San Francisco, the first U.S. city to declare a monkeypox state of emergency, will end the designation at the end of the month, Novavax's Covid-19 vaccine has been authorized as a booster shot for adults, and more in this week's roundup of monkeypox and Covid-19 news.

Monkeypox:

• According to CDC, as of Oct. 12, the United States recorded a seven-day average of 60 monkeypox cases, representing the lowest recorded average since June. Shira Doron, an infectious disease physician and hospital epidemiologist at Tufts Medical Center, said the outbreak has slowed for a few reasons. "There were really substantial changes among men who have sex [with] men," she said. She also credited vaccines with slowing the spread of the disease. However, Doron added, "As we have learned and seen with COVID, case numbers have a certain shape and what goes down can come up again … So, we can't rest on our laurels and think that's it over." (Kekatos, ABC News, 10/17)

• CDC on Monday reported the first U.S. monkeypox case in a health care worker since the start of the outbreak. A Florida hospital nurse was exposed to the virus through a needlestick. And although she received a first dose of Jynneos' monkeypox vaccine 15 hours after exposure, she still developed symptoms and tested positive for the virus 10 days later. The nurse isolated at home for 19 days, and no secondary cases were identified. (American Hospital Association, 10/17; Bean, Becker's Hospital Review, 10/18)

• The San Francisco Department of Public health on Thursday announced that the city's state of emergency, which was declared over the monkeypox outbreak on July 28, will end Oct. 31. "The public health emergency declaration on MPX [monkeypox], the first of its kind in the nation, served its purpose to reflect the immediate urgency of the MPX threat to the health of those most affected in the gay, bisexual and trans communities," the department stated. "It also gave public health officials tools, such as collection of critical data, needed to respond effectively." In the last month, there were only 33 reported monkeypox cases in San Francisco. (Ferrannini, KRON4, 10/20)

Covid-19:

• Researchers at Boston University (BU) tested a lab-made hybrid version of SARS-CoV-2, which has prompted controversial attention. In an animal model, BU researchers combined the omicron spike protein with the ancestral strain of the virus and tested the new strain on mice. They found that the naturally circulating omicron variant caused mild, non-fatal infection, but the combined virus inflicted severe disease with a mortality rate of 80% in 10 mice. Notably, the original ancestral strain killed 100% of mice tested with the strain. Ronald Corley, director of the BU National Emerging Infectious Diseases Laboratories and chair of microbiology at the Chobanian & Avedisian School of Medicine, explained on Monday that the "80% kill rate" figure that has been circulating in news headlines "totally misrepresents not only the findings, but [also] the purpose of the study." BU also said in a statement, "First, this research is not gain-of-function research, meaning it did not amplify the [ancestral] SARS-CoV-2 virus strain or make it more dangerous … In fact, this research made the virus [replication] less dangerous." The university went on to add that the work was approved by the Institutional Biosafety Committee as well as the Boston Public Health Commission. (Branswell, STAT, 10/17; Henderson, MedPage Today, 10/18; Casiano, Fox29, 10/17)

• News this month that monoclonal antibody treatments are ineffective against rising variants has led Biden health officials to race "to game out other antibody options and convene a meeting with patient groups." AstraZeneca's Evusheld is currently the only monoclonal antibody drug authorized as a periodic injection to prevent infection. It is used by roughly 17,000 Americans with weakened immune systems that may not produce immune responses via vaccination. However, FDA this month updated its Evusheld factsheet to note that it is not effective against BA.4.6, the strain that currently makes up at least 13% of Covid-19 cases. In addition, Eli Lilly's monoclonal antibody treatment, bebtelovimab, is ineffective against the other fast-rising variant, BQ.1. An FDA spokesperson said the agency, "will provide additional updates to the EUA materials, as appropriate, as new information emerges." (Owermohle, STAT, 10/18)

• FDA granted and CDC endorsed emergency use authorization to Novavax's Covid-19 shot as a booster for adults who received a primary vaccine series at least six months prior. The shot targets only the original strain of the virus, whereas Pfizer-BioNTech and Moderna's updated boosters target both the original strain and newer omicron strains. "According to CDC data, almost 50% of adults who received their primary series have yet to receive their first booster dose," said Stanley Erck, Novavax's president. "Offering another vaccine choice may help increase Covid-19 booster vaccination rates for these adults." (Whyte, Wall Street Journal, 10/19)