LOS ANGELES, Nov. 28 (Xinhua) -- Over 11,200 patients in the United States were hospitalized with flu in the latest week, the highest rate in the same period of time since 2010, according to data released Monday by the U.S. Centers for Disease Control and Prevention (CDC).

 

Seasonal influenza activity is elevated across the country, said the CDC.

 

Five flu-associated pediatric deaths were reported in the week ending Nov. 19. A total of 12 pediatric flu deaths have been reported so far this season, according to the CDC.

 

The CDC estimates that so far this season there have been at least 6.2 million flu illnesses, 53,000 hospitalizations and 2,900 deaths from flu.

 

Of influenza A viruses detected and subtyped this season, 78 percent have been influenza A (H3N2) and 22 percent have been influenza A (H1N1), according to the CDC.

 

Thanksgiving holiday gatherings have amped up the spread of viruses such as flu, coronavirus and respiratory syncytial virus (RSV). RSV and flu are both at high levels for this time of year.

 

"We have seen, in some regions, RSV numbers starting to trend downward. Flu numbers are still on the rise. And we are concerned that after holiday gathering, lots of people coming together, that we may see increases in COVID-19 cases as well," said CDC Director Rochelle Walensky.

 

U.S. top infectious diseases expert Anthony S. Fauci warned RSV could become public health emergency in the United States.

 

"It is if in fact, which in some regions of the country, we're seeing that the hospital system for pediatrics are at the point of almost being overwhelmed," Fauci told CBS News on Sunday.

 

The CDC said an annual flu vaccine is the best way to protect against flu. Vaccination helps prevent infection and can also prevent serious outcomes.

 

The CDC recommends that everyone ages 6 months and older get a flu vaccine annually.

 

For a half-century, scientists have been trying to develop a vaccine that would protect against the most dangerous flu viruses.

 

Now researchers at the University of Pennsylvania are doing research on experimental flu shot aims to target 20 influenza viruses in a single vaccine.

 

Seasonal influenza vaccines offer little protection against pandemic influenza virus strains. It is difficult to create effective prepandemic vaccines because it is uncertain which influenza virus subtype will cause the next pandemic, according to a paper published by the researchers in Science magazine.

 

The researchers developed a nucleoside-modified messenger RNA (mRNA)-lipid nanoparticle vaccine encoding hemagglutinin antigens from all 20 known influenza A virus subtypes and influenza B virus lineages.

 

This multivalent vaccine elicited high levels of cross-reactive and subtype-specific antibodies in mice and ferrets that reacted to all 20 encoded antigens, according to the research.