On its 5th anniversary, experts address questions about COVID-19
In 5 years, COVID-19 has impacted nearly every aspect of life. Although tens of thousands of cases continue to occur each week, the world’s top public health agencies have considered the pandemic phase of COVID-19 to be over for years.
“The pandemic is over if you define pandemic as something that changes the way we live, work or play,” Paul A. Offit, MD, director of the Vaccine Education Center and attending physician in the division of infectious diseases at The Children’s Hospital of Philadelphia, told Healio. “We are back to normal, but the virus isn't over.”
According to WHO, more than 777 million cases of COVID-19 have been reported globally, including more than 7 million deaths, with 103 million cases and 1.2 million deaths being reported in the United States alone.
We checked in with Offit and other experts to answer five questions about COVID-19 and the virus that causes it 5 years after the pandemic began.
Where did SARS-CoV-2 originate?
In December 2019, Chinese health authorities began investigating a then-unidentified strain of pneumonia that had sickened dozens of people in Wuhan, located in the central part of the country.
On Jan. 7, 2020, authorities reported that 59 cases in the city had been confirmed in the previous 4 weeks and that many of the patients lived near the Huanan Seafood Wholesale Market.
Although testing of animals sold at the market before the outbreak was limited, researchers and investigators have found evidence of SARS-CoV-2 in environmental samples.
China’s CDC reported in early 2021 that the market was likely the epicenter of the outbreak and that at least one spillover to a human occurred there, a conclusion also reached by WHO, according to a study published in March 2021 that found the most likely introduction of the virus was through either zoonotic transmission through an intermediate host or direct zoonotic transmission. The report called it “extremely unlikely” that there was an accidental introduction of SARS-CoV-2 due to a lab accident at the nearby Wuhan Institute of Virology, but that scenario gained support from the CIA in a report released in January, according to multiple outlets.
In 2022, two studies published in Science provided more evidence that the pandemic originated in the market, not the lab. An analysis by Worobey and colleagues showed that most of the initial cases were linked to the market, and that SARS-CoV-2-positive environmental samples collected at the market were concentrated in an area where vendors were selling live mammals. In the other study, Pekar and colleagues documented evidence that two lineages of SARS-CoV-2 were present at the market early on, suggesting both lineages emerged and spread from there. The evidence “challenges the suggestion that the market was simply a superspreading event, which would be lineage specific,” the researchers wrote.
“The evidence is truly overwhelming that it was a natural event,” Gigi Gronvall, PhD, senior scholar at the Johns Hopkins Center for Health Security and professor of environmental health and engineering at the Johns Hopkins Bloomberg School of Public Health told Healio.
How are we tracking COVID-19?
For much of the pandemic, the CDC monitored and reported COVID-19 cases, hospitalizations and deaths.
“It gave us a pretty accurate picture of the incidence and prevalence of COVID cases and hospitalizations,” Lawrence O. Gostin, JD, co-faculty director of the O’Neill Institute for National and Global Health Law at Georgetown University, told Healio. “That enabled us to see when there were spikes in cases and/or hospitalizations.”
The data were used to inform the public about risks and influenced COVID-19-related policies, including school and business closures and mask recommendations.
That has changed. In May 2023, the CDC stopped reporting new cases when the public health and national emergencies for COVID-19 expired. And as of last year, hospitals are no longer required to report cases.
The CDC instead has been tracking the proportion of tests that are positive for SARS-CoV-2 and the proportion of ED visits that end up with a COVID-19 diagnosis as early indicators of spread. The rate of hospitalization and percentage of all U.S. deaths that are due to COVID-19 are indicators of severity, according to the CDC.
But a lot of COVID-19 tracking has shifted to wastewater surveillance, Gostin said. The method can be accurate for monitoring infectious diseases — even asymptomatic cases — according to the CDC.
“This enables us to have a fairly good idea of when cases are spiking,” Gostin said.
He added, though, that wastewater surveillance is not as accurate as reporting in terms of tracking cases, hospitalizations and deaths. Despite this, he does not foresee COVID-19 surveillance shifting back to mandated reporting.
