Statement of Principles concerning influenza (Reasonable Hypothesis) (No. 44 of 2017)

This instrument, the Statement of Principles concerning influenza (Reasonable Hypothesis) (No. 44 of 2017), is a legislative determination made by the Repatriation Medical Authority under subsection 196B(2) of the Veterans' Entitlements Act 1986 (VEA). It sets out the minimum factual conditions that must exist before a reasonable hypothesis can be raised linking influenza, or death from influenza, with the circumstances of a person's relevant service. In mechanical terms, it replaces the earlier SoP No. 58 of 2009 and applies to claims for compensation or treatment under the VEA and the Military Rehabilitation and Compensation Act 2004 (MRCA) that rely on the reasonable hypothesis standard of proof (sections 120A VEA and 338 MRCA). The instrument does not create new law about what influenza is or how it is treated; rather it codifies the medical-scientific evidence threshold that the Authority considers necessary for the causal connection to be plausible. Section 9 lists six independent factors, any one of which suffices: exposure to influenza virus as specified within the three weeks before clinical onset (subsection 9(1)); for avian influenza only, exposure to an avian influenza virus as specified within that window (subsection 9(2)); for swine influenza only, exposure to a swine influenza virus as specified within that window (subsection 9(3)); inability to obtain influenza vaccination between ten days and six months before clinical onset (subsection 9(4)); for severe influenza only, having a specified medical condition at the time of onset or being in the third trimester of pregnancy or within six weeks postpartum (subsection 9(5)); or inability to obtain appropriate clinical management for influenza (subsection 9(6)). Each factor under section 9 must itself be related to the person's relevant service (section 10(1)). The factor about inability to obtain clinical management applies only to material contribution to, or aggravation of, influenza that was suffered or contracted before or during (but did not arise out of) service (section 10(2)). The instrument thus replaces a broader, unstructured inquiry with a closed list of evidentiary pathways. This standardisation reduces arbitrariness but also restricts the range of circumstances a tribunal or decision-maker may consider. Claimants cannot rely on a generic "I caught flu on base" claim unless they fit within one of the tightly defined exposure categories or the vaccination or clinical management exceptions. The practical effect is to raise the evidentiary bar, especially for cases where the precise source of infection is unknown or undocumented.

The instrument defines several key concepts that determine its scope and operation. Influenza means an acute respiratory tract infection due to the influenza virus (an RNA virus of the Orthomyxoviridae family, types A, B or C), characterised by fever, cough, shortness of breath, headaches, myalgia, conjunctivitis and pneumonia; it includes infection with human and animal influenza subtypes (section 7(2)). The definition does not depend on the ICD-10-AM code assigned, though codes J09, J10 or J11 are mentioned (section 7(3)). Death from influenza includes death from a terminal event contributed to by influenza,terminal event being pneumonia, respiratory failure, cardiac arrest, circulatory failure, or cessation of brain function (Schedule 1 dictionary). Clinical onset is not defined here but is a standard concept in veterans' SoPs meaning the point at which a person first manifests symptoms of the disease. Relevant service is defined exhaustively for VEA purposes as operational, peacekeeping, hazardous, or British nuclear test defence service; under MRCA as warlike or non-warlike service (Schedule 1). This means the instrument does not apply to peacetime defence service that is not within those categories unless MRCA covers it by the "defence service" definition elsewhere. Close exposure is defined as direct physical contact or being within two metres (Schedule 1). This is a specific spatial test; being in the same building but beyond two metres is not close exposure unless the broader household/work/travel environment provision for human influenza virus applies (paragraphs (a)-(c) of "being exposed to influenza virus as specified"). For human influenza virus, being in the same household or immediate work or travel environment as a person who has influenza counts as exposure without requiring proof of two metres physical proximity. For avian and swine influenza, different exposure pathways are listed, involving contact with infected animals, products, contaminated surfaces, or laboratory strains. Severe influenza means influenza complicated by pneumonia, lower respiratory tract infection, myocarditis, pericarditis, myositis, rhabdomyolysis or neurological complications; or influenza requiring hospitalisation; or death from influenza (Schedule 1). Medical condition as specified is a closed list of ten conditions: asthma, cardiovascular disease (excluding isolated hypertension), chronic lung disease (including bronchiectasis and COPD), diabetes mellitus, immunocompromised state as specified, liver disease, morbid obesity, neurological disease (including epilepsy, neuromuscular and neurocognitive disease), renal disease, or sickle-cell disorder (Schedule 1). is itself defined as a condition of substantially lowered immune function from HIV infection, immunosuppressive drug treatment, haematological or solid organ malignancy, chronic renal failure (with a specific definition based on GFR or dialysis), severe malnutrition, or solid organ/stem cell/bone marrow transplantation. and are not further defined in the instrument; they are fact-based thresholds that will require evidence of absence of access rather than mere failure to seek care.

