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Preparedness Tips from the Center for Civilian Biodefense Strategies


On March 17, the federal government raised the homeland security threat level to “orange" (White House statement). Public concern regarding potential terrorist attacks has become elevated, and many people are looking for bioterrorism-related information.

The Johns Hopkins Center for Civilian Biodefense Strategies has prepared answers to the following frequently asked questions about bioterrorism. 

Does it make sense for me to put together an emergency family plan and supply kit? 

Yes. There are some helpful checklists of actions to take during normal times that will allow you to act more effectively during a crisis.

Some simple steps, such as devising a plan for getting in touch with family members after a disaster, are useful whether the event is a terrorist attack or something more common such as a hurricane, tornado, flood, or snowstorm. 

You should recognize, however, that some preparedness items or actions that could prove valuable in some emergency situations might not be useful in the special case of bioterrorism. Bioterrorism is different from terrorist attacks that involve explosives or chemicals.

How will I know when a terrorist attack has occurred and what I should do to protect my family and myself?

A bioterrorist attack is likely to be covert – we will know we have been attacked only when people begin to get sick and seek medical attention. Although some cities have begun to deploy sensors designed to detect bioweapons in the air, these systems are few in number and are unproven technologies in urban settings. In our judgment, it is far more likely that we will realize a bioterrorist attack has occurred when doctors and nurses diagnose the first victims of such an attack. 

Once a bioweapon is released, some time passes before people infected the bioweapon agent become ill. This “incubation period” differs from one bioweapon agent to another. For example, exposure to the anthrax bacteria may cause symptoms as soon as 24 hours later; smallpox symptoms typically don’t begin until 9-14 days after infection.

Protecting yourself and your family in the context of bioterrorism will require that you listen for information and advice from medical and public health authorities.  These are experts who deal with infectious diseases everyday. 

An explosion of any kind is immediately obvious, of course. Similarly, a chemical attack is also immediately apparent. Most chemical weapons act within seconds or minutes – people in the vicinity of the attack become obviously ill very quickly. If you find yourself in the vicinity of such an attack, you should quickly leave the area, moving upwind if possible.

Will sealing windows with duct tape and plastic sheeting help protect me during a bioterrorist attack? 

No. A release of a biological agent is most likely to be “covert” - that is, terrorists will not announce the attack before it happens or afterwards. This means you would not know ahead of time to seal your windows and prevent contaminated air from reaching you. 

Duct tape and plastic sheeting can slow down the movement air from outside to inside, but does not stop such movement.

BE AWARE that using some non-electric space heaters inside such sealed off areas can lead to dangerous build up of carbon monoxide!!

Should I buy a gas mask? 

No. A gas mask would only protect you if you were wearing it at the exact moment a bioterrorist attack occurred.  A biological or chemical terrorist attack is likely to occur without notice. To wear a mask continuously or “just in case” a terrorist attack occurs, is impractical, if not impossible. 

To work effectively, masks must be specially fitted to the wearer, and wearers must be trained in their use.  This is usually done for the military and for workers in industries and laboratories who face routine exposure to chemicals and germs on the job. Gas masks purchased at an Army surplus store or off the Internet carry no guarantees that they will work.  

Should I purchase disposable masks as part of a home emergency disaster kit? 

Again, a bioterrorist attack will likely be covert, so you will not know when to put on the mask. By the time the attack is recognized – days or even weeks after the release of the bioweapons agent – it is too late to don a mask.

Paper masks offer little, if any, protection against chemical weapons.

More generally, there may be disaster situations in which it will be important to avoid breathing in dangerous substances. For example, an explosion may produce fine debris or toxic gases that can hurt your lungs. Wearing a simple mask in such situations may be helpful. Be prepared to improvise – use what you have on hand to create a barrier between the air and your mouth and nose.

There are different opinions as to what sorts of barriers work best and there are few solid facts. Anything that fits snugly over your nose and mouth, including any dense-weave cotton material, can help filter contaminants in an emergency. There are also a variety of face masks readily available in hardware stores that are rated based on how small a particle they can filter in an industrial setting. For the moment, you have to decide what is best for you and your family. 

It is very important that the mask or other material fit your face snugly so that most of the air you breathe comes through the mask, not around it.  Do whatever you can to make the best fit possible for children. Simple cloth facemasks can filter some of the airborne particles or germs you might breathe into your body, but will probably not protect you from chemical gases.  Still, something over your nose and mouth in an emergency is better than nothing.     

If I decide to buy disposable masks, what type should I buy? 

There are many kinds of disposable masks. About N95 masks: these are a type of simple, inexpensive paper mask often mentioned in emergency preparedness literature. The filtering ability of the N95 mask – a measure of how much material can pass through the paper in laboratory tests – is quite high. N95 masks effectively protect against infection in hospital settings in which health care professionals have time to make sure the masks fit properly.

In the setting of civilian response to a bioterrorist attack, it is not clear than an N95 mask would be any more effective than other paper masks or provide more protection than a cotton undershirt wrapped around the nose and mouth. (Manufactured masks may, however be more comfortable and more convenient.)

The reason for this is that paper masks often fail to fit the face snugly, and a lot of air leaks in around the edges of any paper mask instead of getting filtered through the paper. This is why it is important to make sure that any mask you use or create fits tightly around your face.

Should I have my own supply of antibiotics in case there is a bioterrorist attack? 

There are a number of different germs a bioterrorist might use to carry out an attack.  Many antibiotics are effective for a variety of diseases, but there is no antibiotic that is effective against all diseases. Further, no antibiotics are effective against virus germs. Thus, no single pill can protect against all types of biological weapon attacks. Keeping a supply of antibiotics on hand poses other problems because the antibiotics have a limited "shelf life" before they lose their strength.  Antibiotics can also cause serious side effects.  They should only be taken with medical guidance.

What can I do to protect my family and myself during a bioterrorist attack? 

Unfortunately, there is little that individuals can do in advance to protect themselves from a bioterrorist attack. However, there is much that government agencies, health care institutions, and public health departments can and should be doing to improve the capacity to protect the public following a bioterrorist attack. Medical institutions and public health agencies, in particular, have not received adequate attention and resources to cope with disasters like bioterrorism. 

You can express your concern regarding adequate protections against the potential threat of bioterrorism to your elected officials and local leaders. Local health departments have an important responsibility for helping protect your community against outbreaks of infectious disease, whether they occur in nature or because of a malicious terrorist act. They can assist you with additional bioterrorism-related concerns that are pertinent to your own community. In addition, you can contact your congressional representatives to discuss what measures the federal government is taking to provide local authorities with adequate resources to deal with national security threats.

JHU Preparedness Website

Public Affairs Media Contacts for the Johns Hopkins Bloomberg School of Public Health: Tim Parsons or Kenna Brigham @ 410-955-6878 or