“There is no appetite in the country to go back to case reporting, so I think we are doing all that we can,” Gostin said.
How are we treating it?
Patients with COVID-19 must start treatment within 5 to 7 days after they begin to experience symptoms, depending on the medication, the CDC notes.
On its website, the CDC features three COVID-19 treatment recommendations made by the Infectious Diseases Society of America:
- Paxlovid for ambulatory adults and children aged 12 years or older who are at high risk for severe disease, to be started as soon as possible within 5 days of symptom onset;
- molnupiravir for high-risk adults, to be started within 5 days of symptom onset; and
- remdesivir for adults and children at high risk for severe disease, to be given intravenously in a health care facility for 3 consecutive days, starting within 7 days of symptom onset.
The IDSA also has recommendations for treating hospitalized patients who are critically ill with COVID-19, which are available in a link at the end of the story.
Most of the IDSA’s recommendations supporting specific treatments are based on low certainly of evidence.
Peter Katona, MD, clinical professor of medicine and adjunct professor of public health at the University of California, Los Angeles, said recommendations for treating COVID-19 are “not completely clear,” and clinician and patient compliance is not always perfect.
“Fortunately, since there's not that much COVID-19 activity, it hasn't affected us much. But if the activity goes up a lot, then it could become a big problem,” he said. “Different physicians give different recommendations, and not everybody's completely clear on what to do.”
Katona said he does not foresee any major changes to the treatment guidelines occurring anytime soon.
“There's little financial incentive to develop more treatments to something that seems to be fading, so I don't think that there are going to be any major changes,” he said.
Are children still vulnerable?
During the first full week of August 2024, COVID-19 was the cause of 5.8% of ED visits among children aged 5 years or younger in the U.S. — the highest proportion of COVID-19-related visits among all age groups.
There are currently three vaccine options in the U.S. for pediatric populations: Novavax’s vaccine for people aged 12 years or older, and Pfizer and Moderna’s messenger RNA vaccines for children aged as young as 6 months.
Infants younger than age 6 months are likely to be protected against COVID-19 through passively transferred antibodies from their mother, “who has been either naturally infected or vaccinated, or both,” Offit said.
“Those antibodies will then fade after about 6 months,” he said.
Findings published in MMWR in 2023 showed that infants born to mothers who received a COVID-19 vaccine during pregnancy were less likely to be hospitalized for COVID-19.
Unlike in other countries, the CDC recommends that everyone aged 6 months or older in the U.S. receive an annual COVID-19 shot after completing their original series. Compared with adults, children are less likely to be vaccinated. As of Jan. 13, 2025, CDC data showed that 11.1% of children aged younger than age 18 years received a dose of 2024-2025 COVID-19 vaccine compared with 23% of adults.
“Children need to be vaccinated,” Offit told Healio | Infectious Disease News. “There is now a wealth of safety data on children aged less than 5 years regarding this vaccine, so we know the vaccine is safe, we know that it is effective, and we know that this virus is going to continue to circulate.”
What’s the latest on long COVID?
The risk for long COVID has decreased by roughly two-thirds over the course of the pandemic, with more than 70% of the reduction in cases attributable to COVID-19 vaccines, according to a study published in The New England Journal of Medicine last year.
Despite fewer people experiencing long-term symptoms after recovery from a SARS-CoV-2 infection, studies have shown that the number of people with long COVID is still large, and several questions remain on how to diagnose, treat and prevent it, according to Ziyad Al-Aly, MD, senior clinical epidemiologist at Washington University School of Medicine in St. Louis.
“There is a lot that needs to be done to phenotype long COVID — it is not one single monolithic entity. Phenotyping and classifying long COVID will also help accelerate drug discovery,” Al-Aly said, adding that “we need biomarkers or at the very least consensus on diagnostic criteria for long COVID.”
Recent data linked to the NIH’s RECOVER initiative suggested that women have a more than 30% higher risk for long COVID, with age, pregnancy and menopause affecting this risk, and that racial and ethnic differences may also affect long COVID risk.
According to Al-Aly, although vaccines have consistently been found in studies to reduce the risk for long COVID, and some data suggest that antivirals may do the same, the lack of validated treatments or FDA-approved medications is a “key knowledge gap” in battling long COVID.