The instrument directly affects three broad groups. First, claimants: veterans who rendered operational, peacekeeping, hazardous, or British nuclear test defence service under the VEA, and members who rendered warlike or non-warlike service under the MRCA (section 10 and definition of relevant service in Schedule 1). It also affects dependants or estate representatives claiming in respect of a deceased person whose death is linked to influenza. The instrument applies to claims where the reasonable hypothesis standard applies (section 5). Second, decision-makers: the Repatriation Commission, the Military Rehabilitation and Compensation Commission, the Veterans' Review Board, and the Administrative Appeals Tribunal must apply these factors when assessing claims. The instrument binds them because it is made under statutory authority and is a legislative instrument. Third, medical advisers and advocates: practitioners providing evidence for claims need to know the specific definitions of exposure, close exposure, severe influenza, and medical condition as specified to frame reports that address the factors. The instrument indirectly affects healthcare providers if a claimant argues inability to obtain clinical management: the availability of appropriate treatment in service or post-service becomes relevant. However, the instrument does not impose duties on third parties; it only specifies conditions for entitlement. The concentrated benefit goes to claimants who can satisfy a factor; the diffuse cost falls on taxpayers and the veterans' compensation system through claims that might not have succeeded under the previous, broader SoP or under no SoP at all. The instrument also narrows the range of potential claimants compared to a hypothetical no-SoP regime, because the factors are more restrictive than the general common sense inference that service in crowded barracks increases infection risk. By requiring specific exposure events or vaccination inability, the SoP raises the evidentiary burden. Claimants who contracted influenza from an unknown source in the community while on leave, but whose service-related stress or living conditions made them more susceptible, may have no path unless they meet the "medical condition as specified" factor for severe influenza. The instrument also affects those with avian or swine influenza separately: paragraphs 9(2) and 9(3) require exposure to those specific virus subtypes, which may be rare in typical Australian military service but could arise in deployments or laboratory work.

The instrument does not create duties on individuals; rather it defines the rights of claimants to have a claim accepted if they raise a reasonable hypothesis. The core right is that a claimant who points to at least one factor in section 9, and demonstrates that the factor is related to their relevant service, is entitled to have the claim determined on the basis that a reasonable hypothesis exists. The decision-maker then has a duty to accept that the hypothesis is reasonable unless the contrary is proved beyond reasonable doubt (under VEA section 120(3)). The instrument therefore shifts the evidentiary burden: once a claimant shows a factor, the decision-maker cannot dismiss the claim on the ground that the hypothesis is not medically plausible, unless they have evidence disproving it. The duty of the Repatriation Medical Authority is to keep these SoPs under review and to determine factors based on sound medical-scientific evidence (section 8 states the Authority is of the view that such evidence exists). The duty of the decision-maker is to apply the dictionary definitions strictly, especially "close exposure", "influenza virus", "immunocompromised state as specified", and "medical condition as specified". There is no discretion to treat an equivalent condition not listed as satisfying the factor; the lists are exhaustive. Claimants have a right to rely on section 11, which provides that if a factor refers to another injury or disease covered by a separate SoP, the factors in that other SoP apply. This cross-referencing mechanism means that a claimant cannot satisfy a factor like "having a medical condition as specified" by showing they have a condition like asthma unless the asthma itself can be related to service under its own SoP. In practice, this chains the entitlements: the influenza claim may depend on a prior accepted condition. The instrument also gives claimants a right to have the old SoP (No. 58 of 2009) no longer applied, as it is revoked (section 4). That revocation may disadvantage a claimant who would have satisfied a factor under the old SoP but not the new one; however, section 5 only applies to claims to which section 120A VEA or section 338 MRCA applies, so transitional provisions in those Acts govern which SoP applies based on claim lodgement date. The instrument does not create any right to vaccination or clinical management; it only uses inability to obtain them as a factor. This implicitly discourages any claim that relies on the personal choice not to be vaccinated, because "inability" suggests objective unavailability, not personal decision.

