Eur. J. Epidemiol. 0392-2990
EUROPEAN JOURNAL
November 1992, p. 808-811
Vol. 8, No. 6
Or EPIDEMIOLOGY
ARE HOMES FOR THE ELDERLY STILL A RISK AREA FOR HBV INFECTION? A. FLOREAN1.1, T. BERTIN*, G. SOFFIATI**, R. NACCARATO* and M. CHIARAMONTE* *Department o f Gastroenterology - Institute o f Internal Medicine - Universi(v o f Padova Via Giustiniani, 2 - 35100 Padova - Italy. **Laboratory o f Clinical Chemistry-USL 8 - Vicenza - Italy.
Key words: HBV infection - Elderly - Institutionalization To verify whether improvements in hygiene affect the risk of HBV infection, a seroepidemiological survey on HBV infection was carded out in a home for the elderly with continuous-care accomodation. HBV serum markers were tested in 315 subjects and the results of HBV infection were compared to those observed in two different types of nursing homes for the elderly from an earlier seroepidemiological study carded out in 1978. In addition, results from a cohort of a pre-geriiatric population living in their own homes in the same geographical area surveyed in 1980 were compared to the present study. A statistically significant lower prevalence of HBV serum markers in the new home for the elderly compared to the two types studied in 1978 was observed. No difference was found between the new institutionalized study group and the cohort of a pre-geriatric population surveyed in 1980. These results reflect the improved sanitation in homes for the elderly and show that the elderly have very few opportunities to become infected, even in a close cohabitation system.
INTRODUCTION
Homes for the elderly are considered institutions at risk for hepatitis B virus (HBV) infection (1, 2). In 1978 we carded out a seroepidemiological study in three different types of institution for the elderly (2). In this study we found serological evidence of HBV infection and an HBsAg carder rate significantly increased in these nursing homes with respect to the non-institutionalized population. We also observed the occurrence of repeated cases of acute hepatitis B between 1976 and 1978 in these types of close contact communities, where the relative risk for acute events increased in subjects who received injections delivered from non-disposable materials. l Corresponding author.
All three institutions showed a high risk for HBV infection and we identified two types of residence: 1) a home for the elderly with hotel characteristics which accomodate subjects with high socio-economic level, where several new infected cases were observed; 2) a nursing home for the elderly accomodating subjects with very low socio-economic backgrounds, where HBV epidemiology reflected immunity due to previous infection. In the last 10 years in Italy the nursing home model for the aged has changed. In addition to the hotel-like homes, there is a model characterized by continuous-care accomodation with good standard conventional care. The aim of this study was to carry out a seroepidemiological study in this new model of home for the aged and compare the results with those
808
Vol. 8, 1992
HBV infection in homes for the elderly
TABLE 1. - HBV serum markers in residents in a home for the aged.
observed 12 years ago in two types of residence for the elderly and in a pre-geriatric cohort from the same geographical area.
Males (n = 74)
MATERIALS AND METHODS HBsAg _+ anti-HBc
Study group We studied 315 subjects (74 males and 241 females) living in a nursing home with continuouscare accomodation. This home was completely rebuilt on the same site of the residence surveyed in 1978. Only 17 out of the 315 subjects (5%) were included in the previous study. The majority of the residents (98%) came from very low socio-economic backgrounds. Men and women cohabited in the same building. All subjects were either single, widowed or divorced, with the exception of four, who were married and cohabited with their spouses. With respect to the nursing home surveyed in 1978, the bedrooms and furniture were completely rearranged; meals are served in small tables and social gatherings have been introduced. All the subjects occupied rooms with two or four beds. The length of residence ranged from 1 month to 19 years (mean 53 months). The results obtained in this study were compared to those observed in 1978 in two groups of institutionalized elderly subjects: 83 subjects (17 males and 66 females) living in a hotel-like residence and 108 subjects (47 males and 61 females) living in a standard nursing home for the elderly as well as to those observed in 286 pre-geriatric subjects living in their own homes in the same geographical area (3).
Females (n = 241)
1 (1.3o/0)
Total (n = 315)
1 (0.4%)
P
2 (0.630/0) ns*
anti-HBs ___ anti-HBc 26 (35.1%)
66 (27.3%)
92 (29.2%)
ns
anti-HBc alone
17
22 (6.90/0)
ns
5 (6.7%)
total HBV
32 (43.2%)
(7%)
84 (34.8%)
116 (36.8%)
ns
* ns = not significant, chi-square test.
