nificantly. Pearson provided an overview of four containment levels1 spelled out in these standards.

Pearson explained that the key laboratory capacity issue is that many procedures for higher levels of biosafety are difficult for resource-constrained countries to establish or maintain. Specifically, he explained, biosafety level 2 (BSL-2) laboratories are widely used and available, but, as far as he is aware, few if any laboratories meet all the requirements for BSL-3 in resource-constrained countries. If true, this means that many countries lack the capacity to isolate viruses such as avian influenza. The few BSL-3 laboratories that do exist in underresourced regions—Morocco, South Africa, and Thailand each have a BSL-3 laboratory—may provide support to other countries as well. In general, the high cost of some of the equipment, such as animal inoculation cages, is a principal impediment to setting up a laboratory that meets higher biosafety level requirements.

Pearson also noted that few postmortem facilities in resource-challenged countries are meeting even BSL-1 standards, so that personnel may be exposed to significant risks. The alternative to using facilities that lack sufficient protection is for personnel to conduct testing in the field, wear HAZMAT suits, and bury the animal. This approach, however, may not provide adequate protection. The skill and training of staff are critical, he added. Upgrading training (e.g., training that covers clinical signs, diagnostic tests, optimal response, and disease reporting and control) may be a higher priority, in many cases, than establishing laboratories that meet higher levels. In Pearson’s view, resource-constrained countries in general have conscientious laboratory workers who have received excellent training and have much of the equipment and supplies they need. On the other hand many resources are in short supply, such as facilities with capacity above BSL-1, specialized equipment (e.g., biosafety cabinets), and electric generators. Field forces are small, many personnel need more sophisticated training, and surveillance systems are not providing sufficient samples from the field. He summarized the situation by observing that BSL-2 laboratories are widely used and available in many countries. Although access may not


These recommended containment or biosafety levels (BSL) describe safe methods for managing infectious materials in the laboratory environment where they are being handled or maintained. There are four BSLs, with BSL-1 representing a basic level of containment relying on standard microbiological practices and BSL-4 representing the most advanced containment when working with dangerous and exotic agents that pose a high individual risk of life-threatening disease (which may be transmitted via the aerosol route and for which no vaccine or therapy is available). The increasing numbers correspond to the increasing levels of protection for personnel and the environment. The purpose is to reduce or eliminate exposure of laboratory workers, other persons, and the outside environment to potentially hazardous agents. Each combination is specifically appropriate for the operations performed, the documented or suspected routes of transmission of the infectious agents, and the laboratory function or activity (PHS/CDC/NIH, 1999, 2007).

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement