Viral hepatitis B and C as occupational diseases

Introduction

The relevance of the problem of blood-borne viral hepatitis B and C at the present stage is determined by their global presence, the breadth of routes and factors of transmission, the mild clinical course of chronic hepatitis with the gradual development of adverse outcomes in cirrhosis and liver cancer, limited access to etiotropic therapy, and low public awareness of the disease. The need to address the significant problems of viral hepatitis is reflected in the introduction of the “National Plan for the Elimination of Viral Hepatitis by 2030” in the execution of a Presidential Decree “On National Development Goals for the Russian Federation until 2030”, No. 474 dated July 21, 2020.

A significant risk group for infection includes medical workers (MWs). Among them, viral hepatitis is detected 7–10 times more frequently compared with the general population [1–4]. Viral hepatitis in healthcare workers in the context of healthcare-associated infections has significant epidemiological relevance, and in the stages of cirrhosis and liver cancer represents a clinical and socioeconomic problem.

By 2021, viral hepatitis accounted for 16.7% in the structure of occupational morbidity of healthcare workers (n=174) in the Republic of Tatarstan, being second only to tuberculosis (51.1%), and slightly exceeded the number of cases of new coronavirus infection (16.1%) [4].

The study aimed to evaluate the clinical and epidemiological features and medical and social aspects of viral hepatitis B and C in MWs.

Study tasks:

1. To present clinical and epidemiological characteristics of MW patients with diagnoses of hepatitis B virus (HBV) and hepatitis C virus (HCV).
2. To evaluate the awareness of MWs and undergraduate medical students about the risks and possibilities of preventing infection with HBV and HCV at the present stage.
3. To update the problem of HBV as an occupational disease.

Materials and Methods

The authors analyzed outpatient and inpatient records of MWs with established diagnoses of chronic viral hepatitis B, C, B+C, B+D of various degrees of activity (n=45) who were registered in the Republican Center of Professional Pathology (RCPP) and/or consultative and diagnostic department of the Republican Infectious Clinical Hospital named after Prof. A.F. Agafonov in Kazan. The patients with an established relation between HBV and their occupation (n=29) underwent analysis of epidemiological examination cards on the infectious disease and evaluation of the sanitary and hygienic characteristics of working conditions.

To assess the awareness about the risks and possibilities of preventing blood-borne hepatitis infection in medical specialists, a sociological survey was carried out using Googlе Forms with the participation of MWs and undergraduate medical students of Kazan city (n=254). The survey included closed-type questions (about the knowledge of preventive measures in case of an accident, determination of protective antibody titer after hepatitis B vaccination, including before employment in a medical institution and/or before internship), and semi-open-ended questions to clarify circumstances of accidents [5]. Methods of descriptive statistics with the definition of fractions in percent were used to present the obtained data.

Results

All MWs with diagnosed acute or chronic viral hepatitis (n=45) were divided into three groups based on the history of occupational infection. In the first group of MWs (n=29), RCPP confirmed the association between the disease and their profession. The second group comprised MWs who associated the infection with their professional activity but did not contact RCPP for various reasons (n=8). The third group included MWs who denied a connection between viral hepatitis disease with their profession (n=8). Most MWs were older than 50 years (64%), and there were more women in the study (71%).

Among MWs with HBV, 44.4% were doctors of surgical specialties: obstetricians-gynecologists, intensive care specialists, otolaryngologists, surgeons, and dentists; 44.4% were nursing staff working in intensive care units (ICUs), ambulance paramedics, and clinical diagnostic laboratory nurses (11.2%). The vast majority (82.6%) of healthcare workers had over 10 years of work experience at the time of getting infected. Working conditions (because of contact with pathogens of infectious and parasitic diseases) were assessed as hazardous three classes of grade 3, according to sanitary and hygienic characteristics of the working conditions. All MWs had a history of an accident – needle pricks, cuts, and blood splashing.

