Needham (United States) (AFP) – US hospitals, clinics and pharmacies began vaccinating the nation’s youngest children against Covid-19 on Tuesday, a milestone that was welcomed by parents eager to protect kids from the worst impacts of the virus. Rollout of millions of shots was underway across the country, 18 months after the elderly became the first group eligible for immunization. Children aged from six months through four years aren’t at as great a risk as adults. But the sheer level of infections has seen more than 45,000 hospitalizations and nearly 500 deaths in the 0-4 group in Americ…