Infectious Diseases and U.S. National Security

How disease cripples armed forces and threatens global security


Militaries and infectious diseases have always been intertwined. History records hundreds of armies crippled by disease. In his account of the Peloponnesian War, Thucydides describes the devastation of a wartime plague on the Athenian people and leadership. German General Erich Von Ludendorff blamed the 1918 Spanish flu pandemic for failure of his spring offensive and ultimately contributing to the Allied victory. However, after World War II the strategic implications of infectious disease on national security were overlooked. Instead security and foreign policy communities primarily focused on the nuclear tension between the United States and the Soviet Union. National security under the Cold War paradigm was the “preservation of the state – its territorial integrity, political institutions, and national sovereignty – from physical threats”.

After the Cold War, attempts were made to expand the concept of security into new areas including economic, societal, and health security. The concept of human security has made particular headway. Human security was first posited in the 1994 United Nations Human Development Report and argues security must be redefined in terms of the individual rather than the state. The report lists a number of threats to individuals from famine to environmental destruction. However, while human security’s expanded definition has been useful, it is unnecessary in the present discussion. Infectious diseases are also threats in state-centric notions of national security. Diseases can weaken the capacity of militaries in developing states where Western nations have significant enough national interest to respond to internal, external, and regional threats. Securing these states would place additional burdens on resources, but the global risk from new and reemerging infectious diseases continues to rise in the 21st century, with significant implications for global and regional security.


The Growing Importance of Infectious Diseases

The middle of the 20th century saw rapid progress in fighting various diseases. Experts believed new technology had stemmed the spread of many infectious diseases in the developed world and lent hope of high levels of health worldwide by the end of the millennium. However, recently new infectious diseases have emerged and once-controllable diseases have mutated and developed drug resistance.

Globalised trade, a growing and more mobile population, and widespread urbanisation resulted in emerging and reemerging infectious diseases spreading rapidly at the turn of the century. This “third wave” of infectious diseases – including HIV, cholera, and tuberculosis – have become a significant threat. The 2000 US National Intelligence Estimate classified infectious disease for the first time as a threat to national security, warning, “new and reemerging infectious diseases will pose a rising global health threat and will complicate US and global security.” Infectious diseases in the future will thrive in an ever more interconnected, mobile, and crowded world. 

The impact of infectious disease has struck hardest in the developing world, where poverty, conflict, and weak institutions leave states vulnerable. As a result, infectious diseases pose the greatest threat to developing states and their militaries. How might infectious diseases weaken the militaries of developing states? Where are they most vulnerable? A strong case study through which to examine these questions is the tragic and ongoing problem of HIV/AIDS in African militaries.


Devastating Impact

Few doubt the devastating effect of HIV/AIDS on African militaries.  In 2007, around 22 million Africans were infected by the HIV-2 strain, representing two-thirds of worldwide infections.  In seven Southern African states, HIV prevalence exceeds 15%.

Militaries personnel are at particular risk of HIV infection, with the majority of recruits between 18 and 24 years old, sexually active, and experiencing long deployments away from traditional social networks amid a military culture that promotes aggression, machismo, and risk taking.

The precise figure is debated but some armed forces are rumored to have HIV prevalence rates over 50%. The South African National Defense Force (SANDF) admits between 10% and 12% of military personnel are HIV-positive, a range many consider conservative. In 2004, China rejected one-third of Zimbabwean officers for advanced training due to their HIV status.  HIV prevalence rates in African militaries are unknown or – in some cases – classified as state secrets.  However, it is reasonable to assume HIV rates are at least comparable to the state’s civilian population and thus high enough to weaken African militaries in numerous ways:

Smaller Recruitment Pool – Recruits who are HIV-positive are seen as less suitable for military service. In response to high HIV prevalence in the general population some African militaries conduct pre-employment testing. However, testing can cause prospective recruits to self-select out of military service, shrinking the recruitment pool and reducing the overall quality of the armed forces.

Loss of Experienced Personnel – The effects of HIV/AIDS are felt all along the chain of command. Half of the Malawian general staff, for example, has been rumored to be HIV positive.  South Africa is facing rising HIV prevalence in young blacks while ‘fast tracking’ young black officers into mid-level positions.  Experienced officers take decades to train and develop, making them one of the military’s most valuable resources. The loss of experienced personnel to HIV/AIDS erodes African militaries of their organisational capacity and institutional knowledge.

