Class is back in session after some sick kids and teachers caused entire school districts and a school to shut down.
The affected schools have spent the last week deep cleaning campuses, something they do throughout the year to ward off germs.
But Dallas County Health & Human Services said it's especially important to implement additional measures to prevent the spread.
"As a general indicator, schools reporting greater than 10% absences due to influenza-like illness, for more than two consecutive days, are asked to review their absences and assess a number of additional factors—including whether the trend is increasing or decreasing, and whether significant numbers of staff are affected," said the health department said in a statement to NBC 5. "DCHHS encourages parents of students and school staff to stay home when sick until at least 24 hours after they no longer have a fever as well as encourage routine surface cleaning in the schools to slow the spread of flu."
Rio Vista ISD closed halfway through the day on Feb. 11 because about 100 of the 770 students across the entire district were sick. Around 60 students were out at just one elementary school alone.
The next day on Feb. 12, Grand Saline ISD closed due to low attendance from flu, strep and other sicknesses.
The latest news from around North Texas.
The district said it deep cleaedn all areas of the school to help prevent students from getting sick.
Superintendent Micah Lewis told NBC 5 on Monday that a big reason for the closure was because too many teachers were sick as well and they couldn't find enough substitutes to cover the absences. Bus drivers were also sick, affecting the transportation flow.
The elementary school only had an 81% attendance rate, when it was normally above 95%, Lewis said.
Over in the Dallas County, the health department says St. Thomas Aquinas Catholic School closed for similar reasons, giving teachers and kids five days to recover and allowing some more time to deep clean the school.
The health department clarified they never order the closures but do offer guidance and recommendations when schools report more than 10% absences for two days in a row.
Students at these schools will not be required to make up the days during which the school is closed.
Latest flu numbers
It seems the flu is far from over for North Texas.
MedStar's latest data shows crews are still treating an average of more than 9 patients per day for the flu, up 63% from this time last year.
According to the latest data posted by Dallas County Health, flu activity is still high, with 23% of tests coming back positive. Click here to access the latest influenza surveillance report.
In just Dallas County alone, 17 flu-related deaths have been reported with more unconfirmed.
Several doctors have also said they are expecting another peak to the flu season toward the end of this month, so we are not out of the woods yet.
Across the country, the CDC estimates that so far this season there have been at least 26 million flu illnesses, 250,000 hospitalizations and 14,000 deaths from flu.