(CNN)The US surpassed 700,000 deaths from Covid-19 on Friday, 108 days after the country reached 600,000 deaths from the virus, according to data from Johns Hopkins University.
The grim figure comes after another violent round of surging of infections, hospitalizations and deaths fueled by the highly transmissible Delta variant and largely driven by unvaccinated people.
The toll means the US continues to have more Covid-19 deaths than any other the country in the world, with Brazil, which has the second-highest number, reporting more than 597,000 deaths while India, third, reporting more than 448,000 deaths.
Local leaders and businesses across the country have worked to implement vaccine mandates in hopes of encouraging more people to get their shots and help curb another surge of cases in the coming months. And while governors across the US have now begun reporting encouraging signs of slowing cases and hospitalizations, they stress the most powerful tool to keep those numbers from ticking back up are vaccinations.
California Gov. Gavin Newsom said Friday his state will become the nation's first to require Covid-19 vaccinations for students.
The mandate will be a condition of in-person attendance for the six million students in the state's public schools. Independent study is an option for those unvaccinated, Newsom's office said in a release. In August, the state required all school staff to either show proof of Covid vaccination or submit to weekly testing.
"This will accelerate our effort to get this pandemic behind us," Newsom told CNN's Ana Cabrera, minutes after making the announcement.
Pill to treat Covid-19 cuts the risk of death by half, Merck says
Meanwhile, a pill has cut the risk of hospitalization or death from Covid-19 by half in a study, Merck and Ridgeback Biotherapeutics said Friday.
It would become the first oral medicine that fights viral infection for Covid-19 if approved by the US Food and Drug Administration for emergency use authorization.
"At the interim analysis, molnupiravir reduced the risk of hospitalization or death by approximately 50%," Merck said in a news release. "7.3% of patients who received molnupiravir were either hospitalized or died through Day 29 following randomization (28/385), compared with 14.1% of placebo treated patients (53,377). Through Day 29, no deaths were reported in patients who received molnupiravir, as compared to 8 deaths in patients who received placebo."
Merck said it will seek FDA emergency use authorization "as soon as possible."
Molnupiravir is not a vaccine, but a potential treatment for patients infected with the coronavirus. It is an oral antiviral, and experts have said developing such a drug could be the next chance to thwart Covid-19. A short-term regimen of daily pills would aim to fight the virus early after diagnosis and prevent symptoms from developing after exposure.
Merck has been producing doses while awaiting the study results and expects to produce 10 million by the end of the year. One antiviral drug has been approved to treat Covid. Remdesivir is given intravenously to sick patients in the hospital. It is not meant for early, widespread use.
Some states are seeing increased vaccinations
More states and health care systems are moving toward mandatory inoculations for certain workers. Officials hope the incentive of employment will eliminate hesitancy over Covid-19 vaccines -- while one governor is making contingency plans.
Connecticut Gov. Ned Lamont has instructed the National Guard to prepare in case of staffing shortages when a mandate and testing requirement go into effect at the end of Monday. State employees must provide proof of vaccination or submit to weekly tests; those who don't will be put on unpaid leave.
As of Thursday, more than 63% -- 20,000 employees -- were fully vaccinated, while 12% of employees have started weekly testing, Lamont said. More than 8,000 non-compliant employees remain, yet some 2,000 have updated their status in the last two days.
"We have provided most state employees with the option to get tested weekly instead of getting vaccinated, providing more flexibility than our neighboring states. We have also provided our employees with a compliance grace period. There is no reason all our employees should not be in compliance," Lamont said.
Connecticut is one of several states that face pushback over mandating vaccinations for critical workers. Health experts say it is necessary to protect people at a higher risk for Covid-19. But it has been met with resistance from a minority wishing to remain unvaccinated and in their current roles.
In Rhode Island, the Health Department announced in August that "all employees, interns, and volunteers in RIDOH-licensed healthcare facilities" would be required to get their first dose of the vaccine by Friday.
Care New England, one of the largest hospital systems in the state, reported Thursday more than 95% of its health care employees have been vaccinated. Staff vaccination "continues to climb by the day and the hour," said CEO James E. Fanale.
The deadline has passed in other states. California's 2 million health care workers needed to be vaccinated by Thursday or risk losing their jobs, with exemptions available for religious beliefs or qualifying medical reasons.
In New York, none of the health care facilities shut down as a result of vaccine mandates for workers, Gov. Kathy Hochul said Thursday. Earlier this week, it was reported 92% of nursing home staff, 89% of adult care facilities staff, and 92% of hospital staff have received at least one dose statewide.
"You will see that number go higher quickly, because what we're finding is, you know, as more people are furloughed or suspended, that that number is going to go up," Hochul said.
