Nini, DD had RSV as well and lost half a pound will her illness. Since she's been sick, her sleep has been terrible and in the past week or so, she's been waking every 2 hours. Sometimes I manage to resettle her (gas trouble, paci, etc) but most often, I've had to feed her. I think she was trying to regain her lost weight. The past couple of nights, she's only woken once in addition to her "dreamfeed" (which she's also waking for), so I'm guessing that when she's back up with her weight, that feed will gradually drop off as well.
All this to say, I would have patience for a week or so and feed her at night if she's waking for it. After such an illness, she's probably just catching up. Once her weight is back up, I bet her NWs will gradually drop off and she'll go back to STTN.
During the day, I would keep the feeds spaced out to encourage her to take a proper feed instead of snacking. With DD, I was trying to feed her more often to help her gain back her weight, but I think it was backfiring on me as she wasn't eating well at the feeds and was waking a lot at night. I think I was basically encouraging her to "snack" around the clock. The past couple of days I've done the opposite and pushed her out to 4 hours for the most part (we've never gone that long between feeds before) and she's been eating better during the day, and waking less at night.