COVID-19 Resource Center

COVID-19 Resource Center


Healio Interview

Disclosures: Kliger and Silberzweig report no relevant financial disclosures.
December 27, 2021
3 min read

Q&A: Nephrologists offer next steps in addressing the COVID-19 omicron variant


Healio Interview

Disclosures: Kliger and Silberzweig report no relevant financial disclosures.
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On Nov. 26, 2021, the WHO classified a new variant of COVID-19, B.1.1.529, as a “variant of concern” and named it omicron.

As of Dec. 8, 2021, 22 states in the U.S. reported at least one COVID-19 case attributed to the omicron variant. Among 43 cases with initial follow-up, one hospitalization and no deaths have been reported.

Jeffrey I. Silberzweig

Nephrology News & Issues interviewed Alan S. Kliger, MD, and Jeffrey I. Silberzweig, MD, on steps dialysis providers and transplant centers can take in protecting patients and staff from the omicron variant. Kliger is a clinical professor of medicine at Yale University School of Medicine and Silberzweig is the chief medical officer of Rogosin Institute. The nephrologists serve as co-chairs of the American Society of Nephrology’s COVID Response Team.

Nephrology News & Issues: What do we know about the omicron variant?

Kliger and Silberzweig: Infection with the omicron variant of COVID-19 is rapidly expanding across the globe. While the exact R0 (the measure of transmissibility or “catchiness”) is difficult to calculate because so many omicron infections cause no symptoms, testing has shown a daily increase in omicron variant infections, making this the most transmissible of all variates of COVID-19 to date.

It is likely that omicron is now the dominant variant of COVID-19 in many areas of the United States.

Nephrology News & Issues: Should all dialysis patients get a vaccine booster? What do data show in terms of efficacy?

Kliger and Silberzweig: Patients on dialysis or who have a kidney transplant are particularly vulnerable to all previous COVID variants, and we would expect the same for omicron. If infected, these patients are more likely to suffer complications and life-threatening disease than people with normal kidney function.

For patients on dialysis, “full immunization” with the available vaccines produced excellent immunity for most. Studies have shown that the level of antibody protection falls with time, and that an additional “booster” shot is needed 6 months after the last dose of the two mRNA vaccines from Moderna and Pfizer.

The booster raises antibody levels back to over 90% for most individuals. For the Johnson & Johnson “vector” vaccine, a booster shot is needed 2 months later to achieve high antibody levels.

We recommend that anyone who received a “vector” vaccine like Johnson & Johnson also receive their second immunization with one of the mRNA vaccines, either the Moderna or Pfizer vaccine.

Nephrology News & Issues: Kidney transplant patients are more vulnerable to the omicron variant because of their compromised immune system. Would a booster shot be beneficial?

Kliger and Silberzweig: Many transplant patients develop only low levels or no protective antibodies after immunization with two mRNA vaccinations or one vector vaccination. A third immunization of mRNA vaccine raises protective antibody levels in about half of transplant patients with low-level antibodies, so we strongly recommend a third shot for transplant patients.

Nephrology News & Issues: What is the latest research on antibody levels for patients on dialysis? Can this help with protection?

Kliger and Silberzweig: Antibodies are produced by the body’s immune system after infection with COVID-19, or after vaccination. It is clear that dialysis and transplant patients with protective antibodies have a lower incidence of COVID-19, and for those who do develop infection, the illness is usually mild with few or no symptoms at all.

Serious or life-threatening infections do occur, but at a frequency of about 10-fold lower than for people without antibodies. Among people infected with omicron, so far that pattern continues: People with protective antibodies can develop infection, but it is usually mild or asymptomatic.

Serious infections can develop but are less likely among those vaccinated.

Nephrology News & Issues: Should dialysis providers prepare again for setting up isolation shifts or clinics?

Kliger and Silberzweig: During the past waves of COVID-19, dialysis providers rapidly took measures to protect patients on dialysis from spreading or acquiring infections at dialysis facilities. Screening everyone entering a dialysis facility, universal masking, hand hygiene, gowns, gloves and careful surface and station disinfection reduced spread of COVID-19 in facilities to nearly zero. When community rates of infection were high and patients were filling hospitals, isolation dialysis clinics and isolation shifts were effective for the original Wuhan and delta strains of infection.

While most immunized people appear to have mild disease with omicron strain, its high transmissibility will almost certainly produce similar shortages of hospital beds and increased mortality. Under these circumstances, dialysis providers need to consider when to re-activate their plans for isolation facilities.

Nephrology News & Issues: Many in the nephrology specialty believed that the pandemic would drive more new patients to home dialysis as a protectant from the virus. That didn’t materialize. Is it still a good idea?

Kliger and Silberzweig: Dialysis is a wonderful way to limit exposure to COVID-19 and reduce the possibility of infection. Given the high transmissibility of the omicron variant, home dialysis is a particularly attractive dialysis plan to keep patients and their families safe during this pandemic.