Overall, 305 PLWH were included, 251 male (82.3%) and 54 female (17.7%). The median age was 48 years (IQR 47–51). As all participants are linked to our tertiary care centre, CD4 + T cell counts were checked on a regular basis (every 3–4 months), and current data was available. The median CD4 + T cell count at inclusion into the study was 543/ul (IQR 304–770), CD4 + T cell count was ≥ 200/ul in 297 of the patients (97.4%) and the median CD4-nadir was 260/µl. Of note, 21.3% (65/305) of the participants had initially presented with a CDC classification status C3. The rate of patients holding an immunization card at assessment was 88.5% (270/305). There was no relevant sex-difference, 226 (90.0%) of male PLWH were able to present an immunization card, compared to 44 (81.5%) of female participants (Table 1).
The rates for the seven different vaccinations being recommended by the EACS for PLWH showed a wide range in this survey. For 4 of them, including seasonal Influenza, Hepatitis A (HAV), Hepatitis B (HBV) and Streptococcus pneumoniae, a high vaccination rate was observed. On the other hand, rates for Neisseria meningitidis, Varizella zoster and Human papillomavirus were at the bottom end of the scale. Indeed, none of the participants was vaccinated against HPV and Varizella zoster, though for the latter one, a high percentage of cleared infections has to be mentioned (Table 2).
The overall vaccination rate for seasonal influenza was 76.5% (231/302). 3 participants had to be excluded from the analysis because of an inconclusive vaccination status. As the study period was April to June 2018 we assessed for vaccination during the Influenza season 2017/2018. PLWH older than 60 years showed a higher vaccination rate (83.3%) compared to participants younger than 60 years of age (75.6%) (Fig. 1). A difference between genders could not be observed.
The screening for HAV among our patients detected HAV antibodies in 74.2% (222/299) of cases. Only 9.4% (28/299) of the patients gained immunity after undergoing an HAV-infection, while 64.9% (194/299) of the remaining PLWH developed HAV-antibodies following HAV vaccination (Fig. 2). For 6 participants of the study data were lacking or inconclusive and neither the vaccination status nor an immune status could be obtained.
Hepatitis B, known to be a common co-infection among PLWH, is also included in the EACS vaccination recommendations. In 7 patients data were lacking, so 298 could be included into analysis. 23.5% (70/298) of patients showed markers of past HBV-infection. For most of them, Anti-Hbc- and Anti-Hbs-antibodies could be detected (65/70). 1 participant had cleared an HBV-infection, but lost Anti-Hbc-Ab status, in 3 of the cases anti-Hbs-Ab were not detectable anymore. Only 1 PLWH had gone through an HBV-infection and cleared, but lost anti-Hbc- and anti Hbs-Ab over time. Chronic hepatitis B infection defined as persistent HBsAg > 6 months could be detected in 7.0% (21/298), all were receiving a TDF- or TAF-containing cART. The vaccination rate in the remaining 207 PLWH was 64.3% (133/207) (Fig. 3). All remaining 74 HBV unvaccinated and infection naïve PLWH received a TDF- or TAF-containing cART.
Vaccination against Neisseria meningitidis, which is also part of the EACS vaccination recommendation for PLWH, could be observed in only 9 PLWH(3%). In our evaluation we did not differentiate between the conjugate vaccine which includes protection against A, C W135 and Y subtypes and the split vaccine against subtype B which is most commonly used in Germany.
Most likely following infection with Varizella zoster during childhood PLWH in our study showed sufficient antibody titers except for 3 cases, who were subsequently vaccinated. All PLWH with positive antibody titers had not undergone vaccination. Their antibodies developed through infection and subsequent immune response.
236 PLWH (77.4%) had been vaccinated against Infection with Streptococcus pneumoniae with 138 patients (58.5%) receiving the 13-valent vaccine (Prevenar13®) and the polysaccharide vaccine (Pneumovax® 23) at some later point, but not before 6 months after the initial dose. Another 33 PLWH (11%) were vaccinated by only using the PPV-23 polysaccharide vaccine (Fig. 4).