The risk of hepatitis A infection among healthcare workers: a review of reported outbreaks and sero-epidemiologic studies

An outbreak of hepatitis A associated with salted clams in Busan, Korea

OBJECTIVES

In July 2019, there were multiple reports on patients with hepatitis A among the visitors of a restaurant in Busan. The current study presents the results of an epidemiological investigation and outlines the supplementary measures that would help with hepatitis A control.

METHODS

A cohort study was conducted for all 2,865 customers who visited restaurant A from June to July. Using a standardized questionnaire, participants reported the presence of hepatitis A symptoms and whether they had consumed any of 19 food items. As for participants who had visited public health centers, their specimens were collected.

RESULTS

From the study cohort, 155 participants (5.4%) had confirmed hepatitis A. The epidemic curve was unimodal, and the median number of days from the restaurant visit to symptom onset was 31 days. A genotype analysis indicated that 89 of 90 tested patients had hepatitis A virus (HAV) genotype 1A. The results of a multivariate logistic regression analysis indicated that the ingestion of salted clams increased the risk of hepatitis A by 68.12 times (95% confidence interval [CI], 9.22 to 510.87). In an unopened package of salted clams found and secured through traceback investigation, HAV genotype 1A was detected.

CONCLUSIONS

To prevent people from ingesting uncooked clams, there needs to be more efforts to publicize the dangers of uncooked clams; the food sampling test standards for salted clams should also be expanded. Furthermore, a laboratory surveillance system based on molecular genetics should be established to detect outbreaks earlier.

Evaluation of testing and vaccination status of healthcare workers in Turkey for hepatitis A: A multicenter study

BACKGROUND

This study aimed to investigate the prevalence of the disease and testing and vaccination status of healthcare workers in terms of hepatitis A infection as well as their awareness. This study is a multicenter descriptive study performed with healthcare workers.

MATERIAL AND METHODS

Testing status for hepatitis A, awareness of the results and vaccination status of healthcare workers were compared.

RESULTS

Of the 12,476 healthcare workers participating in the study, only 65% (8,115 healthcare workers) had awareness of hepatitis A test results. Of the participants, 6,481 (66.3 %) stated that they were not vaccinated against hepatitis A. Vaccination rates against hepatitis A decreased with increasing age (P < .01). The rates of vaccination in all departments where participants worked were above 60% (P < .05). While the rate of protection among those working in departments creating a risk for hepatitis A virus infection was higher, no difference among vaccination rates was observed compared with the other departments.

CONCLUSION

Vaccination of seronegative individuals is the safest way for hepatitis A, which can progress to fulminant hepatitis at advanced ages. It must be aimed primarily to increase the awareness of healthcare professionals and to increase the vaccination rates for hepatitis B and hepatitis A for the prevention of viral hepatitis. In our study, the awareness level was found to be above 50%, and the vaccination level was 35%, which is a rate that must be increased.

Hepatitis E in 24 Chinese Cities, 2008-2018: A New Analysis Method for the Disease's Occupational Characteristics

Background: The disease burden of hepatitis E remains high. We used a new method (richness, diversity, evenness, and similarity analyses) to classify cities according to the occupational classification of hepatitis E patients across regions in China and compared the results of cluster analysis. Methods: Data on reported hepatitis E cases from 2008 to 2018 were collected from 24 cities (9 in Jilin Province, 13 in Jiangsu Province, Xiamen City, and Chuxiong Yi Autonomous Prefecture). Traditional statistical methods were used to describe the epidemiological characteristics of hepatitis E patients, while the new method and cluster analysis were used to classify the cities by analyzing the occupational composition across regions. Results: The prevalence of hepatitis E in eastern China (Jiangsu Province) was similar to that in the south (Xiamen City) and southwest of China (Chuxiong Yi Autonomous Prefecture), but higher than that in the north (Jilin Province). The age of hepatitis E patients was concentrated between 41 and 60 years, and the sex ratio ranged from 1:1.6 to 1:3.4. Farming was the most highly prevalent occupation; other sub-prevalent occupations included retirement, housework and unemployment. The incidence of occupations among migrant workers, medical staff, teachers, and students was moderate. There were several occupational types with few or no records, such as catering industry, caregivers and babysitters, diaspora children, childcare, herders, and fishing (boat) people. The occupational similarity of hepatitis E was high among economically developed cities, such as Nanjing, Wuxi, Baicheng, and Xiamen, while the similarity was small among cities with large economic disparities, such as Nanjing and Chuxiong Yi Autonomous Prefecture. A comparison of the classification results revealed more similarities and some differences when using these two methods. Conclusion: In China, the factors with the greatest influence on the prevalence of hepatitis E are living in the south, farming as an occupation, being middle-aged or elderly, and being male. The 24 cities we studied were highly diverse and moderately similar in terms of the occupational distribution of patients with hepatitis E. We confirmed the validity of the new method on in classifying cities according to their occupational composition by comparing it with the clustering method.

