As states grappled with confusion around vaccines, COVID-19 cases have continued to fluctuate nationwide.

Some regions of the United States are experiencing "very high" COVID viral activity, according to data from the Centers for Disease Control and Prevention. That's prompted states to take their own action to address cases amid federal turmoil.

While the CDC has slowed its pace in reporting certain COVID data, such as variant prevalence, it continues to track cases, hospitalizations and deaths on a weekly basis.

Here's what to know about this week's data.

How many COVID-19 cases were reported nationwide?

Through the week ending Sept. 13, 9.5% of Americans tested were positive for COVID-19, according to the CDC's latest data. This was a decrease from the prior week (10.9%).

During the same period, 0.8% of all deaths in the United States were attributed to COVID-19, the same as the week before, and 1.2% of all emergency room visits were due to COVID, down from 1.5% in the previous week.

Map of COVID-19 test positivity by region

According to the most recent CDC wastewater data for the week ending Sept. 13, many Western and Southern states had "very high" levels of COVID-19 viral activity. Those states were Alabama, Arkansas, California, Connecticut, Florida, Hawaii, Idaho, Indiana, Louisiana, Nebraska, Nevada, North Carolina, South Carolina, South Dakota and Utah, plus Washington, DC.

What is the most common COVID-19 variant?

The CDC has transitioned to using longer timeframes to release model-based projections about COVID-19 variants because of low reporting from states. According to the latest data projection for the four weeks ending Aug. 30, variant XFG, also known as "Stratus," was the most common, accounting for 78% of cases, followed by NB.1.8.1 at 14% of cases and LP.8.1 at 3%.

XFG, a recombination of variants LF.7 and LP.8.1.2, experienced a meteoric rise to become the predominant strain, having been responsible for 0% of U.S. cases through March, 14% by late June, 42% by early July and 60% by early August.

What are COVID-19 vaccine guidelines?

A battle around COVID-19 vaccines is ongoing among regulators, health officials and experts.

On Aug. 27, Health and Human Services Secretary Robert F. Kennedy Jr. announced that emergency use authorizations for COVID-19 vaccines had been terminated. Instead, the Moderna, Pfizer and Novavax immunizations had been approved only for "those at high risk" and people over 65. This could make it harder for others who want the COVID-19 vaccine to get it, experts warned.

Kennedy previously stated May 27 that the COVID-19 vaccine would no longer be included in the CDC's recommended immunization schedule for healthy children and pregnant women, a move that broke from previous expert guidance and bypassed the normal scientific review process.

On Sept. 19, the CDC's Advisory Committee of Immunization Practices (ACIP) did not implement further restrictions on the vaccine but also fell short of voting on clear recommendations on eligibility. Instead, panel members voted to “promote more consistent and comprehensive informed consent processes” and encourage discussion between patients and providers about the risks and benefits of vaccination. Updated CDC guidelines refrain from making recommendations and instead suggest parents consult with their child's pediatrician on a case-by-case basis.

State health departments and national professional organizations – including the American Medical Association, American Academy of Pediatrics and the American College of Obstetricians and Gynecologists – have broken from Kennedy and HHS on these guidelines, suggesting the vaccine for pregnant women and children and issuing statewide orders to protect access.

The AAP released its own vaccine recommendations on Aug. 19 in a break from federal guidance shaped by Kennedy.

The academy schedule recommends that all children aged 6 months to 23 months receive the latest COVID-19 vaccine to reduce the chance of serious illness. Children and adolescents aged 2 to 18, without other high-risk factors like immunosuppression, can receive and should be offered the vaccine if they were not previously immunized, according to the guidance.

Health insurance companies have also vowed to cover the COVID-19 vaccines "with no cost-sharing for patients through the end of 2026," according to America's Health Insurance Plans.

What are the symptoms of current COVID-19 strains?

While some people report symptoms like hoarseness or "razor blade throat" as being more common with certain variants, health agencies, including the CDC and the World Health Organization, note that there is no evidence of specific symptoms being unique to different strains.

The CDC outlines these common COVID-19 symptoms:

  • Fever or chills
  • Cough
  • Shortness of breath or difficulty breathing
  • Sore throat
  • Congestion or a runny nose
  • New loss of taste or smell
  • Fatigue
  • Muscle or body aches
  • Headache
  • Nausea or vomiting

The CDC advises seeking medical care if you experience any of the following symptoms:

  • Trouble breathing
  • Persistent pain or pressure in the chest
  • New confusion
  • Inability to wake or stay awake
  • Depending on skin tone, lips, nail beds and skin may appear pale, gray or blue

Contributing: Adrianna Rodriguez, USA TODAY

This article originally appeared on USA TODAY: The state of COVID this week: Latest on cases, variants, vaccines and more

Reporting by Mary Walrath-Holdridge, USA TODAY / USA TODAY

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