Department of Health officials say that all four people who have died in the city's H1N1 flu outbreak had "underlying medical conditions."

City officials have not released the specific causes of death for the four cases, and insufficient data are available to determine who is at higher risk for complications of H1N1 influenza virus infection.

However, the same age and risk groups who are at higher risk for seasonal influenza complications should also be considered at higher risk for swine-origin influenza complications. Some pre-existing medical conditions that could worsen seasonal influenza include asthma, obesity, diabetes, lung disease and heart disease.

Populations At Higher Risk Of Flu Complications

According to the Centers for Disease Control and Prevention, groups at higher risk for seasonal influenza complications include:

• Children less than 5 years old.
• Persons aged 65 years or older.
• Children and adolescents under the age of 18 who are receiving long-term aspirin therapy and who might be at risk for experiencing Reye syndrome after influenza virus infection.
• Pregnant women.
• Adults and children who have chronic pulmonary, cardiovascular, hepatic, hematological, neurologic, neuromuscular, or metabolic disorders.
• Adults and children who have immunosuppression (including immunosuppression caused by medications or by HIV).
• Residents of nursing homes and other chronic-care facilities.

High-Risk Children's Medical Conditions

Department of Education officials say that sick children with flu-like symptoms should be kept out of school until 24 hours after their symptoms resolve.

The great majority of children recover from influenza quickly without treatment, but those with chronic underlying health conditions should call a doctor about receiving antiviral treatment.

Children at higher risk of severe flu complications include:

• Infants younger than six months.
• All children with immune suppression.
• Pregnant adolescents.
• Children with chronic kidney disease, heart disease, sickle cell disease.
• Children with HIV/AIDS.
• Diabetic children.
• Children with asthma or other problems of the lungs
• Children on long-term aspirin therapy for chronic disorders.
• Children with any condition that affects respiratory function including neurological conditions such as intellectual and developmental disability, cerebral palsy, spinal cord injuries, seizure disorders, metabolic conditions or other neuromuscular disorders.

Seek Hospital Treatment For Certain Symptoms

According to the DOH, people with worsening flu symptoms should visit a doctor or a hospital right away. Those who are not sure where to get car can call 311 for information.

Care is always available for those who need it, and no one will check patients' immigration status.

Some signs to get medical treatment can include:

Adults
• Trouble breathing or shortness of breath.
• Pain or pressure in the chest or stomach.
• Sudden dizziness.
• Confusion.
• Severe vomiting that won’t stop.

Children

• Fast breathing or trouble breathing.
• Bluish skin color.
• Fever with a rash.
• Refusal to drink fluids.
• Vomiting or diarrhea that won’t stop.
• Not waking up or not interacting.
• Being too irritable to be held.
• Having flu symptoms return with fever and worse cough after starting to get better.