See what tests the flu vaccine is undergoing before a mass prevention campaign

The first batch of the Russian-made vaccine Grippol Plus entered the country and passed mandatory quality control. Then - distribution by region and the start of a mass vaccination campaign. Journalists of SB Week visited the unique laboratory of the Republican Center for Hygiene, Epidemiology and Public Health to see how specialists check the safety and compliance of the drug with established standards.

We are in the laboratory of quality control of immunobiological medicines of the Research Institute of Hygiene, Toxicology, Epidemiology, Virology and Microbiology. On the tables rows of test tubes and reagents: the vaccine passes through a sequence of tests, where the slightest deviation from the norm is recorded. This Russian-made drug comes to Belarus annually.

- Although the manufacturer conducts its own quality control, samples of each batch after entering the country are sent to us, says the head of the laboratory Veronika Shimanovich. The first batch this season amounted to 275,000 doses, two more deliveries are expected. For quality control, we select four packages - 20 doses. This number is considered representative and allows you to evaluate the whole series. We check the list of indicators established by the Belarusian legislation. The laboratory of the Institute mainly pays attention to the safety of the drug. One of the mandatory tests is to determine the level of bacterial endotoxins that can cause a fever after the introduction of the vaccine. These substances must be in a strictly regulated range.

Another indicator is specific safety: the absence of a live virus. Despite the fact that the vaccine is inactivated, the laboratory confirms this experimentally. The test is performed on chicken embryos and takes a week. Additionally, the toxicity of the drug is assessed - this stage also lasts about a week. They also check the content of ovalbumin. The virus for the production of influenza vaccine is grown on chicken embryos. During purification, they are removed, but trace amounts in the finished preparation can be preserved. These values are regulated and regulated by the World Health Organization. The laboratory specifies whether the content of ovalbumin does not exceed the established limit.

- It is because of the minimum residual content of drugs are contraindicated in people with allergies to chicken protein, the laboratory said. In general, vaccine production is divided into two types: derived from chicken embryos and cultured cells. The second option is much more expensive and is available in limited series. Influenza vaccines have not been rejected. Additionally, the pH indicator is determined - the physicochemical state of the vaccine. If the value deviates from the norm, this may indicate the beginning of oxidative processes. During quality control, specialists also study the manufacturer’s documents. For example, analysis of the consolidated protocol is considered international practice and is included in WHO recommendations. This document describes all production stages, control methods and test results at each intermediate stage, including the evaluation of antigens.

This is a key feature of the control of immunobiological drugs. The final form does not always contain a complete set of indicators necessary for quality assessment, since a significant part of the parameters are checked at intermediate stages. For example, the presence of influenza protein is determined before packaging.

The batches of the vaccine are stored in the warehouse of the supplier and require strict compliance with the temperature regime - from +2 to +8 degrees. Other temperatures are considered unacceptable: protein preparations are sensitive to both freezing and overheating, leading to destruction. The full cycle of control of influenza vaccine takes 7-8 days. After the laboratory control is completed, we draw up a protocol, which we transfer to Belpharmacy for further distribution of drugs by region. Influenza vaccines have not been rejected, although there are cases of rejection of other immunobiological drugs. The Quality Control Laboratory is the only laboratory in the country where biological medicines are evaluated. The range of such funds is wide: vaccines, serums, immunoglobulins, drugs based on monoclonal antibodies used in oncology, insulins, enzyme preparations, probiotics. All of them are biological, because they are produced using natural biological materials.

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The laboratory also conducts research using laboratory animals. For this purpose, a room is equipped where mice, guinea pigs, rabbits and rats are kept. By the way, on guinea pigs and mice, the abnormal toxicity of the influenza vaccine is estimated. Vaccinated animals are placed separately, the cells are marked with the name of the drug and the dose.

Each type of vaccine has its own characteristics, but inactivated, unlike live ones, are considered more universal and are purchased in large quantities. They are divided into celnovirion, subunit and split, while all options demonstrate sufficient effectiveness.