“Unfortunately, there has not been a lot of progress in this area,” he said. “There are a lot of small trials ... but no actual progress yet. Overall, there is a lack of coordination and lack of urgency in this area. These two factors slow down progress significantly.”
The long-term outlook for people with long COVID is also cause for concern, Al-Aly said.
According to a recently published study, nearly 5% of people with a SARS-CoV-2 infection go on to experience myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), the symptoms of which overlap significantly with long COVID, according to Walter Koroshetz, MD, director of the NIH’s National Institute of Neurological Disorders and Stroke. Cases of ME/CFS are now 15 times higher than before the COVID-19 pandemic, the study found.
Koroshetz told Healio | Infectious Disease News in January that future long COVID research should include consideration for ME/CFS, given that nearly 90% of people in the study who experienced the condition after COVID-19 also had been diagnosed with long COVID.
“We are concerned about the long-term health trajectory of affected people,” Al-Aly said. “We have individuals who have been suffering from long COVID for nearly 5 years and have not experienced any measurable improvement. There is a huge concern about the downstream implications — the 7-year, 10-year and 15-year health trajectory of these individuals — and potential reduction in life expectancy.”
References:
- CDC. COVID data tracker. https://covid.cdc.gov/covid-data-tracker/#datatracker-home. Last updated Jan. 21, 2025. Accessed Jan. 27, 2025.
- CDC. Interim clinical considerations for use of COVID-19 vaccines in the United States. https://www.cdc.gov/vaccines/covid-19/clinical-considerations/interim-considerations-us.html. Updated Oct. 31, 2024. Accessed Jan. 17, 2025.
- CDC. Protecting infants and children from COVID-19-associated hospitalization. https://www.cdc.gov/ncird/whats-new/protecting-infants-and-children-from-covid-19-associated-hospitalization.html. Updated Oct. 2, 2024. Accessed Jan. 17, 2025.
- CDC. Staying Up to Date with COVID-19 Vaccines. https://www.cdc.gov/covid/vaccines/stay-up-to-date.html. Updated Jan. 7, 2025. Accessed Jan. 21, 2025.
- CDC. Types of COVID-19 treatment. https://www.cdc.gov/covid/treatment/index.html. Updated Dec. 24, 2024. Accessed Jan. 16, 2025.
- CDC. Vaccination trends. https://www.cdc.gov/respiratory-viruses/data/vaccination-trends.html. Updated Jan. 13, 2025. Accessed Jan. 17, 2025.
- CDC. Wastewater COVID-19 national and regional trends. https://www.cdc.gov/nwss/rv/COVID19-nationaltrend.html. Updated Jan. 16, 2025. Accessed Jan. 16, 2025.
- IDSA guidelines on the treatment and management of patients with COVID-19. https://www.idsociety.org/practice-guideline/covid-19-guideline-treatment-and-management. Last updated Aug. 12, 2024. Accessed Jan. 27, 2025.
- Link-Gelles R, et al. MMWR Morb Mortal Wkly Rep. 2024;doi:10.15585/mmwr.mm7304a2.
- Pekar JE, at al. Science. 2022;doi:10.1126/science.abp8337.
- Simeone RM, et al. MMWR Morb Mortal Wkly Rpt. 2023;doi:10.15585/mmwr.mm7239a3.
- WHO. WHO COVID-19 dashboard. https://data.who.int/dashboards/covid19/cases?n=o. Updated Dec. 29, 2024. Accessed Jan. 16, 2025.
- Worobey M, et al. Science. 2022;doi:10.1126/science.abp8715.
For more information:
Ziyad Al-Aly, MD, can be reached at mmc@wustl.edu.
Lawrence O. Gostin, JD, can be reached at gostin@georgetown.edu.
Gigi Gronvall, PhD, can be reached at centerhealthsecurity@jhu.edu.
Peter Katona, MD, can be reached at marcomm@ph.ucla.edu.
Walter Koroshetz, MD, can be reached at mmc@wustl.edu.
Paul A. Offit, MD, can be reached at offit@chop.edu.
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