What does it mean for a pandemic like Covid to become “endemic”?

For months American When European The leaders have a coronavirus Pandemic Will be soon Endemic.. Covid-19 solves the illnesses we learn to live with.according to Several GovernorAlmost there.

But we still Acute phase Pandemic, and what Endemic Covid It may look like a mystery. There are many forms of endemic disease, but it is not yet known where this 2-year-old illness applies.

The most basic endemic is Constant, predictable or expected presence.. It is a persistent illness. Beyond that, there is no fixed definition.

Endemic infects millions of people around the world each year, and some endemic kill hundreds of thousands. Some can be treated or vaccinated. However, they can also cause unexpected outbreaks and serious distress.

Interviews with 20 scientists, public health experts, and medical historians suggest that endemic may be missing out on the point and is in a hurry to recast Covid. ..

Lukas Engelmann, a historian of medicine and epidemiology at the University of Edinburgh, said: However, he said epidemiologists are using endemic to mean that we have to look carefully because endemic can be epidemic again.

Endemic can be mild or fatal

When people think of endemic, they often think of the common cold. Upper respiratory tract infectionIt is estimated to infect billions of people worldwide each year, including colds, but thousands die. Other endemic diseases can be much more deadly. malaria In 2019, more than 600,000 people died worldwide and influenza killed more than 200,000, but it is estimated that these tolls could be much higher.

Many scientists predict that endemic Covid can bear the same burden as other respiratory viruses.

Lone Simonsen, director of the PandemiX Center at the University of Roskilde in Denmark, said:

“The reason for this is that we have a lot of immunity and we continue to be boosted by the infections we encounter,” she said.

Some scientists warn that immune protection from vaccination and infection can diminish over time, and future variants may evade their defenses.And mutation RandomTherefore, there is always the possibility that mutants that cause more serious illness will occur in the future.

Endemic can reach an epidemic

Colds and flu are endemic diseases that last all year round, but their levels are not constant.Instead they cause the seasons EpidemicIf the infection rises above the baseline Endemic Levels, often in winter when people gather indoors.

These patterns are predictable, but people can change them: the control measures used to blunt the Covid pandemic. Moistened Influenza and cold waves in recent years.

Scientists say that endemic Covid can be seasonal, but it can also lead to irregular and significant epidemic waves.

Jeffrey Shaman, an infectious disease modeler at Columbia University, said: “Only a small part of the population needs to be susceptible to outbreaks, which can happen at any time of the year.”

The burden of endemic is unequal

The experience of one community with endemic disease can be very different from that of another. It often depends on who is ill and whether testing, treatment and healthcare are available.

Scientists and public health workers use both “epidemic” and “endemic” to describe the virus, including HIV, which has been around the world for over 40 years.

“One of the definitions of endemic is defined by geographic location,” said Dr. Diane Havlir, an infectious disease specialist and professor of medicine at the University of California, San Francisco. “Through that lens, HIV is endemic in the United States, with about 1.2 million people living with HIV.”

“But HIV is prevalent in the US subpopulation,” she added.

Infectious diseases often remain in communities where poverty and discriminatory systems impede access to health care, Dr. Havlir said.

“Unless you deal with it first, the illness gap grows over time,” she said. “And that raises the question: are we dealing with those disparities in Covid, or are we on the same track?”

According to experts, part of the world is endemic because one-third of the world’s population is not vaccinated against Covid and life-saving treatments are not available to everyone. Even if you decide, the burden of the virus will continue to be unequal.

Endemic is all about control

Of the many forms of endemic disease, one thing is clear: endemic disease does not mean the end of the disease.

Instead, it means living with the illness, and often managing it. Punched.. Health experts say the country must use control measures such as testing, treatment and vaccination to control endemic disease.

A country where malaria is endemic Aim for eradication It is a mosquito-borne disease and relies on interventions such as pesticides and prophylactic treatment to reduce its incidence. These controls, like South Africa, can dramatically change the course of endemic malaria.

In addition to environmental management, vaccination programs can reduce cases and deaths.But if the community does not comply Vaccination recommendationsOccurrence may occur.

For example, measles continued to be prevalent in the United States for 40 years after the introduction of the vaccine. During that period, unvaccinated people remained vulnerable and occasionally contributed to the outbreak.2019, 20 years after the illness was declared Exclusion In the United States, several outbreaks associated with unvaccinated travelers have infected more than 1,000 people.

Unlike malaria and measles, public health experts are Covid Can’t eradicationTherefore, control measures help determine the size and course of future waves. (We have eradicated only one human disease, smallpox. Smallpox behaved quite differently from Covid.)

Keeping up with Covid means staying focused on vaccination, treatment and renewal of vaccines, said Dr. Monica Gandhi, an infectious disease specialist and professor of medicine at the University of California, San Francisco. “It takes constant vigilance to maintain it-not to eradicate it, but to keep it under control-but that’s what humans want.”

When do you know what the endemic stage of Covid looks like?

Probably not for a while. Scientists usually observe the disease for many years and then determine the endemic pattern of the disease.

Pandemic can be taken Year to settleAnd that The consequences of widespread illness may continue Long after the new infection disappeared.

Much of what we know about the transition from a pandemic is due to the flu — humans have witnessed four flu pandemics in the last 100 years. The 1918-19 pandemic, which killed more than 50 million people worldwide, dwarfed them all.

It took three years for the 1918 influenza pandemic to settle into a more regular pattern. 1920 waves It killed more people in some cities than the previous wave had. In the years that followed, some seasonal outbreaks were greater than others.

The assumption about the Covid epidemic period is that it will look significantly different from the pandemic of the last two years. But in the worst-case scenario, endemic Covid can look like where we were.

“I can imagine an event like Omicron happening every year,” said Trevor Bedford, a virologist at the Fred Hutchinson Cancer Research Center in Seattle.

“It could be an endemic condition,” said Dr. Bedford. “And that doesn’t mean it’s calm, and it doesn’t mean it’s manageable.”