(The Hill) — The U.S. will head into this year’s fall and winter respiratory virus season with new tools aimed at easing the threat of infections due to a “tripledemic” of COVID-19, respiratory syncytial virus (RSV) and flu. 

Last year saw scores of young children infected by RSV, overwhelming children’s hospitals and emergency rooms across the country. The health system was also pressured by older Americans getting sick from COVID-19 and RSV, though it wasn’t as bad as many feared.

Still, health officials and providers will have new shots for RSV in the coming weeks and months, as well as an updated COVID-19 booster. The youngest kids will have a new monoclonal antibody treatment intended to prevent them from getting RSV.

Here’s what to know:

The COVID-19 booster will likely be available by the end of September

Drugmakers Pfizer, Moderna and Novavax are all designing boosters to target a strain known as XBB. Pending approval by the Food and Drug Administration, they should be on the market in the next month or so.

The XBB strain is a descendant of the highly transmissible Omicron variant that sparked a surge in winter 2021-2022. The current “bivalent” booster has a component aimed at fighting omicron, but also one targeting the original strain of the virus. 

The SARS-CoV-2 virus mutates though, so while the XBB strain was dominant earlier in spring and summer, that’s no longer the case. The Eris subvariant has since grown to command a small majority of cases in the U.S., accounting for about 20 percent of cases. 

Similarly descending from the XBB omicron subvariant, it is closely related to XBB.1.5, and the manufacturers and experts think cross-protection is likely to occur.

But deciding on the strain was the easy part — public health officials will now be tasked with a new messaging campaign to encourage vaccinations among a checked-out public, after poor uptake of the most recent booster.

Older adults and others who are immunocompromised continue to have the highest rates of hospitalization from COVID-19, though it’s unclear whether the new vaccines will be recommended for everyone or just the highest risk. The Centers for Disease Control and Prevention currently recommends that everyone get a bivalent booster.

The COVID shots should still be free for most people

The public health emergency ended in May, meaning the federal government stopped buying vaccines and distributing them to pharmacies, hospitals and physicians’ offices. 

If a patient has private insurance, Medicare or Medicaid, the shots will still likely be free — though the cost will likely be reflected in private insurance premiums. Vaccine makers plan to charge as much as $130 per dose on the private market.

Even with insurance, patients could see costs if they go to an out-of-network provider.  

Uninsured or underinsured Americans will have access to free shots as part of the Biden administration’s “Bridge to Access” program, which will keep a limited supply of vaccines and therapeutics on hand to distribute free through state and local health departments, as well as pharmacies. But they may not be available at pharmacies until mid-October at the earliest.

There are two RSV vaccines for older people 

Pfizer and GlaxoSmithKline both received FDA approval for RSV shots for people aged 60 and older. The new vaccines are expected to be available this fall.

But rather than a blanket recommendation, the CDC said people who want the shot should first talk with their doctors about the risks and benefits. There is a risk for rare side effects related to nervous system disorders like Guillain-Barré syndrome that FDA flagged and the manufacturers are tracking.

Those with underlying medical conditions such as diabetes and chronic heart and lung disease are at increased risk of severe RSV illness as are adults aged 60 and older who are residents of nursing homes and other long-term care facilities.

Data from both companies show a single dose is effective through at least one RSV season. GSK said a single dose worked through two full seasons, explicitly adding that a second dose did not appear to confer any additional efficacy.

Once the vaccines hit the market, accessibility will be a major factor in uptake. GSK said earlier this month that it would price its RSV shot within a range of $200 to $295. Pfizer said it could price its shot between $180 to $270, though that was not guaranteed.

The vaccines should be covered by Medicare Part D, but it’s not clear if private insurance will cover the full cost. 

There’s a preventive RSV treatment for infants, too

Beyfortus, developed by AstraZeneca and marketed by Sanofi, was cleared by the FDA for use in infants up to age 8 months and for high-risk toddlers up to the age of 19 months for preventing RSV infections.

Beyfortus is not a traditional vaccine, but a monoclonal antibody that aims to reduce disease severity and the risk of hospitalization. It’s intended for infants who have never lived through an RSV season but also for certain toddlers who remain vulnerable.

Most people will be exposed to RSV before they are 2 years old, and the virus usually causes cold-like symptoms that go away with rest and self-care.

But infants younger than 6 months who haven’t been exposed have a high risk of developing severe infections that may warrant hospitalization and being placed on a ventilator.

According to the CDC, the ideal timing for the shot to be administered is shortly before RSV season starts, but it can be administered at any time during the season. For infants born shortly before and during the season, the agency recommends they receive it within their first week of being born. 

Based on pre-pandemic patterns, this means the drug could be administered in most of the continental United States from October through the end of March, though the past two seasons have started earlier.

But because it’s not a vaccine, the availability will be trickier because providers may not be certified to administer an injectable therapeutic.

It’s also expensive, at $495 a dose. The CDC cited a “historical lag” in insurers paying for new products, which could be a barrier to certain physician practices who would need to buy the therapies without a promise of reimbursement and without having an idea of the demand.

The treatment should be free for uninsured or underinsured children through the federal Vaccines for Children program, but it’s not clear if that will happen quickly enough for the current season.