Smallpox vaccine given years before 72% to 75% effective against mpox, data reveal

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mpox virus
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In a research letter today in the New England Journal of Medicine, researchers estimate that a smallpox vaccine dose given a median of 13 years earlier is 72% to 75% effective against mpox among US veterans.

Researchers from Emory University and the Veterans Affairs (VA) Healthcare System conducted a retrospective, test-negative study involving 1,014 current and former military personnel with mpox symptoms tested for orthopoxvirus (eg, smallpox, cowpox, mpox) from July 1 to October 31, 2022.

The researchers identified participants using Department of Defense electronic lab data and the VA Corporate Data Warehouse. From 2002 through 2017, more than 2.6 million military personnel received smallpox vaccinations (Dryvax, ACAM2000, or Jynneos, which is also approved for mpox) as part of their military deployment or occupational requirements.

"During the ongoing global outbreak of mpox (formerly called monkeypox), smallpox vaccines have been used to prevent infection and reduce the severity of disease in those at increased risk for infection," the study authors wrote. "However, the effectiveness of smallpox vaccines against mpox is unknown."

ACAM2000 may have slight edge over Dryvax

A total of 184 participants (18%) had received a smallpox vaccine a median of 13 years before. Of the 293 veterans (29%) who tested positive for orthopoxvirus, 3% had been vaccinated with Dryvax (first-generation smallpox vaccine), and 7% had received ACAM2000 (second-generation).

Veterans vaccinated against smallpox were less likely to test positive for mpox than those with no record of vaccination (odds ratio [OR], 0.28; 95% confidence interval [CI], 0.13 to 0.58 for Dryvax and 0.25 [95% CI, 0.15 to 0.42] with ACAM2000). Estimated vaccine effectiveness was 72% for Dryvax and 75% for ACAM2000.

Previous vaccination at a median of 13 years earlier with either a first- or second-generation smallpox vaccine reduced the likelihood of testing positive for orthopoxvirus among current or former military personnel.

Of 293 orthopoxvirus-positive veterans, 41% had HIV (OR, 2.34; 95% CI, 1.65 to 3.35). In the VA part of the study, 19 of 186 participants (10%) were hospitalized, but none died.

"Previous vaccination at a median of 13 years earlier with either a first- or second-generation smallpox vaccine reduced the likelihood of testing positive for orthopoxvirus among current or former military personnel," the authors concluded.

Study: COVID therapeutics not available evenly across US

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iv bagsAccess to COVID-19 therapeutics, like almost every other facet of the pandemic, is defined by sociodemographic-based disparities, according to a new survey published in JAMA Network Open.

The study was based on data taken from the COVID-19 Public Therapeutic Locator, and the researchers paired the data with county-level population to assess geospatial differences in access to COVID-19 therapeutics, including monoclonal antibodies.

Counties were grouped into cluster types, including high-high clusters (counties with higher availability), low-low clusters (counties with lower availability), high-low and low-high outliers (counties with either high or low levels of availability surrounded by counties with either low or high levels of availability), and unclustered (counties with neither high nor low levels of availability).

Counties with low income had less access

The county-level analysis shows counties with high poverty and uninsured rates, as well as a high number of Black residents, had significantly lower access to COVID-19 therapeutic drugs.

COVID-19 treatments were highly available (39.08-854.70 per 100,000 people) in some parts of New England, Kansas, and across the United States. Overall, the higher the household income in a county, the more access residents had to COVID-19 therapeutics.

"High-high clusters around Maine, western Kansas and Nebraska, and eastern Montana," the authors wrote. "Low-low clusters appeared across the South and Midwest regions and some parts of the Western region."

The authors said this information provides essential knowledge for the next phase of the pandemic.

"With the end of the COVID-19 Public Health Emergency, these results highlight an important gap in treatment access," the authors wrote.

Risk of long COVID goes up with previous diagnoses

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tired womanA large study in Norway reveals that the risk of long COVID after a mild infection is about double among people who, before their COVID-19 infection, had been diagnosed as having psychological, respiratory, or general or unspecified health problems.

The study is published in Nature Communications and is based on health data from 214,667 SARS-CoV-2–infected individuals who diagnosed with the virus from July 1, 2020, to January 24, 2022. The mean age was 44.6 years, and 50% were women. A total of 0.42% (908) were diagnosed as having post-COVID condition (PCC).

Twenty-one percent had PCC-related respiratory problems, and 60% said they experienced fatigue.

The strongest association for developing PCC was female sex (odds ratio [OR],  2.17; 95% confidence interval [CI], 1.89 to 2.50) and infection with the ancestral SARS-CoV-2 strain (OR, 4.00; 95% CI, 3.48 to 4.6).

Researchers then looked at prior healthcare use in the 2 years before COVID-19 infections. The strongest association for developing PCC was psychological care (OR 2.12; 95% CI, 1.84 to 2.44), respiratory problems (OR, 2.03; 95% CI, 1.78 to 2.32) and general and unspecified health problems (OR, 1.78; 95% CI, 1.52 to 2.09).

"These findings imply that individuals who prior to the pandemic had a psychological diagnosis were approximately twice as likely to be classified with the post-COVID condition, compared to infected individuals without such prior diagnoses,” the authors wrote.

HHS announces boost for COVID test production, fifth round of free tests for households

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In an effort to support national production of COVID-19 tests and curb the spread of the virus, the US Department of Health and Human Services (HHS) yesterday announced investments worth $600 million split among 12 domestic test manufacturers and opened up another round of mail delivery of free COVID-19 tests to those who request them.

rapid covid test
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In a statement, the HHS said the funding through the Administration for Strategic Preparedness and Response (ASPR) will help the 12 companies employ hundreds of people across seven states and meet the goal of producing 200 million tests for government use. Dawn O'Connell, the Assistant Secretary for Preparedness and Response, said, "Manufacturing COVID-19 tests in the United States strengthens our preparedness for the upcoming fall and winter seasons, reduces our reliance on other countries, and provides good jobs to hardworking Americans."

Starting September 25, households will be able to order four free tests through COVIDTests.com. Officials said the tests will detect currently circulating variants and are designed for use through the end of 2023, though they will include instruction on how to verify if they are subject to extended expiration dates.

To date, the US government has offered four rounds of free COVID-19 tests that provided 755 million tests through the mail to American households. ASPR has also distributed 500 million free tests directly to nursing homes, low-income senior housing, uninsured people, and underserved communities.

 

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