FDA working with CMS to look for new clues on flu vaccine protection
US Food and Drug Administration (FDA) Commissioner Scott Gottlieb, MD, today weighed in on steps the FDA it taking to improve the effectiveness of seasonal flu vaccines, which includes collaborating with partners at the Centers for Medicare and Medicaid Services (CMS) to use a large database that includes information on flu vaccines given to 4 million people.
In a statement, he said an analysis of the data is still underway, but it may have some clues on effectiveness of cell-based and egg-based vaccines and may shed light on effectiveness of high-dose and adjuvanted version of the vaccines in seniors, as compared to standard flu vaccine. "What we learn about the differences in efficacy between these different vaccines might reveal information that can inform why overall effectiveness against H3N2 was lagging," Gottlieb said.
One theory is that people may require a higher amount of H3N2 antigen to prompt a better immune response, he said, adding that preliminary CMS data has suggested that cell-based flu vaccine might be somewhat more effective than egg-based vaccine. FDA scientists are combing through the data to see if there are any other reasons for the drop in vaccine effectiveness against H3N2 and are working with scientists inside and outside the government to understand the findings.
Earlier this month, US scientists released interim effectiveness estimates for this season's vaccine, which found that protection against H3N2 was 25%, less than hoped and similar to what some other countries have recently found. The gap in protection has been especially problematic over the past few seasons, and scientists say the issue likely stems from a combination of factors, but especially an egg-adaptation that has been identified in the vaccine strain used to make egg-based vaccines.
The FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) meets on Mar 1 to discuss the World Health Organization's (WHO's) recently announced recommendations for the Northern Hemisphere's 2018-19 flu season.
Feb 26 FDA statement
FDA VRBPAC meeting information
WHO approves Shanchol cholera vaccine
Shantha Biotechnics, an India-based subsidiary of Sanofi, announced today that the WHO has approved its oral cholera vaccine Shanchol, the first of its kind that can be stored and distributed outside of the traditional cold chain, The Economic Times, an English-language paper based in India, reported today.
Shanchol is the second vaccine approved for mass campaigns to prevent and control cholera outbreaks. According to the report, the vaccine can be kept for a single period of up to 14 days at a temperature of up to 40°C just before administration, as long as it hasn't expired and the vaccine vial monitor hasn't reached the discard point.
The WHO prequalified Shanchol in 2011, and since then, 12 million doses have been sent to 25 countries, including the Democratic Republic of Congo, Haiti, Mozambique, and South Sudan.
Feb 26 Economic Times story
PAHO emphasizes yellow fever vaccine for travelers to affected areas
The Pan American Health Organization (PAHO) recently reiterated its recommendation that international travelers be vaccinated against yellow fever at least 10 days before visiting areas where the disease is circulating, according to a Feb 23 statement.
Between Jan 2016 and Jan 2018, seven countries or territories in the Americas have reported yellow fever cases: Bolivia, Brazil, Colombia, Ecuador, French Guiana, Peru, and Suriname. However, most of the illnesses have been reported from Brazil, with cases reported from areas where the disease hasn't been found in several decades, including Sao Paulo and Rio de Janeiro states. The WHO recommends vaccination for international travelers for 21 Brazilian states, and the group is closely monitoring for signs that new areas are at risk.
So far urban transmission via Aedes aegypti mosquitoes has not been documented, and human infections have been linked to two types of forest-dwelling mosquitoes that can spread the disease, Haemagogus and Sabethes. PAHO said travelers to affected countries should also take steps to avoid mosquito bites and seek immediate medical care if they become sick during or after their trips.
Feb 23 PAHO statement