Official State of Rhode Island website

State of Rhode Island Department of Health

Influenza Immunization Information for Healthcare Professionals

Clinical Information

Symptoms

Influenza (flu) illness can include any or all of these symptoms: fever, muscle aches, headache, lack of energy, dry cough, sore throat, and possibly a runny nose. The fever and body aches can last 3-5 days, and the cough and lack of energy may last for 2 or more weeks. The Centers for Disease Control and Prevention (CDC) and Rhode Island Department of Health (RIDOH) define a fever as 100.4ºF/38ºC for people with influenza-like illness.

Influenza can be difficult to diagnose based on clinical symptoms alone because the initial symptoms can be similar to those caused by other infectious agents. Most patients with influenza will have mild illness and can be cared for at home, but some patients, such as infants younger than age 6 months, people with high-risk medical conditions, and anyone with moderate to severe illness, should be seen by a healthcare professional. The CDC provides additional guidance on clinical signs and symptoms of influenza for health professionals.

Treatment

People with influenza who have high-risk medical conditions, who have moderate to severe illness, or who live in households with high-risk individuals should take antiviral medications within two days of getting sick to treat influenza or to prevent influenza transmission.

Laboratory Testing

Healthcare professionals should send samples for rapid diagnostic tests, PCR (polymerase chain reaction) tests, or cultures to commercial or hospital laboratories. Do not send patient specimens to the Rhode Island State Health Laboratory.

The reliability of rapid diagnostic tests depends largely on the conditions under which they're used. Understanding some basic considerations can minimize misinterpreting false-positive or false-negative results. Sensitivities are approximately 50-70% when compared with viral culture or reverse transcription polymerase chain reaction (RT-PCR), and specificities of rapid diagnostic tests for influenza are approximately 90-95%. False-positive (and true-negative) results are more likely to occur when disease prevalence in the community is low and are generally found at the beginning and at the end of the influenza season. Additionally, false-negative (and true-positive) results are more likely to occur when disease prevalence is high in the community.

To minimize false results, healthcare providers can take several important measures:

  • Use rapid diagnostic tests with high sensitivity and specificity.
  • Collect specimens as early as possible, within 4-5 days of the onset of symptoms in a patient.
  • Follow manufacturers’ instructions, including instructions on the proper handling of specimens.
  • Consider sending specimens for viral culture or PCR test to confirm results of rapid tests. This is especially recommended when prevalence of influenza in the community is low and the rapid diagnostic test result is positive, or when the rapid diagnostic test result is negative while disease prevalence is high.
  • The CDC website provides additional information on testing.

Infection Control

Preventing transmission of influenza virus and other infectious agents within healthcare settings requires a multi-faceted approach. The spread of influenza virus can occur among patients, healthcare professionals, facility staff, and visitors. Healthcare professionals can also get influenza from household or community contacts and, in turn, transmit the virus to patients and colleagues. 

The core strategies for preventing the spread of influenza are:

  • Administer influenza vaccine to patients and to staff.
  • Manage all illness among healthcare professionals and staff.
  • Adhere to infection-control precautions for all patient care activities and aerosol-generating procedures.
  • Implement environmental and engineering infection control measures.
  • Promote and implement respiratory hygiene and cough etiquette to staff, patients, and visitors.

Some specific respiratory hygiene recommendations include:

  • When there is increased respiratory infection activity in the community, such as increased school/work absenteeism or an increase in office visits for respiratory illness, offer masks to anyone who is coughing.
  • When space permits, encourage anyone who is coughing to sit at least 3 feet away from others in waiting areas.
  • Advise healthcare staff to use droplet precautions (wear a surgical or procedure mask for close contact) in addition to standard precautions when examining a patient with symptoms of a respiratory infection, especially if fever is present. These precautions should be maintained for 7 days after the patient’s illness onset or for 24 hours after the resolution of the fever and respiratory symptoms (whichever is longer) while a patient is in a healthcare facility.
  • Healthcare staff should wear a properly fitted N95 respirator during during aerosol-generating procedures such as bronchoscopy, sputum induction, intubation and extubation, autopsies, and open suctioning of airways.

Epidemiology

Surveillance

RIDOH's primary method of surveillance is its statewide sentinel physician network. Sentinel physicians are recruited and appointed to report the weekly percentage of patients presenting with influenza-like illness. Sentinel physicians also provide 3 random swabs—one each in early, mid, and late influenza season—for PCR testing. RIDOH works directly with hospital laboratories and/or infection control practitioners to identify confirmed cases of influenza for active surveillance. RIDOH's respiratory virus data are updated weekly.

Reporting Influenza

Healthcare professionals should report any laboratory-confirmed influenza hospitalizations and any influenza-associated deaths to RIDOH. Healthcare professionals should also report any institutional clusters of influenza-like illness, defined as 2 or more influenza cases occurring within a 4-5 day period. Hospital laboratories must report all laboratory-confirmed influenza to RIDOH and specify if a patient is an inpatient or an outpatient. 

To report this information to RIDOH:

  • Phone (Monday-Friday, 8:30 a.m. – 4:30 p.m.): 401-222-2577
  • After-hours phone: 401-276-8046
  • Fax: 401-222-2488

Any healthcare professional who would like to volunteer influenza information for the Rapid Flu Test Reporting Network should call 401-222-2577.

Vaccination

Healthcare professionals interested in vaccinating patients against influenza must enroll in RIDOH’s Office of Immunization State-Supplied Vaccine (SSV) program. Through this program, healthcare professionals can order state-supplied influenza vaccines for both children and adults, as well as vaccines for other diseases.