Attitudes of Healthcare Personnel towards Vaccinations before and during the COVID-19 Pandemic

Vaccines constitute highly effective tools for controlling and eliminating vaccine-preventable diseases (VPDs) and are assessed to avert between two to three million deaths per year globally. Healthcare personnel (HCP) constitute a priority group for several vaccinations. However, studies indicate significant rates of vaccine hesitancy among them and, therefore, of acceptance of vaccination recommendations. This cross-sectional study was conducted in a university hospital in Southern Italy to assess the knowledge and attitudes of HCP about VPDs before and during the COVID-19 pandemic, estimate their intention to get vaccinated against COVID-19, and search for determinants that may influence their choice. A self-administered questionnaire was used. HCP improved their knowledge about VPDs and were more favorable to vaccinations in September–December 2020 compared to January–December 2019. Overall, 75% of respondents would get a COVID-19 vaccine. Our findings indicate a potential role of the ongoing COVID-19 pandemic on Italian HCP’s knowledge and attitudes towards vaccines.

Nosocomial hepatitis A outbreak among healthcare workers and patients in a community hospital during an ongoing statewide outbreak

OBJECTIVE

The Tennessee Department of Health (TDH) investigated a hepatitis A virus (HAV) outbreak to identify risk factors for infection and make prevention recommendations.

DESIGN

Case series.

SETTING

Community hospital.

PARTICIPANTS

Healthcare workers (HCWs) or patients with laboratory-confirmed acute HAV infection during October 1, 2018-January 10, 2019.

METHODS

HCWs with suspected or confirmed hepatitis A infections were interviewed to assess their exposures and activities. Patient medical records and hospital administrative records were reviewed to identify common exposures. We conducted a site investigation to assess knowledge of infection control practices among HCWs. Serum specimens from ill persons were tested for HAV RNA by polymerase chain reaction (PCR) and genotyped.

RESULTS

We identified 6 HCWs and 2 patients with laboratory-confirmed HAV infection. All cases likely resulted from exposure to a homeless patient with a history of recreational substance use and undiagnosed HAV infection. Breaches in hand hygiene and use of standard precautions were identified. HAV RNA was detected in 7 serum specimens and all belonged to an identical strain of HAV genotype 1b.

CONCLUSIONS

A hepatitis A outbreak among hospital patients and HCWs resulted from exposure to a single patient with undiagnosed HAV infection. Breakdowns in infection control practices contributed to the outbreak. The likelihood of nosocomial transmission can be reduced with proper hand hygiene, standard precautions, and routine disinfection. During community outbreaks, medical providers can better prevent ongoing transmission by including hepatitis A in the differential diagnosis among patients with a history of recreational substance use and homelessness.

[General epidemiology of infections acquired by health-care workers: immunization of health-care workers]

Healthcare workers are exposed to multiple occupational hazards, the most common being the biological risk. Moreover, colonized staff, or those in incubation period, or with an active infectious disease, could be at risk of transmitting these infections to others, such as patients, relatives or other workers. Therefore, measures to prevent biological risks in the healthcare environment are essential. In this chapter, the main recommendations for the prevention and control of infectious diseases that can affect health care personnel are reviewed. Specific measures recommended for each infection, including vaccination guidance, are described. These recommendations were updated according to the available evidence and the epidemiological changes described in recent years.

