INFECTION CONTROL NEWSLETTER

October 1999
written by and for Long Term Care Infection Control Nurses

Broad Street Solutions
James Marx, RN, MS, CIC Editor
P.O. Box 16557
San Diego, CA 92176
(619) 656-7887 Voice/FAX New number
jmarx@concentric.net

Influenza Vaccination

Influenza is an upper respiratory tract infection caused by a virus. There is a vaccine to prevent, or at least lessen the symptoms of the disease. There are also antiviral medications available to prevent influenza once is has been detected in your facility. The vaccine must be given intramuscularly.

There are three types of influenza virus:

Type A which causes moderate to severe illness in both animals (chickens and pigs) and humans. The virus can be transmitted from human to human, animal to animal, animal to human and human to animal. Type A effects all age groups and is responsible for pandemics (world-wide epidemic).
Type B causes milder epidemics and effects only humans It primary effects children.
Type C is rarely reported in humans and does not cause epidemics.

Transmission of influenza virus is through the respiratory, probably droplet. This means that transmission occurs only with close contact (within 3 feet). Influenza exhibits a temporal pattern and in the United States will peak between December- March.

Influenza can be transmitted a maximum 1-2 days before to 4-5 days after onset of symptoms. The incubation period, or the time from exposure to onset of symptoms, is 1-5 days. Influenza does not have gastrointestinal symptoms.

Clinical symptoms are an abrupt onset of fever, myalgia, sore throat, nonproductive cough, headache. Severity of illness depends on prior experience with antigenically related variants. The case-fatality - 0.5 to 1 per 1000 cases.

Diagnosis of influenza is made by assessment of clinical and epidemiological characteristics. The influenza virus can be isolated from clinical specimen (e.g., nasopharynx, throat, sputum). Another test is to look for a significant rise in influenza IgG by serologic assay or direct antigen testing for type A virus.

Influenza can have serious complications including Pneumonia (seen as primary influenza pneumonia or secondary bacterial pneumonia), Reye syndrome, Myocarditis, or Death.

The influenza vaccine contains two type A and one type B inactivated virus. It is up to 90% effective in preventing clinical illness in young health adults, 30-40 % effective in preventing clinical illness in frail elderly persons, 50-60% effective in preventing hospitalization, and 80% effective in preventing death.

The most common side effects occur with 6-12 hours after giving the vaccine. They include local pain or swelling reactions, which last for 1-2 days (< 30 %): Fever, malaise which last for 1-2 days (< 1 % ); Severe allergic reaction which is immediate and rarely occurs; Neurological reaction are very rare or nonexistent.

The vaccine is repeated annually and should be given from mid-October through March.

Respiratory Tract Infections

Most outbreaks of respiratory infections in long term care facilities are transmitted via droplets. Most outbreaks are caused by the following pathogens:

Streptococcus pneumoniae-
The most common cause of bacterial pneumonia. While the bacteria can be transmitted person-to-person, respiratory tract infection is not transmitted person-to-person. No special precautions are necessary with residents. Vaccination with pneumococcal vaccine is the most effective prevention measure.

Influenza-
An acute viral respiratory infection causing fever, cough (non-productive), muscle aches, headache and sore throat. Easily transmitted person-to-person via droplets created during coughing and sneezing. (See related article in Influenza)

Tuberculosis (TB)-
A bacterial infection which takes weeks to years after exposure before disease is detected. Not easily transmitted person-to-person via droplet particles which are suspended in the air for a long period of time. The resident should not remain in the facility as long as they are infectious. Contact the local county health department for TB clearance. TB can cause infection outside the lung (i.e. spine, kidney, bone), which is not transmitted person-to-person. This is a reportable disease.

Streptococcus, group A-
Another cause of bacterial infections of the throat (exudative tonsillitis or pharyngitis). Generally not considered to be transmitted person-to-person. Response to antibiotic treatment is usually quick. No special precautions are needed for residents with these types of infections.

Hemophilus influenzae-
Another one of the most common causes of bacterial pneumonia. No vaccine or preventive treatment is available. Not considered to be transmitted person-to-person.

Pertussis-
Generally regarded as a childhood disease (whooping cough) caused by a bacteria. Transmitted via droplet particles. Residents with cough should be restricted from group activities and dining. This is a reportable disease.

Psittacosis-
This is a chlamydial disease transmitted by sick birds. Clinical symptoms are fever, headache, rash, muscle aches and cough. Diagnosis is done by blood testing. Residents should not clean cages where dropping can become aerosolized. This is a reportable disease.