This instrument does not contain penalties. Enforcement occurs within the claims and review framework of the VEA and MRCA. A claimant who knowingly provides false or misleading evidence regarding exposure, vaccination availability, or clinical management may face penalties under the Criminal Code or the VEA (section 137 of the VEA for false statements). However, the instrument itself only sets evidentiary standards; it does not create offences. The primary enforcement mechanism is the refusal of a claim if the factors are not met. If a decision-maker incorrectly applies the SoP, the claimant may seek review by the Veterans' Review Board and then the Administrative Appeals Tribunal, and ultimately the Federal Court on questions of law. The SoP has the force of a legislative instrument, so a decision-maker who disregards it commits an error of law. The compliance burden falls on claimants to produce evidence of the factor. For exposure factors, this may require obtaining records of known infected contacts, laboratory reports, or other documentation of the environment. For inability to obtain vaccination, the claimant must show that the vaccine was not available in a timely manner, not merely that they chose not to get it. The burden may be substantial for exposure occurring decades ago, especially if the specific virus subtype or close contact is not documented. The Repatriation Medical Authority itself has no enforcement role once the SoP is made; its duty is to determine and revoke SoPs under Part IIA of the VEA. The instrument has an indirect enforcement effect on medical practitioners who provide expert opinion: they must engage with the defined terms, not just give general causation evidence. An opinion that does not address the factors may be given little weight by the tribunal. The instrument does not provide for any penalty for non-compliance by a third party, because it is not directed at third parties.

The SoP sits within the broader framework of veterans' and military compensation legislation. It is made under section 196B(2) of the VEA, which requires the Repatriation Medical Authority to determine SoPs for kinds of injury, disease or death. The instrument replaces the earlier SoP No. 58 of 2009 (section 4). It does not amend the VEA or MRCA themselves but operates as a subordinate legislative instrument. Section 11 creates an important interaction with other SoPs: if a factor in section 9 refers to an injury or disease for which another SoP exists, the factors in that other SoP are incorporated. For example, if a claimant relies on having a "medical condition as specified" such as asthma, and the asthma itself is not already accepted as service-related, the claimant must also satisfy the SoP for asthma (if one exists) to establish the condition. This means the influenza claim may be contingent on a separate claim for the underlying condition. The instrument defines "relevant service" by reference to VEA categories (operational, peacekeeping, hazardous, British nuclear test defence) and MRCA categories (warlike, non-warlike). It does not apply to peacetime service under the VEA (which uses a different standard of proof, reasonable satisfaction). The SoP interacts with the standard of proof provisions: section 120A(3) VEA and section 338(3) MRCA require that a reasonable hypothesis be raised in accordance with the relevant SoP. Thus, if the factors in this SoP are not met, no reasonable hypothesis exists as a matter of law, regardless of medical intuition. The SoP also interacts with ICD-10-AM coding: section 7(3) states that while influenza attracts codes J09-J11, the definition is that in subsection (2), not the code. This prevents a purely administrative code from dictating the medical meaning. The interaction with the VEA's definition of "injury" and "disease" is indirect: influenza is a disease, and death from influenza is covered. The instrument does not address causation for conditions that influenza may aggravate, except through the severe influenza factor which lists complications. If a claimant has a separate SoP for a condition like pneumonia, the death from influenza may also need to satisfy the pneumonia SoP if the terminal event is pneumonia. The instrument is silent on overlap with workers compensation or private insurance; it only applies to the specific Commonwealth schemes.

