US Centers for Disease Control and Prevention are currently investigating five hospitalizations that have arisen in people who have recently received a vaccine that prevents the disease caused by the Chicungunya virus.
In a notice published on Tuesday on a page with information about the healthcare vaccine, the CDC said that people, all 65 years or older, were hospitalized for cardiac or neurological events after Ixchiq vaccination, the only Chikungya vaccine, which is currently licensed.
CNN turned to CDC for comment.
The Chikungunya virus usually spreads to people through the bite of an infected mosquito. Most adults do not receive the vaccine; It is sometimes recommended for certain passengers at increased risk of being exposed to mosquito disease.
“This topic will be discussed at an upcoming meeting of the Consultative Committee on Immunization Practices (ACIP). Health service providers should discuss the benefits and risks of vaccination with individual passengers based on their age, destination, travel duration and planned activities, “the CDC online announcement said.
Chikungunya’s vaccine and monitoring for adverse events were initially planned to be discussed at an ACIP meeting on Wednesday, according to a project of a meeting program, but this meeting was postponed.
Dr. William Schaffner, an infectious disease expert at the Vanderbilt University Medical Center and ACIP, said the CDC investigation is an example of the system for monitoring the vaccine of the Agency “works perfectly and sends a signal” in the opening of rare events that may deserve a further investigation.
“And of course, CDC and the locals who care for these patients are working on what is perfectly appropriate. This is the way the system needs to work, “Safner said.
“Remember that we are still trying to find out if this is a causal relationship or a coincidence,” he said of an investigation in which he is not directly involved. “Let’s still make no conclusions. That’s why they make the investigation. “
The IxchiQ vaccine, administered as a single muscle shot, contains a lively, weakened version of the Chikungunya virus. The vaccine produced by the biotechnology company Valneva was the first vaccine approved by the US Food and Medicines Administration to prevent disease caused by the Chikungunya virus. Approval in November 2023 is for people 18 years of age or older who are at an increased risk of exposure to the Chikungunya virus.
“It is recommended in a very limited way to travelers who go to countries where there is a current outbreak of infection with the Chikungunya virus, as well as passengers who have been going to countries that have experienced a hearth over the last five years,” Safner said. “And also on laboratories working with the Chicungunya virus in the laboratory.”
CNN turned to Valneva for comment. Prescribing information on vaccine conditions: “Ixchiq vaccination can cause severe or prolonged side effects similar to Chikungunya.”
Chikungunya virus circulates in tropical and subtropical regions. In the United States, it has not been reported topically acquired infections since 2019, according to CDC. But cases and outbreaks have been identified in more than 100 countries in America, Africa, Asia, Europe and the Indian and Pacific.
Symptoms of Chikungunya infections include fever, joint pain, headache, muscle pain, swelling of the joints or rash, according to CDC, and the best way to prevent Chikungunya is to avoid mosquito bites. There are currently no medication for the treatment of Chikungunya, but infected people may feel better with rest, fluids and over-the-counter medications for pain and fever.
In Tuesday, CDC said that common side effects after vaccination occurring in more than 10% of vaccinated people in clinical trials include tenderness, headache, fatigue, muscle pain, joint pain, fever and nausea. Some people have “severe or prolonged adverse reactions of Chikungunya”.
Chikungunya-like reactions included “fever, joint pain, headache, rash, and may also include cardiac and neurological conditions that were serious in two cases,” said Dr. Dan Baruch, Director of the Virology and Vaccines at the Beth Israel Medical Center.
The CDC report has encouraged healthcare providers “reporting all adverse events that can be caused by vaccination of the CDC/FDA (VAERS) vaccine reporting system by submitting an online report or using a PDF form.
“A healthy safety vaccine monitoring system often identifies extremely rare adverse effects of vaccines after approval,” says Baruch, an infectious disease expert who is not involved in the CDC investigation.
When the vaccine was approved in 2023, the FDA notes that its safety was evaluated in two clinical trials conducted in North America, in which about 3,500 adults received a dose of vaccine as a study involving about 1,000 participants who received placebo. Chikungunya’s severe side effects occurred in 1.6% of Ixchiq recipients and none of the placebo recipients, according to FDA.
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