.
        "It's very easy to get vaccinated in Chile and people have been very responsible. The anti-vaccine movement is marginal," says Eduardo Undurraga, a former researcher at the US CDC and current professor at Universidad Católica de Chile.
        Chileans have historically relied on immunization campaigns, and vaccine skepticism has not taken deep root in the country. In fact, Chile eradicated smallpox 27 years earlier than the rest of the world and was the third country to control polio. Citizens' trust in vaccines has also allowed to significantly reduce childhood diseases such as measles, mumps, and rubella.
        Undurraga was part of the team leading an evaluation of the effectiveness of the CoronaVac inactivated SARS-CoV-2 vaccine, using a massive prospective cohort of approximately 10 million individuals in Chile. The study was commissioned by the country's health ministry after the international community raised doubts about the efficacy of maker Sinovac's formula, which has been the backbone of Chile's immunization campaign.
        The results, released in early July, were reassuring: the study found that its effectiveness was about 66% for prevention