Influenza a Greater Concern in the U.S. than Coronavirus


The Centers for Disease Control and Prevention estimate 19 million cases of influenza this season. The exposure to various 2019/2020 influenza strains has resulted in 180,000 hospitalizations and at least 10,000 fatalities among all ages. In contrast to date the U.S. has confirmed 11 cases of Hunan coronavius, all associated with travel from China.

During the present season influenza B has emerged as a predominant serotype. According to Dr. Andi L. Shane, Professor and Chief of Pediatric Infectious Diseases at Emory University School of Medicine, the strain has not been seen in the U.S. for 27 years. This means that those born during this century have had no previous exposure and therefore do not carry antibodies unless vaccinated.

Public health authorities involved in selection of influenza strains for the current season included H1N1 and H3N2 strains of influenza A and an influenza B strain for this season. The B component is only 60 percent homologous with the Victoria-origin virus in circulation. In the 25 to 65 year age group, influenza B is responsible for 43 percent of cases diagnosed, but only 23 percent of the cases in the age group above 65. Fortunately, there are fewer cases of influenza A H3N2 strain, which is responsible for severe complications in the elderly.

Generally, experience and surveillance of circulating strains by the WHO allows the incorporation of appropriate strains into vaccines. Occasionally nature throws a curveball with the emergence and dissemination of either an influenza A or B strain different from those incorporated into the vaccine.

EGG-NEWS has repeatedly advised producers to implement preventive influenza vaccination for all personnel in early fall, especially those in direct contact with flocks. In the unlikely event that a worker infected with a human strain comes into contact with a flock incubating low pathogenicity avian influenza, a recombinant event might take place resulting in the emergence of an avian strain transmissible to humans. Influenza vaccination reduces absenteism and reduces medical costs especially with complications.