Respiratory virus activity continued to decline last week, and though COVID-19 indicators continue to decline, estimates of new variant proportions show some notable shifts in SARS-CoV-2, the Centers for Disease Control and Prevention (CDC) said in its weekly updates today.

In its weekly snapshot for flu, COVID-19, and respiratory syncytial virus (RSV), the CDC said no states are reporting high activity. Only one—North Dakota—is reporting moderate activity.

Flu markers continue to tail off

Flu activity continues to decline, with levels below baselines in all but 1 of 10 regions. Region 1, which includes six northeastern states, is at its regional baseline, the CDC said in its weekly FluView update. 

Test positivity declined, and all three seasonal flu viruses continue to circulate, with influenza A making up 62.7% of positive samples at public health laboratories.

Hospitalizations declined, and overall deaths held steady. The CDC received reports of 6 more pediatric flu deaths, raising the season's total to 148. The deaths occurred from November 2023 to early this month. Three were due to influenza A, and three were linked to influenza B.

COVID trends decline, despite rise in FLiRT proportions

In its latest COVID data updates, the CDC reported further declines in its severity markers (hospitalizations and deaths), as well as its early indicators (test positivity and emergency department visits). Wastewater SARS-CoV-2 detections, another early indicator, remained at the minimal level and are at their lowest level since July 2023.

In its variant proportion update today, the CDC reported an ongoing decline in JN.1 variant detections and a steady rise in its spinoffs that have two added spike mutations, nicknamed the FLiRT (F for L at position 456 and R for T at position 346). The most notable rise was for KP.2, which edged above JN.1 and is now at 24.9%. Also, the proportion of another FLiRT subtype, called KP.1.1, rose from 3.1% to 7.5% over the past 2 weeks. 

So far it's not clear if the FLiRT subtypes will trigger another rise in COVID activity.

A new study shows good results in patients with severe COVID-19 for abatacept, an anti-inflammatory immunomodulating drug used to treat psoriatic arthritis, according to findings published yesterday in JAMA Network Open. 

The study was based on results seen among 395 hospitalized patients in the ACTIV-1 IM randomized clinical trial, designed to assess the efficacy of abatacept, which inhibits T-cell activation, reducing multiple inflammatory cytokines. A previous ACTIV-1 trial showed the drug decreased mortality in hospitalized patients with COVID-19, but optimal dosing of the drug based on body weight is still unknown, the authors said. 

"Because increased body weight is a risk factor for severe COVID-19 and is associated with increased abatacept clearance (CL), it is possible that the pharmacokinetics of abatacept may be different in hospitalized patients with COVID-19," the authors said. 

Increased doses linked to recovery 

Abatacept was administered to enrolled participants on day 1 as a single 10-milligram (mg)-per-kilogram intravenous infusion, with a maximum dose of 1,000 mg. At least two blood samples were collected through day 28, with clinical outcomes also assessed over 4 weeks. 

Over the course of the study, 320 patients (81.0%) recovered, 32 (8.1%) did not recover, and 43 (10.9%) died. Every 5,000-unit increase of abatacept was associated with a higher probability of recovery at day 28, with a hazard ratio of 2.63 (95% confidence interval [CI], 1.70 to 4.08).

Overall, participants with higher abatacept exposure had improved outcomes with fewer safety events. Increased levels of the drug were associated with lower odds of a composite safety event at 28 days (odds ratio, 0.46; 95% CI, 0.33 to 0.63).

A higher-dose abatacept regimen would be necessary for most patients to achieve the exposure that resulted in optimal benefit.

"A higher-dose abatacept regimen would be necessary for most patients to achieve the exposure that resulted in optimal benefit derived from this ACTIV-1 IM cohort," the authors concluded. 

The Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) yesterday announced the first detection of two cases of chronic wasting disease (CWD) in Edwards County, and further investigation revealed three more cases.

Two 2-year-old does in a deer-breeding facility tested positive at the Texas A&M Veterinary Medical Diagnostic Laboratory, and the National Veterinary Services Laboratory in Ames, Iowa, confirmed the finding. Subsequent testing of deer penned with the positive deer and other testing yielded three more cases.

CWD has been identified in Texas captive and free-ranging while-tailed deer, mule deer, red deer, and elk since it was first found in the state in 2012.

Infectious prion disease in cervids

Found in deer and other cervids such as moose and elk, the infectious illness is caused by misfolded proteins known as prions. The disease poses an ongoing threat to cervids, given that CWD can spread from animal to animal and through environmental contamination. 

No human cases have been reported, but health officials urge against eating the meat of infected animals and to take precautions when field-dressing or butchering cervids.

The incidence of uveitis in the year after COVID-19 was 17% among nearly 474,000 Korean adults with a history of the inflammatory eye condition, according to a report in JAMA Ophthalmology.

Researchers at the Hanyang University College of Medicine in Seoul mined the Korean National Health Insurance Service and Korea Disease Control and Prevention Agency databases for information on 473,934 patients diagnosed as having uveitis from January 2015 to February 2021. 

The patients had previously had uveitis and had received at least one dose of an mRNA (Pfizer/BioNTech or Moderna) or adenovirus vector–based (AstraZeneca or Johnson & Johnson) COVID-19 vaccine. The average patient age was 58.9 years, 51.3% were women, and none tested positive for COVID-19 during the study period. 

Uveitis is a potentially serious inflammation of the eye's middle layer of tissue that can cause symptoms such as pain, redness, and blurry vision.

Risk was elevated or all 4 vaccines

The incidence of uveitis was 8.6% at 3 months, 12.5% at 6 months, and 16.8% at 1 year. The odds of uveitis were increased among recipients of all four vaccines, including Pfizer (hazard ratio [HR], 1.68), Moderna (HR, 1.51), AstraZeneca (HR, 1.60), and Johnson & Johnson (HR, 2.07). The risk was highest in the first 30 days after vaccination and peaked between the first and second doses (HR, 1.64).

These results emphasize the importance of vigilance and monitoring for uveitis in the context of vaccinations, including COVID-19 vaccinations, particularly in individuals with a history of uveitis.

"Although uveitis following vaccination is rare, our findings support an increased risk after COVID-19 vaccination, particularly in the early postvaccination period," the study authors wrote. "These results emphasize the importance of vigilance and monitoring for uveitis in the context of vaccinations, including COVID-19 vaccinations, particularly in individuals with a history of uveitis."

In a related commentary, Anika Kumar and Nisha Acharya, MD, said it's important to weigh the risk of uveitis with that of remaining unvaccinated against COVID-19. "Indeed, other investigations of postvaccine NIU [noninfectious uveitis] that similarly identified increased risks of NIU after vaccination noted that effect sizes were small and attributable risks were low; thus, the findings should not preclude individuals from receiving a vaccination," they wrote.