Hepatitis C prevailed in the etiological structure of MWs (55.5% (n=25)); in the group of MWs infected outside professional activities, the share of patients with HCV was 62.5%, which confirms a high spread of the infection and the breadth of transmission routes of the pathogen in the general population. Twenty MWs were infected with HBV, and three of them had mixed hepatitis (2 – HB+C, 1 – HB+D). Serologic markers of viral hepatitis were detected in 86.6% of MWs during routine pre-occupation or periodic physical examinations, and 13.4% of MWs had acute manifest hepatitis jaundice. The majority of observed MWs (44.8%, 75%, and 62.5% in the first, second, and third groups, respectively) had the disease detected at the stage of chronic hepatitis. In all studied groups, there was a significant share of outcomes in the stage of liver cirrhosis – 27.6%, 25%, and 37.5% of cases, respectively. Four patients (8.8%) had lethal outcomes as a result of decompensation of liver cirrhosis.

Antiviral therapy (AVT) was given only to 48.8% of MWs with chronic viral hepatitis, 8 of them (36.3%) started therapy at the stage of liver cirrhosis. Among HCV-infected patients, only 60% (n=15) received AVT. Viral elimination was achieved in all HCV-infected MWs who received AVT, including 2 patients with cirrhosis who did not respond to combined interferon therapy and were subsequently treated with direct antiviral agents. Among nurses with chronic HBV, only 5 (25%) patients received therapy; in one nurse, repeated courses of long-term combined AVT resulted in HBsAg seroconversion, which persists to the present time. Four patients received long-term (over 3 years) AVT with nucleoside analogs (entecavir, tenofovir), which resulted in persistent aviremia without HBsAg seroconversion. Most patients (60%) required additional examinations (including at their own expense) to decide on the prescription of AVT. Two patients with chronic HCV who did not receive AVT (10%) had a lethal outcome resulting from decompensated cirrhosis.

In the group of MWs with chronic HCV, hepatitis B vaccination history was assessed: 20% were not vaccinated, 36% had documented indications for hepatitis B vaccination, and none of them had their protective anti-HBs levels determined. In 44% of MWs with chronic HCV, there was no medical record evidence of hepatitis B vaccination administration/rejection or contraindication, which is an important step in the collection of an anamnesis from both occupational risk and clinical relevance perspectives.

To assess the awareness of the risks and possibilities of prevention of blood-borne hepatitis infection among MWs and undergraduate medical students in Kazan city, an online survey using Google Forms was conducted. The survey involved 100 doctors, 137 students, and 17 mid-level medical staff (nurses) with a total of 254 people. Of these, 63% were employed, 15% had previously worked in medical institutions; 118 people (60%) had work related to invasive medical manipulations, of which 49 people (41.5%) had accidents (19 people (39%) did not record the accident in the logbook). Among the responses about the reasons for not recording the accident were the following options: “did not know”, “did not want to”, “was not allowed by the supervisor”, “was told it was not necessary”, “was told there was no risk”. A total of 91% of respondents were vaccinated against hepatitis B, but only 17% of them knew their anti-HBs levels; only 15% of respondents had determined a protective antibody titer prior to employment at a medical institution and/or prior to their internship. Seven percent of respondents were not vaccinated against hepatitis B; most of them were international exchange students. Most respondents (89%) showed an awareness of preventive measures in case of accidents, but 61% of participants felt the need to learn about the algorithm of actions in case of accidents.

Discussion

Hepatitis B, C, and D viruses are highly pathogenic infectious agents; they are classified as microorganism pathogenicity group II (Appendix 1 to SanPiN 3.3686-21 “Sanitary and Epidemiological Requirements for the Prevention of Infectious Diseases”). It is known that medical personnel whose work is associated with invasive medical interventions are at the highest risk of blood-borne infections [1–4]. All MWs had the anamnesis of accidents, which occurred more often when the work experience exceeded 10 years, which can be explained by some decrease in alertness, certain disregard of safety measures associated with a vast experience, and age peculiarities. Besides, it can be assumed that the load and intensity of work in conditions of shortage of experienced medical personnel increased.

