The top US health body has issued new guidelines on the reopening of schools, clearly weighting its recommendations in favor of returning students to their classes in fall.

Photo: AFP

The updated advice from the Centers for Disease Control and Prevention (CDC) was posted Thursday night, and came a few weeks after it was asked to change course by President Donald Trump.

"Being at the school, being on the campus, is very, very important," President Donald Trump told White House reporters Thursday.

With the virus still rampant in many parts of the country, a number of cities including Houston and Los Angeles have already announced that schools will reopen virtually.

Others like New York, where the epidemic has receded, are opting for a hybrid model.

The CDC's earlier guidelines had emphasized extreme caution, but the agency was asked by Trump earlier this month to revisit the topic. 

The new advice reads: "Schools are an important part of the infrastructure of communities and play a critical role in supporting the whole child, not just their academic achievement."

But the agency maintains that it is not wise to re-open if the virus is circulating locally, and continues to urge physical distancing and use of masks. 

The scientific community's position on schools has been evolving.

The risk of children becoming seriously ill from COVID-19 is very low, while pediatricians emphasize the beneficial role schools play in children's social development and mental health.

According to the CDC, prolonged school closures could worsen achievement gaps across income levels and racial and ethnic groups.

A study of 800,000 students by researchers at Brown and Harvard looking at how an online math program called Zearn was used found that student progress decreased throughout late April, particularly in low-income areas.

There are other benefits -- such as identifying cases of child abuse. 

The capital Washington saw a 62 percent decrease in child abuse reporting calls compared to last year, but more severe cases of child abuse were presented in emergency rooms.

The CDC concluded: "The best available evidence from countries that have opened schools indicates that COVID-19 poses low risks to school-aged children, at least in areas with low community transmission, and suggests that children are unlikely to be major drivers of the spread of the virus."