This instrument is made on 18 August 2017 and commences on 18 September 2017. It revokes the Statement of Principles concerning influenza No. 58 of 2009 made under the same subsection 196B(2) of the VEA. The source text does not disclose any intermediate amendments between the 2009 and 2017 versions, nor does it list any amendments after commencement. The instrument itself has no amendment history within its text; it is the current version as made. However, the Repatriation Medical Authority regularly reviews and updates SoPs as medical evidence changes. Users should check the Federal Register of Legislation for any subsequent amendments or replacements. The revocation of No. 58 of 2009 suggests that the medical-scientific evidence on influenza and service-relatedness has advanced sufficiently to warrant a new set of factors. The main changes from the 2009 version are not specified in the source, but the structure and definitions are likely updated to reflect current epidemiology, including the separate treatment of avian and swine influenza. Practitioners should not rely on the old instrument for claims lodged after 18 September 2017, as section 5 limits application to claims under sections 120A or 338, and the transitional provisions in the VEA and MRCA will determine which SoP applies to claims lodged before commencement but decided after. The instrument does not include a provision for retrospective commencement; it commences on 18 September 2017, which is 31 days after making.

The source text does not reference any litigation history, nor does it name any court or tribunal decisions. This is typical for a Statement of Principles; they are made by an administrative body and are not themselves subject to appeal. However, SoPs can be challenged in the Federal Court on grounds such as ultra vires or jurisdictional error. No such challenge is recorded in the instrument. In practice, the interpretation of SoP terms such as "close exposure" and "inability to obtain vaccination" has been considered in decisions of the Administrative Appeals Tribunal and the Federal Court. For example, the phrase "inability to obtain" has been held to mean genuine unavailability rather than personal choice, though that is a general principle of administrative law not unique to this SoP. The earlier SoP No. 58 of 2009 may have been litigated, but this instrument has been in force since 2017 and any decisions under it are not listed in the source. Claimants and advocates should search the AustLII database for decisions referencing "Statement of Principles concerning influenza (Reasonable Hypothesis) (No. 44 of 2017)" for relevant tribunal determinations. The absence of recorded litigation in the instrument itself does not imply that the SoP is uncontroversial; it may simply reflect that most claims are resolved at the primary level or that the factors are sufficiently clear to discourage appeals. The instrument's definitions of "close exposure" (two metres) and the exhaustive list of medical conditions are likely to give rise to disputes about whether particular contact or conditions fall within the definitions.

Several features of the instrument can catch out claimants and practitioners. First, the time windows are tight. The three-week window for exposure before clinical onset (section 9(1)-(3)) means that any exposure outside that period, even one that clearly caused infection, will not raise a reasonable hypothesis under this SoP. For example, exposure four weeks before onset falls outside the factor. The vaccination factor requires inability to obtain vaccination between ten days and six months before onset. Inability within ten days of onset does not count, nor does inability more than six months before. Second, "inability to obtain" vaccination or clinical management is a high bar. It is not the same as failure to offer or failure to seek. The claimant must show that the vaccine was genuinely unavailable in the circumstances of their service, not that they chose not to be vaccinated. For clinical management, the claimant must show that appropriate care was not obtainable, not merely that care was inadequate or delayed. Third, the severe influenza factor (subsection 9(5)) only applies if the influenza is severe as defined. If the claimant had ordinary influenza without complications or hospitalisation, this factor is unavailable even if they had a specified medical condition. The medical condition must exist at the time of clinical onset of influenza; a condition that develops later is irrelevant. Fourth, the list of medical conditions in the dictionary is closed. Obesity is only morbid obesity; ordinary obesity does not qualify. Neurological disease includes epilepsy, neuromuscular and neurocognitive disease, but not, for example, migraine unless it is neurocognitive. Immunocompromised state as specified is also closed: it includes HIV, immunosuppressive drugs, malignancy, chronic renal failure, severe malnutrition, and transplant, but does not include, for instance, poorly controlled diabetes even if it impairs immunity. Fifth, the close exposure definition (two metres direct physical contact) is strict. For human influenza, "being in the same household, or immediate work or travel environment" is also available (paragraph (c) of "being exposed to influenza virus as specified"), but note that this only applies for human influenza virus; for avian or swine influenza, close exposure must be within two metres or physical contact. Sixth, the instrument does not cover seasonal influenza that cannot be linked to a known infected person or animal. If the claimant was exposed in a barracks but cannot identify a specific infected individual, they may not meet the definition because they cannot show close exposure to a person infected with influenza virus. The household/work/travel environment provision requires a person who has influenza - not anonymous exposure. Seventh, the factor (subsection 9(6)) only applies to aggravation of pre-existing influenza (section 10(2)). If influenza arose out of service, this factor cannot be used. Eighth, the cross-reference in means that if the claimant relies on a medical condition such as asthma, they must also satisfy the SoP for asthma (if one exists) to have that condition considered factually established. A mere diagnosis is insufficient. Ninth, the instrument revokes the old SoP, but transitional provisions in the VEA mean that some claims may still be decided under the old instrument if lodged before commencement. Tenth, the includes animal subtypes but the exposure factors for avian and swine are separate and require that the virus be specifically that subtype; if someone is exposed to a pig infected with human influenza, the swine influenza factor may not apply because the virus is not swine influenza virus as defined.

