RU2500353C2 - Method of predicting development of diseases of respiratory organs in people subjected to impact of biological factor - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to labour medicine, and can be applied for predicting risk of development of diseases of respiratory organs in people subjected to impact of microbiological factor. For this purpose, sampling of air from working zone of workers, subjected to impact of microbiological factor and sampling of air from working zone of workers of the same enterprise, who are not subjected to impact of said factor, are performed. After that, said samples are inoculated on nutritional medium. Total number of microorganisms in air samples is determined by calculation of grown colonies (total microbiological number). After that, index of microbiological risk is calculated as ratio of total microbial number in air of working zone of workers, subjected to impact of microbiological factor, to total microbial number in air of working zone of workers of the same enterprise, who are not subjected to impact of said factor. If value of said index is lower than 1.9, risk of development of diseases of respiratory organs is estimated as low. If index value is from 2.0 to 4.9, risk is estimated as medium. If values are from 5.0 to 6.9, risk is estimated as high. If index is higher than 6.9, risk is considered to be very high.

EFFECT: method makes it possible to perform reliable prediction of development of pathology of respiratory organs in people subjected to impact of opportunistic and pathogenic microorganisms in case of absence of other risk factors, at the stage of premorbid changes.

2 cl, 4 ex, 2 tbl

Description

The invention relates to medicine, in particular to occupational medicine, and can be used to predict the development of respiratory diseases in individuals exposed to biological factors.

Respiratory diseases are one of the main causes of disability and mortality. Respiratory diseases occupy one of the leading places in the structure of occupational diseases. So, according to data for 2009, respiratory diseases accounted for about 30% of the share of all occupational diseases [Occupational diseases and their distribution by classes of working conditions in the Russian Federation in 2009: an information collection of statistical materials. - M., 2010. - 9-14 p.].

As you know, various factors play a role in the occurrence of respiratory diseases. So, in the conditions of agricultural complexes and in healthcare enterprises, workers are at high risk of infection with various pathogenic biological agents (bacteria and fungi). The factors of the transfer of microorganisms in agricultural enterprises are most often feed, dairy products, incubation waste, soil, etc., at the healthcare enterprises, the transient microflora acquired by medical personnel during work as a result of contact with infected (colonized) patients or contaminated is of the greatest epidemic importance. environmental objects.

In addition, there are other unfavorable production factors that contribute to a decrease in workers' natural resistance, the propagation of opportunistic microorganisms and the manifestation of their pathogenic properties by them. These factors can be one of the most important in the development of respiratory diseases in workers of other industries.

The influence of a biological factor is one of the leading mechanisms of the development of respiratory diseases, i.e. under the influence of microorganisms in the course of labor, workers may be exposed to a certain microbiological risk of developing respiratory diseases.

The prototype of the invention is a method for assessing occupational risk in workers exposed to harmful production factors, including calculating the relative risk (RR, units) and the etiological fraction (EF,%) no Miettinen (1978) according to the formula: RR = P1 / P2, units. ; where: P1 - the prevalence of pathology in workers exposed to one or another harmful production factor; P2 - the prevalence of pathology in people who do not work in contact with these production factors; EF = (RR-1) / RR,%, and the relationship of the identified violations with work is calculated according to the table [“Methodology for identifying occupational diseases and diseases associated with working conditions” N.F. Izmerov, E.I. Denisov, Methodological recommendations. Moscow. - 2010]. The disadvantage of this method is that it takes into account occupational risks for workers according to the results of retrospective epidemiological studies.

The objective of the invention is to develop a method that allows with high reliability to predict the development of respiratory diseases in workers exposed to pathogenic and conditionally pathogenic microorganisms in the absence of other risk factors, at the stage of premorbid changes.

EFFECT: obtaining criteria for predicting the development of respiratory diseases in workers exposed to a microbiological factor at the stage of premorbid changes.

The general hygienic assessment of working conditions at agricultural enterprises and healthcare institutions, in accordance with generally accepted standards in the field of occupational medicine, occupational hygiene, is carried out in accordance with Guide R 2.2.2006-05 “Guidelines for the hygienic assessment of working environment and labor process factors. Criteria and classification of working conditions ”[Guidelines for the hygienic assessment of factors of the working environment and the labor process. Criteria and classification of working conditions: Guide R 2.2.2006-05 / Ed. N.F. Izmerova // Bulletin of normative and methodological documents of the Sanitary Inspection. - 2005. - No. 3 (21). - S.3-144]. The manual states that the classes of working conditions by biological factor are evaluated depending on the content in the air of the working zone of microorganisms, pathogens of infectious diseases, i.e. the microbiological factor according to the manual is regarded as a biological factor.

The proposed method for predicting respiratory diseases in individuals exposed to a microbiological factor is as follows: determine the total number of microorganisms (total microbial number) located in 1 m ^{3 of} air in the working area of workers exposed to a biological factor (study group of workers) and working zones of employees of the same enterprise not exposed to biological factors (control group of employees):

- Set the cup with a dense nutrient medium, for example, meat peptone agar, in the holder of the sampler - the impactor of microbiological air "Flora-100".

