The omicron variant may create mild COVID-19 symptoms and reinfect previously infected COVID-19 patients, but it could have a shorter incubation time than previous COVID-19 strains, according to a new Centers for Disease Control and Prevention report.
CDC investigates omicron variant spread
The CDC recently examined what happened to a Nebraska patient —who was reportedly infected with the omicron variant — and the patient’s household.
- The patient, who was unvaccinated, had previously acquired symptomatic COVID-19 in November 2020.
According to the CDC, the patient had unmasked close contact with a masked, coughing person on Nov. 20 while at an international conference in Nigeria, which included people from multiple African countries.
- The patient tested negative for COVID-19 before his return to the U.S.
The patient — who was asymptomatic when he returned to the U.S. — had unmasked close contact with five household contacts, according to the CDC.
- One household contact was fully vaccinated (the person’s second Pfizer COVID-19 vaccine dose was received in August 2021). This patient had COVID-19 in November 2020, too.
- Three of the contacts were unvaccinated and had symptomatic COVID-19 in November 2020.
- One contact was unvaccinated and had “mild upper respiratory symptoms in November 2020, just before illness onset in the other household members,” according to the CDC. But the patient received a negative COVID-19 test.
- None of the household members said they had underlying medical conditions or immunocompromising conditions.
- So this means that one of the patients experienced reinfection after having being fully vaccinated. Four patients experienced reinfection. One experienced their first infection.
What this means for omicron variant symptoms, reinfection
According to the CDC, this may suggest that the omicron variant has an “incubation period and a clinical syndrome similar to or milder than that associated with previously described variants in persons who have been vaccinated or previously infected.”
- This case suggests there’s “an increased potential for reinfection,” too, per the CDC.
This CDC investigation may also show that the spread of omicron may take only three days after incubation compared to about five days with the other COVID-19 strains.
- “It is unknown whether the mild clinical syndromes or differing symptom descriptions are a result of existing immunity or altered clinical features associated with Omicron infection,” the CDC said. “The five reinfections, including one after full vaccination, might be explained by waning immunity, the potential for partial immune evasion by Omicron, or both”