US respiratory virus activity holds steady at low levels

News brief

Acute respiratory illness levels remained low in the United States for the week ending November 23, with COVID levels remaining low and stable for most areas and flu activity continuing to rise slightly among children, the US Centers for Disease Control and Prevention (CDC) said today in its latest weekly updates.

flu vaccination — *Direct Relief, Mark Perlstein / Flickr cc*

For COVID, two early indicators—emergency department (ED) visits and wastewater detections—remained low. Wastewater SARS-CoV-2 detections are highest in the Midwest. However, tracking from WastewaterSCAN, a national wastewater monitoring system based at Stanford University in partnership with Emory University, shows SARS-CoV-2 detections at the high category, with medium concentrations and an upward trend over the past 3 weeks, with the highest levels in the Midwest.

In its latest FluView update, the CDC said though activity remains low, outpatient visits for flulike illness rose a bit to 3%, as the percentage of test positivity remained stable following a slight upward trend over the past several weeks.

Roughly equal proportions of H3N2, H1N1

Most flu detections involve influenza A, and, of influenza A viruses subtyped at public health laboratories, roughly half were the 2009 H1N1 strain and half were H3N2.

No new pediatric flu deaths were reported in the most recent reporting week, keeping the new season's total at two. The CDC received one more report of a pediatric flu death that occurred in January during the 2023-24 season, boosting that total to 206.

The CDC this week is marking the annual observance of National Influenza Vaccination Week to remind people that there's still time for everyone ages 6 months and older to be vaccinated against flu this season.

Meanwhile, the nation's respiratory syncytial virus (RSV) activity remains elevated and continues to rise in the southern, central, and eastern regions, especially in children. ED visits for RSV are at the moderate level and are rising.

New 68-case Salmonella outbreak linked to cucumbers from Mexico

News brief

Stephanie Soucheray, MA

Federal health officials have announced a Salmonella outbreak tied to cucumbers imported from Mexico that has sickened 68 people across 19 states.

SunFed Produce, LLC, has issued a voluntary recall for the vegetables sold from October 12, 2024, to November 26, 2024. The Food and Drug Administration (FDA) said the American slicer cucumbers were packaged in bulk cardboard containers labeled with the SunFed label in a generic white box or black plastic crate with a sticker that reads, "Agrotato, S.A. de C.V."

"FDA is working with SunFed Produce, LLC and their direct customers to determine if additional downstream customer recalls are necessary," the agency said.

According to the Centers for Disease Control and Prevention (CDC), as of November 26, 2024, a total of 68 people infected with the outbreak strain of Salmonella have been reported in 19 states. Illness-onset dates range from October 12, 2024, to November 16, 2024.

18 people hospitalized

Of the 50 people for whom information is available, 18 have been hospitalized. No deaths have been reported. Of 33 people interviewed by health officials, 27 (82%) reported eating cucumbers in the days prior to illness.

Montana has reported the most cases, with 16. Colorado follows with 8 and Oregon with 7. Texas has 5 cases and South Dakota has 4. The median age of those sickened is 27, and 66% are females.

CDC and states identified six illness sub-clusters at two assisted living facilities, three school districts, and one restaurant.

"CDC and states identified six illness sub-clusters at two assisted living facilities, three school districts, and one restaurant," the CDC said in its outbreak report. "An illness sub-cluster is a group of unrelated people who all ate at the same location or event, such as a restaurant, long-term care facility, or school. Cucumbers were served at these six sub-cluster locations."

UK reports fifth imported mpox case

News brief

Stephanie Soucheray, MA

The United Kingdom (UK) has reported its fifth clade 1b mpox case, which isn't part of the family cluster involving the previous four cases. The new case is in a patient from Leeds who had recently traveled to Uganda.

This case has no links to the previous cases identified.

"This is the fifth case of Clade Ib mpox confirmed in England in recent weeks. This case has no links to the previous cases identified. All 4 previous cases were from the same household and all have now fully recovered," said the UK Health Security Agency in a report.

Clade 1b has been causing mpox outbreaks across Africa, especially in the Democratic Republic of the Congo (DRC). It has also been detected in the UK, Canada, Sweden, India, Thailand, and Germany.

UK health officials said the overall threat to the UK population remains low.

2,680 new cases in Africa

In related news, late last week Africa CDC reported 2,680 new cases in the most recent reporting week, mostly from Burundi, the DRC, and Uganda. Cameroon reported new cases after six weeks, and cases have been reported from a new part of Ivory Coast.

The DRC and Burundi accounted for 96% of new cases. Children under the age of 15 account for 38% of the cases, and men make up 53.3% of cases overall.

Several African nations are now entering their fourth week with no new cases: South Africa, Cameroon, Gabon, Guinea, and Rwanda.

First CWD cases in deer outside of containment zone reported in West Virginia

News brief

Mary Van Beusekom, MS

White-tailed deer — peterichman / Flickr cc

The first cases of chronic wasting disease (CWD) outside of West Virginia's Potomac Highlands and Eastern Panhandle management zone have been discovered in captive white-tailed deer in the north-central part of the state, MetroNews reports.

Kent Leonhardt, West Virginia Commissioner of Agriculture, told the news outlet that the first positive CWD test was documented in September after a number of captive deer on a farm died of epizootic hemorrhagic disease (EHD), which affected deer in many parts of the state this year amid drought. He said the deer likely died of EHD but also had CWD.

The farmer has been very cooperative and we're trying to get a very humane depopulation done so that it doesn't continue to spread, but at the same time we've got to make sure the farmer is properly compensated.

Kent Leonhardt

They were the state's first CWD cases from a captive-deer facility, which has been quarantined. "Right now we believe it has been contained," Leonhardt said. "The farmer has been very cooperative and we're trying to get a very humane depopulation done so that it doesn't continue to spread, but at the same time we've got to make sure the farmer is properly compensated."

One CWD-positive deer from the farm had been transferred to another facility in the state 2 days before its CWD status was known. That facility wasn't quarantined.

West Virginia's CWD containment zone was established more than a decade ago after detections in wild deer.

CWD caused by prions, EHD by virus

Caused by misfolded infectious proteins called prions, CWD is a fatal neurodegenerative disease that affects cervids such as deer, elk, moose, and reindeer. CWD can spread from animal to animal and through environmental contamination. The disease isn't known to infect humans, but authorities advise against eating meat from a sick animal and recommend using precautions when handling carcasses.

EHD is a viral disease transmitted primarily to white-tailed deer by tiny biting flies called midges. The fatal disease can also affect mule deer, pronghorn antelope, and domestic sheep, cows, and goats. It typically causes fever, loss of appetite, weakness, loss of fear of humans, and swelling of the head or neck. Death usually occurs within 8 to 36 hours of symptom onset.