If you are sniffling, coughing and feeling feverish, you may have the flu. And you are not alone. There have been at least 15 million cases of the flu in the United States since late September, according to the Centers for Disease Control and Prevention’s most recent estimates, and 7,400 flu-related deaths.
Influenza cases in the United States haven’t yet reached their peak, but it’s already proving to be “a really bad” flu season, said Richard A. Martinello, an infectious-disease expert and medical director of the infection prevention department at Yale New Haven Health. There have been about 180,000 hospitalizations for flu complications, and those continue to rise, according to the CDC.
A flu vaccine, usually available in August or September, is the best protection against the flu. And it’s not too late to get a flu shot, Martinello said. He recommended getting one “really as soon as possible to protect yourself,” although it can take a couple of weeks to ramp up and fully take effect.
But even if you already got a flu shot, you can still get influenza. The vaccine is generally 40 to 60 percent effective, and immunity may last only about six months. (Flu shots are considered effective if they reduce hospitalizations and deaths, so if you do get sick, your symptoms should be milder than if you didn’t get a flu shot.)
If you test positive for the flu at your doctor’s office or with an at-home influenza test kit, there are many treatments. But which ones actually work? We asked several experts.
Influenza causes and symptoms
Influenza, a respiratory illness, is mainly caused by two types of viruses, influenza A and B, which are constantly evolving. The current surge in infections is driven by a new H3N2 variant called subclade K, a fast-spreading type of influenza A. It “seems to be the predominant strain that is circulating,” said Judith O’Donnell, the associate chief medical officer for health care epidemiology at the University of Pennsylvania Health System.
When an infected person, in the contagious stage, coughs, sneezes or talks, their droplets can spread the viruses, the CDC said.
The most common flu symptoms are fever, cough, sore throat, runny nose, aches and fatigue, with children more likely to also have vomiting and diarrhea, according to the CDC.
Not everybody needs treatment, said Tina Ardon, a family physician in Jacksonville, Florida, with the Mayo Clinic. Most people with the flu get better after a few days of rest and over-the-counter medications such as acetaminophen and ibuprofen.
“But for the right patients, antiviral medication can be really important,” Ardon said.
Antiviral medications can shorten flu duration
There are four antiviral medications approved by the Food and Drug Administration to treat the flu. Three fall into the same class of drugs, called neuraminidase inhibitors. The most well known and frequently prescribed of these is oseltamivir (Tamiflu).
It can be taken by anyone over 2 weeks of age, unless there’s some contraindication, Martinello said. You generally take oseltamivir as an oral pill or liquid twice a day for five days.
Oseltamivir can decrease the risk of complications, hospitalizations and death, he said.
The most common side effects are nausea and vomiting.
The two other neuraminidase inhibitors are prescribed less often to treat the flu, experts said. One, called parimivir, is an intravenous medication used in hospitals.
Another, zanamivir, comes in powder form and is administered with an inhaler. “We know this medication actually works very well,” Martinello said, “but it can be a little more challenging to coordinate in this device than simply swallowing a pill.”
Zanamivir is approved for people ages 7 and older, but it’s not recommended for those with breathing problems such as asthma. Like oseltamivir, it’s a twice-a-day, five-day treatment.
Baloxavir (Xofluza) is the fourth antiviral option to treat flu in those ages 5 and up. “It’s a newer agent, and the advantage is that it’s a single dose,” said Lisa Maragakis, a hospital epidemiologist and senior director of infection prevention for Johns Hopkins Health System.
This convenience means baloxavir is sometimes prescribed by emergency room physicians, Martinello noted. “It really saves a lot of time,” he said. “It gets them treated a few hours earlier, which may make a difference early on in their illness.”
Not all insurance companies cover baloxivir, he pointed out, so it can be more expensive out of pocket. This antiviral medication is also not approved for pregnant or breastfeeding women, though oseltamivir has been found to be safe for these groups.
How effective are these treatments?
There haven’t been many head-to-head trials comparing the medications, experts said, but antivirals generally reduce flu symptoms and shorten illness by around a day. This “may not sound like a lot,” Maragakis said, “but when you’re feeling so miserable, [it’s] a big deal.”
Taking antiviral medication might offer other benefits. Both oseltamivir and baloxavir can be used post-exposure, “hopefully preventing flu in someone who’s had exposure,” Ardon said. If you know you’ve recently interacted with someone who tested positive, these medications may help you avoid illness yourself.
Studies also suggest these drugs may reduce viral shedding, so you’re less likely to spread the virus. This can be particularly important for those in large households or who interact with at-risk individuals. For example, “if you’re part of a family and you have an elder in the house, we need to treat as soon as possible to shorten the course and potentially reduce risk of transmission,” said Kathleen Mueller, a family physician and director at the American Academy of Family Physicians.
Timing is a barrier when it comes to treatment
The biggest downside of antiviral medications for flu is that they need to be taken within 48 hours of symptom onset. Many people miss the window to benefit from treatment.
“It can be really hard, because the person’s probably at home, they get sick, the next day they’re feeling worse and the third day they call their doctor, and by then it’s too late — they still need to get tested and pick up the medicine from the pharmacy,” Martinello said.
Give yourself an edge in getting a prescription faster with these two steps.
Keep a few flu tests at home. If you test positive, you can contact your physician for a prescription without scheduling an in-office test.
“Now that we have the combination covid and flu home tests, I think that’s a really valuable tool for being able to define the two viral illnesses and knowing how to approach it,” Mueller said.
Use telehealth to avoid the delay of in-person appointments. “It can be much easier now, not only to reach your own physician but any physician,” Martinello said.
Who needs to take antiviral medication?
The CDC recommends treatment for anyone who has or suspects they have the flu and is at increased risk of complications. This includes people younger than 4 to 5 years or those over 65, Martinello said.
Certain health conditions also increase a person’s risk of flu complications regardless of age. If you are an adult “taking chronic medication that involves your lungs, your heart, your kidneys, you’ve had a prior stroke, you’re immunocompromised or are taking medications that make you immunocompromised — which is a broad swath of adults in the United States — there is benefit to taking an antiviral,” O’Donnell said.
If you’re young and otherwise healthy, you probably don’t need treatment, according to the CDC, especially if you can isolate yourself at home and avoid exposing at-risk people. But it still may be worth talking to your doctor about what they recommend.
“It can really make people get back to work sooner, feel better sooner and get fever-free sooner,” O’Donnell said.
Someone at higher risk who tests positive for flu after the 48-hour window should also discuss their options with a provider. Even though treatment works best within two days of symptom onset, the CDC says a later start may still be beneficial for someone with severe illness or higher complication risk.
Vaccination remains the best protection against the flu
The flu vaccine might not prevent you from getting influenza, experts said, but it could make your illness less severe and help you get back to your regular routine sooner.
“You go from the risk of ending up in the hospital or developing a bacterial superinfection of your lungs to having something where you can basically stay at home and treat it at home,” O’Donnell said.
The 2025-2026 influenza vaccine was developed before the subclade K variant began spreading. And while experts had concerns about its effectiveness, recent data from Britain suggests the vaccine “still has some substantial benefit,” Martinello noted. Those findings show that Britain’s flu vaccine has continued to provide effective protection from hospitalization.
If you haven’t gotten your flu vaccine this year, you “absolutely” should, Maragakis stressed. That’s also true if you already had the flu and weren’t vaccinated, she said, since different strains are circulating at the moment.
“Even if you’ve had the flu, even if you’ve waited and you think maybe it’s too late [to get vaccinated], it’s not,” she said.
The post Got the flu? Here’s what to know about antivirals to fight it. appeared first on Washington Post.