Acute hepatitis A in an elderly patient after care worker travel to high endemicity country

Hepatitis A virus (HAV) is considered one of the most important vaccine-preventable diseases in travelers. HAV spreads from person to person via the fecal-oral route and gives rise to an estimated 1.4 million cases worldwide each year. In developing countries with poor sanitary conditions people tend to be infected during childhood and have few symptoms, whereas in developed countries with good sanitary conditions fewer people develop immunity during childhood. This leads to susceptible populations of adults, who are also more prone to severe complications. Here we describe two confirmed cases of hepatitis A associated with a nursing home. The index case was a care worker who had recently traveled to a high-endemicity country, and the second case was a resident at the nursing home where the index case worked. Both cases had an identical genotype IIIA strain, consistent with a transmission event. Current policy does not include a requirement for hepatitis A vaccine in care workers who travel to high endemicity countries despite the fact that infected care workers can potentially spread the disease to elderly patients and other groups at risk of severe complications from HAV infection. We suggest that employers should consider hepatitis A vaccine upon employment; particularly in care workers who plan to visit areas where HAV is known to be endemic.

Hepatitis a virus seropositivity in nurses and paramedical personnel at a university hospital in north iran

Background

The status of hepatitis A virus (HAV) among health care workers has not been studied yet in Iran.

Objectives

This study aimed to evaluate the HAV seropositivity among the healthcare personnel in Ayatollah Rohani Hospital, Babol, Iran, according to age, number of working years, and other demographic data.

Patients and Methods

This cross sectional study was performed on all nurses, nurses' aid, and paramedical technicians at Ayatollah Rohani Hospital, Babol, from March 2011 to March 2012. Blood was obtained from all cases (466) and the sera were separated. All serum samples were tested for anti-HAV antibodies (IgG) by enzyme-linked immunosorbent assay (ELISA). Data were analyzed by logistic regression analysis using SPSS software, version 18.

Results

330 out of 466 (71%) persons were positive for anti-HAV antibodies (IgG) with no significant difference between females (71.5%) and males (70%) (P = 0.89, 95% CI. 0.533-2.083). The lowest sero-prevalence rate was observed in the 20-29 year age group (57.8%). Seropositivity for HAV significantly increased with age (P < 0.000, 95% CI. 1.626-3.262), 77.4% for 30-39 years and 85.3% for more than 40 years. The seropositivity rate also increased significantly in accordance with the number of working years (P = 0.012, 95%CI. 1.098-2.170). 110 out of 353 (31.2%) cases were seronegative among those with less than 5 years of working time. An obvious decrease of seronegative rate of HAV was seen in those with 5-10 years (27%) and more than 10 years (14.3%) of working time.

Conclusions

These findings indicate relatively high prevalence rate of HA infection among nurses and paramedical personnel at this hospital. Nevertheless, 30% of the health workers have been seronegative and are still at risk of HA infection development. Considering that the disease has more severe course as age increases, improvement of standard hygiene and prevention strategies are recommended. Furthermore, vaccination may play a significant role in the occupational health policy to protect the susceptible health care workers population in the future.

Hepatitis A antibody seroprevalence among medical school students

A total of 324 first- to third-year medical school students were examined for anti-hepatitis A virus IgG. Of these 324 students, 37 were found to be anti-hepatitis A virus IgG positive (11.4%). Mass screening of medical students for seropositivity and vaccination of nonimmune students should be considered before starting medical clerkships.

Multicentric evaluation of new commercial enzyme immunoassays for the detection of immunoglobulin M and total antibodies against hepatitis A virus

A multicentric clinical study was conducted on representative sera from 1,738 European and U.S. subjects for the evaluation of new anti-hepatitis A virus enzyme immunoassays from Bio-Rad Laboratories. Comparison with reference DiaSorin S.p.A. tests confirmed the good performance of Bio-Rad assays (99.85% and 99.47% overall agreement in detecting total antibodies and IgM, respectively).

[Hepatitis A virus seropositivity among healthcare workers at a university hospital in Korea]

BACKGROUND

Healthcare workers (HCW) are known as a risk group of hepatitis A virus (HAV) infection and vaccination of this group against HAV has been suggested. However, the seroprevalence of HAV antibody among HCW in Korea has not been reported. We investigated the seropositivity of HAV antibody in HCW, to obtain a baseline data.

