New egg-free vaccine gives good protection against matching influenza
Researchers in the US have developed a new influenza vaccine from viruses grown in cell culture rather than the more traditional egg substrate. In theory, vaccines derived from cell cultures should be faster to produce, safer for people allergic to egg, less susceptible to microbial contamination, and free from the vagaries of egg production. But do they work?
This trivalent vaccine induced a robust immune response in young adult volunteers participating in a placebo controlled trial (n=7250). It also prevented 78.5% of influenza caused by antigenically matching strains (95% CI 60.8% to 88.2%), including pandemic influenza A/H1N1. Protection against the other two strains—A/H3N2 and influenza B—was harder to gauge because so few participants had these infections during the 2008-9 season. The 3623 volunteers given the inactivated vaccine reported no serious side effects, although 1571 (43%) found the injection painful and 652 (18%) reported myalgia.
This vaccine looks effective, says a linked comment (doi:10.1016/S0140-6736(11)60174-8), and represents a step forward in vaccine development. Successful control of influenza depends on timing, particularly during pandemics. Cell cultures can accelerate vaccine production, shaving up to 10 weeks off the time it currently takes to produce a vaccine that matches circulating strains. Cell cultures are also better than egg substrates at preserving the structure of viral haemagglutinin, the surface antigen crucial to a successful immune response. This may prove to be their biggest advantage in the end.
CBT and graded exercise are safe and effective treatments for chronic fatigue syndrome
Cognitive behavioural therapy (CBT) and graded exercise are the best treatments for chronic fatigue syndrome, according to a rigorous trial of four different options. Both treatments looked safe when added to specialist medical care and worked better than adaptive pacing therapy or specialist care alone. The 641 participants were treated for six months and followed up for a …