Table 2 shows the comparison between the 1978 and 1990 results. In 1978, we observed a similar prevalence of HBV serum markers in the two types of residence, with the exception of a higher prevalence of anti-HBs in the nursing home compared to the hotellike residence (p < 0.01). A statistically significant lower prevalence of all serum markers in the new home for the elderly compared to the previous study was observed. The difference in the prevalence of HBsAg was highly significant (0.95% in the actual study vs 180/0and 8.3% respectively, p < 0.001). Fifteen of the 24 HBsAg-positive subjects in the 1978 survey (62.5%) were HBeAg-positive, 1 had anti-HBe (4.1%) and 8 had a negative reaction for both HBeAg and anti-HBe.
Laboratory methods
TABLE 2. Comparison between HBV infection in the new home for the aged and those surveyed in 1978. -
All subjects agreed to participate in the study after being informed about the objectives. The sera were stored at -20 ° C and subsequently tested for HBV and HCV serum markers. HBsAg, anti-HBs and anti-HBc were determined by the ELISA method (Abbott, Chicago, IL). HBsAg-positive sera were tested for HBeAg/anti-HBe and for anti-HDV by radioimmunoassay (Abbott laboratory, Chicago, IL).
1978
HBsAg _+ anti-HBc
1990
Hotel-like
Nursing home
Nursing home
(n = 83)
(n = 108)
(n = 315)
15 (18°/o)
9 (8.30/0) I
t
Statistical analysis
HBeAg
Results were analyzed using the chi-square test.
anti-HBe
RESULTS
10/15 (66.6%) 1/15 (6.6%)
809
anti-HBc alone
5/9 (55.5%) -
28 (33.7%) 14 (16.8%)
55 (50.9%) I
92 (29.2%) **
14 (12.9%)
_ _ J
22
(6.9%)
** L
57 (69.9%)
J _
_
78 (72.2%) I - ***
l
* = p < 0.05;
2/2 (100%) J
, - - I
[
Tot. HBV
J
***
L _ _
The overall prevalence of any HBV serum marker was 36.8%. Only 2 subjects were found to be HBsAgpositive (0.630/0) (both were anti-HBe-positive), while the prevalence ofanti-HBs + anti-HBc was 29.2%. AntiHBc alone was found in 22 out of 315 subjects (6.90/0) (Table 1). No statistically significant correlation was found between the prevalence of HBV serum markers and sex, length of institutionalization or increasing age.
(0.630/o)
- - J
***
[
anti-HBs _+ anti-HBc
2 ***
** = p < 0.01;
**
J
116 (36.8%) ***
_ _ J J
*** = p < 0.001.
Floreani A. et al.
Eur. J. Epidemiol.
TABLE 3. - Comparison of HBV prevalence in a pregeriatric cohort (1980) and in an elderly institutionalized population (1990). Pre-gefiatfic coho~ (56-65 yrs) (1980) (n=286) HBsAg + anti-HBc
5 (1.7%)
Institutionalized (1990) (n=315) 2 (0.63%)
ns*
anti-HBs _+ anti-HBc
73 (25.5%)
92 (29.2%)
ns
anti-HBc alone
16 (5.6%)
22 (6.9%)
ns
Total HBV
94 (32.8%)
116 (36.8%)
ns
* ns = not significant, chi-square test.