- Press the button marked with the required volume of extracted air of 250 l, while the red indicator light above the button lights up.

- An air sample is taken by the aspiration method by pressing the [NETWORK] button located on the left side of the sampler. After taking a predetermined volume of air, the indicator lamp goes out.

- A sample cup on meat peptone agar is placed in a thermostat and incubated at 37 ° C for 24-48 hours.

- Count the number of grown colonies on the plate, and multiply this number by 4. Get the value of the total microbial number (TBC). The result is expressed in colony forming units per 1 m ³ (CFU / m ³ ).

To predict the development of respiratory diseases, an index of microbiological risk (MR) is introduced, which is calculated as the ratio of the total microbial number in the air of the working area of workers exposed to the biological factor to the total microbial number in the air of the working area of employees of the same enterprise who are not exposed to the biological factor .

$$MR=\frac{\mathrm{ABOUT}MH\mathrm{one}}{\mathrm{ABOUT}MH0}$$

MR - microbiological risk of respiratory diseases

TMP 1 - the total microbial number in the air of the working area of workers exposed to the microbiological factor (study group of workers),

TBC 0 is the total microbial number in the air of the working zone of workers of the same enterprise who are not exposed to the microbiological factor (control group of workers).

Value

MR up to 1.9 is a small microbiological risk of developing respiratory diseases in workers of the study group. Persons of this group are subject to regular medical examinations as working in harmful and hazardous working conditions.

MR 2.0-4.9 - the average microbiological risk of developing respiratory diseases in workers of the study group. Persons of this group are subject to dynamic observation. It is necessary to determine the composition of the microflora of the upper respiratory tract.

MR 5.0-6.9 - a high microbiological risk of developing respiratory diseases in workers of the study group. It is necessary to determine the composition of the microflora of the upper respiratory tract with the determination of sensitivity to antimicrobial drugs in order to prescribe outpatient treatment.

MR more than 6.9 - a very high microbiological risk of developing respiratory diseases in workers of the study group. This group of workers needs an in-depth examination in a hospital with the aim of early diagnosis of respiratory pathology.

The definition of prognostic markers is of great practical importance, since the identification of initial reversible forms, occupational diseases is one of the priority areas of preventive diseases.

According to the results of sanitary and hygienic studies at the enterprises of the agro-industrial complex and healthcare institutions, we found that in these enterprises, in addition to microbiological pollution, there is a complex of other harmful production factors of the working environment and labor process (air pollution of industrial premises with chemicals, plant dust and animal origin, exposure to noise, physical activity, etc.). In this regard, in this work, in order to predict the development of respiratory diseases, the indicators of microbiological risk (MR) in the air of the working zone are selected only for those groups of workers whose working conditions are similar to other harmful production factors of the working environment and the labor process ( air pollution of industrial premises with chemicals, dust of plant and animal origin, exposure to noise, physical stress, etc.) corresponded to the permissible class of working conditions (class 2 asno Guide P 2.2.2006-05 "Guidelines for the hygienic assessment of factors of working environment and labor process. The criteria for the classification and working conditions").

We examined workers in the agro-industrial complex and employees of healthcare institutions (n = 2579), all the workers examined were female, aged 27–55 years. The working conditions of these workers in terms of other harmful production factors of the working environment and the labor process (air pollution of industrial premises with chemicals, plant and animal dust, exposure to noise, physical stress, etc.) corresponded to the permissible class of working conditions (class 2 according to Guideline P 2.2 .2006-05 "Guidelines for the hygienic assessment of the factors of the working environment and the labor process. Criteria and classification of working conditions"). The working conditions of workers in terms of the microbiological (biological) factor corresponded to the harmful class (class 3). Other factors that are considered as a biological factor corresponded to the permissible class of working conditions (class 2).

In accordance with the value of TBC in the premises, all employees were divided into five groups: I, II, III, IV and the control group.

The control group consisted of agricultural workers and employees of healthcare institutions (n = 619) engaged in engineering and technical work (engineers) (accountants, engineers), the working conditions of engineers on all factors corresponded to the permissible class of working conditions.

According to the results of a periodic medical examination, 52 employees of the control group revealed respiratory diseases, which amounted to 8.4% (table 2).

It was found that with an increase in TMS in the premises of enterprises, among workers in the corresponding premises, the prevalence of respiratory diseases (r> 0.8) increases.

So, in the first group of workers employed in premises where the airborne OMC of the working area was significantly higher (p <0.05) than in the control group (table 2), respiratory diseases were diagnosed significantly more often than in workers in the control group ( p <0.05).

In the II group of workers employed in premises where the airborne TMS of the working area was significantly higher than in the control group, and I group (p <0.05), respiratory diseases were detected significantly more often than in group I (p <0 , 05) than in the control group (p <0.001).

In the III group of workers employed in premises where the airborne OMC of the working area was significantly higher than in the control group, I and II groups (p <0.05), respiratory diseases were detected significantly more often than in workers of the II group (p <0.05) than in group I (p <0.05) and than in the control group (p <0.001).