In all the studied groups, there was a significant share of outcomes in liver cirrhosis and four patients had lethal outcomes because of the decompensation of liver cirrhosis. The obtained data correlate with the known peculiarities of chronic viral hepatitis: the mild clinical course of the disease, accidental (and sometimes late) diagnosis in the absence of mass screening of the population for HBV markers, limited access to timely and effective AVT, and unfavorable clinical outcomes [6][7]. At the same time, MWs have a significant advantage, which is the early detection of infection during periodic medical examinations.

A clinical case is presented as a demonstration.

Clinical case

Patient N., born in 1963, was occupied as a general practitioner. In 1993, she was hospitalized with a jaundiced form of acute hepatitis B, which developed during the incubation period after an accident (needle prick). In 1993, she worked as an ICU nurse in a multidisciplinary hospital. Her length of service at the time of the accident was 11 years. She was not vaccinated against hepatitis B, as the vaccination began in the Russian Federation only in 1994–1995.

In 1994, the connection of the disease with her occupation was established. She was regularly examined in the RCPP and observed by an infectious disease specialist in the office of infectious diseases of the city polyclinic.

In 2002, she was diagnosed with cytolysis exceeding the upper limit of the norm by 2–3 times and cholestasis with the bilirubin level increasing to 2–3 times of the upper normal level. She was referred to RCPP of A.F. Agafonov Republican Clinical Hospital in Kazan with these clinical findings to decide on AVT. The patient refused the prescribed antiviral interferon therapy, explaining her refusal by adverse events of interferons. For a long time, the patient received pathogenetic therapy with ursodeoxycholic acid, essential phospholipids, and recreation-resort treatment. She continued outpatient observation in the outpatient clinic at her place of residence. In 2021 (18 years after infection), because of repeated episodes of gastrointestinal bleeding, she was hospitalized with the diagnosis of “Chronic hepatitis B, no delta agent, with outcome in liver cirrhosis, class B according to Child-Pugh (8 score) with cytolysis syndrome, cholestasis, portal hypertension (2nd-degree oesophageal varices, ascites), and hemorrhagic syndrome”. Group 3 disability was established and a 40% loss of working ability was determined, contraindications to work in contact with infected material and hepatotoxic substances were revealed.

This case illustrates the realization of infection risks in MWs with a long work experience while performing routine professional duties. Many MWs form their own opinion about the problem of HBV. Sometimes, they do not fully assess the outcomes of the natural course of the infection process, attach great importance to pathogenetic therapy, and have outdated ideas about etiotropic therapy. Adverse outcomes reduce the quality and life expectancy of MWs and lead to significant economic costs.

A principal solution to the problem of chronic viral hepatitis is etiotropic therapy [6–8]. Antiviral treatment is recommended for all patients with HCV to eradicate the virus. At the present stage, effective and safe AVT regimens with direct-acting antiviral drugs are registered in the Russian Federation. In 2021, the implementation of the program aimed at hepatitis C elimination in the general population and in priority risk groups, including MWs, started [8]. AVT is indicated to patients with chronic HCV and persistent elevation of aminotransferases, high viral load, and signs of liver fibrosis/cirrhosis [6]. Early prescription of AVT to infected MW patients is necessary to reduce the risk of healthcare-associated infection transmission and to improve prognosis and quality of life. Unfortunately, according to the available data, among all MWs with chronic viral hepatitis, AVT was administered in only half of the patients (48.8%). One-third of the patients started it late, at cirrhotic stages of the disease, and it did not significantly affect the prognosis of the adverse outcome.

An important preventive measure against hepatitis B, both in the population and professional medical environment, is vaccination regulated by the Federal Law of September 17, 1998 No. 157-FZ (ed. of July 2, 2021) “About immunoprophylaxis of infectious diseases” and Decree of the Russian Ministry of Health of December 06, 2021 No. 1122 n “About approval of the national calendar of preventive vaccinations, the calendar of preventive vaccinations based on epidemic indications, and the procedure of preventive vaccination”.

