The cold chain is what?

In medicine, a variety of terms are used. Not everyone understands their significance. It is often possible to hear such a phrase as "compliance with the cold chain". Usually it is used for transportation of medical products. Next, I will discuss this concept in detail.

Definition

What is a cold chain? It is an uninterruptedly functioning system of organizational and practical measures that provides the optimal temperature during storage and transportation of immunobiological-type medical products (including those used for immunization) at each stage of their journey from the manufacturing enterprise to the one to whom the vaccination is indicated.

Purpose

The cold chain is one of the most important components of the organization of immunoprophylactic warnings of infectious diseases.

The need for this system is due to the fact that vaccines currently in use need strict adherence to the temperature regime during storage and transport. Its violation can lead to both partial and complete loss of immunogenic activity by the preparations, which has a direct effect on the effectiveness of enhancing immunity. In this case, the population will no longer trust the vaccinations.

Vaccine Activity and Loss

Each vaccine is a sensitive biological substance. Over time, its activity is lost. Much faster this process occurs if exposure to unfavorable (higher or lower than the recommended range) temperature conditions occurs. If the activity of the vaccine has been lost in unsuitable conditions, it can not be restored even if the temperature regime becomes recommended. Thus, the loss of vaccine activity is irreversible. Therefore, the cold chain is a necessary measure, which is important for maintaining the activity of the drug until its introduction into the human body.

Any vaccine will necessarily lose activity if stored at too high a temperature. But the sensitivity to elevated temperature can be different. The most thermally sensitive are such vaccines:

• Mumps;
• Poliomyelitis;
• Pertussis;
• Measles;
• Against hepatitis B.

Tetanus toxoid is less sensitive to elevated temperature.

Vaccines are also affected by sensitivity to reduced temperature. So, some are able to endure the process of freezing without losing their activity, while others under such conditions are destroyed.

Cold chain system

The system of such a chain includes:

1. Personnel who are specially trained. It ensures the proper operation of all equipment, storage and transportation of drugs.

2. Refrigeration equipment that is designed to store and transport vaccines under optimal temperature conditions.

3. A mechanism that controls compliance with all necessary temperature conditions at each stage of storage and transport of vaccines.

Training

In many Russian cities, interregional special courses are held, on which the main theme is the "Cold Chain". These are activities where specialists are trained, working in the state sanitary and epidemiological services, health care institutions, pharmacies and enterprises where medical immunobiological preparations are manufactured.

Equipment development

The requirements for compliance with the cold chain are strictly regulated by the relevant law. The organization of health in the framework of the special program stimulated the creation and implementation of new models of refrigeration equipment in order to equip the cold chain system in a technical way. One hundred and fifty kinds of similar equipment have already been developed abroad. These are freezers and refrigerators, including specimens working on alternative energy sources, thermal containers with various capacities for single use as well as for repeated use, cold chain temperature indicators and cold cells, refrigerated bags. Most of the devices are successfully used in different parts of the world.

Implementing a special program for vaccine prevention, the country first began to develop and produce on industrial scales various thermal containers. Under the same program, the Ministry of Health provided products to enterprises that produce basic vaccines. Automatic refrigerators were bought.

Thermocontainer and coolant

This equipment is a box that is made of a special thermo-insulating material. Has a tightly closed lid of the same material. The dimensions of the thermal containers can be different. Their inner surface must be covered with a layer that allows for sanitization. Required temperature mode inside the container is provided by the cold cells. These are sealed containers that are filled with water or a special solution. Before being placed in a container, it is subjected to freezing during the day. If the cooler is defrosted, it must be replaced by another in a special warehouse.

Thermal indicator for cold chain monitoring

This device is designed to monitor compliance with the standards of storage and transportation of immunobiological drugs, medicines and blood. It detects a violation of the temperature regime in the circuit and displays it. Thermal indicator - a very important device designed to ensure that the vaccine does not lose its activity. Falsification of indications from quality devices is completely excluded. New models are able to store all previous violations in their electronic memory.

Results

The head of each health institution should develop and approve a plan of measures to ensure the cold chain. If, on the whole, we assess the state of the organization of this event in Russia, we should note the following: even in spite of noticeable progress in this direction, much more needs to be done at each level of health management. It is also necessary to work in the field of practical activities related to training people, creating modern equipment, quality control tools, and organizing production on an industrial scale and providing all necessary production facilities, pharmacy and health facilities, and sanitary and epidemiological services.