Influenza cases remain high with the start of the first universal human vaccine trial

Thirty-three states and Puerto Rico faced widespread influenza activity for the week ended March 30, the United States Center for Disease Control and Prevention reported on Friday.

Although the flu has not claimed as many lives this year as last year, when more than 80,000 people have died, the death toll remains high. Five children died of influenza-related causes during the week ended March 30, bringing the total number of child deaths for the season to 82; In total, 50,900 deaths from influenza have been recorded this season, according to the CDC. All deaths related to influenza are neither detected nor reported, so the actual number may be higher.

The overall rate of hospitalization was about 56 per 100,000 for the week ended March 30, the highest rate, about 182 per 100,000, among adults over 65, reported l & # 39; agency.

Nationally, strains of the H1N1 virus have been predominant for the entire season. That said, all regions of the country have been dominated by the H3N2 virus in the last three weeks. The H3N2 strain, which was dominant during the 2017-2018 influenza season of last year, generally causes a worsening of flu-like symptoms, leading to more hospitalizations and deaths.

"The yield of the H1N1 virus has dominated up to now or at least the equivalent of the H3N2 virus, which means that the strain causing the most serious disease is currently producing a substantial amount of influenza at the end of the season" Schaffner said.

Finally, the CDC expects that influenza activity will remain high for several weeks, which will put the country back on track for a long season.

"We have a distinct and prolonged influenza season," said Schaffner. He predicts that the next season will result in more illness, hospitalization and death, "because this season will end in April, it will not turn off immediately, and it's a late season."

An experimental vaccine innovates

"It's hard to talk to you because all my fingers and toes are stifled," Schaffner said, joking about his high hopes for the new influenza vaccine that entered clinical trials on Wednesday.

"This is an important first step on the road in several steps leading to the development of a universal flu vaccine," said director of the institute, Anthony Fauci. "We start by trying to protect ourselves from Group 1 influenza A viruses."

Fauci explained that there are about 18 influenza A viruses divided into two groups, one and two. Although a true "universal" vaccine must prove its effectiveness against all strains of the influenza virus, this goal will only be achieved gradually. The new vaccine is therefore the first step in that it aims to effectively counteract a whole group of strains of related influenza viruses.

The reason you have to be vaccinated every year against the flu – and the vaccine itself must be updated every year – is that part of the virus is constantly changing, said Fauci. This phenomenon is called "antigenic drift". To prevent antigenic drift, the new vaccine candidate targets a more consistent part of the influenza strain, an aspect of the virus that varies relatively little from one strain to another.

This first phase of the clinical trial, a human experiment, is underway at the Clinical Center of the National Institutes of Health in Bethesda, Maryland. The goals of this first step are limited, said Fauci: "You want to see if the vaccine is safe – which will probably be – and you want to see if it induces the type of response that would be effective."

The experiment, led by Dr. Grace Chen of the institute's Vaccine Research Center's clinical trial program, will require at least 53 healthy adults under the age of 70 years. Once they have received the influenza vaccine, participants will return for up to 11 follow-up visits over one year to 15 months. Participants will not be exposed to a real flu virus as part of the experiment as scientists look for evidence of immune response, safety and side effects.

Fauci expects that "the usual type of side effects" will be absorbed by the current flu vaccine, such as a sore arm, and does not anticipate any unusual responses. Scientists hope to start reporting results early in 2020.

"If it works, then you go to phase 2, and then to phase 3," Fauci said, explaining that it was more complex human experiences focused on dosing and the ## 147 ## 39, efficiency in the real world. "I am optimistic because we are in the first stage and, ultimately, we are looking for a product really designed to be a universal flu vaccine."

Schaffner said that "to get something like a universal vaccine, which would protect against a variety of different strains, would be a major medical advance." The research is "well thought out" and "now we have to see if it works – how it works."

The flu affects the entire world population, Schaffner said. "If we had a significantly improved vaccine, we could do a lot of good," he said. "We have high hopes."