Reduction in Effectiveness – High infection rates weaken the ability of African militaries to operate effectively.  Military personnel with AIDS are less able to complete physically demanding tasks, are more susceptible to adverse conditions during deployments, and have lower morale. Furthermore, individuals unable to perform their duties must be transferred to less demanding roles, reducing the capacity of the military to deploy homogenous units.

Greater Financial Burden – African armed forces are primarily reliant on their human resources. However, the mounting financial costs of personnel with HIV/AIDS drains the financial resources of African militaries. Militaries with high HIV prevalence have less financial resources available for their core functions. Professor Lindy Heinecken of South Africa's Stellenbosch University has called this the “biggest challenge” for the SANDF.

Reduced Peacekeeping Capacity – HIV/AIDS weakens the ability of African armed forces to participate in regional peacekeeping operations. According to one account, at the start of the new millennium, the high prevalence of HIV in African armed forces hampered the United Nations’ capacity to fulfill the demand for peacekeepers on the continent. The epidemic undermines peacekeeping capacity in three ways. First, HIV/AIDS is making states reluctant to contribute peacekeepers. One study found HIV prevalence among peacekeepers in Sierra Leone rose from 7% to 15% during a three-year deployment.  Faced with the positive correlation between peacekeeping and HIV prevalence, African states are less willing to contribute forces to peacekeeping operations. Second, high HIV prevalence reduces the ability of African armed forces to deploy peacekeepers. The combination of a high HIV-prevalence among SANDF personnel and a policy of excluding HIV-positive troops from UN peacekeeping duty means that a significant portion of troops are unavailable for deployment.  A 2003 RAND study reported that one South African official supposedly claimed that HIV/AIDS was the primary reason South Africa has not been more involved in the conflict in the Democratic Republic of the Congo.


Implications For US National Security

The specific effects and risks to a nation’s military are unique to individual infectious diseases. However, the case of HIV/AIDS in African armed forces offers general insights into the potential effects of infectious diseases on the militaries of developing nations, with implications for the national security of Western countries, who have the capacity to help address some of these concerns.

Infectious diseases can threaten the domestic security and stability of developing nations where Western nations have significant national interest. Armed forces are often called upon to maintain domestic security. Militaries crippled by HIV/AIDS are less able operate in this capacity. Governments unable to maintain domestic security could be perceived as less legitimate by the civilian population and increase popular support for non-state armed opposition groups. Thus, the demands placed on armed forces to protect against domestic threats would be likely negatively related to the military’s own effectiveness.

Militaries of developing nations heavily burdened by infectious diseases are vulnerable to external threats. Regional stability is maintained by a balance of power. Shifts in the power dynamic among states increase the risk of interstate war. Militaries of developing nations weakened by infectious diseases are less able to deter international aggression. Some have argued that even the perception of security vulnerability from infectious diseases could trigger opportunistic invasion. Western nations have an interest in maintaining regional stability, not only for normative reasons, but also to protect strategic or economic national interests in the area.

Infectious diseases could limit a state’s capacity to conduct peacekeeping operations. States with militaries debilitated by infectious diseases would be less able to muster an effective peacekeeping force from their reduced ranks. Even if a military had the capacity to contribute peacekeepers, the state might be reluctant to deploy them and stretch their already thinning ranks. Furthermore, states hosting peacekeeping forces could resist the presence of infected troops and the resultant risk of spreading the disease to their citizens.  As infectious diseases reduce a state’s peacekeeping capacity the burden could increasingly fall on the United States and its Western allies to maintain regional stability or risk wider conflicts.


Infectious Disease and US National Security Policy

In the 21st century, infectious diseases are increasingly a serious threat to global security. In particular, Western programmes to strengthen the effectiveness of developing world security forces must also increase their health capacity and the ability of friendly foreign armed forces to respond to infectious diseases within their ranks. The framework for such programmes already exists. The United States’ African Contingency Operations Training and Assistance programme boosts the capacity of African militaries to conduct peacekeeping and humanitarian missions on the continent. Its greatest challenge, according to one commentator, is that the HIV/AIDS epidemic is crippling the participating militaries before they can be effectively deployed.  Enlarging the role of health capacity building in this and similar programmes offers a means to make friendly militaries more resistant to infectious disease, increasing their ability to provide domestic, international, and regional stability.


Acknowledgment: an earlier version of this essay was published as “Infectious Disease, Foreign Militaries, and US National Security,” chapter in Michael Tanji (ed.), Threats in the Age of Obama, (Nimble Press, 2009).



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