Study ranks relative effectiveness of influenza vaccines in seniors
A study today in the Journal of Infectious Diseases found that egg-based adjuvanted and high-dose (HD) flu vaccines had slightly higher relative vaccine effectiveness (RVE) than egg-based quadrivalent (four-strain) vaccines in nearly 13 million Medicare beneficiaries 65 and older during the 2018-19 flu season.
Led by US Food and Drug Administration (FDA) scientists, the researchers conducted a retrospective cohort study using inverse probability of treatment weighting and Poisson regression to measure RVE in preventing flu-related hospitalizations and emergency department visits.
They found that egg-based adjuvanted vaccines had an RVE of 7.7% (95% confidence interval [CI], 3.9% to 11.4%), and HD vaccines had an RVE of 4.9% (95% CI, 1.7% to 8.1%). Cell-cultured quadrivalent vaccines were not significantly more effective than egg-based quadrivalent vaccines, which had an RVE of 2.5% (95% CI, -2.4% to 7.3%).
"We did not find major effectiveness differences between licensed vaccines used among the elderly during the 2018-19 season," the researchers wrote. "Consistent with prior research, we found that the egg-based adjuvanted and high-dose vaccines were slightly more effective than the egg-based quadrivalent vaccines."
Previous studies in this age-group found a moderately higher RVE for HD influenza vaccines than standard-dose (SD) vaccines during most seasons. Research during the A(H3N2)-dominated 2017-18 season demonstrated a slightly higher RVE for the cell-cultured vaccine than the SD egg-based versions.
Nearly half a million influenza-related hospitalizations and 12,000 to 56,000 deaths occur each year in the United States, most in people 65 and older. Vaccination is the main tool to prevent flu, but its effectiveness in older people has been low during recent seasons, particularly in those in which H3N2 viruses dominated.
Feb 26 J Infect Dis abstract
FDA warns Jimmy John's after recent E coli, Salmonella outbreaks
The FDA last week warned Jimmy John's restaurants after identifying five outbreaks of Shiga toxin–producing Escherichia coli and Salmonella in recent years linked to the sandwich chain's clover sprouts and cucumbers.
In a Feb 21 letter to Jimmy John's President James North, the agency says it detected the outbreaks along with the Centers for Disease Control and Prevention and state and local organizations. "Taken together, these outbreaks, which spanned over the past seven years and impacted no fewer than seventeen states demonstrate the corporate-wide supplier control mechanisms you have in place for receiving fresh produce are inadequate," wrote William Weissinger, program division director of the FDA's Office of Human and Animal Foods.
In the latest outbreak, involving E coli infection, 20 of 22 people sickened in December 2019 reported eating at Jimmy John's restaurants in Iowa. In 2018, 8 of 10 people infected with Salmonella in Illinois and Wisconsin reported eating sprouts at the chain. In 2014, 11 of 19 cases of E coli in six states were traced to five Jimmy John's restaurants. In 2013, 8 people in Colorado were infected with E coli after eating cucumbers at the chain. In 2012, 23 of 29 people in 11 states infected with E coli had sprouts at Jimmy John's.
In May 2012, the letter states, the FDA met with North, who promised to buy clover sprouts from only a single supplier. However, "documents from traceback investigations conducted by FDA, states and local partners demonstrate that in addition to [that supplier's] sprouts, Jimmy John's restaurants are using multiple other sources of sprouts," the letter noted.
The letter acknowledges that Jimmy John's parent company, Inspire Brands, destroyed all sprouts and sanitized its Iowa-based restaurants in December 2019. However, it asks for a list of steps that the company has or will take to prevent the sale of adulterated food at all of its restaurants. The chain has 15 days to file a written response.