COVID-19 mu variant has been detected in Maryland. Here's what to know.

The delta variant is still the predominant strain of COVID-19 circulating in Maryland and across the nation, but the emerging "mu" variant has made a small appearance here in recent weeks.

The World Health Organization identified the mu variant — which, like other COVID-19 variants, was named with a letter of the Greek alphabet — as a "variant of interest" on Aug. 30.

Though more research is still needed, the WHO reported last month that the mu variant has some characteristics that could make it more resistant to COVID-19 vaccines.

Is the mu variant in Maryland?

Yes, but only in very small numbers.

Since Sept. 15, Maryland has detected 56 cases of the mu variant through genetic sequencing, according to the state Department of Health.

That's a tiny fraction of the total new COVID-19 cases in Maryland. The delta variant made up more than 97% of all COVID-19 cases sequenced in the past month, according to the Centers for Disease Control and Prevention.

More:Wicomico County COVID-19 vaccine tracker: 46% of people fully vaccinated

More:More than 10,000 dead from COVID-19 in Maryland; Gov. Larry Hogan orders flags lowered

Where did the mu variant originate?

The mu variant was first identified in Colombia in January, according to the WHO. The global health organization named it a "variant of interest" on Aug. 30.

Worldwide, the mu variant makes up fewer than 0.1% of sequenced COVID-19 cases. But it has "consistently increased" in prevalence in Colombia and Ecuador, where it makes up 39% and 13% of infections, according to the WHO.

The U.S. has reported a total of 2,803 identified cases of the mu variant, according to GISAID, a database that tracks the coronavirus.

In total, the U.S. is reporting about 150,000 new COVID-19 cases per day, the CDC reports.

Is the mu variant resistant to vaccines or more contagious?

The mu variant has mutations that suggest it could be more resistant to vaccines, similar to the beta variant, which originated in South America, according to the WHO. But more research is needed, and little is known about how severe this variant could be.

Since it was first identified, there have been a few reports of outbreaks of the mu variant in South American countries and Europe, but the variant makes up less than 0.1% of sequenced cases globally.

"More studies are required to understand the phenotypic and clinical characteristics of this variant," the WHO said in its weekly epidemiological update.

What can I do?

Maryland is seeing a surge of COVID-19 cases and hospitalizations fueled by the delta variant, which remains by far the most prevalent strain of the virus. Both metrics are still below the worst days of the pandemic, which came last winter.

The CDC reports that COVID-19 vaccines continue to reduce the risk of contracting the virus, including the delta variant.

Vaccines are also highly effective at preventing hospitalizations and deaths from COVID-19, and fully vaccinated people who get "breakthrough" cases of the delta variant "appear to be infectious for a shorter period," the CDC says,

In Maryland, more than 7.7 million vaccine doses have been administered and nearly 83% of eligible adults have received at least one dose of the vaccine.

Gov. Larry Hogan recently authorized a third dose of the vaccine for certain vulnerable populations, including the immunocompromised and nursing home residents.

More:Maryland expands booster shots to nursing home residents, immunocompromised

Madeleine O'Neill covers the Maryland State House and state issues for the USA TODAY Network. She can be reached at moneill@gannett.com or on Twitter at @maddioneill.