Table 3 shows the comparison between the prevalence of any HBV marker in the institutionalized elderly subjects compared to that observed in a pregeriatric population living in their own home surveyed 10 years ago in the same geographical area. There was no statistical difference in the HBV prevalence between the two groups. DISCUSSION
In this study we observed a significantly lower prevalence of HBV serum markers when compared to that observed in two types of homes for the elderly surveyed 12 years ago. This is in agreement with the trend of decreasing incidence of HBV infection observed in several countries (3, 4). This phenomenon has also been demonstrated in Italy in the adult general population (5) and in children (6). The present study provides evidence that this significant change in the epidemiology of HBV also involves the elderly population. The prevalence of HBV serum markers in our study is similar to that observed in a seroepidemiological survey of the general population in 1980 in a pre-geriatric cohort (56-65 years) from the same town (7). Thus we may assume that our elderly study group represents a part of the same pre-geriatric cohort surveyed 12 years ago. This suggests that the elderly have very few opportunities to acquire new HBV infection, even if living in close contact. Further evidence of the lack of new HBV infections is the low HBsAg prevalence, 0.95% compared to 18°/0 and 8.30/0 (p < 0.001). In our view, this change in the epidemiotogy of HBV is the consequence of improvements in hygienic standards and medical care (disposable needles, gloves, syringes and blades, increased number of bathrooms, etc.). In fact, no cases of acute events have been recorded over 810
the last 12 years, except for one case of sporadic acute non-A, non-B hepatitis. In the previous study we found a surprisingly high prevalence of HBeAgpositive subjects (62.5%), while in 1990 no HBeAgpositive subjects were found. This is in favour of a low risk of HBV spreading within the community. In this region an extensive educational campaign directed towards medical personnel and the general population has been carried out since 1978. This program also included high risk communities such as prisons, institutions for the elderly and for the mentally retarded. Prophylaxis by vaccination has been regularly offered to family contacts since 1985; nevertheless this extensive immunoprophylaxis campaign can possibly explain the decrease of HBV infection only in infants and pre-school children. Thus this survey provides an example of the dramatic decline in the exposure to HBV infection among institutionalized elderly subjects and suggests that the widespread introduction of simple and inexpensive hygienic measures can not only be achieved but can be useful in reducing the impact of parenterally transmitted infection. In addition, no correlation was found between HBV serum markers and the length of residence in a home for the elderly. Thus this type of close contact community is not at high risk for viral infection when the primary strategies are fulfilled. In conclusion, nursing homes for the aged represent close contact communities which concentrate populations with a high prevalence of HBV serum markers acquired during their young and/ or adult life. Close cohabitation might carry a high risk of spread of HBV infection if there is a very high prevalence of HBsAg carrier rate. However, if primary prevention measures are fulfilled, the risk of acquiring HBV acute events is negligible.
Acknowledgements
This study was partially supported by the Regional Center Specialized in the Epidemiology and Prevention of Liver and Pancreatic Diseases (Veneto Region). We are indebted to Dr. A. Pacchioni, health manager of the home for the aged, for his helpful collaboration.
REFERENCES
. Braconier J.H. and Nordenfelt E. (1972): Serum hepatitis at a home for the aged - Scand. J. Infect. Dis. 4: 79-82. . Chiaramonte M., Floreani A. and Naccarato R. (1982): Hepatitis B Virus Infection in Homes for the Aged J. Med. Virol. 9: 247-255. . Papaevangelou G.J. and Roumeliotou A. (1988): Reduction of HBV infections and mass immunization - Lancet 2: 53-54.
Vol. 8, 1992
HBV infection in homes for the elderly
4. Matsuo A., Kusumoto Y., Ohtsuka E., Ohsuru A., Nakamura i1., Tajima H., Shima M., Nakata K., Muro T., Satoh A., Ishii N., Kohjj T. and NagataM S. (1990): Changes in HBsAg carrier rate in Goto Islands, Nagasaki Prefecture, Japan - Lancet 1: 955-957. 5. Mele A., Stazi M.A., Corona R.M., Ferrigno L., Sagliocca L., Palumbo F., Falasca P., Galanti C., Mioraghi A., Rosmini F., Gill O.N., Pasquini P. and SEIEVA collaborating group (1990): Decline of incidence of A, B and non-A, non-B hepatitis in Italy. Results of four years surveillance (1985-88) - Ital. J. Gastroenterol. 22: 274-280.
811
6. Chiaramonte M., Trivello R., Stroffolini T., Moschen M.E., Rapicetta M., Bertin T., Renzulli G., Chionne P., Ciccaglione A. and Naccarato R. (1991): Changing pattern of hepatitis B infection in children: a comparative seroepidemiological study (1979 vs 1989) in north-east Italy - Ital. J. Gastroenterol. 23: 347-350. 7. Trivello Ro, Chiaramonte M., Naccarato R., Renzulli G., Zampieri L., Floreani A., Moschen M.E., Turi L, Fanecco A., Fiaschi E. and Vendramini R. (1982): Epatite virale B: Indagine sieroepidemiologica nel Veneto - Boll. ist. sieroter, milan. 61: 136-143.
