Four countries report more polio cases
Four countries in the Middle East and Africa reported a total of nine new cases this week, according to the latest update from the Global Polio Eradication Initiative (GPEI).
Afghanistan reported one more wild poliovirus type 1 (WPV1) case, in a patient from Kandahar province, rising the country's total for the year to 12. Neighboring Pakistan reported 4 more WPV1 cases, 3 in Balochistan province and 1 in Sindh province, bringing its overall number for the year to 47.
In Africa, two nations—Chad and Ivory Coast—reported more circulating vaccine-derived poliovirus type 2 (cVDPV2) cases. Chad reported two cases, one in Hadjer Lamis province and the other in Logone Occidental province. The country this year has 23 cases related to two outbreaks, one of them linked to an outbreak in Nigeria's Jigawa state. Ivory Coast has one new cVDPV2 case, in a person from Cavally-Guemon province, lifting its total to four in 2020.
The GPEI also said that, because of COVID-19 related supply disruptions, some countries are reporting shortages of bivalent oral polio vaccine for their essential immunization campaigns. It has posted a statement on the situation, which noted that some have tapped into their GPEI-financed vaccine stocks set aside for supplemental immunization activities (SIA).
Study finds added protection of high-dose flu vaccine in elderly
A US Veterans Health Administration (VHA) study published yesterday in Eurosurveillance found that high-dose flu vaccine affords 42% better protection than standard dose against influenza and pneumonia deaths in elderly patients and 27% better against cardiorespiratory deaths.
US researchers linked electronic medical record databases in the VHA and Medicare administrative files to examine the relative vaccine effectiveness (rVE) of high-dose versus standard-dose flu vaccines among VHA-enrolled veterans 65 years or older during the 2012-13 through 2014-15 flu seasons. Among 569,552 person-seasons of observation, 207,574 (36%) were high-dose vaccine recipients and 361,978 (64%) were standard-dose recipients. They were overwhelmingly male (99%) and white (82%).
In pooled estimates across the three seasons, the adjusted rVE for high-dose flu vaccine was 42% (95% confidence interval [CI], 24% to 59%) against flu/pneumonia-associated mortality and 27% (95% CI, 23% to 32%) against cardiorespiratory mortality. When the researchers excluded patients who had high 1-year predicted mortality at baseline to reduce residual confounding, the results dropped a bit, to 36% (95% CI, 10% to 62%) and 25% (95% CI, 12% to 38%), respectively.
May 14 Eurosurveill study