As Omicron cases are sweeping the nation, some experts are warning that being outdoors may not provide as much protection as before. Dr. Mallika Marshall explains:

Omicron subvariants BA.4 and BA.5 are highly transmissible, some say as transmissible as measles, which is considered the most infectious viral illness in humans.

With previous coronavirus variants, like alpha and delta, being outdoors provided good protection against infection, but with the newest Omicron subvariants, being at an outdoor event could be somewhat risky.

If you are high-risk or have close contact with someone who is high risk, wear a mask indoors, even if you’re just running inside to use the restroom or grab something quickly from a store. Wear a mask outdoors if you’re going to be in close proximity to others.

We used to say it would take about 15 minutes of close contact to catch the virus if around from someone who was infected. The 15-minute rule no longer applies. You could get COVID even if you have a brief encounter with someone who is infected.

Having a prior infection with another Omicron subvariant does provide some immunity against BA.4 and BA.5 but it’s not absolute. These newer subvariants have additional mutations in the spike protein allowing them to evade immunity, so even if you had COVID earlier this year, don’t assume you’re in the clear from getting it again.