According to the latest weekly update from the Centers for Disease Control and Prevention (CDC), COVID-19, seasonal influenza, and respiratory syncytial virus (RSV) activity continue to increase across the country, with COVID wastewater detections reaching high levels. 

COVID-19 is still causing a low number of people to seek emergency department care, but numbers are increasing. RSV and flu are also increasing. 

We predict COVID-19 illness will continue to increase in the coming weeks as it usually does in the winter.

"We predict COVID-19 illness will continue to increase in the coming weeks as it usually does in the winter," the CDC said. "COVID-19 activity is increasing in most areas of the country, with high COVID-19 wastewater levels and increasing emergency department visits and laboratory percent positivity.”

RSV activity remains high, with pediatric hospitalizations increasing across most of the country, the CDC said. 

Flu positivity up 12%

Though hospital visits for flu are still moderate, flu positivity increased by 12% in the week ending on December 21. Influenza A, H1N1 and H3N2, were the predominant viruses reported.

Of note, five pediatric deaths associated with seasonal influenza virus infection were reported this week, bringing the 2024-2025 season total to nine pediatric deaths.

“CDC estimates that there have been at least 3.1 million illnesses, 37,000 hospitalizations, and 1,500 deaths from flu so far this season,” the CDC said.

The addition of macrolides for empiric treatment of patients hospitalized with moderate and high-severity community-acquired pneumonia (CAP) was not associated with improved clinical outcomes, according to a population-level study published this week in the Journal of Infectious Diseases.

Using electronic medical record data from 8,872 adults who were hospitalized with CAP in Oxfordshire, England, from January 1, 2016 through March, 19, 2024, and received initial treatment with amoxicillin or co-amoxiclav, researchers from the University of Oxford examined the effect of adjunctive macrolides on 30-day all-cause mortality, time to hospital discharge, and changes in Sequential Organ Failure Assessment (SOFA) score. While guidelines from the British Thoracic Society and the National Institute for Health and Care Excellence recommend combining macrolides with beta-lactam antibiotics for moderate and high-severity pneumonia to provide coverage of atypical pathogens, existing studies have yielded conflicting evidence on efficacy.

Benefits should be weighed against risk of resistance, side effects

Among 3,239 (36.5%) and 5,633 (63.5%) patients who received baseline amoxicillin or co-amoxiclav, 606 (18.7%) and 1,821 (32.3%) received additional macrolide antibiotics, respectively. After adjustments using inverse probability treatment weighting to address confounding by baseline severity, the researchers found no evidence of an association between the use of additional macrolides and 30-day mortality, with marginal odds ratios of 1.05 (95% confidence interval [CI], 0.75 to 1.47) for amoxicillin with versus without a macrolide and 1.12 (95% CI, 0.93 to 1.34) for co-amoxiclav with versus without a macrolide.

There was also no evidence that the addition of macrolides produced differences in time to discharge among those receiving baseline amoxicillin (restricted mean days lost +1.76 [-1.66 to +5.19]) or co-amoxiclav (+0.44 [-1.63 to +2.51]) or that macrolide use was associated with SOFA score decreases (marginal difference with amoxicillin +0.03 [- 0.19 to +0.25]; co-amoxiclav -0.06 [-0.19 to +0.06]). The results were consistent across varying levels of CAP severity.

The researchers also noted that atypical pathogens were rarely identified.

"Our findings suggest that the benefits of empirical macrolide therapy should be weighed against the risk of resistance and side-effects," they wrote.

New chronic wasting disease (CWD) detections were reported this week in Wyoming and Alabama.

In Wyoming, officials with the Wyoming Game and Fish Department confirmed the presence of CWD in a dead cow elk from Elk Hunt Area 84, which is located in the Jackson region in the northwest part of the state. The department said the area has no surrounding CWD-positive elk areas, but its corresponding deer area (Deer HA 152) has had previous CWD detections.

CWD was first identified in free-ranging mule deer in southeastern Wyoming in 1985 and is now found in deer and elk across most of the state. The disease is caused by misfolded infectious proteins called prions, which are extremely resilient and can persist in the environment for years. CWD can spread from animal to animal and through environmental contamination.

Alabama reports ninth CWD case

The CWD detection in Alabama was in a white-tailed deer harvested by a hunter in Colbert County in the northwest part of the state, according to an update from the Alabama Department of Conservation and Natural Resources (ADCNR). It’s the first case of CWD detected in Colbert County and brings the total number of CWD positive detections in the state to nine.

ADCNR officials say the detection has resulted in an expansion of the state's CWD management zone to include all of Colbert, Lauderdale, and Franklin counties.

"I would like to thank our hunters for submitting their harvest samples for testing," ADCNR Commissioner Chris Blankenship said in a news release. "They are our most important partners in the management of this disease in Alabama."

While no human CWD cases have been reported, the Centers for Disease Control and Prevention and the World Health Organization advise against eating meat from sick cervids and urge taking precautions when handling carcasses. 

• The US Food and Drug Administration has upgraded a voluntary recall of organic, pasture-raised eggs sold by Costco stores to Class I, the agency's highest risk level. The eggs, sold under Costco's Kirkland Signature brand, were recalled by Handsome Brook Farms of New York on November 26 because of possible contamination with Salmonella. The eggs were distributed to 25 Costco stores in Alabama, Georgia, North Carolina, South Carolina, and Tennessee beginning November 22, 2024, and have a Use By Date of January 5, 2025. The FDA classifies a recall as Class I when there is "a reasonable probability that the use of, or exposure to, a violative product will cause serious adverse health consequences or death." 
• Health authorities in Kosovo have confirmed the country's first mpox case, according to media reports. Citing a statement from Kosovo's Institute of Public Health, Reuters reports that the case-patient is a 30-year-old man who recently returned from an unidentified West African country and was hospitalized on December 24 after exhibiting fever, chills, and skin changes on his face and hands. The institute said health officials have traced all contacts of the patient and shared recommendations for infection control and prevention.
• Two children in Pakistan were diagnosed as having polio this week, according to Pakistani news site Geo News. The cases, which were reported in Sindh and Khyber Pakhtunkhwa provinces, bring the polio-endemic country's tally for the year to 67. The cases come amid efforts by Pakistani health officials to inoculate 44 million children across the country. In other polio news, Australian health officials revealed this week that routine wastewater testing in Melbourne detected the virus earlier this month. The Victoria Department of Public Health said in a news release that circulating vaccine-derived poliovirus type 2 was detected on December 2 and was likely linked to a person who received a live polio vaccine overseas and has continued to shed the virus since arriving in the country.