Switzerland's infectious disease chief says children under age 10 can hug their grandparents. Not all experts agree.

• Daniel Koch, the infectious diseases chief of Switzerland, announced that healthy children under the age of 10 can give their grandparents brief hugs.
• Most countries in the world are using lockdown guidelines that recommend children do not hug their elderly grandparents, out of concern that the children may infect elders with the virus.
• World Health Organization technical lead Maria van Kerkhove and German virologist Christian Drosten publicly disagreed with Koch, saying that researchers don't know enough about the disease to assume children aren't at risk of spreading it.
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For children around the world, video calls have been the main way they communicate with grandparents while quarantined. But children in Switzerland under the age of 10 have been given the green light to hug their grandparents, according to new recommendation from Daniel Koch, the country's infectious disease chief.

"Young children are not infected and do not transmit the virus," Koch said in a press conference. "They just don't have the receptors to catch the disease." He said brief hugs are safe and could benefit seniors' mental health.

Most countries in the world have enforced lockdown rules that do not advise children to have contact with their elderly grandparents, but Switzerland has bucked the trend.

This new revision of the current guidelines comes after consultation with Swiss university experts, according to broadcaster SRF, and only applies to healthy children under age 10.

Babysitting is still not allowed, and contact should be kept short, Koch said.

"Children are most certainly not the drivers of this epidemic," Koch said earlier in April. In Switzerland, people under 20 accounted for around 3% of all COVID-19 cases.

Switzerland is one of a few European countries beginning to loosen lockdown measures, taking the first step in a three-stage plan to reopen the country by allowing barbershops, tattooists, and garden stores to accept customers. Swiss public schools will open on May 11, while libraries and museums will reopen on June 8.

Many scientists disagree with Koch's decision

German virologist Christian Drosten, who was one of the first to develop a WHO-approved coronavirus test, has publicly disagreed with Koch. He told Austrian broadcaster ORF that caution should be exercised when looking at studies which show that children are less affected by the virus. Far too little research has been done, he said, and the results that exist are contradictory.

Drosten pointed out that the findings of a Dutch study, which was used as evidence that children do not play a big role in spreading COVID-19, were not statistically significant.

In the US, where people under 18 accounted for 1.7% of all COVID-19 cases, health experts are still advising that young children keep a distance from the elderly.

"I'm sure many grandparents around the world are dying to hug their grandchildren," Maria van Kerkhove, a World Health Organization technical lead, said during a WHO press conference on April 29. "There's no reason to think that children are less susceptible to infection if they're exposed, and that they can't transmit. We're really not seeing this in the epidemiology."

One recent study published in The Lancet, examining COVID-19 cases in Shenzhen, China, concluded that "children are at a similar risk of infection to the general population, although less likely to have severe symptoms; hence they should be considered in analyses of transmission and control."