METHODS

We measured serum total HAV antibody using chemiluminescent immunoassay (ADVIA Centaur, Germany) in 174 HCW at one university hospital in Seoul, Korea.

RESULTS

Serum HAV antibody was positive in 48 (27.6%) of 174 subjects tested. The seropositivity of HAV antibody was significantly increased with increasing age: 21.1% (26/123), 55% (22/40), and 100% (11/11) in the age groups of 20's, 30's, and 40's, respectively (P<0.001). However it was not significantly different among different occupations (physicians 38%, nurses 24.6%, other workers 31.4%, P=0.376) and work places (medical ward 29.1%, pediatric ward 25.9%, emergency room 34.4%, laboratory 0%, P=0.140). The seroprevalence rate of HAV antibody in the age groups of 20's and 30's in this study was not higher than that of previous studies on non-HCW populations in Korea since 2006.

CONCLUSIONS

The seroprevalence of HAV antibody among HCW in the age groups of 20's and 30's in a Korean hospital was not higher than that of non-HCW populations, and the seropositivity increased with increasing age. Further studies are needed for the age-specific strategy for vaccination, considering the increased risk of exposure in HCW to HAV infection in hospital environment with the increase of symptomatic patients with HAV.

Sero-epidemiology of hepatitis A virus infection among healthcare workers in Korean hospitals

Hepatitis A virus (HAV) has been increasingly reported in Korea as has an outbreak in Korean healthcare workers (HCWs). This 2008 study evaluated the sero-epidemiology of HAV infections among 3696 HCWs in four Korean hospitals. HCWs were tested for immunoglobulin G anti-HAV antibodies using commercially available kits. Data including demographic characteristics, occupation, workplace and serological status for other hepatitis viruses were collected. Statistical analyses were conducted to identify variables related to HAV seropositivity. Among the 3696 participants, 2742 (74%) were women and the majority (96%) were aged 20-39 years (median: 28; range: 19-68). Eighteen percent were physicians, 46% nurses, 10% nurses' aides, 11% paramedical technicians and 15% administrative staff. Seropositivity for HAV significantly increased with age (P<0.001): 1.8% for < or =24 years, 14.7% for 25-29 years, 41.8% for 30-34 years, 75.5% for 35-39 years, and 93.7% for > or =40 years. Among those aged 20-39 years, age-specific HAV seroprevalence was significantly lower in physicians than in the other occupational groups (P<0.001). In Korea, mass vaccination to HCWs aged < or =29 years or screening for seropositivity and vaccinating non-immune subjects aged 30-39 years should be considered, especially in physicians.

Specific immunization issues in the occupational health setting

This article looks at the components of an effective occupational health vaccination programme and also reviews the legal basis for them. It addresses the issue of vaccine licensing including pre-clinical, clinical and post-licensing studies. It explores screening for vaccine preventable diseases in the occupational health setting and then addresses particular issues around hepatitis B, chicken pox, tuberculosis, measles, rubella, diphtheria, polio, mumps and hepatitis A.

The shifting epidemiology of hepatitis A following routine childhood immunization program in Israel

OBJECTIVES

In 1999 Israel became the first country to introduce immunization against hepatitis A to its national childhood vaccination program. The study objectives were to assess the uptake of hepatitis A vaccine following the new policy and to examine the incidence of hepatitis A and the number of prevented cases.

METHODS

Data on incidence of hepatitis A and vaccination rates were obtained from a large health maintenance organization in Israel covering 1.6 million members. We identified all members that were diagnosed by a primary care physician as suffering from hepatitis A, had a positive hepatitis A virus-IgM test result, or were hospitalized due to hepatitis A between 1998 and 2004.

RESULTS

The results indicate that 5 years following its inclusion in the national childhood immunization program, vaccination coverage levels with at least one dose of hepatitis A vaccine for children aged under 5 years and 5-14 years were 87% and 51%, respectively. During this period the annual incidence rates declined by 88% from 142.4 to 17.3 per 100,000. The most significant reduction in morbidity was observed among children.

CONCLUSIONS

In endemic areas, vaccination of infants and children against hepatitis A may be efficient to greatly reduce the total burden of the disease.