For your convenience, LISD has compiled important information regarding communicable diseases and health issues. We will continue to post the most current information available.


Influenza (flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness. Influenza is most common during the fall and winter. The exact timing and duration of flu seasons can vary, but activity often begins to increase in October. Most of the time flu activity peaks between December and February, although activity can last as late as May.


Leander ISD follows the guidance and expertise of state and local health officials to help protect our students and staff from all communicable diseases. Texas DSHS announced an update to their Communicable Disease Chart and effective March 24, 2024, COVID-19 is no longer a reportable disease. Students will no longer be excluded for 5 days following a COVID-19 diagnoses and may return to school once they have been fever free for 24 ours without the use of medication.


Pertussis, also known as whooping cough, is a contagious respiratory disease. It is caused by the bacterium Bordetella pertussis.

Pertussis is known for uncontrollable, violent coughing which often makes it hard to breathe. After fits of many coughs, someone with pertussis often needs to take deep breaths which result in a “whooping” sound. Pertussis can affect people of all ages, but can be very serious for babies less than a year old.

More information about Pertussis | Pertussis información en español

Varicella (Chickenpox)

Varicella, also known as Chickenpox, is a contagious disease caused by the varicella-zoster virus. It causes a blister-like rash, itching, tiredness, and fever. Some people who are vaccinated against chickenpox may still get the disease. If this occurs, it is usually milder, with fewer blisters and little or no fever.

Mosquitoes Illnesses

West Nile Virus

To protect yourself and your children, practice the 4 “Ds:”

  • Try to stay indoors at ​Dawn and ​Dusk when mosquitoes are the most active.
  • Defend by using an EPA-approved insect repellent.
  • Dresin long sleeves and pants when outside (particularly during dusk and dawn).
  • Drain standing water in items surrounding your home such as flower pots, pet dishes, ruts and bird baths where mosquitoes can breed.

Parents are encouraged to pre-treat with mosquito repellent before a student comes to school. If you are concerned about the times between dawn and dusk, please consider dressing student in loose-fitting, long-sleeve shirts and long pants.


Zika virus is primarily spread to people through mosquito bites. The virus can be spread from mother to child. Spread of the virus through blood transfusion and sexual contact has also been reported.

Most people infected with the virus have mild or no symptoms. For those who do develop symptoms, illness is generally mild and typically lasts a few days to a week. The most common symptoms of Zika virus disease are fever, rash, joint pain, and conjunctivitis (red eyes).

More information about Zika Zika información en español