https://www.cidrap.umn.edu/covid-19...y-parties-spread-covid-19-grandparents-during
Contagious cuteness: Children’s birthday parties spread COVID-19 to grandparents during pandemic
Liz Szabo, MA
Today at 4:07 p.m.
COVID-19
Pneumonia
Influenza, General
Their chubby cheeks. Their dimpled knees. Their sticky, unwashed hands and perpetually runny noses. Their tendency to put absolutely everything they can grab into their mouths.
Anyone who has lived with a toddler or preschooler knows that youngsters are avid collectors of germs. And they can’t help sharing them.
During the pandemic, a new study suggests, many older adults were infected with COVID-19 around the time of their grandchildren’s birthdays, probably during parties or family gatherings.
In a study of more than 1.1 million older Danish adults, researchers found that grandparents were 10% more likely to test positive for the coronavirus in the week after a grandchild’s birthday than during other times.
The study included almost 1 million grandchildren, whose medical records were linked to those of their grandparents. The study was made possible because of Denmark’s comprehensive national healthcare system, which records every medical or pharmacy visit, as well as the country’s population registry. ‘
Absolutely fascinating’ results
“You couldn't do this study anywhere except in Denmark,” said William Schaffner, MD, a professor of preventive medicine and infectious diseases at Vanderbilt University School of Medicine, who wasn’t involved in the new study. “It's absolutely fascinating."
A grandparent’s risk of infection was greater if the child celebrating a birthday was in preschool than if the grandchild was older. Grandparents were also at higher risk of developing COVID-19 if they were older than 67, the study showed.
You couldn't do this study anywhere except in Denmark.
Older people tend to have weaker immune systems than younger adults, Schaffner said. Older adults are also more likely than younger people to have chronic diseases that put them at higher risk of being severely ill with COVID-19.
“If you think of grandparents and grandchildren, there's a lot of hugging and kissing and sitting in the lap,” Schaffner told CIDRAP News.
A confetti-covered petri dish
Like other respiratory diseases, COVID-19 spreads best in crowded environments where people are in close contact, especially indoors, said Jennifer Shu, MD, an Atlanta pediatrician not involved in the new study.
Although most children infected with COVID-19 during the pandemic do not become seriously ill, youngsters were a significant source of infection within households during the pandemic, especially when school was in session, according to a 2023 study.
Children at a party can transmit COVID-19 even if they appear healthy, Shu notes. Youngsters under age 4 years are more likely to have asymptomatic COVID-19 infections than adults, even when their noses are full of viruses.
Studies have long shown that children are adept at spreading germs, from colds and flus to pneumococcal disease, which can cause everything from ear aches to pneumonia. A 2024 study found that the biggest risk factor for pneumococcal infection in older adults was contact with children.
Pneumococcal infections in older adults often spike during the holidays, possibly because people are infected at family gatherings. In a bit of good news, though, the release of a pneumococcal vaccine for children has broken that pattern, protecting both kids and their grandparents.
Naive immune systems
Research shows that adults who live with children are more likely to develop a respiratory illness.
But children’s underdeveloped handwashing and nose-blowing skills aren’t the only reason.
Babies and children have immature immune systems in the first few years of life, Schaffner said. That leaves them vulnerable to germs they encounter at daycare and preschool, he said.
Scientists have especially robust data on how children react to the flu.
“When they get those first infections, the virus really multiplies abundantly,” Schaffner said. With flu, “children shed more virus for longer periods of time than do adults. And so that really makes them excellent transmitters, in addition to the fact that they're not very hygienic.”
Parents won’t be surprised to learn that research shows toddlers and pre-school-aged children can have eight to 12 colds, other respiratory infections, or stomach bugs a year. Meanwhile, school-age children and preteens average five or six illnesses annually. In comparison, teens and adults develop two to three colds or other infectious illnesses per year, according to Rady Children’s Health.
Don’t blame kids for the pandemic
But that doesn’t mean that kids were responsible for the COVID-19 pandemic.
“In general, children were not major drivers of spread, the way they are for other respiratory viruses,” said Amesh Adalja, MD, a senior scholar at the Johns Hopkins Center for Health Security.
Adalja notes that adults, including parents’ friends and neighbors, often attend children’s birthday parties, too, especially when babies and toddlers are too young to have their own close friends.
When they get those first infections, the virus really multiplies abundantly.
The new study analyzed COVID-10 infections from February 19, 2020, to February 28, 2022. During that time, 27.5% of grandparents tested positive for the coronavirus.
Grandparents in the study ranged from 60 to 73 years old, with a median age of 67. More than 54% of grandparents were women, and 58% had one or two grandchildren.
Schaffner notes that researchers had no information about whether grandparents actually attended any parties. Study authors simply assumed that a family gathering had taken place around the time of a grandchild’s birthday.
“If you read the methods section for the study carefully, these authors haven't been to a single birthday party,” Schaffner said. “They don’t even know for sure.”
Nevertheless, Schaffner said the study authors are “undoubtedly correct,” given the size of the Danish database and social customs in that country.
One bright spot in the study: Celebrating a birthday with a grandchild did not increase an older adult’s risk of death.
