In medicine, a variety of terms are used. Not everyone understands their meanings. Often you can hear such a phrase as "compliance with the cold chain." It is usually used in the transport of medicines. Next will be described in detail about this concept.
Definition
What is a cold chain? This is a continuously functioning system of organizational and practical measures that ensures the optimal temperature during storage and transportation of immunobiological-type medications (including those used for immunoprophylaxis) at each stage of their journey from the manufacturing enterprise to the one to whom vaccination is indicated.
Destination
The cold chain is one of the most important components included in the organization of immunoprophylactic warnings of diseases of an infectious nature.
The need for this system is due to the fact that the vaccines currently in use require strict adherence to the temperature regime during storage and transportation. Its violation can lead to both partial and complete loss of immunogenic activity by the drugs, which has a direct effect on the effectiveness of increasing immunity. At the same time, the population will no longer trust vaccines.
Vaccine activity and its loss
Each vaccine is a sensitive biological substance. Over time, its activity is lost. Much faster this process occurs if the exposure is adverse (higher or lower than the recommended range) temperature conditions. If the activity of the vaccine was lost under inappropriate conditions, it cannot be restored, even if the temperature regime becomes recommended. Thus, the loss of activity of the vaccine is irreversible. Therefore, the cold chain is a necessary measure, which is important for maintaining the activity of the drug until it is introduced into the human body.
Any vaccine will necessarily lose activity if stored at excessively high temperatures. But sensitivity to elevated temperatures can be different. The most heat-sensitive are the following vaccines:
- mumps;
- polio;
- whooping cough;
- measles;
- against hepatitis B.
Tetanus toxoid is less sensitive to fever.
Vaccines also vary in sensitivity to low temperature. So, some are able to tolerate the freezing process without losing their activity, while others are destroyed under such conditions.
Cold chain system
The system of such a circuit includes:
1. Personnel who are specially trained. It ensures the proper operation of all equipment, storage and transportation of drugs.
2. Refrigeration equipment, which is designed to store and transport vaccines in optimal temperature conditions.
3. The mechanism that controls compliance with all necessary temperature conditions at each stage of storage and transportation of vaccines.
Training
In many Russian cities, interregional special courses are held where the main topic is “The Cold Chain”. These are events where they train specialists working in the state sanitary and epidemiological services, healthcare institutions, pharmacies and in enterprises that produce medical immunobiological preparations.
Equipment development
The requirements for compliance with the cold chain are strictly regulated by the relevant law. The health organization, as part of a special program, stimulated the creation and implementation of new models of refrigeration equipment in order to logically equip the cold chain system. Over one hundred and fifty types of such equipment have already been developed abroad. These are freezers and refrigerators, including copies working on alternative energy sources, thermal containers with different capacities for both single and multiple use, cold chain temperature indicators and cold elements, cooler bags. Most of the devices are successfully used in different parts of the world.
Implementing a special vaccine prevention program, the country first began to develop and manufacture various thermal containers on an industrial scale. Under the same program, the Ministry of Health provided products to enterprises that produce basic vaccines. Automatic refrigerators were purchased.
Thermal container and refrigerant
This equipment is a box, which is made of special thermally insulating material. Has a tight-fitting lid of the same material. The sizes of thermal containers can be various. Their inner surface is necessarily covered with a layer that allows sanitization. The necessary temperature regime inside the container is provided by cold elements. These are hermetically sealed containers that are filled with water or a special solution. Before being placed in a container, it is frozen for a day. If the refrigerant defrosts, it must be replaced by another in a special warehouse.
Temperature indicator for cold chain monitoring
This device is designed to monitor compliance with the storage and transport of immunobiological preparations, drugs and blood. It detects a violation of the temperature regime in the circuit and displays it. A thermal indicator is a very important device designed to ensure that the vaccine does not lose its activity. Falsification of readings from high-quality devices is completely excluded. New models are able to store all previous violations in their electronic memory.
Summary
The head of each medical institution must develop and approve an action plan to ensure the cold chain. If we generally assess the status of the organization of this event in Russia, the following should be noted: even despite significant progress in this direction, much more needs to be done at each level of healthcare management. It is also necessary to work in the field of practical activities relating to the training of people, the creation of modern equipment, means of quality control, as well as the organization of production on an industrial scale and providing all necessary production enterprises, pharmacy and health care facilities, and sanitary and epidemiological services.