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Life Sciences => Physiology & Medicine => Topic started by: tamsinbell on 27/09/2018 17:47:33

Title: Is the shingles vaccine still useful if I've recently had shingles?
Post by: tamsinbell on 27/09/2018 17:47:33
Chris asks:

"Would a vaccination be advisable against Shingles if I have suffered with Shingles for the last 6 months or would my body have built up enough antibodies to prevent another bout of Shingles? Would the Shingles vaccination bring on any mild symptoms of Shingles?"

Do you know? Post an answer!
Title: Re: Is the shingles vaccine still useful if I've recently had shingles?
Post by: evan_au on 28/09/2018 11:25:26
Shingles is the same virus as chicken pox.
- While your immune system quickly clears this virus from your body
- But it can hide out in the nervous system
- The immune system gets weaker as we get older, allowing the virus to break out again

Title: Re: Is the shingles vaccine still useful if I've recently had shingles?
Post by: wolfekeeper on 29/09/2018 02:46:46
Most likely the symptoms you have are not due to a current shingles attack, but is the nerve damage caused by the attack. Your immune system would likely have rebuilt antibodies to it, but a vaccination wouldn't do any harm. In about 85% of cases the pain goes away within a year.
Title: Re: Is the shingles vaccine still useful if I've recently had shingles?
Post by: chris on 01/10/2018 09:51:17
Shingles, also called zoster, is a manifestation of varicella zoster virus (VZV), which is a member of the herpesvirus family. These viruses characteristically infect for life, establishing a latent state from which they can later reactivate multiple times, producing a range of symptoms.

In the case of VZV (chicken pox) the primary infection, which is acquired through the air, produces a rash all over the body; this leads to the infection of sensory nerves that subsequently harbour the viral DNA for the lifetime of the infected individual.

Reactivation occurs from these nerve cells; in response to as-yet undefined signals the viral DNA switches on and begins to assemble new virus particles inside the nerve cell. These are exported down the nerve fibre to the overlying skin where they bud out and infect skin cells, producing infectious blisters.

We don't know why, but unlike the primary disease, the reactivation of chicken pox / VZV remains confined to one patch of skin called a dermatome. This region is supplied by one spinal nerve segment, so it may be that the reactivating virus in some way sends signals to the nearby nerves that all supply one body region and in this way promotes all of them to reactivate together.

The result is a strip of painfully-blistered skin; this is the syndrome referred to as shingles. The lesions are loaded with virus and highly infectious.

The virus is normally held in check - and these manifestations prevented - by the immune system, specifically by white blood cells called T cells. These can recognise when an infected cell begins to express viral chemical signatures that herald a reactivation and can kill the relevant cells. As a result, attempts by the virus to reactivate periodically are stamped out without you even realising.

This sub-clinically recurrent reactivation most probably has the effect of re-priming your immune response, encouraging the T cells to up their game and remain vigilant. It's called the Hope-Simpson model after the man who poposed it.

But as we age, or suffer intercurrent immune suppression or other chronic illnesses, the T cell population and the T cell response can dwindle. This can create a chink in the immunological armour, offering the virus an opportunity to break through and produce a shingles manifestation. Some people seem to be more susceptible to this than others.

Off the back of a reactivation, you will develop a much more profound immunity afterwards, but this will extinguish again over time and your vulnerability will return.

The vaccine contains a heavily-attenuated live VZV strain; injected into the muscle it undergoes limited replication but as it does so it displays the full genetic repertoire of the virus to the immune system, helping to re-kindle a comprehensive immune response. This increases the potency of your surveillance, reducing the likelihood of shingles.

Therefore, having the vaccine will reduce the risk of shingles in the near future; but having shingles will also reduce the risk of another attack of shingles in the near future, but probably not for as long as the vaccine because this will be given when you are well and able to make a more resilient immune response. By definition, when you have a shingles attack you are suffering an immune decrement, so this is not the best time to be making a long-lasting immune response.

I hope that answers the question for you.