People ‘in their 20s, 30s and 40s’ becoming key spreaders of COVID-19, experts say

People in their 20s, 30s and 40s are becoming key spreaders of COVID-19, according to several studies, health experts and World Health Organization officials.

Takeshi Kasai, the WHO’s Western Pacific regional director, said during a virtual press conference also held on Aug. 18 that younger people have been “increasingly driving the spread” of COVID-19.

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“People in their 20s, 30s and 40s are increasingly driving the spread,” Kasai said. “The epidemic is changing.”

Kasai said it’s important for everyone, regardless of age, to continue to follow social distancing guidelines and practice “behaviors that protect their health and that of their family members, colleagues and community.”

“Many are unaware they’re infected—with very mild symptoms or none at all,” Kasai continued. “This can result in them unknowingly passing on the virus to others. This increases the risk of spillovers to the most vulnerable: the elderly, the sick, people in long-term care, people who live in densely-populated urban areas and under-served rural areas. We must redouble efforts to stop the virus from moving into vulnerable communities.”

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Ongoing data collected by the Centers for Disease Control and Prevention showed that a bulk of positive COVID-19 cases ranged between the ages of 18-64.

A study conducted in Japan in September showcased data collected from 3,184 COVID-19 positive patients and contact tracing revealed that 50 percent of patients who were the main vectors for spreading the virus were between the ages of 20–39 years. The study also revealed that of that 50 percent, 41 percent were asymptomatic.

In the United States, small communities such as Shelby County, Tennessee have seen a large portion of their positive COVID-19 cases within the 18-40 age range, according to the state health department’s dashboard.

In a June 25 CDC telebriefing update on COVID-19, CDC Director Robert Redfield mentioned the trend as cases saw a surge during the summer,

“As you know, in Florida, a significant number of the infections, and actually in the Southeast and Southwest, are in individuals now that are younger than the age of 50,” Redfield said.

Redfield also mentioned that while the CDC continues surveillance throughout the U.S. to ensure the number of cases is accurate, diagnostics in young people were not as “aggressively” pursued as those who were at higher risk, for example, patients who are 65 and older.

“But I will say, I remain concerned about trying to understand the effective public health messaging that we need to get to those individuals that are say under the age of 45, under the age of 30, whereas the impact and consequences of COVID-19 infection on them may not be highly associated with hospitalization and death. They do act as a transmission connector for individuals that could, in fact, be at higher risk,” Redfield said.

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Dr. Brian Garibaldi, director of the Johns Hopkins Biocontainment Unit and associate professor of medicine, said that the demographics of the pandemic are indeed changing.

“This initially started off with a much older population,” Garibaldi said. “And we saw patients who had multiple co-morbidities, who are older, often times nursing home patients, were getting very sick and unfortunately, in many cases, dying from COVID.”

“Over time, we’ve seen some demographic shifts, away from that nursing home population,” Garibaldi continued. “We’ve seen a large number of cases in the Latinx community, the African American community, and we’ve also started to see a shift in age groups who are getting infected with COVID.”

Garibaldi confirmed that the increase in infection rates has been in patients between the ages of 20-40.

As restrictions start to lift in many states in the U.S., Garibaldi believes the reason in the spike of younger people becoming infected with COVID-19 is due in part to the kind of lifestyles they typically lead. Apart from going out to eat, enjoying nightlife or just going out in general, Garibaldi also believes a contributing factor to the higher infection rate is that many of the people in the younger age group are unable to work from home or are unable to properly social distance at their jobs.

“I think there also, probably, is some component of that age group that is also out and about working,” Garibaldi said. “For whatever reason, may not be able to socially distance or work in jobs where they are not able to work from home and have to commute and have to be in situations where we know the risk of spread is higher.”

College students returning to campus could also see a potential spike in infection rates among an adjacent age group, according to Garibaldi.

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“We have yet to see, I think reflected in the national numbers, the return to college, which is also likely going to lead to an increase in cases among that younger age group,” Garibaldi posited. “We have seen pockets of outbreaks in schools that have returned in August and I think we are all anxious to see what will happen as other universities and other areas return.”

Another trend Garibaldi believes will become more of an issue as the pandemic continues are cases among younger children.

“We’re worried about what happens when schools go back among that younger age group,” Garibaldi said. “There was a sort of lag in terms of the number of cases we saw among the pediatric population, and now we’re starting to see that, that’s actually a very high group in terms of the number of cases we are seeing.”

And Garibaldi believes a lack of encouragement for widespread testing for all age groups, including asymptomatic people or children, is part of why data now reflects increased infections and hospitalizations within the 20-40 age range.

“Part of that may reflect testing,” Garibaldi continued. “Part of that may reflect the fact that early on in the outbreak, children by and large were staying at home and those adults who were going out and having to work. So, I think there’s a lot of uncertainty about what’s going to happen when schools go back in certain areas in the fall.”

Garibaldi, like other health experts, also expressed concern about the new guidelines set by the CDC for testing.

“I’m very concerned about the change in recommendations about testing,” Garibaldi said. “I think the only way we’re going to get out in front of this virus is if we understand where the hot spots are, and if we are careful about focusing our mitigation efforts on those areas. The whole principle around contact tracing is being able to widely test contacts of known of suspected cases and if we discourage people from getting tested or change those guidelines, there’s no way we’re ever going to get out in front of this virus.”

Garibaldi cautioned younger people to not misconstrue their relative health for immortality.

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“We have to be careful with this assumption that just because you’re younger, that you’re not going to get sick,” Garibaldi stressed. “We’ve taken care of a number of individuals in our intensive care unit who were under the age of 40, under the age of 30, who have become severely ill, and required advanced life support and in some cases, have died.”

While those with co-mobidities or who are advanced in age have a higher chance of dying from COVID-19, Garibaldi said those are not the only factors that lead to death.

Common conditions such as obesity contribute to a higher mortality rate when it comes to COVID-19, according to Garibaldi.

“We know that obesity is a huge risk factor and unfortunately our population has one of the highest incidences of obesity in younger-aged adults in the world, so this notion that I’m young, I’m going to be fine, is not true,” Garibaldi said.

And while Garibaldi is hopeful that the upcoming flu season will actually be attenuated due to the country’s mindfulness over spreading COVID-19, he believes health care systems will be stressed once again as patients come in not knowing whether they’ve contracted the flu or the novel coronavirus.

“It’s obviously bigger than you. Your behavior impacts those around you, but this disease is no joke. I’ve seen young, healthy people who are in the best shape of their lives, end up in an ICU and die from this virus and to think that it can’t happen to you because you’re young is foolish and it’s also selfish,” Garibaldi stressed.

As waves of schools and businesses around the country are cleared to reopen, college towns are moving toward renewed shutdowns because of too many parties and too many COVID-19 infections among students.

With more than 300 students at the University of Missouri testing positive for the coronavirus and an alarming 44% positivity rate for the surrounding county, Stephanie Browning, director of Columbia/Boone County Public Health and Human Services said Friday ordered bars to stop serving alcohol at 9 p.m. and close by 10 p.m.

“What we’re seeing in our violations is they’re coming late at night,” said Browning. “Big groups gathering. They’re not wearing their masks, they’re not social distancing.”

The Associated Press contributed to this report.