2009 H1N1 Flu (referred to as “swine flu” early on) and Seasonal Flu Information for Rheumatology Health Professionals

October 15, 2009, 11:00 AM ET

Are my patients with inflammatory arthritis and rheumatic diseases at high risk for 2009 H1N1 influenza?

People with immunosuppression, either from their medical condition (e.g. inflammatory rheumatic disease) or due to medications, are at high risk for both seasonal and 2009 H1N1 influenza-related complications1,2.  Medications that can weaken the immune system and increase the risk of influenza-related complications include corticosteroids, disease modifying anti-rheumatic drugs (DMARDs), and biological response modifiers.  Although the exact type and severity of immune dysfunction that correlates with risk of influenza-associated complications has not been well defined, patients with more severe immunosuppression are predisposed to serious complications such as prolonged or increased severity of illness.   CDC estimates that almost 6 million adults may be at risk for influenza-related complications because they have inflammatory rheumatic disease.

Rheumatological* diagnoses considered at high risk for influenza-related complications

Rheumatoid arthritis (RA) Systemic lupus erythematosus (SLE) Psoriatic arthritis Anti-phospholipid syndrome Polymyalgia rheumatica Systemic sclerosis/scleroderma Spondyloarthropathies Sjögren’s syndrome Polymyositis/dermatomyositis Vasculitis (e.g., giant cell arteritis) Necrotising arteritis Sarcoidosis Polyarteritis nodosa

* Influenza-related complications have not been examined for all listed conditions, but persons with these conditions have immunosuppression either due to their illness or the medications used to treat their condition.

People with osteoarthritis are likely not at increased risk for influenza-related complications unless they also have another high risk condition such as asthma, diabetes, heart disease, or cancer.

Is there a vaccine against the 2009 H1N1 flu virus and who is it available for?

Yes. A vaccine for the 2009 H1N1 flu has been developed and started to become available October 2009. Patients with inflammatory rheumatic disease within any of the following prioritized groups are recommended to receive the 2009 H1N1 vaccine:

• Pregnant women
• People who live with or care for children younger than 6 months of age
• Healthcare and emergency medical services personnel
• Persons between the ages of 6 months and 24 years old
• Persons between the ages of 25 and 64 years old who are at higher risk for 2009 H1N1 because of chronic health disorders or compromised immune systems (including with inflammatory rheumatic disease)

Persons age 65 or older (including adults age 65 or older with inflammatory rheumatic disease) are not included in these prioritized groups because current studies indicate that the risk for infection among persons age 65 or older is less than the risk for younger age groups.  We do not expect that there will be a shortage of 2009 H1N1 vaccine, but availability and demand can be unpredictable. Once the demand for vaccine among the younger groups has been met at the local level, however, programs and providers should offer vaccination to people age 65 or older, including people with inflammatory arthritis.

Should I advise my patients to get a flu shot?

Yes. Persons with inflammatory rheumatic disease should be advised to receive both:

• A seasonal flu shot every year. 
• The 2009 H1N1 flu shot when available (see question above). These will be available in mid-October 2009.

Persons with inflammatory rheumatic disease should receive the inactivated influenza vaccine which contains fragments of killed influenza virus and is given by an injection.  The live attenuated influenza vaccines (e.g., FluMist®) which are administered by a nasal spray are not recommended in persons with immunosuppression (including persons with inflammatory rheumatic disease).  Live attenuated influenza vaccine is approved for use in healthy people 2-49 years of age.

Updates regarding the availability, distribution, and dosing of H1N1 vaccine are available.

What else should I tell my patients with inflammatory rheumatic disease who develop flu-like symptoms?

• If you develop flu-like symptoms contact your healthcare provider.
• Avoid contact with others. Seek medical care early. You should stay home and avoid travel, including not going to work or school, until at least 24 hours after your fever is gone except to get medical care or necessities. Your fever should be gone without using fever-reducing medications.
• If you leave the house to seek medical care, wear a facemask, if available and tolerable, and cover your coughs and sneezes with a tissue.
• Do not stop taking any medicine you take for your arthritis unless told to do so by your physician.
• Seek medical attention early. Treatment is available for persons with severe disease and those at high risk for complications. Persons with inflammatory rheumatic disease are considered high risk for complications from the flu; therefore, your health care provider may choose to prescribe antiviral medications for you if you get the flu.
• If you are exposed to someone who has flu, consult your health care provider.  They may prescribe medication to help prevent you from getting the flu or watch you closely to see if you develop flu symptoms.

Do rheumatology health professionals need to get a flu shot?

Yes. CDC recommends all healthcare providers receive both the seasonal influenza vaccine every year and the 2009 H1N1 vaccine. Healthy persons (including healthcare providers) who are infected with influenza virus, including those with subclinical infection, can transmit influenza virus to persons at higher risk for complications from influenza, such as patients with inflammatory rheumatic disease. Persons working in healthcare settings who should be vaccinated include physicians, nurses, other workers in both hospital and outpatient settings, medical emergency-response workers, employees of nursing home and long-term care facilities who have contact with patients or residents, and students in these professions who will have contact with patients.

Should I prescribe empiric antiviral medications for my patients with inflammatory rheumatic disease and suspected influenza?

Clinical judgment is an important factor in treatment decisions.  Although most patients who have had 2009 H1N1 virus infection have had a self-limited respiratory illness similar to typical seasonal influenza, early empiric treatment with oseltamivir or zanamivir should be considered for persons with suspected or confirmed influenza who are at higher risk for complications including patients with inflammatory rheumatic disease.

Detailed antiviral treatment recommendations are available.

Most healthy persons who develop suspected or confirmed 2009 H1N1 influenza or seasonal influenza who present with an uncomplicated febrile illness generally do not require antiviral treatment. However, persons presenting with suspected influenza and more severe symptoms such as evidence of lower respiratory tract infection or clinical deterioration should receive prompt empiric antiviral therapy, regardless of previous health or age.

If treatment is indicated, antiviral therapy should not wait for laboratory confirmation of influenza because laboratory testing can delay treatment and because a negative rapid test for influenza does not rule out influenza.  Detailed influenza diagnostic testing information is available.

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References

1. CDC. Use of influenza A (H1N1) 2009 monovalent vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009 MMWR.  2009:58(RR-10):1–8.

2. CDC. Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009. MMWR 2009;58(RR-8):1–43.

3. CDC. Updated Interim Recommendations for the Use of Antiviral Medications in the Treatment and Prevention of Influenza for the 2009-2010 Season.