In its weekly measles update, the Centers for Disease Control and Prevention (CDC) said there are now 1,514 confirmed measles cases in the United States reported this year, with 23 new cases reported in the past week. 

Eighty-six percent of the cases have been part of 40 outbreaks reported to the CDC. Of note, 92% of case-patients are unvaccinated or have unknown vaccination status, 4% have only one measles, mumps, and rubella dose, and 4% were fully vaccinated. 

Twelve percent of cases have required hospitalization, with 29% of those hospitalized aged 19 years or younger. There have been 3 confirmed measles deaths this year. 

Georgia reports 3 new cases

Georgia's health department reported three more measles infections with links to its most recent case; two patients were unvaccinated and one had an unknown vaccination status. Georgia now has 10 confirmed cases in 2025. In 2024, Georgia officials reported six cases.

Finally, as many as 11 babies exposed to measles in Utah were given postexposure prophylaxis (prevention) after four cases were identified in the Bear River Health Department's jurisdiction.

The infants under 1 year of age, who cannot be vaccinated, were administered an immunoglobulin that provides short-term immunity. 

Eleven new Ebola virus cases have been added to the outbreak in the Democratic Republic of the Congo (DRC) in the past week, pushing the case total to 57, including 35 deaths, for a death rate of 61.4%, the World Health Organization (WHO) reported yesterday.

First declared on September 4, the outbreak is still confined to the Bulape Health Zone in Kasai Province. Of the 57 cases, 47 were confirmed, and 10 were probable; of the 35 deaths, 25 were confirmed, and 10 were probable. Five of the confirmed cases were diagnosed in healthcare workers.

Ebola, which spreads through infected blood and other body fluids, typically causes fever and weakness, followed by diarrhea and vomiting.

Children account for 23% of all infections

Infected patients range in age from 0 to 65 years, with those 0 to 9 years making up 23% of all cases. While females account for most cases (61%), their death rate is lower than that of males (56% vs 73%).

No international traffic-related measures are currently warranted.

"The outbreak shows a decreasing trend of cases in the recent week, nevertheless the attention remains high, and response activities are ongoing in all affected health areas including early case detection, isolation, case management, contact tracing, vaccination as well as risk communication and community engagement," the WHO wrote. 

As of September 21, investigators have identified 1,180 contacts for follow-up. Of all contacts, 94 completed 21 days of monitoring, while the rest are still being tracked. Of 26 patients admitted to the Ebola Treatment Centre since the outbreak began, 2 recovered and were released on September 16, 5 died, and 19 are still being treated.

In total, 1,740 people have been vaccinated against Ebola in the Bulape, Bulambae, and Mweka Health Zones in the 9 days since the campaign began.

"No international traffic-related measures are currently warranted," the statement said. Health authorities are reinforcing surveillance at border crossings through activities such as health screening, risk communication, and the integration of border communities in affected areas into early warning systems and the national surveillance network, it added.

Genesee County, Michigan, has become the state's 16th county positive for chronic wasting disease (CWD) in wild deer, the Michigan Department of Natural Resources (DNR) reported today.

Genesee County is in the southeastern part of the state's Lower Peninsula. The case was identified in an emaciated 2.5-year-old doe that was continuously drinking water and walked directly up to the responding conservation officer.

"Genesee County was under focused CWD surveillance in 2022, when approximately 300 deer were tested, with none testing positive," the press release said. "The DNR has continued to test deer that appear sick in Genesee County when possible."

State's first case in wild deer found in 2015

"We appreciate the support and cooperation of the public as they continue to report sick deer so our team can follow up with the necessary testing for confirmation," Brent Rudolph, PhD, DNR deer, elk and moose management specialist, said in the release. 

Since CWD was first detected in Michigan wild deer in 2015, more than 110,000 deer have been tested for the disease in the state. In total, more than 144,000 wild deer have been tested since surveillance began in 2002, with 263 infected deer identified. Since direct hunter submissions of deer to the state's veterinary diagnostic laboratory began in 2020, more than 3,200 samples have yielded 56 additional confirmed cases.

A study of more than 50,000 Canadian seniors diagnosed as having COVID-19 during the first 18 months of the pandemic found that antibiotic use within 7 days of diagnosis was associated with detection of antibiotic resistance organisms, researchers reported today in NEJM Evidence.

The population-wide cohort study, led by researchers with the Ottawa Hospital Research Institute, analyzed data on residents of Ontario aged 66 years and older who had a positive test for SARS-CoV-2 (the virus that causes COVID-19) from January 1, 2020, through June 30, 2021. 

Because antibiotic use in COVID-19 patients was common in the early months of the pandemic in most countries, particularly in older patients, the researchers wanted to evaluate the relationship between peri–COVID-19 antibiotic exposure (within 7 days of index SARS-CoV-2 reporting) and isolation of an antibiotic-resistant organism from a clinical culture within 6 months.

Of the 53,533 eligible patients included in the study, 8,228 (15%) were prescribed a peri–COVID-19 antibiotic, and 1,477 (3%) had a downstream drug-resistant organism identified. Peri–Covid-19 antibiotic use was significantly associated with the presence of any antibiotic-resistant organism (adjusted odds ratio [aOR], 1.24; 95% confidence interval [CI], 1.09 to 1.41) and the presence of gram-negative antibiotic-resistant organisms (aOR, 1.27; 95% CI, 1.11 to 1.46) but not gram-positive antibiotic-resistant organisms (aOR, 1.02; 95% CI, 0.70 to 1.48).

Stewardship in older adults, nursing home residents

Among all individuals who received an antibiotic, the attributable fraction of downstream antibiotic resistance related to peri–Covid-19 antibiotic use was 17% (95% CI, 7% to 26%). Among all individuals with a SARS-CoV-2 diagnosis, the population-attributable fraction of downstream antimicrobial resistance related to peri–Covid-19 antibiotic use was 4% (95% CI, 2% to 7%).

"As antibiotics are often used in the outpatient setting in patients with Covid-19, without clear indications, this study suggests that a substantial burden of antimicrobial resistance in individuals with Covid-19 may have been avoidable," the study authors wrote

They add that the disproportionate impact on older, more vulnerable patients suggests that antimicrobial stewardship programs targeting antibiotic prescribing in older adults and those residing in nursing homes may be beneficial.