Winter viruses have been surging in recent weeks, in the midst of the year’s busiest travel season. As families prepare to crowd onto planes and gather at holiday dinner tables, overcrowded emergency rooms from Philadelphia to Los Angeles are grappling with hours-long wait times and record-high patient admissions.

The rush has been largely fueled by the triple threat of COVID-19, RSV, and influenza, a brutal combination of respiratory illnesses that have surged all at once. Some state and local officials have issued emergency orders to assist their overwhelmed medical systems by easing access to health workers and treatments.

“The past several years have certainly not been easy, and now we face another surge of illness,” said Dr. Rochelle Walensky, director of the U.S. Centers for Disease Control and Prevention, during a media briefing in early December. “Another moment of overstretched capacity, and really one of tragic and often preventable sadness.”

Influenza and RSV struck harder and earlier this year, emerging months before their typical start in October. Now, nearly every state is reporting “high” or “very high” flu spread. More than 25,900 patients were hospitalized due to the virus last week, making it one of the worst seasons for the respiratory illness in the last decade, according to CDC data. RSV hospitalizations have declined from last month’s peak, but also remain well above previous years.

Meanwhile, COVID-19 case numbers are experiencing the annual holiday-season jump, though cases and deaths remain significantly lower than the past two winters.

The COVID-19 virus hit Black Americans particularly hard, and as the pandemic continued, the disparities appear to have narrowed. Racial disparities also are seen in flu infections, with Black Americans hospitalized at about three times the rate of white Americans. And research has shown that Black children are more likely to be hospitalized for RSV than white children, as well.

Here’s what you need to know about the “tripledemic” to help keep your family safe ahead of your holiday travel.

What is respiratory syncytial virus, or RSV?

RSV, or respiratory syncytial virus, is a common respiratory virus that typically causes mild cold symptoms. But for young children, it is the most common cause of bronchiolitis and pneumonia, which may require hospitalization for the most severe infections. This year, it has overwhelmed many children’s hospitals nationwide.

Premature babies and those born with weakened immune systems or chronic lung disease are most at risk. Across the country, an estimated 58,000 to 80,000 children younger than 5 years old are hospitalized each year, according to the CDC. Similarly, those over the age of 65 with preexisting conditions are most at risk for severe RSV complications.

You may be contagious a day or two before you start showing signs of RSV infection.

What is the difference between RSV, COVID-19, the flu, and a common cold?

The three viruses are transmitted in similar ways. The coronavirus is transmitted through prolonged close contact with an infected person. RSV and the flu are transmitted through droplets in an infected person’s cough or sneeze, as well as direct contact with the virus on surfaces.

Many symptoms of the flu, COVID-19, and RSV overlap. A sore throat, cough, fever, and fatigue are all common. There are some differences, however.

While sneezing is common with RSV, it happens only occasionally with the coronavirus and is unlikely a symptom of the flu. Aches are rarely a symptom of RSV and are sometimes a symptom of COVID-19, but they are common with the flu. Flu symptoms tend to run their course within one to two weeks, while COVID-19 symptoms may last longer. RSV symptoms typically improve within a week’s time.

Health experts do not recommend attempting to self-diagnose or dismiss symptoms.

“The best thing to do is go and get tested,” said Natasha Williams, an associate professor of population health at New York University. “If you can, talk with a medical provider.”

How do I get tested for RSV, COVID-19, and the flu?

Some pharmacies, like CVS, offer in-person testing for the coronavirus and flu, which consists of swabbing the nose or throat. Many hospital providers and urgent care centers are able to test for all three viruses.

For RSV, a health care provider can administer the test, which includes either a nasal wash or swab.

Testing as early as possible is recommended, said Williams. There are safe and effective treatments that can be administered in the first few days of COVID-19 and flu infections that can protect patients from the most severe illness.

Paxlovid is an antiviral drug approved by the U.S. Food and Drug Administration for use among patients who had tested positive for the coronavirus, are over 65 years old, or have preexisting conditions that may increase the likelihood of severe infection, such as diabetes or cancer. It may also reduce the risk of long COVID.

The drug must be started within five days of symptom onset to be effective.

How do I prevent infection?

As many prepare to gather with family this winter, many of the same safety precautions put into place over the past three years will protect those most vulnerable from each of the viruses, health experts say.

“The recommendations from early on in the pandemic still are effective, and that includes hand-washing, wearing a mask in crowded spaces where there is poor ventilation, testing, and the vaccine,” said Williams.

Masking is particularly important for those living in high transmission areas for COVID-19, which includes just under 10% of the U.S. population. A number of localities across the country are issuing new mask mandates as case numbers increase, including counties in California and New York.

And with an earlier and more harsh flu season this year, the CDC recommends that everyone over 6 months old get a flu vaccine if they have not already.

There is no vaccine currently available for RSV, although there are some in development. Pfizer’s vaccine for older adults is awaiting FDA approval.

Traditional public health methods also help in slowing the spread of germs. Those include frequent handwashing and use of hand sanitizer; keeping your hands off of your eyes, nose, and mouth; avoiding close contact with sick people; covering coughs and sneezes; and disinfecting surfaces often.

If you are feeling sick, stay home from work and school, and avoid public places and close contact with others.

Is it too late for the flu shot?

Although winter has already begun, it is not too late to be vaccinated this season, said Williams. “People should still consider getting the flu vaccine. It is highly recommended.”

Last year, 42% of Black Americans were vaccinated against the flu, compared with more than 50% of white Americans, CDC data shows. It’s an inequity that may be one of the driving forces behind the racial disparities in hospitalizations.

It is especially important for those under the age of 5 or over 65 and those who are pregnant or have underlying conditions. Those are the groups that tend to be hospitalized, said Walensky with the CDC.

You can get a flu shot and COVID-19 booster administered in the same visit, so long as you are due for both.

How do I know if I am in a high transmission area for COVID?

The CDC’s COVID-19 Community Levels are determined based on the number of new cases and new hospital admissions per 100,000, along with the percentage of hospital beds in use by patients infected with the virus in a specific county over the past seven days.

A number of counties scattered across the country are currently designated as high transmission areas. About 10% of the population is living in a high transmission area, which includes counties in Arizona, California, New Mexico, and some states in the Midwest.

Margo Snipe is a health reporter at Worldacad. Twitter @margoasnipe