FORUM
DRUG ALERT

Recommendations pertaining to the use of viral vaccines: Influenza 2008

Recommended vaccine formulation

The following strains have been recommended by the World Health Organization for the 2008 Southern Hemisphere influenza season:

• A/Solomon Islands/3/2006 (H₁N₁)-like virus
• A/Brisbane/10/2007 (H₃N₂)-like virus
• B/Florida/4/2006-like virus.

The following viruses are suitable vaccine strains:

• A/Solomon Islands/3/2006 (H₁N₁) (IVR-145)
• A/Brisbane/10/2007 (H₃N₂) (IVR-147)
• B/Florida/4/2006 or B/Brisbane/3/2007.

Vaccines should contain 15 ug of each haemagglutinin antigen in each 0.5 ml dose.

Indications

1. Persons (adults or children) who are at high risk for influenza and its complications because of underlying medical conditions and who are receiving regular medical care for conditions such as chronic pulmonary and cardiac disease, chronic renal diseases, diabetes mellitus and similar metabolic disorders, and individuals who are immunosuppressed (including HIV-infected persons with CD4 counts above 200/µl).

2. Residents of old-age homes, chronic care and rehabilitation institutions.

3. Children on long-term aspirin therapy.

4. Medical and nursing staff responsible for the care of high-risk cases.

5. Adults and children who are family contacts of high-risk cases.

6. All persons over the age of 65 years.

7. Women who would be in the second or third trimester of pregnancy during the influenza season. Pregnant women with medical conditions placing them at risk for influenza complications should be immunised at any stage of pregnancy.

8. Any persons wishing to protect themselves from the risk of contracting influenza, especially in industrial settings, where large-scale absenteeism could cause significant economic losses.

Dosage

• Adults: Whole or split-product or subunit vaccine -1 dose IM.
• Children (<12 years): Split-product or subunit vaccine - 1 dose IM.
• Children <9 years who have never been vaccinated should receive 2 doses 1 month apart.
• Children less than 3 years of age should receive half the adult dose on 2 occasions separated 1 month apart.

Contraindications

1. Persons with a history of severe hypersensitivity to eggs.

2. Persons with acute febrile illnesses should preferably be immunised after symptoms have disappeared.

3. The vaccine should be avoided in the first trimester of pregnancy unless there are specific medical indications -see above, indication No. 7.

Timing

Vaccines should be given sufficiently early to provide protection for the winter. A protective antibody response takes about 2 weeks to develop.

Department of Health
B D Schoub
(barrys@nicd.ac.za)