Contagious cuteness: Children’s birthday parties spread COVID-19 to grandparents during pandemic
Liz Szabo, MA
Today at 4:07 p.m.
COVID-19
Pneumonia
Influenza, General
Without a doubt, young children are the world's most adorable vectors of disease.Their chubby cheeks. Their dimpled knees. Their sticky, unwashed hands and perpetually runny noses. Their tendency to put absolutely everything they can grab into their mouths.
Anyone who has lived with a toddler or preschooler knows that youngsters are avid collectors of germs. And they can’t help sharing them.
During the pandemic, a new study suggests, many older adults were infected with COVID-19 around the time of their grandchildren’s birthdays, probably during parties or family gatherings.
In a study of more than 1.1 million older Danish adults, researchers found that grandparents were 10% more likely to test positive for the coronavirus in the week after a grandchild’s birthday than during other times.
The study included almost 1 million grandchildren, whose medical records were linked to those of their grandparents. The study was made possible because of Denmark’s comprehensive national healthcare system, which records every medical or pharmacy visit, as well as the country’s population registry. ‘
Absolutely fascinating’ results
“You couldn't do this study anywhere except in Denmark,” said William Schaffner, MD, a professor of preventive medicine and infectious diseases at Vanderbilt University School of Medicine, who wasn’t involved in the new study. “It's absolutely fascinating."
A grandparent’s risk of infection was greater if the child celebrating a birthday was in preschool than if the grandchild was older. Grandparents were also at higher risk of developing COVID-19 if they were older than 67, the study showed.
You couldn't do this study anywhere except in Denmark.
Older people tend to have weaker immune systems than younger adults, Schaffner said. Older adults are also more likely than younger people to have chronic diseases that put them at higher risk of being severely ill with COVID-19.
“If you think of grandparents and grandchildren, there's a lot of hugging and kissing and sitting in the lap,” Schaffner told CIDRAP News.
A confetti-covered petri dish
Like other respiratory diseases, COVID-19 spreads best in crowded environments where people are in close contact, especially indoors, said Jennifer Shu, MD, an Atlanta pediatrician not involved in the new study.
Although most children infected with COVID-19 during the pandemic do not become seriously ill, youngsters were a significant source of infection within households during the pandemic, especially when school was in session, according to a 2023 study.
Children at a party can transmit COVID-19 even if they appear healthy, Shu notes. Youngsters under age 4 years are more likely to have asymptomatic COVID-19 infections than adults, even when their noses are full of viruses.
Studies have long shown that children are adept at spreading germs, from colds and flus to pneumococcal disease, which can cause everything from ear aches to pneumonia. A 2024 study found that the biggest risk factor for pneumococcal infection in older adults was contact with children.
Pneumococcal infections in older adults often spike during the holidays, possibly because people are infected at family gatherings. In a bit of good news, though, the release of a pneumococcal vaccine for children has broken that pattern, protecting both kids and their grandparents.
Naive immune systems
Research shows that adults who live with children are more likely to develop a respiratory illness.
But children’s underdeveloped handwashing and nose-blowing skills aren’t the only reason.
Babies and children have immature immune systems in the first few years of life, Schaffner said. That leaves them vulnerable to germs they encounter at daycare and preschool, he said.
Scientists have especially robust data on how children react to the flu.
“When they get those first infections, the virus really multiplies abundantly,” Schaffner said. With flu, “children shed more virus for longer periods of time than do adults. And so that really makes them excellent transmitters, in addition to the fact that they're not very hygienic.”
Parents won’t be surprised to learn that research shows toddlers and pre-school-aged children can have eight to 12 colds, other respiratory infections, or stomach bugs a year. Meanwhile, school-age children and preteens average five or six illnesses annually. In comparison, teens and adults develop two to three colds or other infectious illnesses per year, according to Rady Children’s Health.
Don’t blame kids for the pandemic
But that doesn’t mean that kids were responsible for the COVID-19 pandemic.
“In general, children were not major drivers of spread, the way they are for other respiratory viruses,” said Amesh Adalja, MD, a senior scholar at the Johns Hopkins Center for Health Security.
Adalja notes that adults, including parents’ friends and neighbors, often attend children’s birthday parties, too, especially when babies and toddlers are too young to have their own close friends.
When they get those first infections, the virus really multiplies abundantly.
The new study analyzed COVID-10 infections from February 19, 2020, to February 28, 2022. During that time, 27.5% of grandparents tested positive for the coronavirus.
Grandparents in the study ranged from 60 to 73 years old, with a median age of 67. More than 54% of grandparents were women, and 58% had one or two grandchildren.
Schaffner notes that researchers had no information about whether grandparents actually attended any parties. Study authors simply assumed that a family gathering had taken place around the time of a grandchild’s birthday.
“If you read the methods section for the study carefully, these authors haven't been to a single birthday party,” Schaffner said. “They don’t even know for sure.”
Nevertheless, Schaffner said the study authors are “undoubtedly correct,” given the size of the Danish database and social customs in that country.
One bright spot in the study: Celebrating a birthday with a grandchild did not increase an older adult’s risk of death.