Reply letter about: factors associated with poor adherence to vaccination against hepatitis viruses, streptococcus pneumoniae and seasonal influenza in HIV-infected adults

Dear Editor,

We were glad to read the Letter to Editor entitled “Vaccine coverage in PLWH: disparities and potential impact of vaccine hesitancy.” concerning the study of Gagneux-Brunon et al¹ and the relevance and discrepancies with our study. It was really interesting to come up with other authors sharing the same fields of interest and exchange concerns and knowledge on such a major public health issue of PLWH.

Gagneux-Brunon et al further promoted the investigation of factors associated with poor adherence to the suggested vaccination schedule by assessing the patient’s aspect concerning belies and attitudes about vaccines.

We were interested on the distribution of a self-administered questionnaire, which was novel and overcame the burden of limited time interfering with our patients due to heavy workload. We were also surprised by the low vaccine coverage concerning hepatitis A and B vaccines and pneumococcal vaccine, despite sharing same guidelines and costs.

It was also very surprising the fact that France challenges to such an extend the vaccine safety. In Greece approximately same proportions of the general population is against vaccinations for different reasons.

At this point, we need to clarify an issue raised by Gagneux-Brunon et al. In Greece, vaccines are provided free of charge directly by the hospital to PLWH and administered in the Infectious Diseases Unit only to those belonging to social welfare. All other patients should take vaccines in a pharmacy and vaccines are administered by a physician similarly with the French procedures. This facility may improve vaccine coverage but usually patients belonging to social welfare face other socioeconomic impediments.

Indeed as commented by Gagneux-Brunon et al the observed negative impact of the 2010 financial crisis on vaccine didn’t apply to the vaccine coverage against seasonal influenza probably due to the fact that vaccine coverage against seasonal influenza is very low. In Greece there is remarkable low vaccination coverage against seasonal influenza in the general population according to national data from the Hellenic Center for Disease Control & Prevention.³ This phenomenon occurs throughout the last decade despite several influenza outbreaks recorded with high mortality, even among patients not assessed as of high risk. It is also important to mention that in 2014 only 30% of HIV negative adults were vaccinated against seasonal influenza despite meeting several risk factors for infection. Even more surprising is the fact that physicians and health care personnel are poor adherent to the suggested vaccination, with only 24,9% in Tertiary Hospitals and 40,2% in Primary Health Care facilities being immunized against seasonal influenza the time period 2017–2018 according to Hellenic Center for Disease Control & Prevention.¹ These proportions though are higher compared to previous years, due to the prevention campaigns and the outbreaks occurred throughout the country.

We strongly agree that vaccine hesitancy is particularly high for vaccination against seasonal influenza in PLWH and it is really important to clarify the reasons for such an issue. We were interested in the results from the study of Gagneux-Brunon et al which tried to illuminate the causal factors.

Gagneux-Brunon et al gave very important and interesting data on the beliefs and attitudes of PLWH concerning influenza vaccine pointing out the need for efforts and implementation of measures that will increase vaccine coverage in PLWH. Providing targeted information by HIV specialists concerning vaccinations is potentially an effective way of achieving better coverage proportions especially for such a common but simultaneously hazardous infection.

Disclosure of potential conflicts of interest

No potential conflict of interest was reported by the authors.