Babesiosis rates rising steadily in the US

News brief

Rates of babesiosis, a tickborne disease, increased by 9% per year in the United States from 2015 to 2022, according to a study today in Open Forum Infectious Diseases.

The study also found 4 in 10 people with babesiosis were coinfected with another tickborne illness, including Lyme disease.

Babesiosis is caused by the Babesia parasite which is transmitted by black-legged ticks found mostly in the Northeast and Midwest. The infection attacks the red blood cells, and though most people recover after flu-like symptoms, infection can be deadly in the elderly and immune compromised.

To assess the prevalence of the parasite, researchers from the Penn State College of Medicine identified 3,521 individuals who were infected with babesiosis between October 2015 and December 2022 through TriNetX, a large, national database of clinical patient data from over 250 million patients.

Increasing diagnoses in summer months

They found increasing diagnoses made each summer, for an average annual increase of 9%. The prevalence of 1 or more coinfections was 42% (95% confidence interval, 40% to 43%). Among all patients diagnosed with babesiosis, 41% were co-infected with the bacterium responsible for Lyme disease, and 3.7% and 0.3%, respectively, were co-infected with bacteria that cause ehrlichiosis and anaplasmosis.

The authors said the increase in cases was likely due to climate changes, which have led to increasing habitats for black leg ticks.

If you live in areas where babesiosis is endemic, mostly states in the Northeast and the Midwest, take precautions, especially during the summer months

"If you live in areas where babesiosis is endemic, mostly states in the Northeast and the Midwest, take precautions, especially during the summer months," study author Paddy Ssentongo said in a Penn State press release. "Practice tick-bite prevention practices. Wear long-sleeved shirts and pants and light-colored clothes. Use tick repellant and check for ticks after spending time outdoors."

CDC ups travel advisory for Marburg in Rwanda, announces traveler screening

News brief

Lisa Schnirring

As part of the US government’s response to Rwanda’s Marburg virus outbreak, the US Centers for Disease Control and Prevention (CDC) yesterday issued a level 3 travel notice for the country and said next week it will begin screening travelers who have recently been in Rwanda.

Regarding the travel notice, the CDC upped its advice from a level 2 notice (take enhanced precautions) to a level 3, which urges people to reconsider nonessential travel. The CDC said the recommendation applies to all of Rwanda, because Marburg infections have been confirmed in several districts.

The CDC urged anyone traveling to Rwanda to consider getting travel insurance to cover delays, illnesses, or injuries, and to take steps to avoid people experiencing Marburg symptoms, potential animal sources of the virus, and nonessential visits to health facilities in outbreak areas.

Screening begins next week at 3 airports

Meanwhile, traveler screening will begin on October 14 and will apply to people who have been in Rwanda in the past 21 days, which is outer range for the incubation period. The step is part of a strategy to prevent imported cases. Passengers who have been in Rwanda will be rerouted for screening at one of three airports, a CDC spokesman told CBS News. They include Chicago’s O’Hare International Airport, New York City’s John F. Kennedy International Airport, and the Washington, DC Dulles International Airport.

Rwanda’s health ministry has also been screening departing travelers.

In a US Department of Health and Human Services fact sheet, federal officials also detailed the agency's on-the-ground support for Rwanda, which has included scientific support from a CDC field office that has been in Rwanda since 2002 and deployment of CDC senior scientists.

FDA authorizes sale of first home COVID/flu combo test outside of emergency use

News brief

Mary Van Beusekom, MS

Mother testing son for respiratory illness — *tatyana_tomsickova / iStock*

As the country heads into the respiratory illness season, the US Food and Drug Administration (FDA) announced yesterday its marketing authorization of the first over-the-counter (OTC) rapid-antigen COVID-19/flu combination test outside of emergency use authorization.

The Healgen Rapid Check COVID-19/Flu A&B Antigen Test takes 15 minutes to detect proteins from both COVID-19 and influenza A and B in nasal swabs. It joins other OTC COVID-19/flu tests already available under emergency use authorization. The test is designed for use by people aged 14 years or older collecting and testing their own sample or those 2 and older with adult assistance.

Risk of false-negative results

FDA review of data from people with signs and symptoms of COVID-19 and flu showed that the test correctly identified 99% of negative and 92% of positive SARS-CoV-2 samples, 99.9% of negative flu A and B samples, and 92.5% and 90.5% of positive influenza A and B samples, respectively. The FDA and the National Institutes of Health's Independent Test Assessment Program collected the validation data.

People who test negative and continue to have fever, cough, and/or shortness of breath may indeed have COVID-19, flu, or another respiratory disease and should visit their healthcare provider.

The FDA reminded users of the risk of false-negative test results with rapid-antigen tests. People who test negative and continue to have fever, cough, and/or shortness of breath may indeed have COVID-19, flu, or another respiratory disease and should visit their healthcare provider. Those who test positive for COVID-19 or flu should take appropriate precautions to avoid spreading the virus and seek follow-up care.

The agency is also establishing criteria called special controls that define the labeling and performance-testing for these tests, the statement said.

"When met, the special controls, in combination with general controls, provide a reasonable assurance of safety and effectiveness for tests of this type," it said. "This action also creates a new regulatory classification, which means that subsequent devices of the same type with the same intended use may go through the FDA’s less burdensome 510(k) pathway."