WASHINGTON -- US COVID-19-related deaths on Monday surpassed 675,000, the estimated US fatalities from the 1918 influenza pandemic, while battles over vaccines and masks continue as the country staggers into the 19th month of the pandemic.

As of 4:21 pm ET (2021 GMT) on Monday, 675,446 Americans were killed due to COVID-19, with the total caseload exceeding 42 million, according to a tally by Johns Hopkins University.

The fatalities are expected to continue to rise as the country is currently experiencing another wave of new infections, fueled by the fast-spreading Delta variant.

"We cannot become hardened to the continuing, and largely preventable, tragedy," Tom Frieden, the former head of the Centers for Disease Control and Prevention (CDC), tweeted earlier this month, noting deaths from COVID-19 in the United States would surpass the toll of the 1918 flu pandemic.

The dismal milestone of surpassing the 1918 death toll came as Americans are still divided over mask and vaccine mandates.

Early this month, US President Joe Biden announced a six-pronged national strategy as a path to ending the pandemic.

As of Monday, over 181.7 million Americans, or 54.7 percent of the US population, have been fully inoculated, according to the CDC. 

Expressing his frustration with the roughly 80 million Americans who are eligible for shots but have not gotten them, Biden is requiring all businesses with 100 or more employees to ensure their workers are either vaccinated or tested weekly.

Biden's new vaccine mandates, which could apply to as many as 100 million Americans, or almost two-thirds of the American workforce, have spawned a strong pushback from quite a few Republican states and unions.

Also, many Americans believe whether to get vaccinated should be a personal decision, instead of a government mandate.

Polls show that those who reject vaccines are more worried about possible side effects of the vaccines than they are about COVID-19. Social media are also rife with conspiracy theories about vaccines.

Nationwide, American parents are torn apart by the conflicts among school boards, Republican states and the Biden administration over how to make schools open and safe.

As of Sept 16, over 5.5 million children and adolescents had tested positive for COVID-19 since the onset of the pandemic, according to the latest report by the American Academy of Pediatrics.

The US Education Department has recently announced it is investigating the state of Florida over its ban on mask mandates in the state's public schools, after an appeals court in the state reversed a lower court's ruling and allowed the ban to stay.

Florida's Republican Governor Ron DeSantis issued an executive order on July 30, banning mask mandates at public schools to ensure parents' freedom to choose. The order includes a policy of withholding funds from school districts that defy the governor's order.

However, 13 of Florida's 67 school districts have strict mask requirements, in defiance of the state, local newspaper Miami Herald reported. Biden's administration has offered financial aid for schools in Florida affected by DeSantis' policy.

In addition to Florida, Texas, Nebraska and quite a few other Republican states have issued a mask mandates ban, contradicting the CDC guidance of universal indoor masking for all teachers, staff, students, and visitors to K-12 schools.

Emma Cheng, a mother of two young boys at Marengo Elementary School in east Los Angeles, California, gave her full and unwavering support to the school's mask mandate. "We must follow the science, and it is that simple," Cheng told Xinhua.

"We support the school mask mandate especially since our little ones cannot be vaccinated yet," said Hector Lopez, who has a seven-year-old boy at the school.

Cheng joined over 150 others to sign a petition called "Vaccinate SPUSD (South Pasadena Unified School District)" to demand that their school district vaccinate teachers of children under 12 years old.

Many private schools have implemented a mask policy long before the states' order was announced. With mask requirements in place, Notre Dame Academy, a private Catholic school for girls in New York, has managed to stay open throughout the entire pandemic.

"Masking is not a thing that bothers parents or a challenge to their parenting rights," said Y.C. Hoerle, who has a high school freshman at the school.