News Release

Curing Long-Term Covid Infections Could Slow Viral Evolution


As the United States finds itself in the midst of its second surge of 2022, public health experts are returning to a longtime question of the pandemic: When will––or will––it end?

BILL HANAGE, PhD, contact to schedule interviews
    Hanage is an associate professor of epidemiology at Harvard University.

JOHN DENNEHY, PhD,, @DrJDennehy 
    Dennehy is a professor of biology and deputy executive officer of the Biology PhD Program at Queens College and The Graduate Center of CUNY.

Dr. Hanage noted in an interview that “we’ve got to remember that [Covid] is something we’re going to be fighting with for a hell of a long time.” He told the Institute for Public Accuracy that we know that Covid is not currently endemic because we are still witnessing dynamics that are characteristic of a pandemic––including surges at any point of the year, unlike with other seasonal coronaviruses. 

In a new letter published May 21 in the Lancet, five scientists write that the pandemic has been characterized by waves of variants, and that “preliminary evidence suggests at least some have emerged from long-term [Covid] infections, such as those observed in immunocompromised patients [who can have difficulty eliminating Covid infections]. As a result,” the authors agree, “it is of the utmost urgency that those with long-term infections should be able to access quality health care and be prioriti[z]ed for curative therapy because a failure to properly manage these infections poses a risk to the individual and to public health.” 

In comparison with ordinary transmission chains, long-term infections may result in greater and more rapid viral evolution. Dr. Denney told the Institute for Public Accuracy today: “In persistent infections, viruses continue to evolve over long periods of time without having to find a new susceptible host. Viruses within these hosts can continue to accumulate new mutations.”

Dr. Dennehy also said: “If we need to prioritize limited resources to prevent another major Covid wave, finding and curing Covid infections of immunocompromised patients should be a priority. There are multiple lines of evidence that previous variants of concern emerged from long-term, persistent infections of immunocompromised patients. It’s reasonable to expect that they could be a source of future variants of concern. Curing these infections not only helps these individuals, but also could protect us all if another major Covidwave is not avoided. 

“Scientists have developed several therapies for Covid, including monoclonal antibodies and Paxlovid. Efforts to develop new and improved therapies are continuing. This is especially important since there is considerable evidence that [the virus] is evolving resistance to current treatments [like Paxlovid].

“Combatting the pandemic is hampered by the fact that the virus can cross jurisdictional boundaries, but there are no agreed upon pandemic response standards, based on scientific evidence, evenly applied across the world. Ultimately it is up to local authorities to find and treat persistent Covid infections in their own jurisdictions. The more authorities are aware of these priorities and implementing them in their jurisdictions, the more successful we will be in limiting virus evolution globally.”