Mass Spectrometric Characterization of Narcolepsy-Associated Pandemic 2009 Influenza Vaccines

The onset of narcolepsy, an irreversible sleep disorder, has been associated with 2009 influenza pandemic (pH1N1) infections in China, and with ASO3-adjuvanted pH1N1 vaccinations using Pandemrix in Europe. Intriguingly, however, the increased incidence was only observed following vaccination with Pandemrix but not Arepanrix in Canada. In this study, the mutational burden of actual vaccine lots of Pandemrix (n = 6) and Arepanrix (n = 5) sourced from Canada, and Northern Europe were characterized by mass spectrometry. The four most abundant influenza proteins across both vaccines were nucleoprotein NP, hemagglutinin HA, matrix protein M1, with the exception that Pandemrix harbored a significantly increased proportion of neuraminidase NA (7.5%) as compared to Arepanrix (2.6%). Most significantly, 17 motifs in HA, NP, and M1 harbored mutations, which significantly differed in Pandemrix versus Arepanrix. Among these, a 6-fold higher deamidation of HA146 (p.Asn146Asp) in Arepanrix was found relative to Pandemrix, while NP257 (p.Thr257Ala) and NP424 (p.Thr424Ile) were increased in Pandemrix. DQ0602 binding and tetramer analysis with mutated epitopes were conducted in Pandemrix-vaccinated cases versus controls but were unremarkable. Pandemrix harbored lower mutational burden than Arepanrix, indicating higher similarity to wild-type 2009 pH1N1, which could explain differences in narcolepsy susceptibility amongst the vaccines.

Disease burden and clinical severity of the first pandemic wave of COVID-19 in Wuhan, China

The novel coronavirus disease 2019 (COVID-19) was first reported in Wuhan, China, where the initial wave of intense community transmissions was cut short by interventions. Using multiple data sources, here we estimate the disease burden and clinical severity by age of COVID-19 in Wuhan from December 1, 2019 to March 31, 2020. Our estimates account for the sensitivity of the laboratory assays, prospective community screenings, and healthcare seeking behaviors. Rates of symptomatic cases, medical consultations, hospitalizations and deaths were estimated at 796 (95% CI: 703–977), 489 (472–509), 370 (358–384), and 36.2 (35.0–37.3) per 100,000 persons, respectively. The COVID-19 outbreak in Wuhan had a higher burden than the 2009 influenza pandemic or seasonal influenza in terms of hospitalization and mortality rates, and clinical severity was similar to that of the 1918 influenza pandemic. Our comparison puts the COVID-19 pandemic into context and could be helpful to guide intervention strategies and preparedness for the potential resurgence of COVID-19.

Disease burden and clinical severity of the first pandemic wave of COVID-19 in Wuhan, China

The pandemic of novel coronavirus disease 2019 (COVID-19) began in Wuhan, China, where a first wave of intense community transmission was cut short by interventions. Using multiple data source, we estimated the disease burden and clinical severity of COVID-19 by age in Wuhan from December 1, 2019 to March 31, 2020. We adjusted estimates for sensitivity of laboratory assays and accounted for prospective community screenings and healthcare seeking behaviors. Rates of symptomatic cases, medical consultations, hospitalizations and deaths were estimated at 796 (95%CI: 703-977), 489 (472-509), 370 (358-384), and 36.2 (35.0-37.3) per 100,000 persons, respectively. The COVID-19 outbreak in Wuhan had higher burden than the 2009 influenza pandemic or seasonal influenza, and that clinical severity was similar to that of the 1918 influenza pandemic. Our comparison puts the COVID-19 pandemic into context and could be helpful to guide intervention strategies and preparedness for the potential resurgence of COVID-19.

Mass Spectrometric Characterization of Narcolepsy-Associated Pandemic 2009 Influenza Vaccines

The onset of narcolepsy, an irreversible sleep disorder, has been associated with 2009 influenza pandemic (pH1N1) infections in China, and with ASO3-adjuvanted pH1N1 vaccinations using Pandemrix in Europe. Intriguingly, however, the increased incidence was only observed following vaccination with Pandemrix but not Arepanrix in Canada. In this study, the mutational burden of actual vaccine lots of Pandemrix (n=6) and Arepanrix (n=5) sourced from Canada, and Northern Europe were characterized by mass spectrometry. The four most abundant influenza proteins across both vaccines were nucleoprotein NP, hemagglutinin HA, matrix protein M1, with the exception that Pandemrix harbored a significantly increased proportion of neuraminidase NA (7.5%) as compared to Arepanrix (2.6%). Most significantly, 17 motifs in HA, NP, and M1 harbored mutations, which significantly differed in Pandemrix versus Arepanrix. Among these, a 6-fold higher deamidation of HA146 (N to D) in Arepanrix was found relative to Pandemrix, while NP257 (T to A) and NP424 (T to I) were increased in Pandemrix. DQ0602 binding and tetramer analysis with mutated epitopes were conducted in Pandemrix-vaccinated cases versus controls but were unremarkable. Pandemrix harbored lower mutational burden than Arepanrix, indicating higher similarity to wild-type 2009 pH1N1, which could explain differences in narcolepsy susceptibility amongst the vaccines.

