SACRAMENTO, the United States, Feb. 18 (Xinhua) -- Vital data and analyses from the U.S. Centers for Disease Control and Prevention (CDC) about dangerous flu outbreaks have been blocked from release since U.S. President Donald Trump took office, leaving doctors and public health experts struggling to respond to escalating infections, U.S. media quoted health experts as saying.

"Without more information, we are blind," said Sonya Stokes, an emergency room physician in the San Francisco Bay Area, who reported seeing daily surges of patients with flu symptoms, according to KFF Health News. "I need to know if we are dealing with a more virulent strain or a coinfection with another virus that is making my patients sicker and what to look for so that I know if my patients are in danger."

The CDC estimates at least 24 million illnesses, 310,000 hospitalizations, and 13,000 deaths from flu since October, according to KFF Health News.

However, critical information about the severity and spread of both seasonal flu and bird flu strains is being withheld or delayed.

A key CDC analysis suggests flu may be at record levels, with about 7.7 percent of patients visiting clinics and hospitals showing flu-like symptoms in early February -- higher than four previous severe flu seasons, including 2003-2004, when an unusual strain killed in least 153 children.

The communications freeze has also disrupted the CDC's collaboration with international health organizations.

"CDC right now is not reporting influenza data through the WHO global platforms, FluNet and FluID, that they've been providing information on for many, many years," said Maria Van Kerkhove, interim director of epidemic and pandemic preparedness at the World Health Organization.

The situation is particularly concerning given the simultaneous spread of H5N1 bird flu among cattle and farm workers.

CDC data suggest the virus may be spreading undetected, with three out of 150 cattle veterinarians showing antibodies indicating recent infections despite having no symptoms or known exposure to infected animals.

"If the circulating H5 viruses become more transmissible between humans, we are not going to be able to control transmission as the viruses will spread rapidly and often sub-clinically," warned Gregory Gray, an infectious disease epidemiologist at the University of Texas Medical Branch, speaking to the National Public Radio (NPR).

According to Pharmacy Times, the number of confirmed human H5N1 cases reached 68 as of Feb. 14. This included recent hospitalizations in Wyoming and Ohio, plus one death in Louisiana from a new, potentially more dangerous viral strain called D1.1.

Public health experts expressed alarm at the information blockade. "This is incredibly disturbing," said Rachel Hardeman, a CDC Advisory Committee member to the director.

The committee wrote to acting CDC Director Susan Monarez demanding explanations for missing data and delayed studies.

Anne Schuchat, former principal deputy director at the CDC, told KFF Health News that suppressing information could be "potentially confusing, possibly dangerous, and it can backfire."

The data freeze extends beyond flu surveillance.

Doctors For America, representing 27,000 physicians and medical students, filed a lawsuit against multiple federal agencies over the removal of public health information from government websites. The organization alleged that removing critical datasets "creates a dangerous gap in the scientific data available to monitor and respond to disease outbreaks, deprives physicians of resources that guide clinical practice, and takes away key resources for communicating and engaging with patients."

A federal judge ordered health agencies to restore removed datasets and websites by Feb. 14. However, the broader disruption of CDC's disease surveillance and reporting functions continues to hamper medical professionals' ability to respond to what appears to be an unusually severe flu season complicated by emerging viral threats.

CDC spokesperson Melissa Dibble declined to comment on delayed or missing analyses, stating only, "It is not unexpected to see flu activity elevated and increasing at this time of the year."