Chikungunya News Today
Latin America, Africa and FDA approves first vaccine
Latin America
According to the latest data from the Pan American Health Organization (PAHO), 346,437 total chikungunya cases were reported, including 184,572 confirmed cases.
In addition, 350 deaths have been reported.
This compares with 262,138 total and 136,130 confirmed chikungunya cases and 87 deaths reported during the same period in 2022.
Brazil has reported the most cases in the Americas with more than 218,000 cases, followed by Paraguay with 123,000-plus cases.
Paraguay accounts for 272 of the chikungunya deaths this year.
Africa
In Africa, 23 new cases and no new deaths of chikungunya were reported from Burkina Faso this past week, according to the Africa CDC.
Cumulatively, 472 cases (237 confirmed; 235 suspected) and no deaths of chikungunya have been reported from five of 70 health districts in Burkina Faso: Pouytenga, Ouagadougou, Zorgho , Koudougou and Bobo.
Including Burkina Faso, Africa has reported 740 cases (498 confirmed; 242 suspected) and no deaths of chikungunya since the beginning of the year— Mali (8;0) and Senegal (220; 0).
Chikungunya vaccine
Today, the U.S. Food and Drug Administration approved Ixchiq, the first chikungunya vaccine. Ixchiq is approved for individuals 18 years of age and older who are at increased risk of exposure to chikungunya virus.
Ixchiq is administered as a single dose by injection into the muscle. It contains a live, weakened version of the chikungunya virus and may cause symptoms in the vaccine recipient similar to those experienced by people who have chikungunya disease.
In addition, although not commonly reported, severe chikungunya-like adverse reactions that prevented daily activity and/or required medical intervention occurred in 1.6% of Ixchiq recipients and none of the placebo recipients. Two recipients with severe chikungunya-like adverse reactions were hospitalized. In addition, some recipients had prolonged chikungunya-like adverse reactions that lasted for at least 30 days. The Prescribing Information includes a warning to inform that the vaccine may cause severe or prolonged chikungunya-like adverse reactions.
The FDA is requiring the company to conduct a postmarketing study to assess the serious risk of severe chikungunya-like adverse reactions following administration of Ixchiq.
The effectiveness of Ixchiq is based on immune response data from a clinical study conducted in the United States in individuals 18 years of age and older. In this study, the immune response of 266 participants who received the vaccine was compared to the immune response of 96 participants who received placebo. The level of antibody evaluated in study participants was based on a level shown to be protective in non-human primates that had received blood from people who had been vaccinated. Almost all vaccine study participants achieved this antibody level.Â
Ixchiq was approved using the Accelerated Approval pathway. Accelerated approval allows the FDA to approve certain products for serious or life-threatening conditions based on evidence of a product’s effectiveness that is reasonably likely to predict clinical benefit. In the FDA’s evaluation of Ixchiq for accelerated approval, evidence of effectiveness is based on immune response data in clinical trial participants. As a condition for approval for Ixchiq, the FDA is requiring confirmatory clinical studies to be conducted to verify clinical benefit.
Chikungunya
Chikungunya is transmitted through the bite of an infected mosquito. Symptoms of chikungunya include fever, joint pain, muscle pain, headache, and rash. Symptoms typically appear 3-7 days after being bitten, but can develop up to 12 days after exposure. Most people recover within a week; however, joint pain can sometimes persist for months.