tetano
Editor, Senior Moderator
Vaccine. 2017 Nov 22. pii: S0264-410X(17)31597-9. doi: 10.1016/j.vaccine.2017.11.033. [Epub ahead of print]
[h=1]Molecular epidemiology of influenza B virus and implications in immunization strategy, Southern Brazil.[/h] Lapinscki B[SUP]1[/SUP], Pereira LA[SUP]1[/SUP], Nogueira MB[SUP]1[/SUP], Vidal LR[SUP]1[/SUP], Riediger I[SUP]2[/SUP], Debur MC[SUP]2[/SUP], Presibella M[SUP]2[/SUP], Raboni SM[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Epidemiological indicators have shown the substantial impact of influenza B (Flu B) on the development of severe acute respiratory infection (SARI) and on mortality rates. In Brazil, the trivalent vaccine, composed of only one Flu B lineage is available. We investigated Flu B infections in clinical samples collected by the epidemiological surveillance service of Paran? State, Brazil, from 2013 to 2016. The Flu B lineages Yamagata- (B/Yam) and Victoria-like (B/Vic) were identified using the qRT-PCR assay, and notification forms were reviewed. Among 379 Flu B positive samples evaluated, 370 (98%) were characterized as B/Yam or B/Vic lineages. Both co-circulated with a frequency of 47% and 53%, respectively. B/Yam infected equally both genders, while B/Vic was more frequent in females (71%). The median age of patients infected by B/Vic (23y; 11-35) was lower than that of patients infected by B/Yam (32y; 12-50). Mismatch between the vaccine and the circulating strain was observed in the 2013 season, with a high number of SARI cases. B/Vic lineage was associated with a larger number of SARI cases (62%), while B/Yam with influenza-like illness (ILI) (61%). Differences were observed in the strains circulating in separate regions of Paran? State. B/Vic was prevalent in the northwestern (67%) and B/Yam in the southeastern region (60%). The unpredictability of Flu B lineage circulation causes a substantial increase in severe disease during epidemics in a vaccine mismatch season. In addition, the differences in the epidemiological profile of the target population of Flu B infections in relation to other respiratory viruses, as well as among the B/Vic and B/Yam lineages may also be associated to an increase in disease burden. These findings have direct consequences on vaccination strategies. Therefore, further molecular epidemiology studies of Flu B in Brazil are required to corroborate these primary results.
[h=4]KEYWORDS:[/h] Influenza B lineages; Influenza vaccine; Respiratory infection surveillance
PMID: 29174679 DOI: 10.1016/j.vaccine.2017.11.033
[h=1]Molecular epidemiology of influenza B virus and implications in immunization strategy, Southern Brazil.[/h] Lapinscki B[SUP]1[/SUP], Pereira LA[SUP]1[/SUP], Nogueira MB[SUP]1[/SUP], Vidal LR[SUP]1[/SUP], Riediger I[SUP]2[/SUP], Debur MC[SUP]2[/SUP], Presibella M[SUP]2[/SUP], Raboni SM[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Epidemiological indicators have shown the substantial impact of influenza B (Flu B) on the development of severe acute respiratory infection (SARI) and on mortality rates. In Brazil, the trivalent vaccine, composed of only one Flu B lineage is available. We investigated Flu B infections in clinical samples collected by the epidemiological surveillance service of Paran? State, Brazil, from 2013 to 2016. The Flu B lineages Yamagata- (B/Yam) and Victoria-like (B/Vic) were identified using the qRT-PCR assay, and notification forms were reviewed. Among 379 Flu B positive samples evaluated, 370 (98%) were characterized as B/Yam or B/Vic lineages. Both co-circulated with a frequency of 47% and 53%, respectively. B/Yam infected equally both genders, while B/Vic was more frequent in females (71%). The median age of patients infected by B/Vic (23y; 11-35) was lower than that of patients infected by B/Yam (32y; 12-50). Mismatch between the vaccine and the circulating strain was observed in the 2013 season, with a high number of SARI cases. B/Vic lineage was associated with a larger number of SARI cases (62%), while B/Yam with influenza-like illness (ILI) (61%). Differences were observed in the strains circulating in separate regions of Paran? State. B/Vic was prevalent in the northwestern (67%) and B/Yam in the southeastern region (60%). The unpredictability of Flu B lineage circulation causes a substantial increase in severe disease during epidemics in a vaccine mismatch season. In addition, the differences in the epidemiological profile of the target population of Flu B infections in relation to other respiratory viruses, as well as among the B/Vic and B/Yam lineages may also be associated to an increase in disease burden. These findings have direct consequences on vaccination strategies. Therefore, further molecular epidemiology studies of Flu B in Brazil are required to corroborate these primary results.
[h=4]KEYWORDS:[/h] Influenza B lineages; Influenza vaccine; Respiratory infection surveillance
PMID: 29174679 DOI: 10.1016/j.vaccine.2017.11.033