EUROPEAN JOURNAL
November 1992, p. 808-811
Vol. 8, No. 6
Or EPIDEMIOLOGY
ARE HOMES FOR THE ELDERLY STILL A RISK AREA FOR HBV INFECTION? A. FLOREAN1.1, T. BERTIN*, G. SOFFIATI**, R. NACCARATO* and M. CHIARAMONTE* *Department o f Gastroenterology - Institute o f Internal Medicine - Universi(v o f Padova Via Giustiniani, 2 - 35100 Padova - Italy. **Laboratory o f Clinical Chemistry-USL 8 - Vicenza - Italy.
Key words: HBV infection - Elderly - Institutionalization To verify whether improvements in hygiene affect the risk of HBV infection, a seroepidemiological survey on HBV infection was carded out in a home for the elderly with continuous-care accomodation. HBV serum markers were tested in 315 subjects and the results of HBV infection were compared to those observed in two different types of nursing homes for the elderly from an earlier seroepidemiological study carded out in 1978. In addition, results from a cohort of a pre-geriiatric population living in their own homes in the same geographical area surveyed in 1980 were compared to the present study. A statistically significant lower prevalence of HBV serum markers in the new home for the elderly compared to the two types studied in 1978 was observed. No difference was found between the new institutionalized study group and the cohort of a pre-geriatric population surveyed in 1980. These results reflect the improved sanitation in homes for the elderly and show that the elderly have very few opportunities to become infected, even in a close cohabitation system.
INTRODUCTION
Homes for the elderly are considered institutions at risk for hepatitis B virus (HBV) infection (1, 2). In 1978 we carded out a seroepidemiological study in three different types of institution for the elderly (2). In this study we found serological evidence of HBV infection and an HBsAg carder rate significantly increased in these nursing homes with respect to the non-institutionalized population. We also observed the occurrence of repeated cases of acute hepatitis B between 1976 and 1978 in these types of close contact communities, where the relative risk for acute events increased in subjects who received injections delivered from non-disposable materials. l Corresponding author.
All three institutions showed a high risk for HBV infection and we identified two types of residence: 1) a home for the elderly with hotel characteristics which accomodate subjects with high socio-economic level, where several new infected cases were observed; 2) a nursing home for the elderly accomodating subjects with very low socio-economic backgrounds, where HBV epidemiology reflected immunity due to previous infection. In the last 10 years in Italy the nursing home model for the aged has changed. In addition to the hotel-like homes, there is a model characterized by continuous-care accomodation with good standard conventional care. The aim of this study was to carry out a seroepidemiological study in this new model of home for the aged and compare the results with those
808
Vol. 8, 1992
HBV infection in homes for the elderly
TABLE 1. - HBV serum markers in residents in a home for the aged.
observed 12 years ago in two types of residence for the elderly and in a pre-geriatric cohort from the same geographical area.
Males (n = 74)
MATERIALS AND METHODS HBsAg _+ anti-HBc
Study group We studied 315 subjects (74 males and 241 females) living in a nursing home with continuouscare accomodation. This home was completely rebuilt on the same site of the residence surveyed in 1978. Only 17 out of the 315 subjects (5%) were included in the previous study. The majority of the residents (98%) came from very low socio-economic backgrounds. Men and women cohabited in the same building. All subjects were either single, widowed or divorced, with the exception of four, who were married and cohabited with their spouses. With respect to the nursing home surveyed in 1978, the bedrooms and furniture were completely rearranged; meals are served in small tables and social gatherings have been introduced. All the subjects occupied rooms with two or four beds. The length of residence ranged from 1 month to 19 years (mean 53 months). The results obtained in this study were compared to those observed in 1978 in two groups of institutionalized elderly subjects: 83 subjects (17 males and 66 females) living in a hotel-like residence and 108 subjects (47 males and 61 females) living in a standard nursing home for the elderly as well as to those observed in 286 pre-geriatric subjects living in their own homes in the same geographical area (3).
Females (n = 241)
1 (1.3o/0)
Total (n = 315)
1 (0.4%)
P
2 (0.630/0) ns*
anti-HBs ___ anti-HBc 26 (35.1%)
66 (27.3%)
92 (29.2%)
ns
anti-HBc alone
17
22 (6.90/0)
ns
5 (6.7%)
total HBV
32 (43.2%)
(7%)
84 (34.8%)
116 (36.8%)
ns
* ns = not significant, chi-square test.
