More H5N1 avian flu detections have been confirmed in poultry flocks in nine states over the past 2 days, including a massive layer farm in Pennsylvania that has nearly 2 million birds, according to the latest notifications from the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS).

Layer farms have been hard hit in multiple states, and the latest event in Pennsylvania’s Dauphin County will likely add to ongoing egg supply shortages. The virus also struck another commercial farm in Pennsylvania, a broiler facility in Cumberland County that has 30,000 birds.

In Ohio, one of the nations recent hot spots, the virus was confirmed at nine more commercial farms, including six turkey farms, two layer farms, and a layer pullet farm.

Other states reporting events at commercial farms include California (turkeys) and Maryland (broilers). APHIS also confirmed the virus at two live bird markets in New York, one in Queens County and the other in Bronx County.

Five states have new detections in backyard flocks, including Michigan, Arizona, Colorado, Pennsylvania, and Kansas.

Since the outbreaks began in early 2022, the outbreaks have led to the loss of a record 156 million birds across all 50 states and Puerto Rico.

Earlier Nevada dairy herd had original cattle genotype

Following the APHIS’ announcement yesterday of a second H5N1 genotype, D1.1, detected in dairy cattle, a spokesperson from the Nevada Department of Agriculture told CBS News that an earlier detection in December in Nye County involved the earlier genotype, B3.13. However, the four latest detections in Churchill County involved the D1.1 genotype, which is circulating in wild birds and has been linked to two severe human infections. 

The spokesperson said two more Churchill herds are in quarantine, pending USDA lab results, and the symptoms in cows infected with D1.1 are similar to those that were sick with the B3.13 genotype.

In other developments, the APHIS today confirmed two more detections in dairy herds, both from California, raising the national total to 959 and the state’s total to 738.

Today the World Health Organization (WHO) said there are now seven cases of Ebola Sudan in Uganda's capital, Kampala, up from two just a couple days ago. The updated case numbers were presented during a WHO Information Network for Epidemics webinar, according to the infectious disease tracking forum FluTrackers.

The index case-patient was a 32-year-old male nurse who developed symptoms on January 19. He died 10 days later, with tests confirming Ebola Sudan. The second patient in the outbreak is the nurse's wife.

So far 298 contacts of the couple have been identified, with 7 confirmed cases. The WHO said there are two main clusters in the outbreak: a family cluster and a healthcare facility cluster. There are no further details on the healthcare facility cases, but the index patient visited a traditional healer and three separate health clinics before he died in Kampala.

Only the index patient has died, leaving the case-fatality rate (CFR) at 14.3%. 

CDC issues health advisory 

Today the US Centers for Disease Control and Prevention (CDC) issued a Health Alert Network (HAN) advisory on the outbreak—its first since the Trump administration issued a pause on the CDC and other federal agencies. 

CDC is communicating with public health departments, public health and clinical laboratories, and healthcare workers in the United States and educating travelers to raise awareness of this outbreak.

"While there are no direct flights from Uganda to the United States, travelers from or passing through affected areas in Uganda can enter the United States on flights connecting from other countries," the HAN said. "CDC is communicating with public health departments, public health and clinical laboratories, and healthcare workers in the United States and educating travelers to raise awareness of this outbreak."

According to the CDC, previous Ebola Sudan outbreaks have a CFR of about 50%. Uganda last reported an Ebola outbreak in 2022, which included 164 cases and 55 deaths (34% CFR). Currently there are no suspected cases of this outbreak outside of Uganda. 

Data from more than 800 US hospitals show that, despite improvements over the course of the COVID-19 pandemic, antibiotic prescribing for COVID-19 and other viral acute respiratory tract infections (ARTIs) remained higher than it should be, researchers reported this week in Open Forum Infectious Diseases.

The study, led by researchers from the University of Wisconsin-Madison School of Medicine and Public Health, analyzed antibiotic prescribing at 803 US hospitals, focusing specifically on antibiotic prescribed to patients admitted for COVID-19 from March 2020 through December 2023 and patients admitted for non-COVID viral ARTIs from January 2019 through December 2023. While the initial spike in antibiotic prescribing at US hospitals linked to the onset of the COVID-19 pandemic has been well-documented, the researchers wanted to assess the impact of the pandemic on antibiotic usage over time.

Continued need for antimicrobial, diagnostic stewardship

The study included 513,698 hospital encounters for COVID-19 and 106,932 for non-COVID viral ARTIs. In March 2020, antibiotics were prescribed for 82.7% of COVID-19 admissions. The rate of antibiotic prescribing for COVID fell to 30.5% in May 2022, with peaks of 50.8% in July 2021 during the Delta surge and 41.7% in July 2022 during the Omicron surge, then levels decreased to 33.8% in December 2023. For other viral ARTIs, the rate of antibiotic prescribing was 55.8% in January 2019, rose to 64.7% in July 2019, peaked at 68.1% in June 2020, declined to 40% in December 2022, then rose to 58.1% in April 2023.

Overall, 45.8% of COVID-19 admissions and 51.2% of viral ARTI admissions received at least one dose of antibiotic from March 2020 through December 2023.

"The perpetuation of high rates of potentially unnecessary antibiotic prescribing demonstrates a continued need for improved diagnostics, diagnostic stewardship, and antimicrobial stewardship programs to reduce antibiotic overprescribing for viral ARTIs," the study authors wrote. 

"Future work should identify drivers of unnecessary antibiotic prescribing for viral ARTI admissions, implement strategies to promote resiliency in antimicrobial stewardship programs for future moments of operational upheaval, and examine the relationship between COVID-19 antibiotic prescribing patterns and antimicrobial resistance development in hospitals across the U.S."

Three more captive deer in three Louisiana parishes have tested positive for chronic wasting disease (CWD), the Louisiana Department of Wildlife and Fisheries (LDWF) reported yesterday.

Authorities detected the cases in Concordia, St Landry, and Tangipahoa parishes after tracing them back to a CWD-positive deer farm in Jefferson Davis Parish identified in November. Concordia and Tangipahoa parishes abut Mississippi's southern and western borders, and St Landry Parish is in the south-central part of Louisiana.

At this time, the disease has not been detected in the wild population in any of the parishes with CWD positive deer pens and associated trace outs.

"In addition to the recent detections, deer from the CWD positive pens have been traced to permitted pens in 11 other parishes," LDWF said in a news release. "No other positives have been confirmed at this time." The 11 parishes are located throughout the western half of the state.

The department has performed statewide surveillance of wild deer since 2002, with the only CWD case in a free-ranging deer found in Tensas Parish in 2022.

LDWF acknowledged that the three recently identified cases have raised concerns about the fatal neurologic disease spreading further into wild deer, but said, "At this time, the disease has not been detected in the wild population in any of the parishes with CWD positive deer pens and associated trace outs."

Testing recommended in CWD-positive areas

CWD, a disease of cervids such as deer, moose, and elk, is caused by prions, infectious proteins that trigger abnormal folding in normal proteins. Infected animals shed CWD prions in body fluids, which can spread to other cervids through direct contact or the environment. 

Although CWD is not known to infect people, the US Centers for Disease Control and Prevention and the World Health Organization advise against eating infected animals. People who hunt in CWD-positive areas should have their deer tested for the disease before consuming the meat.