Undetectable Viral Load Improves Yellow Fever Immunization

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Load Viral undetectable at the time of immunization improves protection vaccine against yellow feverforpeople c

Viral suppression at the time of immunization is the most important determinant of the long-term immune response to vaccination against yellow fever among people with HIV, Yellow fever virusreport Swiss researchers at ClinicalInfectious Diseases. 

Each person with a non-detectable viral load at the time of the first yellow fever vaccination continued to have a protective response ten years after vaccination, they found.

"People infected with HIV demonstrated good immune response in the short term YELLOW FEVER [yellow fever vaccination that decreased to 75% ten years [post-vaccination]", comment the authors.

"Long-term humanitarian response of patients with HIV-suppressed ART remained vacant for up to 10 years."

the researchers believe that their results have implications for vaccination strategies by writing:

"HIV-infected patients can mount a long protective immune response against YELLOW FEVER if they are vaccinated every 10 years while they are well on the way to ART [antiretroviral therapy] ...

even additional data are available on a single booster after ten years may appear to be adequate to restimulate the vaccine response in case of a new trip to an area where yellow fever is endemic. "

Yellow fever is a serious disease caused by a mosquito and its hemorrhagic form is a very serious condition for which there is no antiviral treatment.

The Yellow Fever Vaccine was considered reactive and protective!

However, there is a highly effective vaccine.

The World Health Organization has issued guidance in 2013 recommending that individuals should receive yellow fever vaccination and boosters every ten years to obtain lifetime protection against the disease.

Many HIV-positive people live or travel to areas where fever is endemic.

The long-term response to vaccination against yellow fever in people with HIV is poorly understood.

Researchers from the Swiss HIV Cohort Study therefore identified 247 people with a first documented vaccination against yellow fever after HIV positive diagnosis.

In general, PRNT was reactive in 46% of people prior to vaccination. A protective immune response was present one, five and ten years after vaccination in 95%, 86% and 75% of people, respectively, was considered as reactive and protective.

Predictors of vaccine response were also examined.

1Vaccination is only recommended for asymptomatic, seropositive individuals with a CD4 cell count above 200 cells /Mm3.This is because a virus-attenuated vaccine and therefore poses significant risk to people with very weak immune systems. Despite this recommendation, the researchers identified eleven individuals who were immunized against afebre while their CD4 cell count was dangerously low.

Overall, PRNT was reactive in 46% of people prior to vaccination. The immune protection protection was present one, five and ten years post-vaccination, in 95%, 86% and 75% of people, respectively.

In people with a suppressed viral load at the time of immunization, the proportion remained consistently high reactive PRNT: 99% at one year, 99% at year five and 100% at year ten.

Having the viral load undetectable at the time of vaccination is a determining factor

An undetectable viral load at the time of vaccination was the only major determinant of the long-term response to the vaccine.

the authors recommend that people with HIV should be vaccinated against fever once their viral load is suppressed, and that they should receive a booster dose after ten years if they remain with HIV suppressed. However, people who were vaccinated while their viral load was detectable should either have delaresposta immune to the measured vaccine or receive a booster dose of vaccination regardless of the elapsed time.

Translated by Cláudio souza do original in Undetectable viral load at time of immunization enhances yellow fever vaccine for people with HIV

Michael Carter

Posted: 24 November 2017

Reviewed by Jackye out trhe Box