According to Danilova, before the implementation of mass immunization against hepatitis B in 1994, the morbidity rate of MWs was 35 per 100 thousand people, and in 2000, this rate decreased to 7.04 per 100 thousand people. In the structure of professional diseases, the HBV rate was 77%, and closer to 2008 – 15% [9].

The presence of HCV can be considered a clinical indication for hepatitis B vaccination, since the development of mixed hepatitis is significantly more frequent and faster leads to adverse outcomes and therapeutic failures [10][11][12]. After a completed course of vaccination, it is necessary to determine the titer of protective anti-HBs, since the intensity of postvaccination immunity decreases with increasing time after vaccination [13]. The obtained data on low hepatitis B vaccination coverage in the group of healthcare workers with chronic HCV (80%) and the lack of determination of protective anti-HBs titers in vaccinated patients with chronic HCV reflect healthcare workers’ lack of understanding of the viral hepatitis problem both from the position of professional risk and from the position of clinical relevance.

The presented data of analysis of medical documentation, clinical case, and the results of the survey demonstrate current problems of viral hepatitis as an occupational disease. They include the existing possibility of infection during accidents related to the performance of routine professional duties, especially under conditions of physical and psychological stress; the absence of routine screening for anti-HBs titer and hepatitis B vaccination/revaccination; denial in registration of the accident in the logbook; and denial in the preparation of the documents and late reference to RCPP. Health workers have a fear of losing their job or position, or experience a negative attitude from the administration of healthcare facilities in case of registration of an occupational disease. Lack of information about medical and social support in case of occupational disease, underestimation of the clinical relevance of the disease, adverse outcomes of virus hepatitis, low awareness, and limited access to etiotropic therapy affect the duration and quality of life of MWs and increase the risk of spread of blood-born viral hepatitis as healthcare-associated infections.

Conclusions

1. In the structure of professional morbidity of MWs in the Republic of Tatarstan, viral hepatitis accounts for 16.7%. The rate of women older than 50 years, with more than 10 years of work experience at the time of infection, prevails. Frequent unfavorable outcomes in liver cirrhosis were registered in 28.8% (n=13), a lethal outcome was observed in 4 patients, and effective AVT was received by only 60% of MWs with chronic HCV, and 25% – with chronic HBV.
2. Currently, there remains a risk of HCV infection in MWs of any level of education and status that occurred in accidents, including medical students during internships and volunteer assistance.
3. Among MWs with chronic HCV, 20% were not vaccinated against hepatitis B; and none of those vaccinated (36%) had their anti-HBs titer tested, despite the fact that HBV vaccination/revaccination is regulated by legal documents and is indicated for all healthcare workers, including those with chronic HCV, and requires monitoring of immunity strength.

Conclusion

1. It is necessary to include screening of all MWs for anti-HBs titers as part of pre-occupational and periodic physical examinations, followed by hepatitis B vaccination/revaccination in the absence of a protective antibody titer.
2. Establishment of a link between HBV and occupation in MWs should be considered an urgent indication for prescribing early AVT at the expense of the Social Insurance Fund, which requires coordination of activities of an occupational pathologist, an infectious disease specialist of an expert-level medical institution, and specialists of the social security medical assessment board.
3. It is necessary to update regularly the level of knowledge of MWs about the measures and algorithms of specific and non-specific prevention of occupational HBV infection, and examination of HBV in connection with the profession within the framework of university and continuing medical education.

Authors’ contribution:

F.M. Jakupova, R.V. Garipova — research design development; preparation of the manuscript;

F.S. Gilmullina — collection of clinical material, manuscript editing;

J.M. Sozinova — research design development, manuscript editing;

M.M. Zagidov — collection of clinical material, development of a questionnaire, obtaining and analyzing survey data, writing a section of a manuscript.

Conflict of interest. Authors declares no conflict of interest.