Perez's positive test was confirmed on Thursday, ruling him out of the British Grand Prix and potentially the 70th Anniversary Grand Prix next weekend.
Since the sport's return almost one month ago, all on-site personnel have been forced to wear face masks and adhere to social distancing when possible.
Perez stated that his predicament shows that everyone is vulnerable to the virus, with Horner stating that F1's safety measures have been justified.
“I think it’s a stark reminder that, sometimes in Formula 1 we are a bit isolated and we all live in our bubbles anyway,” Horner said.
“I think that when it happens to somebody like Perez, a driver, is affected like that, it’s a stark reminder that these procedures are here for a reason and the procedures we take as a team, the procedures we take as a collective in Formula 1, we do everything we can to ensure that as little unnecessary contact is made either at the race event, away from the race event, within the factory.
“It’s very, very difficult and it’s a stark reminder that this thing hasn’t gone away yet. It’s still out there and we are going to be travelling to countries where obviously there are second waves and peaks that are still bubbling away.
“And that’s where as a group, as Formula 1, we do need to keep that discipline with the procedures that are in place. I think that the whole thing was handled well and executed well by the FIA and by the team.”
In the latest round of testing, Perez was the only F1 associate that returned a positive result.
The Mexican driver is now self-isolating in an apartment, with Nico Hulkenberg taking over his seat for the weekend.
With no end date for the 2020 season yet decided and medical staff continuing to work on a virus around the world, Horner says that F1 will be forced to think on its feet as winter approaches.
“I think that it’s inevitable that until a vaccine is found corona is going to be with us for a while to come,” Horner stated.
“Of course it’s about how you manage and control that and with the disciplines that have been put in place we’ve managed to get a season up and running and a championship in play.
“Of course there is going to have to be flexibility and I think that the way that all of the teams have reacted to the moving challenges of this virus.
“We still don’t know the extent of our calendar for this year, we don’t know where we are going to be racing in October, November and even early December, so the teams are having to be flexible, they’re having to think on their feet and work collectively with the governing body and the commercial rights holder and I think that will continue for some time to come.”
Bahrain International Circuit - Winter testing