In the IV group of workers employed in premises where the airborne TMS of the working zone was significantly higher than in the control group, I, II, and III groups (p <0.05), respiratory diseases were significantly more frequent than in the III group of workers ( p <0.05) than in the II group of workers (p <0.05), than in I (p <0.05) and than in the control group (p <0.001).

The formula indicated in the prototype was applicable to the data obtained by us (indicators of the prevalence of respiratory diseases) and confirmed the results. Based on the results, according to the methodological document indicated in the prototype, we formed four groups of workers who were diagnosed with respiratory diseases with varying degrees of causal relationship with health problems at work:

Group 1 (n = 616) - a group of workers with a small degree of causal relationship of health problems with work.

Group 2 (n = 641) - a group of workers with an average degree of causal relationship of health problems with work.

Group 3 (n = 405) - a group of workers with a high degree of causal relationship of health problems with work.

Group 4 (n = 298) - a group of workers with a very high degree of causal relationship of health problems with work

As a result of calculating the MR of the development of respiratory diseases for workers in these groups, it was found that the MR for 1 group of individuals was in the range up to 1.9; MR for 2 groups of individuals ranged from 2.0-4.9; MR for 3 groups of individuals was in the range of 5.0-6.8 cu; for the 4th group of individuals - MR was 6.9 or more.

The proposed method is illustrated by the following clinical material:

Example 1

Workers of the Maternity herd workshop of the N-th poultry farm are exposed to harmful production factors in agriculture (n = 20). TBC in the air of the working area of the Maternity herd workshop is 7000 CFU / m ³ .

The control group is employees of the engineering and technical service of the N-th poultry farm, OMC in the air of the working area of production facilities 820 CFU / m ³ .

Conclusion: MR = 8.5, which corresponds to a very high microbiological risk. This group of workers needs an in-depth examination in a hospital with the aim of early diagnosis of respiratory pathology.

Example 2

Workers in the profession of "nurse" department №10 infectious diseases hospital in Ufa. TBC in the air of the working area of the treatment room, 2500 CFU / m ³ .

A control group of employees of the engineering and technical services of the infectious diseases hospital in Ufa, TBC in the air of the working area of industrial premises 500 CFU / m ³ . Conclusion: MR = 5.0, which corresponds to a high microbiological risk, a high probability of developing respiratory diseases in workers of the study group. It is necessary to determine the composition of the microflora of the upper respiratory tract with the determination of sensitivity to antimicrobial drugs in order to prescribe outpatient treatment.

Example 3

Workers of the Utilization workshop of the N-th poultry farm are exposed to harmful production factors in agriculture (n = 20). TBC in the air of the working area of the Utilization shop 2200 CFU / m ³ .

The control group is employees of the engineering and technical service of the N-th poultry farm, OMC in the air of the working area of production facilities 820 CFU / m ³ .

Conclusion: MR = 2.7, which corresponds to the average microbiological risk, the average likelihood of developing respiratory diseases in the workers of the study group. Persons of this group are subject to dynamic observation. It is necessary to determine the composition of the microflora of the upper respiratory tract.

Example 4

Workers in the profession of "doctor" of department No. 10 of the infectious diseases hospital in Ufa. TBC in the air of the working area of the resident, 900 CFU / m ³ .

A control group of employees of the engineering and technical services of the infectious diseases hospital in Ufa, TBC in the air of the working area of industrial premises 500 CFU / m ³ . Conclusion: MR = 1.8, which corresponds to a small microbiological risk, there is a likelihood of developing respiratory diseases in the workers of the study group. Persons of this group are subject to regular medical examinations as working in harmful and hazardous working conditions.

table 2 The prevalence of respiratory diseases in workers under the influence of a biological factor (per 100 employees) Indicators Group I Group II Group III Group IV Control group The number of employees in the group (n) 616 641 405 298 619 Mat. waiting (M) 12.1 16.1 21,2 28.5 8.4 Standard error of the mean (m) 1.3 1.45 2.0 2.6 1,2 95% confidence interval Up to 12.5 12.6-16.8 16.9-26.8 From 26,9 Up to 8.4

Claims (2)

1. A method for assessing the risk of developing respiratory diseases in individuals exposed to a microbiological factor, including calculating the relative risk, characterized in that a sample of air from the working area of workers exposed to microorganisms and a sample of air from the working area of workers of the same area is sampled on the culture medium enterprises that are not exposed to this effect determine the total number of microorganisms in air samples by counting the grown colonies, the total microbial number by expressing In CFU per 1 m ^{3 of} air, the indicator of microbiological risk is determined as the relative risk, which is calculated as the ratio of the total microbial number in the air of the working area of workers exposed to the biological factor to the total microbial number in the air of the working area of workers of the same enterprise, not exposed to a biological factor and with a value of up to 1.9, the microbiological risk of developing respiratory diseases in workers exposed to a biological factor ora, is estimated to be small, 2,0-4,9 - medium microbiological risk of respiratory diseases; 5.0-6.9 - high microbiological risk; more than 6.9 - a very high microbiological risk. 2. The method according to claim 1, characterized in that meat-peptone agar is used as a nutrient medium.