Table 2 shows the comparison between the 1978 and 1990 results. In 1978, we observed a similar prevalence of HBV serum markers in the two types of residence, with the exception of a higher prevalence of anti-HBs in the nursing home compared to the hotellike residence (p < 0.01). A statistically significant lower prevalence of all serum markers in the new home for the elderly compared to the previous study was observed. The difference in the prevalence of HBsAg was highly significant (0.95% in the actual study vs 180/0and 8.3% respectively, p < 0.001). Fifteen of the 24 HBsAg-positive subjects in the 1978 survey (62.5%) were HBeAg-positive, 1 had anti-HBe (4.1%) and 8 had a negative reaction for both HBeAg and anti-HBe.
Laboratory methods
TABLE 2. Comparison between HBV infection in the new home for the aged and those surveyed in 1978. -
All subjects agreed to participate in the study after being informed about the objectives. The sera were stored at -20 ° C and subsequently tested for HBV and HCV serum markers. HBsAg, anti-HBs and anti-HBc were determined by the ELISA method (Abbott, Chicago, IL). HBsAg-positive sera were tested for HBeAg/anti-HBe and for anti-HDV by radioimmunoassay (Abbott laboratory, Chicago, IL).
1978
HBsAg _+ anti-HBc
1990
Hotel-like
Nursing home
Nursing home
(n = 83)
(n = 108)
(n = 315)
15 (18°/o)
9 (8.30/0) I
t
Statistical analysis
HBeAg
Results were analyzed using the chi-square test.
anti-HBe
RESULTS
10/15 (66.6%) 1/15 (6.6%)
809
anti-HBc alone
5/9 (55.5%) -
28 (33.7%) 14 (16.8%)
55 (50.9%) I
92 (29.2%) **
14 (12.9%)
_ _ J
22
(6.9%)
** L
57 (69.9%)
J _
_
78 (72.2%) I - ***
l
* = p < 0.05;
2/2 (100%) J
, - - I
[
Tot. HBV
J
***
L _ _
The overall prevalence of any HBV serum marker was 36.8%. Only 2 subjects were found to be HBsAgpositive (0.630/0) (both were anti-HBe-positive), while the prevalence ofanti-HBs + anti-HBc was 29.2%. AntiHBc alone was found in 22 out of 315 subjects (6.90/0) (Table 1). No statistically significant correlation was found between the prevalence of HBV serum markers and sex, length of institutionalization or increasing age.
(0.630/o)
- - J
***
[
anti-HBs _+ anti-HBc
2 ***
** = p < 0.01;
**
J
116 (36.8%) ***
_ _ J J
*** = p < 0.001.
Floreani A. et al.
Eur. J. Epidemiol.
TABLE 3. - Comparison of HBV prevalence in a pregeriatric cohort (1980) and in an elderly institutionalized population (1990). Pre-gefiatfic coho~ (56-65 yrs) (1980) (n=286) HBsAg + anti-HBc
5 (1.7%)
Institutionalized (1990) (n=315) 2 (0.63%)
ns*
anti-HBs _+ anti-HBc
73 (25.5%)
92 (29.2%)
ns
anti-HBc alone
16 (5.6%)
22 (6.9%)
ns
Total HBV
94 (32.8%)
116 (36.8%)
ns
* ns = not significant, chi-square test.
