A child in New Jersey died Sunday after being diagnosed with flu, but the official cause of death is yet to be confirmed. This is the third flu-related pediatric death in the state this season.

Superintendent of Elizabeth Schools Olga Hugelmeyer posted a letter confirming the death on the district's website Sunday. Hugelmeyer confirmed the unidentified student was diagnosed with the flu, although the details remain unclear, adding the matter is currently under investigation by the New Jersey Department of Health.

"It is with great sadness that I must report to you that the Elizabeth School District has lost one of its own," Hugelmeyer wrote in a letter to parents. "On behalf of the district, our team members, students and the Elizabeth Board of Education, I offer our thoughts, condolences and prayers to the family of our student at this heart-wrenching time."

The latest death comes one week after state officials said a second child died after suffering from the virus. The second victim was identified as 6-year-old Nevaeh Hernandez of North Bergen. Another child from Central Jersey died in December, according to the state Department of Health.

New Jersey is battling its highest number of flu cases in 15 years, with more than 4,000 cases reported between Feb. 3 and Feb. 10. More than 14,000 people have been diagnosed since Oct. 7.

flu season Pedestrians pass the Verdugo Hills Medical Clinic where many people are being treated for the flu in Glendale, California, Dec. 27, 2005. Photo: David McNew/Getty Images

Below are some prevention measures, courtesy Centers for Disease Control and Prevention (CDC) that must be adopted to avoid Influenza contraction:

Take a flu vaccine: CDC recommends a yearly flu vaccine as the most important step in preventing influenza infection as the vaccination can protect against 3 or 4 different flu viruses. Even if the vaccine effectiveness was reduced, it may still prevent some flu illnesses, medical visits and hospitalizations. Vaccination of high risk persons, including children, pregnant women, people with chronic health conditions like asthma, diabetes or heart and lung disease and people 65 years and older, is especially important to decrease the risk of severe flu illness.

Children younger than 6 months are at high risk of serious flu illness, but are too young to be vaccinated. However, there are some everyday preventive actions that can be adopted to stop the spread of germs.

1. Try to avoid close contact with sick people.

2. Limit contact with others as much as possible when sick.

3. If sick with flu-like illness, stay home for at least 24 hours after the fever has gone.

4. Cover nose and mouth with a tissue when coughing or sneezing.

5. Wash hands often with soap and water or with an alcohol-based hand rub.

6. Avoid touching eyes, nose and mouth to stop spreading of germs. 

7. Take flu antiviral drugs if your doctor prescribes them.

Flu-like symptoms include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. Some people may also have vomiting and diarrhea.