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Influenza, Southern Hemisphere

Influenza is a world-wide contagious respiratory illness caused by influenza viruses. The virus is spread through close contact with an infected person. The incubation period is commonly 2 days, but ranges from 1 to 4 days. Due to its short incubation period, influenza outbreaks may escalate very quickly, especially in highly susceptible populations. Influenza illness is characterized by the abrupt start of fever, sore throat, headache, myalgia, non-productive cough and extreme fatigue with major symptoms lasting an average of 2 to 3 days. Fever usually ranges between 100° and 104°F. Illness typically improves within a week, but cough and malaise may persist for 2 or more weeks. The most common complications of influenza is pneumonia, but may include exacerbation of underlying chronic pulmonary and cardiopulmonary diseases, such as chronic obstructive pulmonary disease, asthma, and congestive heart failure.

There are many brands of Northern Hemisphere influenza vaccines available. Recently, one brand of vaccine for Southern Hemisphere influenza vaccine became available in the United States. 

Northern Hemisphere influenza vaccine will be administered to all assigned to an area designated as a Northern Hemisphere influenza zone between October and April. Southern Hemisphere influenza vaccine will be administered to all permanently or temporarily assigned to an area designated as a Southern Hemisphere influenza zone between April and October. Northern and Southern Hemisphere-designated countries will be identified by the Defense Health Agency or the Type/Combatant Command to which an individual may be permanently or temporarily assigned.  Personnel traveling to either the Northern or Southern Hemisphere during that hemisphere’s influenza season should be vaccinated at least two weeks prior to entry into the region.  Northern and Southern Hemisphere influenza vaccines should be separated by at least 28 days.

You will find below all of the resources you will need for the Southern Hemisphere influenza season. More will be added as they are published or released.

Policy Date 
Defense Health Agency-Procedural Instruction (DHA-PI) 6025.34: Guidance for the DoD Influenza Vaccination Program (IVP)
Aug. 21, 2020
DHA IPM 20-002: Southern Hemisphere Influenza Vaccination Program
March 20, 2020 
Information Paper Date 
Influenza Infections and Influenza Vaccine Aug. 19, 2021 
Influenza Vaccines for Adults 65 Years and Older Aug. 19, 2021
Vaccine Information Statements Date 
Live, Intranasal Flu Vaccine (CURRENT FOR THE 2020-21 SEASON) Aug. 6, 2021
Inactivated or Recombinant (injectable) Flu Vaccine (CURRENT FOR THE 2020-21 SEASON) Aug. 6, 2021
Screening Form Date 
Pediatric and Adult Influenza Screening and Immunization Documentation (Use Internet Explorer to access the form)

Last Modified
July 2021
Originally Published
February 2020

Competency Assessment Date 

Initial/Annual Competency Assessment Checklist: INFLUENZA VACCINE ADMINISTRATION

Aug. 19, 2021
Package Inserts Date 
Fluzone (Quadrivalent) Southern Hemisphere (Prescribing information starts on page 2) Feb. 4, 2021
Standing Orders Date 
Influenza Vaccines for Children and Adolescents Oct. 25, 2021
Influenza Vaccines for Adults Aug. 19, 2021
  August 1, 2017
  August 1, 2017

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DHA IPM 20-002: Southern Hemisphere Influenza Vaccination Program


This Defense Health Agency-Interim Procedures Memorandum (DHA-IPM), establishes the Defense Health Agency’s (DHA) procedures to implement instructions, assign responsibilities, and prescribe procedures for the Southern Hemisphere Influenza Vaccination Program. All Active Duty, Selected Reserve, and National Guard members receive an annual influenza vaccination. Personnel who are traveling to, conducting a permanent change of station to, or are located in the Southern Hemisphere will receive the Southern Hemisphere influenza vaccine or obtain an exemption (e.g., medical or administrative) in accordance with guidance in paragraph 6.a. of Attachment 2. Military personnel residing in the Southern Hemisphere who have received the Southern Hemisphere influenza vaccine in accordance with Appendix 1, meet the annual influenza immunization requirement.

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