Virginia tightened its coronavirus restrictions Friday in response to a surge in infections as the greater Washington region registered record caseloads for a 10th consecutive day.

Gov. Ralph Northam (D) lowered the number of people allowed for gatherings indoors or outdoors from 250 to 25 and imposed new limits on restaurants and businesses. A flurry of new restrictions this week has coincided with a surge in cases across the region as health experts and leaders fear that worse is ahead.

The new guidelines in Virginia, which go into effect at 12:01 a.m. Monday, require restaurants to stop serving alcohol after 10 p.m. and to close by midnight. Virginia law does not recognize bars as distinct from restaurants, and current restrictions already ban bar-style seating.

Northam is also strengthening enforcement policies for essential businesses such as grocery stores and pharmacies, making it a Class 1 misdemeanor to violate requirements to wear a mask, socially distance and practice hand-sanitizing. Until now, that potential penalty was in place only for nonessential businesses.

“While our cases are not rising as rapidly as some other states, I don’t intend to wait until they are,” Northam said through spokeswoman Alena Yarmosky. She added: “This is an attempt to really get a hold of this in Virginia.”

The restrictions also lower the age at which a person must wear a mask in public places to 5. Mask-wearing was previously required for people 10 and older.

Northam’s announcement marks the first statewide tightening of coronavirus restrictions since Virginia began to loosen its guidelines in June. Northam had imposed tighter restrictions in the Hampton Roads region over the summer in response to a spike in infections but has since lifted those.

In recent weeks, the southwest portion of the state has seen a sharp rise in infections. Its positivity rate is more than 9 percent, double that of some other parts of Virginia, although all of the state’s health districts are seeing increases.

Del. Todd Gilbert (R-Shenandoah), the House minority leader, criticized Northam’s action. He tweeted that the new restrictions were “drastic . . . and confusing” and said it was “incredibly disappointing” for Northam to make the announcement on a Friday afternoon without taking questions. “That is not how you govern,” Gilbert tweeted.

In Maryland, the rate of infections has nearly doubled in about two weeks, culminating in a record number of new cases Friday. The rolling seven-day average of new infections in Maryland surged to 1,466, a number that stood at 741 daily cases Oct. 28.

The 1,869 new cases Friday in Maryland was the most in a single day since the start of the pandemic. The number of hospitalizations in the state reached the highest level since June 11.

Maryland Gov. Larry Hogan (R) reimposed pandemic-related restrictions this week — as did several jurisdictions across the state — hoping to slow the highly contagious virus that is ravaging Maryland and the nation. Hogan has said the state is prepared to handle the surge but warned that more challenges lie ahead.

“These weeks and months ahead will be the most difficult we have faced,” Hogan tweeted Friday. “Wear a mask, wash your hands, watch your distance. Stay #MarylandStrong.”

Maryland’s seven-day average caseload is on track to overtake that of more populous Virginia, which has long had a higher number of cases. Virginia is averaging 1,499 daily cases, down slightly compared with the last two days.

The United States is recording a seven-day average of 40 new coronavirus cases daily per 100,000 residents. Despite the surge of infections in the Washington area, the region’s rate of spread is still about half the national average — with 24 new daily cases per 100,000 residents in Maryland and 18 in Virginia and D.C.

Only four states are recording a lower rate of infection than Virginia and the nation’s capital: California, Maine, Vermont and Hawaii.

Friday is the 10th consecutive day that the seven-day average number of new cases in Virginia, Maryland and D.C. has hit a record. That number stood Friday at 3,090 daily cases, up from 1,313 on Oct. 1.

Boris Lushniak, dean of the University of Maryland School of Public Health, said the Washington region is “following not just the national trend but the worldwide trend” as cases tick upward. He said U.S. caseloads often follow those in Europe by two to four weeks, with that continent recently recording large spikes in cases.

“In Europe, in the U.S. and the DMV region, we’re seeing a third wave,” said Lushniak, who served as the U.S. deputy surgeon general from 2010 to 2015. “We always knew the fall would bring a worsening of the situation.”

He blamed fatigue with following virus health protocols and cooler weather for the rise in cases. Lushniak said infection rates in the Washington region have generally been better than in many parts of the country, but that could be changing.

“We’re regressing,” he said. “We’re going back to where we were. This is going to get much more serious.”

Lushniak said residents should remain vigilant against the virus, particularly with the holidays approaching. To avoid tougher restrictions, he said, people need to wear masks, maintain social distancing and not host or attend large gatherings.

A refusal to follow those standard health guidelines could result in “more drastic measures” to avoid putting a strain on the region’s health-care system, he said.

The surge prompted Maryland and several of its largest jurisdictions this week to enact policies to combat the virus’s spread. Hogan reimposed statewide restrictions — with local governments able to impose more restrictive policies — that had not been in place since the summer.

Baltimore County on Friday became the latest Maryland locality to toughen its pandemic-related policies. Youth sports will be canceled starting Tuesday, while social gatherings will be capped at 10 people indoors and 25 people outside, effective Sunday. Bars and restaurants must close at midnight.

“Now is the time to take action,” Baltimore County Executive Johnny Olszewski Jr. (D) said in a statement. “We all want to get back to normal, we want to go about our lives without restrictions and we want our kids back in school, but none of that can happen unless we all do our part.”

The Frederick County Board of Health late Thursday passed new mask requirements, limited the size of religious gatherings to 50 percent of a building’s capacity, and capped other indoor and outdoor social gatherings and business venues at 25 people or 25 percent capacity. Violations can carry escalating fines that start at $250.

Prince George’s and Anne Arundel counties joined Baltimore City on Thursday in implementing strict limits for indoor social gatherings, forbidding groups of more than 10 people inside and lowering capacity at some retail establishments. The Prince George’s order, which goes into effect 5 p.m. Sunday, also requires that residents wear masks when outside unless vigorously exercising.

Montgomery County lawmakers approved an order to limit gatherings to a maximum of 25 people and reduce capacity for restaurants and shops from 50 percent to 25 percent. Other counties have said they are considering tougher pandemic-related measures.

D.C. has not announced new restrictions amid the rise in cases.

The greater Washington region recorded 3,263 additional cases and 39 deaths Friday. Virginia added 1,235 cases and 27 deaths, Maryland added 1,869 cases and 12 deaths, and D.C. added 159 cases and no deaths.

Rachel Chason contributed to this report.