Challenges and lessons learned from four years of planning and implementing pharmacovigilance enhancement in sub-Saharan Africa.

Pharmacovigilance (PV) systems in many countries in sub-Saharan Africa (SSA) are not fully functional. The spontaneous adverse events (AE) reporting rate in SSA is lower than in any other region of the world, and healthcare professionals (HCPs) in SSA countries have limited awareness of AE surveillance and reporting procedures. The GSK PV enhancement pilot initiative, in collaboration with PATH and national PV stakeholders, aimed to strengthen passive safety surveillance through a training and mentoring program of HCPs in healthcare facilities in three SSA countries: Malawi, Côte d'Ivoire, and Democratic Republic of Congo (DRC). Project implementation was country-driven, led by the Ministry of Health via the national PV center or department, and was adapted to each country's needs. The implementation phase for each country was scheduled to last 18 months. At project start, low AE reporting rates reflected that awareness of PV practices was very low among HCPs in all three countries, even if a national PV center already existed. Malawi did not have a functional PV system nor a national PV center prior to the start of the initiative. After 18 months of PV training and mentoring of HCPs, passive safety surveillance was enhanced significantly as shown by the increased number of AE reports: from 22 during 2000-2016 to 228 in 18 months to 511 in 30 months in Malawi, and ~ 80% of AE reports from trained healthcare facilities in Côte d'Ivoire. In DRC, project implementation ended after 7 months because of the SARS-CoV-2 pandemic. Main challenges encountered were delayed AE report transmission (1-2 months, due mainly to remoteness of healthcare facilities and complex procedures for transmitting reports to the national PV center), delayed or no causality assessment due to lack of expertise and/or funding, negative perceptions among HCPs toward AE reporting, and difficulties in engaging public health programs with the centralized AE reporting processes. This pilot project has enabled the countries to train more HCPs, increased reporting of AEs and identified KPIs that could be flexibly replicated in each country. Country ownership and empowerment is essential to sustain these improvements and build a stronger AE reporting culture.

Immunogenicity of the Adjuvanted Recombinant Zoster Vaccine: Persistence and Anamnestic Response to Additional Doses Administered 10 Years After Primary Vaccination.

BACKGROUND: The adjuvanted recombinant zoster vaccine (RZV) is highly immunogenic and efficacious in adults ≥50 years of age. We evaluated (1) long-term immunogenicity of an initial 2-dose RZV schedule, by following up adults vaccinated at ≥60 years of age and by modeling, and (2) immunogenicity of 2 additional doses administered 10 years after initial vaccination. METHODS: Persistence of humoral and cell-mediated immune (CMI) responses to 2 initial RZV doses was assessed through 10 years after initial vaccination, and modeled through 20 years using a Piecewise, Power law and Fraser model. The immunogenicity and safety of 2 additional RZV doses were also evaluated. RESULTS: Seventy adults were enrolled. Ten years after initial vaccination, humoral and CMI responses were approximately 6-fold and 3.5-fold, respectively, above those before the initial vaccination levels. Predicted immune persistence through 20 years after initial vaccination was similar across the 3 models. Sixty-two participants (mean age [standard deviation], 82.6 [4.4] years) received ≥1 additional RZV dose. Strong anamnestic humoral and CMI responses were elicited by 1 additional dose, without further increases after a second additional dose. CONCLUSIONS: Immune responses to an initial 2-dose RZV course persisted for many years in older adults. Strong anamnestic immune responses can be induced by additional dosing 10 years after the initial 2-dose course. CLINICAL TRIALS REGISTRATION: NCT02735915.

Adherence to Public Health Measures Mitigates the Risk of COVID-19 Infection in Older Adults: A Community-Based Study.

OBJECTIVE: To assess the prevalence and characteristics of coronavirus disease 2019 (COVID-19) cases during the reopening period in older adults, given that little is known about the prevalence of COVID-19 after the stay-at-home order was lifted in the United States, nor the actual effects of adherence to recommended public health measures (RPHM) on the risk of COVID-19. PATIENTS AND METHODS: This was a cross-sectional study nested in a parent prospective cohort study, which followed a population-based sample of 2325 adults 50 years and older residing in southeast Minnesota to assess the incidence of viral infections. Participants were instructed to self-collect both nasal and oropharyngeal swabs, which were tested by reverse transcription polymerase chain reaction-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) assay between May 8, 2020, and June, 30, 2020. We assessed the prevalence of COVID-19 cases and characteristics of study subjects. RESULTS: A total of 1505 eligible subjects participated in the study whose mean age was 68 years, with 885 (59%) women, 32 (2%) racial/ethnic minorities, and 906 (60%) with high-risk conditions for influenza. The prevalence of other Coronaviridae (human coronavirus [HCoV]-229E, HCoV-NL63, and HCoV-OC43) during the 2019 to 2020 flu season was 109 (7%), and none tested positive for SARS-CoV-2. Almost all participants reported adhering to the RPHM (1,488 [99%] for social distancing, 1,438 [96%] for wearing mask in a public space, 1,476 [98%] for hand hygiene, and 1,441 (96%) for staying home mostly). Eighty-six percent of participants resided in a single-family home. CONCLUSION: We did not identify SARS-COV-2 infection in our study cohort. The combination of participants' behavior in following the RPHM and their living environment may considerably mitigate the risk of COVID-19.

Persistence of immune response to an adjuvanted varicella-zoster virus subunit vaccine for up to year nine in older adults.

BACKGROUND: In adults aged ≥60 years, two doses of the herpes zoster subunit vaccine (HZ/su; 50 µg varicella-zoster virus glycoprotein E [gE] and AS01B Adjuvant System) elicited humoral and cell-mediated immune responses persisting for at least six years. We assessed immunogenicity nine years post-initial vaccination. METHODS: This open extension study (NCT02735915) followed 70 participants who received two HZ/su doses in the initial trial (NCT00434577). Blood samples to assess the cellular (intracellular cytokine staining) and humoral (ELISA) immunity were taken at year nine post-initial vaccination. RESULTS: Participants' mean age at dose 1 was 72.3 years. The fold increases over pre-vaccination in the mean frequency of gE-specific CD4+ T-cells expressing ≥2 activation markers plateaued from year four post-dose 1 until year nine. Anti-gE antibody geometric mean concentrations plateaued and remained above pre-vaccination levels from year four onwards. Immunogenicity at year nine was similar across age strata (60-69, ≥70 years) and confirmed statistical prediction model results using data for up to year six. Further modeling using all data up to year nine predicted immune responses would remain above the pre-vaccination level up to year 15. CONCLUSION: In adults aged ≥60 years, HZ/su-induced immunogenicity remained above pre-vaccination levels for at least nine years post-initial vaccination. SUMMARY: After vaccination with HZ/su, both cell mediated and humoral immunity remained above pre-vaccination levels up to year 9 regardless of age group. Immune responses are predicted to remain above baseline up to 15 years post initial vaccination.