Probiotics can boost effectiveness of flu shots

Probiotics can boost effectiveness of flu shots

Preventing flu not only saves misery – it saves lives, especially in the most vulnerable populations like children and the elderly.

However, even vaccination is not guaranteed to prevent you from catching the flu.

Making a vaccine takes time and vaccine makers don’t know until the flu season hits exactly what strain they are trying to combat. Moreover, viruses mutate quickly.   As in the previous 2016-17 season, the effectiveness of the flu shot in the 2017-18 winter seems quite poor.

Aussie flu – H3N2

The predominant 2018 flu virus (up to January 2018) is Influenza A (H3N2) or ‘Aussie flu’ – a more serious strain than usual. The last time we encountered that strain there were more flu-related deaths than average.

“H3N2 is a bad virus,” is the verdict of Daniel Jernigan, the director of the US Centers of Disease Control influenza division.

Effectiveness also depends on individual immune response

But there is another reason why the vaccine may not work well – the individual’s immune response isn’t strong enough. So, as medics say, the flu vaccine doesn’t ‘stick’.

However, there is good evidence – from a 2017 meta-analysis of over 12 other studies – that a probiotic supplement can make flu vaccines ‘stick’ or become more effective. It does so by increasing the level of flu antibodies.

Probiotics with prebiotics can help the vaccine "stick"

As the study states:

Participants who took probiotics or prebiotics showed significant improvements in ... sero-protection rate”. 

‘Sero-protection’ was defined as a patient having at least a 4-fold increase in flu virus antibody count.

The study didn’t recommend which strains of probiotics were the most effective – although the strains in the research included Lactobacillus acidophilus, L. casei, L. rhamnosus and Bifidobacterium.

But the indications were that probiotics that also included prebiotics were likely to be more effective. Prebiotics are the complex carbohydrate foods that the ‘friendly bacteria’ live on in the intestine.

How probiotics boost immune cells

Previous research has found that supplementation with Bifidobacterium enhances the effectiveness of two types of immune cells.

The first type are macrophages (meaning "big eaters") – which literally engulf a virus and consume it.

The second are Natural Killer Cells which, as the name implies, kill cells infected by the flu virus and thus prevent them hijacking the machinery of your body’s own cells to create more flu viruses.

In addition, lactobacillus strains are known to enhance a secretion in the saliva called immunoglobulin A, which helps prevent the flu virus from getting inside the body in the first place.

70% of your immune system is in the gut

The preventative effect of probiotics is not surprising because some 70% of your immune system is controlled in the gut. A multi-strain probiotic supplement containing several billion ‘friendly bacteria’ will help boost immune response generally. So studies have found that such probiotics can help prevent upper respiratory tract infections and reduce infection after surgery by 35%

To read more about the role of probiotics in helping prevent flu and in boosting immunity generally see the free report HERE

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  • Nutrients. 2017 Oct 27;9(11). pii: E1175. doi: 10.3390/nu9111175.
    Effect of Probiotics and Prebiotics on Immune Response to Influenza Vaccination in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Lei WT, Shih PC, Liu SJ, Lin CY, Yeh TL.
  • Curr Opin Gastroenterol. 2015 Mar;31(2):153-8. doi: 10.1097/MOG.0000000000000151. Prebiotics, probiotics, synbiotics, and the immune system: experimental data and clinical evidence. Frei R, Akdis M, O'Mahony L.
  • Br J Clin Pharmacol. 2013 Mar;75(3):663-70. doi: 10.1111/j.1365-2125.2012.04404.x. Modulation of vaccine response by concomitant probiotic administration. Maidens C, Childs C, Przemska A, Dayel IB, Yaqoob P.
  • Pediatr Int. 2012 Oct;54(5):682-7. doi: 10.1111/j.1442-200X.2012.03647.x. Epub 2012 Jul 10.
  • Biosci Biotechnol Biochem. 2010;74(5):939-45. Epub 2010 May.
    Randomized controlled trial of probiotics to reduce common cold in schoolchildren. Rerksuppaphol S, Rerksuppaphol L.
  • Effects of Bifidobacterium longum BB536 administration on influenza infection, influenza vaccine antibody titer, and cell-mediated immunity in the elderly. Namba K, Hatano M, Yaeshima T, Takase M, Suzuki K.
  • Meta-analysis
    Effects of perioperative supplementation with pro-/synbiotics on clinical outcomes in surgical patients: A meta-analysis with trial sequential analysis of randomized controlled trials. Xiang-Dong Wu, Meng-Meng Liu, Xi Liang, Ning Hu, Wei Huang