The Centers for Disease Control and Prevention (CDC) have reported that during the third week of the year (January 14-20, 2018), influenza activity increased in the United States.
- Influenza-associated Hospitalizations: A cumulative rate of 41.9 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
- Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 6.6%, which is above the national baseline of 2.2%. All 10 regions reported ILI at or above region-specific baseline levels. New York City, Puerto Rico, and 39 states experienced high ILI activity; the District of Columbia and five states experienced moderate ILI activity; three states experienced low ILI activity; and three states experienced minimal ILI activity.
- Geographic Spread of Influenza: The geographic spread of influenza in Puerto Rico and 49 states was reported as widespread; Guam reported regional activity; the District of Columbia and one state reported local activity; and the U.S. Virgin Islands reported sporadic activity.
Why is this years’ flu season so deadly?
Dr. Amesh Adalja, an infectious disease physician and senior scholar at the Johns Hopkins Center for Health Security links the viciousness of this years’ flu season to the nature of the flu strains that are circulating.
Dr. Adalja said that “This year is particularly bad because it’s dominated by the H3N2 [flu strain], which tends to be more severe and causes more severe symptoms than other strains of flu.”
This is confirmed by the CDC’s viral surveillance which recorded that “the most frequently identified influenza virus subtype reported by public health laboratories during week 3 was influenza A(H3).”
Why does the flu cause death?
The flu virus in an of itself does not cause death. Death is caused by what the flu virus does to the body.
Dr. Adalja says that “Dying from the flu is not like dying from a bullet or a black widow spider bite. The presence of the virus itself isn’t going to be what kills you. An infectious disease always has a complex interaction with its host.”
Kathleen Sullivan, Chief of the Division of Allergy and Immunology at The Children’s Hospital of Philadelphia, estimates that “about one-third of people who die from flu-related causes expire because the virus overwhelms the immune system. Another third die from the immune response to secondary bacterial infections, usually in the lungs; and the remaining third perish due to the failure of one or more other organs. These findings are based on autopsy studies.”
When the flu virus enters the body, usually through the eyes, nose or mouth, it begins hijacking human cells in the nose and throat and fools them into duplicating themselves. The immune system, sensing it is under heavy attack mounts a massive defense. It sends large amounts of white blood cells, antibodies and, inflammatory molecules to fight the intruder.
As the immune system is focused on fighting the flu virus it becomes weakened leaving it vulnerable to other issues.
The flu virus can cause a wide range of complications that range from mild to severe including death.
- Bacterial pneumonia
- Sinus and ear infections
- Myositis and
- Reye’s syndrome
- Guillain–Barré syndrome
What is the difference between a cold and the flu?
The symptoms of a cold often mimic those of the flu so it is tough to tell them apart. Though the flu and the common cold are both respiratory illnesses, they are caused by different viruses.
One telltale sign that you have the flu and not the common cold is the manner in which the symptoms appear. Check out the CDCinfographicc below for more information.
Who is at High Risk of Developing Flu-Related Complications?
According to the CDC, the following groups of people are at high risk of developing flu-related complications.
- Children younger than 5, but especially children younger than 2 years old
- Adults 65 years of age and older
- Pregnant women (and women up to two weeks postpartum)
- Residents of nursing homes and other long-term care facilities
- American Indians and Alaska Natives seem to be at higher risk of flu complications
- People with the following medical conditions – Asthma, Neurological and neurodevelopmental conditions, Chronic lung disease, Heart disease, Blood, Endocrine Kidney, Liver and Metabolic disorders, those with already weakened immune system due to disease or medication, people younger than 19 years of age who are receiving long-term aspirin therapy and, people with extreme obesity (body mass index [BMI] of 40 or more)
What should you do if you think you have the flu?
According to the CDC, “Most people with the flu have mild illness and do not need medical care or antiviral drugs. If you get sick with flu symptoms, in most cases, you should stay home and avoid contact with other people except to get medical care.
If, however, you have symptoms of flu and are in a high-risk group, or are very sick or worried about your illness, contact your health care provider (doctor, physician assistant, etc.).”