A group of public school teachers asked the Supreme Court on Thursday to block the New York City vaccine mandate for public school employees. Justice Sonia Sotomayor on Friday denied that request.
New York City's teachers are now 93% vaccinated, with the deadline at the end of the day, Mayor Bill de Blasio said Friday morning.
New York City Schools Chancellor Meisha Porter said she does not expect to have a shortage of teachers on Monday.
"We have more subs that are vaccinated than unvaccinated. Teachers and our superintendents have been working with our principals to develop plans to ensure our students get the education and continue to get the education they deserve in person," Porter told CNN.
Vaccines for younger kids may be available soon, but poll finds hesitancy remains
Despite evidence vaccinations are lowering infections and severity among eligible age groups, hesitancy remains among some parents about inoculating children 5 to 11, a survey says.
One-third of parents of 5- to 11-year-olds say that they will vaccinate their child as soon as possible, according to the Kaiser Family Foundation Vaccine Monitor on Thursday. A similar percentage, 32%, say that they will wait and see how the vaccine is working, and 24% say that they definitely won't get their kids vaccinated.
The bulk of interviews, conducted September 13 to 22 from a sample of more than 1,500 adults, were before Pfizer announced that clinical trials showed their Covid-19 vaccine was safe and generated an immune response in this age group.
The Pfizer/BioNTech vaccine is approved for people age 16 and older and has an emergency use authorization for people ages 12 to 15.
Friday, the FDA announced two meetings of its vaccine advisers, including one October 26 to discuss Pfizer's Covid-19 vaccine for children 5 to 11. Pfizer has submitted data about the age group to the agency but has not yet formally requested emergency use authorization.
The group of advisers will also meet October 14 and 15 to discuss boosters for the two-dose Moderna Covid-19 vaccine and Johnson & Johnson's single-shot vaccine. The agency added the group will also discuss data on "mix and match" boosters.
Study: Unvaccinated people who get Covid-19 likely to get it again
One new study, published Friday in the journal The Lancet Microbe, suggests people who get sick with the virus have some protection against reinfection but it may be short-lived.
"Reinfection can reasonably happen in three months or less," Jeffrey Townsend, a professor of biostatistics at the Yale School of Public Health and the study's lead author, said in a news release. "Therefore, those who have been naturally infected should get vaccinated. Previous infection alone can offer very little long-term protection against subsequent infections."
Researchers looked at the behavior of related coronaviruses like MERS, SARS and those that cause the common cold and used what they knew about the evolution of those viruses to create a model that accounts for the projected evolution of the virus behind the current pandemic. They then used the model to assess the risk the virus poses for reinfection.
They saw the viruses behaved in a similar fashion and posed similar reinfection risks. In endemic conditions and without vaccination, reinfection with the virus that causes Covid-19 "would likely occur between 3 and 63 months after peak antibody response," the authors wrote, with a median of about 16 months.
"We tend to think about immunity as being immune or not immune. Our study cautions that we instead should be more focused on the risk of reinfection through time," said study co-author Alex Dornburg, assistant professor of bioinformatics and genomics at the University of North Carolina at Charlotte. "As new variants arise, previous immune responses become less effective at combating the virus. Those who were naturally infected early in the pandemic are increasingly likely to become reinfected in the near future."
Covid nursing home deaths quadrupled between July and August, analysis finds
After reaching an all-time low in June with the help of vaccinations, Covid-19 deaths in US nursing homes quadrupled between July and August 2021, according to a report published Friday by the Kaiser Family Foundation.
Though weekly Covid-19 cases and deaths in long-term care facilities declined following the rollout of vaccines in the winter, the KFF analysis of federal data found cases and deaths rose sharply amid the spread of the Delta variant in August.
Nursing home residents are among the groups eligible for a booster dose of the Pfizer Covid-19 vaccine. The Biden administration has also announced a staff vaccination mandate for nursing homes.
"Vaccines coupled with boosters may reverse the recent trend of rising cases and deaths within nursing homes, though ongoing spread in the community continues to have an impact on residents and staff," the report said.
Nursing homes reported nearly 1,800 Covid-19 deaths among residents and staff in August, up from about 350 deaths in July 2021. August deaths were at the highest level reported in a single month since February 2021.
But it was still far below the peak of more than 22,000 Covid-19 deaths seen in December.
Covid-19 cases in nursing homes rose by 440%, from 9,000 to 48,800, between July and August, while cases in the general population rose by 224%, from 1.3 million to 4.2 million, according to KFF.
Correction: An earlier version of this story incorrectly identified a drug maker involved in the production of molnupiravir. It is Ridgeback Biotherapeutics.