WASHINGTON - About 34,500 new COVID-19 child cases were reported in the United States last week, marking the lowest number of new weekly cases since early October last year, according to the latest report of the American Academy of Pediatrics (AAP) and the Children's Hospital Association.

Child cases represented 24.3 percent of the total new weekly cases of 141,848 in the week from May 20 to 27, according to the report.

Over the past two weeks, there was a 2 percent increase in the cumulated number of child COVID-19 cases, said the report.

As of May 27, nearly 4 million children in the United States had tested positive for COVID-19 since the onset of the pandemic, according to the report.

Child cases represented 14.1 percent of all COVID-19 cases. The overall rate was 5,285 cases per 100,000 children in the population, according to the report.

Children accounted for 1.3 percent to 3.2 percent of total reported hospitalizations, and 0 to 0.23 percent of all COVID-19 deaths, said the report.

"At this time, it appears that severe illness due to COVID-19 is rare among children. However, there is an urgent need to collect more data on longer-term impacts of the pandemic on children, including ways the virus may harm the long-term physical health of infected children, as well as its emotional and mental health effects," the AAP said in the report.

Weekly increase of child COVID-19 cases in the United States hit record high in mid January, which stood at over 211,000 cases, AAP data show.

Since mid April, weekly increase fell continuously from nearly 90,000 to about 34,500 cases.

On May 10, the US Food and Drug Administration authorized the emergency use of the Pfizer vaccine for adolescents aged 12 to 15.

Over 136 million people over 12 years of age in the United States have been fully vaccinated against COVID-19 as of Wednesday, accounting for 48.6 percent, according to data of the US Centers for Disease Control and Prevention.