Infections, bioterror a growing global threat

WHO says prepare for natural to defeat intentional

More than at any previous time in history, global public health security depends on international cooperation and the willingness of all countries to meet the threat of rapidly emerging infectious diseases and acts of bioterrorism, the World Health Organization emphasizes in a new report. New health threats include potential terrorist attacks, chemical incidents and radionuclear accidents, the WHO warns.

The WHO has participated in international discussions and bioterrorism desktop exercises, arguing that the surest way to detect a deliberately caused outbreak is to strengthen the systems used for detecting natural outbreaks, as the epidemiological and laboratory principles are fundamentally the same, the report states. As an example of how overwhelmingly disruptive a bioterrorism attack can be, the WHO report cites the 2001 anthrax mail attacks in the United States. "Coming only days after the terrorist events of 11 September 2001 in the United States, the deliberate dissemination of potentially lethal anthrax spores in letters sent through the United States Postal Service added the deliberate release of biological or chemical agents to the realities of life in the 21st century," the WHO said.

To recap, anthrax spores were found in only four envelopes, but the impact was staggering. "In addition to the human toll — five people died among 22 cases — the anthrax attack caused massive disruption of postal services in many countries around the world and had huge economic, public health and security consequences," the WHO reported.

For years, the United States and other industrialized countries had lived with the fear — frequently fed by hoax calls and alarms — of just such an attack. Although there was no evidence that they had been used, it was well known that stocks of biological weapons, including anthrax, were held by a number of countries.

"Effective medical measures for prevention and treatment of the two forms of the disease — cutaneous and inhalational anthrax — were established and published in the medical literature well before the anthrax letter attacks. Nevertheless, the anthrax letters . . . caused huge public alarm and prompted a massive public health response. . . . Drugs were made available on an emergency basis to some 32,000 people who were potentially exposed. Altogether, about 3.75 million antimicrobial tablets were distributed."

The collection and testing of environmental and clinical samples, as well as materials from suspicious incidents and hoaxes, placed an immense burden on the CDC, public health laboratories throughout the country and government agencies. One legacy of the crisis was the introduction of permanent decontamination, detection, and security equipment at mail processing facilities across the country, the WHO noted. To reduce potentially contaminated dust and aerosols from the atmosphere in its centers, the Postal Service introduced some 16,000 high-efficiency particulate air filter vacuum machines and, as a precaution, routinely sterilizes mail going to federal agencies by electron-beam irradiation. For the two fiscal years 2003 and 2004, $ 1.7 billion in was budgeted for additional modifications and improvements in the government's ability to protect the health of postal workers and to prevent pathogens and other hazardous substances from being distributed through the mail.

'Even though the deliberate release of the anthrax was directed at one country, it had regionwide effect in the Americas," the WHO reported. "This was especially so as public health infrastructures had to divert resources to face an overwhelming demand for laboratory tests for suspected tainted postal items, personal protective equipment and for the decontamination of facilities."

Occurring as it did so soon after the September 2001 terrorist attacks, the anthrax offensive prompted a profound rethinking of threats to national and international security. It showed the potential of bioterrorism to cause not just death and disability, but social and economic disruption on an enormous scale both in the United States and internationally, the report states.

"In our increasingly interconnected world, new diseases are emerging at an unprecedented rate, often with the ability to cross borders rapidly and spread," the report states. "Since 1967, at least 39 new pathogens have been identified, including HIV, Ebola hemorrhagic fever, Marburg fever, and SARS. Other centuries-old threats, such as pandemic influenza, malaria and tuberculosis, continue to pose a threat to health through a combination of mutation, rising resistance to antimicrobial medicines and weak health systems."

Global airlines now carry more than 2 billion passengers a year, enabling people and the diseases that travel with them to pass from one country to another in a matter of hours, the WHO noted. The potential health and economic impact was seen in 2003 with SARS, which cost Asian countries an estimated $60 billion in U.S. dollars. The report also sets out the WHO strategic action plan to respond to a pandemic, draws attention to the need for stronger health systems and for continued vigilance in managing the risks and consequences of the international spread of polio and the newly emerging strain of extensively drug-resistant TB (XDR-TB). Noting that no nation is safe in isolation, the WHO urges the following actions for all countries:

  • global cooperation in surveillance and outbreak alert and response;
  • open sharing of knowledge, technologies and materials, including viruses and other laboratory samples, necessary to optimize secure global public health;
  • global responsibility for capacity building within the public health infrastructure of all countries;
  • cross-sector collaboration within governments; and increased global and national resources for training, surveillance, laboratory capacity, response networks, and prevention campaigns.

The WHO report is available on the web at: www.who.int/whr/2007/en/index.html.