For a claimant seeking to rely on this SoP to establish a reasonable hypothesis linking influenza or death from influenza to relevant service, compliance requires assembling evidence that fits within one or more of the section 9 factors. The most common pathway is factor 9(1) - exposure to influenza virus as specified. The claimant should obtain evidence of close exposure to or direct contact with a person or animal infected with influenza virus within the three weeks before symptoms started. For human influenza, "being in the same household, or immediate work or travel environment, as a person who has influenza" is easier to prove than a specific two-metre encounter. Records of outbreaks, medical certificates from the infected person, or contemporaneous reports of symptomatic contacts will help. If the exposure was to avian or swine influenza, the specific exposure categories in paragraphs 9(2) and 9(3) must be met and the virus subtype identified (this may require laboratory confirmation, which is rare). Factor 9(4) - inability to obtain influenza vaccination - requires evidence that no vaccine was offered or available between ten days and six months before onset. This may be proven by service records showing vaccination was not administered and was not obtainable in the location. A mere failure to offer is not enough if the claimant could have sought it; the inability must be objective. Factor 9(5) - severe influenza with a medical condition as specified - requires two proofs: that the influenza was severe (complicated by the listed conditions or requiring hospitalisation), and that the claimant had one of the listed medical conditions at the time of onset. Medical records should document both. The listed medical condition must itself be established; if it is not already accepted as service-related, the claimant may need a separate SoP to support it. Factor 9(6) - inability to obtain appropriate clinical management - applies only where influenza was suffered or contracted before or during service but did not arise out of service (section 10(2)). This factor is useful for aggravation claims. Evidence must show that appropriate treatment was not obtainable, not just that it was delayed or suboptimal. For all factors, evidence must relate the factor to the person's relevant service (section 10(1)). For example, exposure must occur during or as a consequence of service. Vaccination unavailability must be because of service circumstances (e.g. deployed to a location without vaccine). Medical conditions must be connected to service under their own SoP. Claimants should obtain a report from a medical practitioner who is familiar with the SoP and can address each relevant definition. The report should state the clinical onset date, the nature of exposure (with distance, duration, and environment), the virus subtype if unusual, and details of vaccination or clinical management. For death claims, the terminal event must be identified and linked to influenza. The decision-maker will apply the definitions strictly, so precise language matters: "close exposure" should be quantified. The dictionary definitions are mandatory; using synonyms could result in the factor not being met. If the claim involves multiple factors, the strongest evidence should be emphasised. Claimants should also be aware that factor 9(5) applies only to severe influenza; if the influenza was not severe, that factor cannot be used even if they had a severe medical condition.