Introduction
Viral blips (VB) are transient fluctuations of plasma HIV RNA values
above the detection limit occurring in people with HIV (PWH) who are
receiving effective antiretroviral therapy (ART). Not an infrequent
event, occurring in at least one-quarter of patients on stable ART with
undetectable viral loads (VL), their clinical significance is still a
matter of debate, with some studies linking VB with viral failure. The
pathophysiology of this phenomenon is complex and has not been clearly
elucidated, but research has associated VB with vaccinations. Indeed,
vaccines are immunostimulatory agents by definition and it has been
postulated that they can induce a generalized inflammatory response with
cytokine production, activating bystander cells harbouring latent HIV
and thus leading to HIV reactivation and virion production.
We have recently described the case of a PWH who, having previously
achieved stable viral suppression, experienced a VB after receiving a
dose of COVID-19 vaccine, despite strict adherence to ART and plasma
drug levels within the therapeutic range. Similar findings have been
provided by Levy et al. and Milano et al., who reported 3/143 (2.1%)
and 20/228 (8.9%) episodes after the second shot of COVID-19 vaccine in
their cohort of PWH, respectively. To better understand the real
incidence of VB among PWH vaccinated against COVID-19 and evaluate the
variables associated with this phenomenon we designed this retrospective
cohort study, in which we compared the occurrence of VB in the 12 months
after the first vaccine shot with those recorded in the 12 months
before.