Table 3 shows the comparison between the prevalence of any HBV marker in the institutionalized elderly subjects compared to that observed in a pregeriatric population living in their own home surveyed 10 years ago in the same geographical area. There was no statistical difference in the HBV prevalence between the two groups. DISCUSSION
In this study we observed a significantly lower prevalence of HBV serum markers when compared to that observed in two types of homes for the elderly surveyed 12 years ago. This is in agreement with the trend of decreasing incidence of HBV infection observed in several countries (3, 4). This phenomenon has also been demonstrated in Italy in the adult general population (5) and in children (6). The present study provides evidence that this significant change in the epidemiology of HBV also involves the elderly population. The prevalence of HBV serum markers in our study is similar to that observed in a seroepidemiological survey of the general population in 1980 in a pre-geriatric cohort (56-65 years) from the same town (7). Thus we may assume that our elderly study group represents a part of the same pre-geriatric cohort surveyed 12 years ago. This suggests that the elderly have very few opportunities to acquire new HBV infection, even if living in close contact. Further evidence of the lack of new HBV infections is the low HBsAg prevalence, 0.95% compared to 18°/0 and 8.30/0 (p < 0.001). In our view, this change in the epidemiotogy of HBV is the consequence of improvements in hygienic standards and medical care (disposable needles, gloves, syringes and blades, increased number of bathrooms, etc.). In fact, no cases of acute events have been recorded over 810
the last 12 years, except for one case of sporadic acute non-A, non-B hepatitis. In the previous study we found a surprisingly high prevalence of HBeAgpositive subjects (62.5%), while in 1990 no HBeAgpositive subjects were found. This is in favour of a low risk of HBV spreading within the community. In this region an extensive educational campaign directed towards medical personnel and the general population has been carried out since 1978. This program also included high risk communities such as prisons, institutions for the elderly and for the mentally retarded. Prophylaxis by vaccination has been regularly offered to family contacts since 1985; nevertheless this extensive immunoprophylaxis campaign can possibly explain the decrease of HBV infection only in infants and pre-school children. Thus this survey provides an example of the dramatic decline in the exposure to HBV infection among institutionalized elderly subjects and suggests that the widespread introduction of simple and inexpensive hygienic measures can not only be achieved but can be useful in reducing the impact of parenterally transmitted infection. In addition, no correlation was found between HBV serum markers and the length of residence in a home for the elderly. Thus this type of close contact community is not at high risk for viral infection when the primary strategies are fulfilled. In conclusion, nursing homes for the aged represent close contact communities which concentrate populations with a high prevalence of HBV serum markers acquired during their young and/ or adult life. Close cohabitation might carry a high risk of spread of HBV infection if there is a very high prevalence of HBsAg carrier rate. However, if primary prevention measures are fulfilled, the risk of acquiring HBV acute events is negligible.
Acknowledgements
This study was partially supported by the Regional Center Specialized in the Epidemiology and Prevention of Liver and Pancreatic Diseases (Veneto Region). We are indebted to Dr. A. Pacchioni, health manager of the home for the aged, for his helpful collaboration.
REFERENCES
. Braconier J.H. and Nordenfelt E. (1972): Serum hepatitis at a home for the aged - Scand. J. Infect. Dis. 4: 79-82. . Chiaramonte M., Floreani A. and Naccarato R. (1982): Hepatitis B Virus Infection in Homes for the Aged J. Med. Virol. 9: 247-255. . Papaevangelou G.J. and Roumeliotou A. (1988): Reduction of HBV infections and mass immunization - Lancet 2: 53-54.
Vol. 8, 1992
HBV infection in homes for the elderly
4. Matsuo A., Kusumoto Y., Ohtsuka E., Ohsuru A., Nakamura i1., Tajima H., Shima M., Nakata K., Muro T., Satoh A., Ishii N., Kohjj T. and NagataM S. (1990): Changes in HBsAg carrier rate in Goto Islands, Nagasaki Prefecture, Japan - Lancet 1: 955-957. 5. Mele A., Stazi M.A., Corona R.M., Ferrigno L., Sagliocca L., Palumbo F., Falasca P., Galanti C., Mioraghi A., Rosmini F., Gill O.N., Pasquini P. and SEIEVA collaborating group (1990): Decline of incidence of A, B and non-A, non-B hepatitis in Italy. Results of four years surveillance (1985-88) - Ital. J. Gastroenterol. 22: 274-280.
811
6. Chiaramonte M., Trivello R., Stroffolini T., Moschen M.E., Rapicetta M., Bertin T., Renzulli G., Chionne P., Ciccaglione A. and Naccarato R. (1991): Changing pattern of hepatitis B infection in children: a comparative seroepidemiological study (1979 vs 1989) in north-east Italy - Ital. J. Gastroenterol. 23: 347-350. 7. Trivello Ro, Chiaramonte M., Naccarato R., Renzulli G., Zampieri L., Floreani A., Moschen M.E., Turi L, Fanecco A., Fiaschi E. and Vendramini R. (1982): Epatite virale B: Indagine sieroepidemiologica nel Veneto - Boll. ist. sieroter, milan. 61: 136-143.
