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Biological Threats

Frequently Asked Questions


What agents or chemicals are most likely to be used in a terrorist attack?

It is important to remember that the likelihood of a terrorist attack in Canada using biological or chemical agents is very remote. Regarding the agents most likely to be used in the event of such an attack, Canada and the United States have agreed on a list of top bioterrorist agents, including anthrax, smallpox, plague, tularemia, botulism and certain viruses that cause viral haemorrhagic fevers. Of the biological agents examined, anthrax is the most likely to be used in a bioterrorist attack. Tularemia or plague is a low probability, botulism is lower still, and both smallpox and the viral haemorrhagic fever agents were assessed a very low probability.

How easily can they be spread into the population?

The knowledge required and technology needed to develop and spread these agents in a bioterrorist attack is very difficult and complicated.

  • For technical reasons related to the agent, the introduction of tularemia (rabbit fever), plague and the viral haemorrhagic fevers into the population, and their subsequent spread, is very unlikely to occur.
  • The botulinum toxin is also difficult to introduce into a large population and does not spread person to person.
  • Smallpox can be spread from person to person, but people ill with smallpox are generally very sick and are usually confined to their beds. They are unlikely to be able to travel in public. Since its eradication in 1977, world experts feel that its containment makes smallpox a very unlikely bioterrorism agent and that its introduction into a population would be very difficult to achieve. All countries agree, however, that even a single case of smallpox anywhere in the world would be an international health emergency. In this event, all nations would respond to contain and prevent spread of the infection.
  • Anthrax, as events in the United States demonstrate, can be introduced into wide circulation by apparently innocuous means. While recognizing the level of public concern, and the suffering and loss of those people infected and ill with anthrax, it is still important to point out that despite the widespread environmental findings of anthrax, relatively few people have been infected. With early detection and rapid medical intervention, most, if not all, cases of exposure to anthrax spores can be treated and disease and illness prevented.

Is there a vaccine for anthrax?

Yes, but the current vaccine has side effects, requires multiple doses and needs to be repeated frequently to provide any level of protection. It is currently not available to the general public, and is used only in very high-risk situations, such as expected exposure during military operations.

Can I take antibiotics ahead of time to prevent the possibility of getting anthrax?

There are several potential down sides to this approach. The greatest risk is that exposure to anthrax spores cannot be accurately predicted. If a large segment of the population takes antibiotics to prevent infection, this could lead to an increased risk of side effects and could also result in the possible drug resistance of the bacteria. The unnecessary use of antibiotics could also lead to a shortage should the drugs be needed for the treatment of infections. For these reasons, the use of antibiotics ahead of time is not recommended.

Canadians were vaccinated against smallpox before the 1970s. Would those people still have immunity against smallpox now?

Some Canadians born before the 1970s, but not all, were vaccinated against smallpox. Anyone born in the 1970s and later is unlikely to have been vaccinated against smallpox. Some protective immunity may persist in those people previously vaccinated. In people previously vaccinated, immunity can be effectively boosted with re-vaccination.

Is Canada planning a mass immunization campaign against smallpox? If not, why not?

A single dose of smallpox vaccine, even given up to 4 days after exposure to smallpox, can prevent serious illness and death from smallpox. For this reason, and because the smallpox vaccine itself can cause severe illness and even death following immunization, mass immunization campaigns against smallpox are not recommended. A small supply of the vaccine is available in Canada, and would be used to contain and prevent illness around a detected case of smallpox if a case were to occur. Globally, supplies of smallpox vaccine are either currently available, or would be made available, to prevent smallpox disease in any area of the world.

Is our drinking water safe from contamination?

Water treatment would usually prevent the spread or destroy the potential agents of terrorism discussed above. Deliberate contamination of a water source as an act of large-scale terrorism is very unlikely to occur, and even more unlikely to be successful.

What if terrorists take a flu strain or other infectious disease and manipulate it to make a killer flu? What is the likelihood of that happening?

Genetic manipulation of biological agents to make them "weapons grade" requires significant technological support, and it is generally believed that this would need to be sponsored by the finances of an international government or state. Although this type of global attack could be possible, international safeguards are in place to prevent and detect any rogue efforts to develop biological weapons of mass destruction of this nature.

Do gas masks protect you from terrorist or chemical attacks?

Depending on the biological or chemical agent and the method used to expose people, a mask may provide some benefit (e.g. from anthrax spores), but there are several conditions that must be met before protection would occur. The mask must be properly designed and fitted, it must be used properly, and people would have to be instructed and monitored on when and when not to wear it. Gas masks found in many surplus supply stores would not provide adequate protection against an inhaled biological agent.

How secure is the Winnipeg laboratory against possible terrorist attacks?

On September 11, 2001, an unthinkable and hence an unanticipated attack occurred in the United States using airplanes as terrorist devices. As a result, the physical security surrounding potential targets in Canada has been enhanced, including the security at the Winnipeg laboratory.

The National Microbiology Laboratory is specifically designed to be able to work with the most dangerous biological pathogens known. A biological, chemical, radionuclear threat or a physical attack against this facility is very unlikely.

Two highly effective security systems are in place at the laboratory to protect those working in the facility and in the neighbouring community. One security system prevents unauthorized access to the facility. This security system was formulated in consultation with the RCMP and the Canadian Security and Intelligence Service (CSIS).

A second security system ensures the biological safety and integrity of the laboratory. This system is recognized as being of the highest order and the systems in place are regarded as the benchmark for other laboratories in the world to achieve.

How secure is the Winnipeg laboratory in the event that there's a leak of dangerous materials from inside the lab into the surrounding neighbourhood?

Level 3 and 4 laboratory areas contain airtight rooms and duct work, and feature interlocking and airtight bio-seal door and damper systems. Air-locks for entry and exit maintain negative air pressures to direct air inward, ensuring that organisms being studied remain in the laboratory.

What is the Government of Canada doing to ensure that Canada's monitoring and surveillance system can quickly identify any unusual disease outbreaks or detect contaminants in food?

Through provincial and territorial partnerships in public health and disease surveillance, all levels of government in Canada are confident that the appropriate early warning systems are available to protect the health of Canadians.

Describe what happens to a suspicious package from the time it's found, say in a mail room, to the time it gets to the Winnipeg laboratory for testing.

When a package, or other material, raises suspicion, the first step is to address the suspicion. It is recommended by Health Canada that the following steps be taken when such a situation arises.

First, the person exposed must immediately leave the package, clear the area of all people to a safe distance, and wash any potentially exposed skin. Next, the police or other appropriate authority must be immediately alerted.

These specially trained individuals will assess the level of suspicion by containing the affected area and taking a sample of the unknown material. The material is then wrapped according to standards for packaging and transporting dangerous goods and transported to the nearest laboratory capable of testing the sample in a safe and secure environment.

If the test results are positive and the material requires further examination, the material would be repackaged according to the same standards for transportation of dangerous goods and sent to Health Canada's National Microbiology Laboratory in Winnipeg for additional testing.