0773 Why Did Pandemrix Trigger Narcolepsy? A Structural Approach

Introduction The 2009 Pandemrix influenza A pH1N1 vaccine has been linked to an increased number of Narcolepsy type I onsets in children across Europe whereas administration of a very similar adjuvanted vaccine, Arepanrix, had little effects in Canada. One possible explanation for the difference may be vaccine composition differences that could modify peptide binding to narcolepsy associated HLA-DQ0602 allele, as viral extracts for these two vaccines used distinct processes in different factories. Other explanations may involve differences in vaccination timing in relation to the pandemic H1N1 infection wave, or other environmental factors. We have previously compared the amino acid sequence of the Hemagglutinin (HA) component of the Pandemrix and the 2010 Arepanrix vaccine, finding possible contributors, but excluding most of these after DQ0602-tetramer analysis of T cell reactivity in narcolepsy versus controls. Methods Mass spectrometric characterization of multiple additional batches of Pandemrix and Arepanrix used during 2009 influenza pandemic vaccination campaign was performed. Results In addition to confirming previously published results such as increased deamidation of hemagglutinin (HA) (146N>D) in Pandemrix (p=2.1e-9), we identified novel differences, including a significant 2-fold post-translation deamidation increase in 277N in Arepanrix versus Pandemrix (p=0.032), together with increased 2-fold glycosylation in the 286-323 positions in Arepanrix (p=0.00036). The 277 N to D/isoD substitution is located in pocket 1 of the binding core of a strong binder NAGSGIIIS, (< 10% rank) for HLA-DQ0602 allele and abolishes epitope binding. The increased glycosylation in Arepanrix occurs in the immediate flanking area of the same 277N epitope and could also reduce DQ0602 presentation of the same epitope through differential binding and/or proteolysis of HA in this region of the molecules. As CD4 T cells recognizing this epitope have been reported to be significantly increased in narcolepsy versus DQ0602 controls, with possible mimicry with homologous hypocretin sequence. Conclusion These changes could explain why Arepanrix was less narcolepsy inducing. Confirmatory studies, as well as studies of all novel changes observed, are ongoing, but this is a promising result. Support Wake Up Narcolepsy

Global dynamic spatiotemporal pattern of seasonal influenza since 2009 influenza pandemic

Background Understanding the global spatiotemporal pattern of seasonal influenza is essential for influenza control and prevention. Available data on the updated global spatiotemporal pattern of seasonal influenza are scarce. This study aimed to assess the spatiotemporal pattern of seasonal influenza after the 2009 influenza pandemic. Methods Weekly influenza surveillance data in 86 countries from 2010 to 2017 were obtained from FluNet. First, the proportion of influenza A in total influenza viruses (PA) was calculated. Second, weekly numbers of influenza positive virus (A and B) were divided by the total number of samples processed to get weekly positive rates of influenza A (RWA) and influenza B (RWB). Third, the average positive rates of influenza A (RA) and influenza B (RB) for each country were calculated by averaging RWA, and RWB of 52 weeks. A Kruskal-Wallis test was conducted to examine if the year-to-year change in PA in all countries were significant, and a universal kriging method with linear semivariogram model was used to extrapolate RA and RB in all countries. Results PA ranged from 0.43 in Zambia to 0.98 in Belarus, and PA in countries with higher income was greater than those countries with lower income. The spatial patterns of high RB were the highest in sub-Saharan Africa, Asia-Pacific region and South America. RWA peaked in early weeks in temperate countries, and the peak of RWB occurred a bit later. There were some temperate countries with non-distinct influenza seasonality (e.g., Mauritius and Maldives) and some tropical/subtropical countries with distinct influenza seasonality (e.g., Chile and South Africa). Conclusions Influenza seasonality is not predictable in some temperate countries, and it is distinct in Chile, Argentina and South Africa, implying that the optimal timing for influenza vaccination needs to be chosen with caution in these unpredictable countries.