The Centers for Disease Control and Prevention regularly issues health advisories, testing guidance, and Advisory Committee on Immunization Practices recommendations to inform clinical decision-making. The following 10-item framework summarizes recent updates with potential implications for patient evaluation, prevention, and public health reporting across a variety of care settings.

1. Medetomidine Alert — The Centers for Disease Control and Prevention (CDC) issued a joint Health Advisory with the White House Office of National Drug Control Policy after reports of increasing detection of medetomidine in the US illegal drug supply. The agency noted that exposure may result in profound sedation, bradycardia, and hypotension as well as severe withdrawal requiring emergency or intensive care. The CDC advised clinicians to consider medetomidine exposure in patients with suspected opioid overdose who have prolonged sedation following naloxone administration, consult poison control or a toxicologist when appropriate, and report unusual cases to public health authorities.

2. Hantavirus Testing Update — The CDC issued a Health Update outlining diagnostic testing resources among patients with suspected hantavirus infection, including Andes virus following an outbreak linked to a cruise ship. As of May 18, the CDC reported no confirmed US cases associated with the outbreak and said the overall public risk remains extremely low. The agency advised clinicians to consider Andes virus infection in symptomatic patients who were aboard the cruise ship or had direct contact with individuals associated with the outbreak, report suspected cases to their health department, and consult the CDC regarding diagnostic testing.

3. Measles Outbreak Advisory — The CDC issued a Health Advisory regarding an expanding measles outbreak in Texas and New Mexico and provided recommendations ahead of the summer travel season. As of March 7, 2025, the two states had reported 208 confirmed outbreak-associated cases and two deaths. The CDC advised clinicians to consider measles in patients with compatible symptoms and relevant travel or exposure history; promptly isolate suspected cases; notify their health department; and verify measles, mumps, and rubella vaccination status in eligible patients.

4. Accelerated Influenza A Subtyping Advisory — The CDC issued a Health Advisory recommending expedited subtyping of influenza A–positive specimens in hospitalized patients amid sporadic human infections with avian influenza A(H5N1) and high seasonal influenza activity. The agency advised clinicians to test patients hospitalized with suspected influenza, obtain influenza A subtyping within 24 hours of admission when appropriate, initiate antiviral treatment without waiting for test results, and promptly notify public health authorities of suspected or confirmed avian influenza A(H5N1) cases.

5. Seasonal Influenza Vaccine Recommendations — The CDC published updated Advisory Committee on Immunization Practices (ACIP) recommendations for the 2025 to 2026 influenza season. The Morbidity and Mortality Weekly Report continued to recommend annual influenza vaccination for patients aged 6 months and older without a contraindication and summarized several updates, including revised vaccine composition, expanded age indications for select vaccines, availability of self- or caregiver-administered FluMist among eligible patients, and a recommendation to use only single-dose influenza vaccines that do not contain thimerosal as a preservative in pediatric, pregnant, and adult patients.

6. Expanded Pneumococcal Vaccine Recommendations — The CDC published updated ACIP recommendations expanding age-based pneumococcal conjugate vaccine (PCV) use to adults aged 50 years and older who have not previously received the vaccine or whose vaccination history is unknown. The updated guidance also stated that recommendations among patients aged 19 to 49 years with risk conditions and for adults previously vaccinated with PCV13 remain unchanged.

7. New World Screwworm Advisory — The CDC issued a Health Advisory after New World screwworm cases were identified in animals in the Mexican state of Tamaulipas, which borders Texas. As of January 20, 2026, the agency reported no outbreak-related infestations in humans or animals in the United States and said the advisory was intended to increase awareness and provide guidance for case identification, reporting, specimen collection, diagnosis, and treatment. The CDC advised clinicians to consider New World screwworm in patients with compatible clinical findings and recent travel to affected areas, promptly report suspected cases to their health department, and coordinate confirmatory testing with the CDC.

8. Pentavalent Meningococcal Vaccine Recommendations — The CDC published updated ACIP recommendations for use of the pentavalent meningococcal vaccine in patients aged 10 years and older. The agency stated that the vaccine may be used when both quadrivalent meningococcal and serogroup B meningococcal vaccines are indicated during the same visit, including among healthy patients aged 16 to 23 years when serogroup B meningococcal vaccination is chosen through shared clinical decision-making and in patients at increased risk for meningococcal disease.

9. Infant RSV Prevention Recommendations — The CDC published updated ACIP recommendations for prevention of respiratory syncytial virus (RSV)-associated lower respiratory tract infection in infants. The guidance added clesrovimab as an alternative to nirsevimab for infants younger than 8 months entering their first RSV season who are not protected through maternal RSV vaccination. The CDC continued to recommend that all infants receive protection through maternal RSV vaccination during pregnancy or a long-acting RSV monoclonal antibody, with product selection guided by caregiver preference, product availability, and when protection will be needed during the infant's first RSV season.

10.  Chikungunya Vaccine Recommendations — The CDC published updated guidance for health care providers on the use of the virus-like particle chikungunya vaccine, which is licensed among patients aged 12 years and older. The guidance recommends vaccination for travelers visiting areas experiencing a chikungunya outbreak and for laboratory workers with potential occupational exposure to the virus. The CDC also stated that vaccination may be considered in travelers planning extended stays in destinations with an elevated risk of chikungunya virus transmission.

Source: CDC, Morbidity and Mortality Weekly Report