DR Congo reports 19 new vaccine-derived polio cases

News brief

In recent days the Democratic Republic of the Congo (DRC) was the only country that reported more polio cases, all of which involved circulating vaccine-derived poliovirus type 2 (cVDPV2), the Global Polio Eradication Initiative said in its latest weekly update yesterday.

Of the 19 cases, 11 were from Tanganyika province and 5 were from Lomami province. Single cases were reported in South Kivu, Haut Katanga, and Kasai Oriental provinces. The new infections bring the country's total for the year to 210 cases. The country is also battling an outbreak involving circulating vaccine-derived poliovirus type 2 (cVDPV1).

In other developments, Afghanistan and Pakistan both reported environmental samples that were positive for wild poliovirus type 1 (WPV1), which signals ongoing circulation in the two countries.

In Africa, Botswana and the DRC reported positive environmental samples for cVDPV2. So far, Botswana hasn't reported any cVDPV2 cases, but it has now reported two positive environmental samples.

GAO: Nursing home COVID outbreaks tied to community spread

News brief

A new report from the US Government Accountability Office (GAO) shows that the average COVID-19 nursing home outbreak in 2020 to 2022 lasted 4 weeks and was strongly tied to community spread, with the longest outbreaks in government-owned facilities with more than 100 beds and staff shortages.

The GAO analyzed data from the Centers for Disease Control and Prevention (CDC) and the Centers for Medicare & Medicaid (CMS) on the nation's 15,281 Medicare- and Medicaid-certified nursing homes from June 2020 to December 2021. The agency also interviewed researchers, national nursing home associations, state officials, and leaders at six nursing homes in California, Florida, Maryland, and Michigan.

Most began with staff case

The nursing homes each experienced 1 to 16 outbreaks, with an average of 7.6 and a total of 102,992. The surges lasted, on average, 4 weeks, ranging from 1 week (42% of total outbreaks) to 53 weeks (less than 1%). Nearly all nursing homes (91%) had at least one surge of 5 or more weeks.

The strongest factor in the length of an outbreak was community spread, with those in nursing homes in areas with low COVID-19 transmission seeing surges that were 7 days shorter than those in areas with high transmission.

Most outbreaks (75%) began with a report of a staff infection. "These results could indicate that, during times of higher community spread, staff have a greater likelihood of being exposed to the virus in the community and bringing it into the nursing home," the report said.

Officials at five nursing homes described staff shortages during case surges, with one official noting that at one time, staffing was down 25%. Three officials discussed difficulties in maintaining good morale amid traumatic circumstances that took the joy out of caregiving.

"Nursing home residents are at a high risk of infection and death due to COVID-19, as older adults and those with underlying health conditions are at a higher risk of severe disease," the GAO said. "In addition, the congregate nature of nursing homes increases the risk of transmission."

Lack of rural US healthcare access led to COVID vaccine disparities, data show

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A study in The Lancet Regional Health finds that wide disparities in healthcare capacity in the United States, particularly in rural areas, hampered COVID-19 vaccination efforts during the pandemic.

The cross-sectional study was conducted by comparing the healthcare system capacity of 2,417 US counties and their COVID-19 vaccination rates. Counties with more limited healthcare capacity had COVID-19 vaccination rates less than or equal to 50%, with 35% higher constraints in low-vaccinated areas compared to high-vaccinated areas.

The average number of medical doctors per 1,000 in low-vaccinated counties was 0.19 (95% confidence interval [CI], 0.18 to 0.20) compared to 0.81 (0.76 to 0.85) in high-vaccinated ones.

While most research has focused on vaccine hesitancy as being a lead cause of regional vaccine disparities in the United States, this study showed lack of healthcare coverage also contributed to gaps between urban and rural Americans.

Disruption to health services was felt most acutely in rural areas, and people in underserved communities were as much as 34% less likely to be vaccinated against COVID-19. Nevada, Montana, North Dakota, South Dakota, and Nebraska had the lowest vaccination rates.

"Many counties, especially those in rural areas, experienced significant disruptions in health care, including the distribution of the COVID-19 vaccine itself," said study co-author Neil MacKinnon, PhD, provost for Augusta University in Georgia, in a press release.

Liver drug unproven for COVID prevention in high demand in China

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In anticipation of COVID-19 surges in China after last week's easing of public health restrictions, the demand for the generic liver drug ursodeoxycholic acid (UDCA) has risen dramatically, but manufacturers say they can't keep up, and experts warn about the limited nature of the study fueling the demand, Scrip reports.

UDCA is used for the treatment of gallstones and for liver diseases involving a slowing or blockage of bile from the liver (eg, primary biliary cirrhosis).

The skyrocketing demand was triggered by a Dec 5 Nature study by researchers at the University of Cambridge in the United Kingdom and the Berlin Institute of Health at Charite in Germany. The researchers concluded that UDCA reduces signaling from the farnesoid X receptor (FXR), which they said reduced angiotensin converting enzyme 2 (ACE2) expression in human and animal tissues. ACE2 facilitates entry of SARS-CoV-2 into human cells.

"We identify a novel function of FXR in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the road for future clinical trials," the researchers wrote.

'A hotly pursued magic drug'

Scrip said the study "elicited great interest in China, particularly among those not vaccinated at all or fully jabbed and those worrying domestic vaccines may not provide effective protection. Literally overnight, UDCA became a hotly-pursued 'magic drug.'"

As a result, some physicians in China are recommending UDCA to prevent infection in high-risk patients, and drug manufacturers Xuantai Pharma and New China Pharma saw share prices jump by 53% to 69%, respectively, last week.

But experts have noted that the study was very limited and didn't evaluate UDCA efficacy. The manufacturers have also expressed caution, with one saying that it can't meet the demand and another saying it hasn't conducted studies on the drug's mechanism of action and that it isn't approved for COVID-19.

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