Knowledge and practice concerning severe acute respiratory syndrome among the institutionalized elderly in Hong Kong

Leo Lui 呂志侯, Jennifer H W Chung 鍾曉樺, Winnie W Y Chung 鍾穎宜, Yuk-Wah Hung 洪煜華, Jennifer K Y Ko 高嘉意, Wai-Chee Lo 盧慧芝, Ray S Y Wu 胡尚勇, Raymond C H Yau 游正軒, Chi-Yui Yung 翁梓銳

HK Pract 2005;27:134-141

Summary

Objective: To explore the knowledge and practices concerning prevention of Severe Acute Respiratory Syndrome (SARS) among the institutionalized elderly in Hong Kong.

Design: A cross-sectional analytical study with face-to-face interviews carried out from January 2004 to April 2004.

Subjects: 336 elderlies from 35 old-age homes, which were randomly chosen from the 730 homes licensed by the Social Welfare Department in Hong Kong

Main outcome measures: (1) The level of knowledge about SARS among the institutionalized elderlies in Hong Kong. (2) Changes (if any) in preventive practices among these elderlies before and after the local SARS outbreak in 2003. (3) The relationship between the level of knowledge and the frequency of adoption of preventive practices among the elderlies.

Results: After conducting the interviews, we obtained three main results: Firstly, an inverse relationship was present between age and level of knowledge among the institutionalized elderly. Secondly, most of the elderly were able to recognize the symptom complex of SARS, and were thus likely to seek early medical advice. Last but not least, a majority of the respondents did not change their behaviours before and after the SARS outbreak in terms of adoption of preventive measures (e.g. mask wearing and hand washing).

Conclusion: The relatively low level of awareness of the disease indicated that relevant educational intervention is necessary. It might be effective to direct such intervention at the staff of the institutions.

Keywords: Elderly; Old-age homes; Hong Kong; Knowledge and Practice; Severe Acute Respiratory Syndrome (SARS)

摘要

目的： 探討香港長期院舍長者有關嚴重急性呼吸系統綜合症(SARS)的知識和預防習慣。

設計： 二零零四年一月至四月期間，以面談形式進行的橫切面分析調查。

研究對象： 從香港社會福利署註冊的七百三十間護老院舍中，經隨機抽樣方式，選出三十五間院舍中的三百三十六位長者。

主要測量內容： (1)香港長期院舍長者有關SARS的知識水 平。 (2)比較二零零三年本地SARS疫症爆發前後，該些長者的預防習慣有否改變。 (3)該些長者的知識水平與他們接受預防習慣的頻率。

結果： 會談後，得到三個主要結果。第一，長期院舍長者的年齡與知識水平成相反關係。 第二，大多數長者能夠識別SARS的病徵，而及早就醫。最後，比較在SARS疫症爆發前後， 大多數長者在採取預防措施方面，如配戴口罩和手部清潔，都沒有改變。

結論： 院舍長者的疾病認識水平較低，因此，需要採取適當的教育。有效的方法是向院舍職員提供教育。

主要詞彙： 長者，護老院舍，香港，知識和習慣，嚴重急性呼吸系統綜合症SARS。

Introduction

The emergence of Severe Acute Respiratory Syndrome (SARS) was a major challenge to mankind in many regions of the world. SARS first appeared in November 2002. Through air travel, it rapidly spread from its origins in Guangdong Province, China to many regions outside of China. The outbreak of SARS first reached Hong Kong with the arrival of a visitor from southern China on 21 February, 2003.¹ Within weeks it had spread within Hong Kong and thence globally to affect over 25 countries across five continents. The unprecedented speed of its spread alarmed health care workers and government officials worldwide. Such rapidity and its associated morbidity indicated that the agent responsible was highly infectious and virulent.³

There was strong evidence that SARS, being caused by a novel virus, spread mainly through respiratory droplets and direct contact with a patient's secretions.^16,17 Transmission in most cases was associated with close contact with a SARS case.¹⁵

Age was strongly associated with mortality.^4,5,19 The majority of deaths were among those aged 60 or above or individuals with co-morbid conditions. Studies of Hong Kong's cases showed that the fatality rate for cases 60 years or above was 55% and 6.8% for those below 60 years.⁵ The results were somewhat similar to figures reported in Toronto. Older patients with SARS more often presented with nonspecific symptoms and were more likely to develop secondary nosocomial infections, be admitted to an intensive care unit, and require mechanical ventilation.³ The case fatality rate among those who were already hospital inpatients before the SARS outbreak or those with pre-existing chronic illness was even higher.

Elderly persons residing in old-age homes in Hong Kong are constantly exposed to a congested environment where large numbers of individuals live in close proximity with each other. The sharing of facilities and questionable hygiene in some of these homes potentially enhances the spread of respiratory infections. At the time of the SARS outbreak, the initial asymptomatic incubation period of 7-14 days and the non-specific symptoms of fever and malaise as typical presentations meant that the infection easily passed unnoticed until it was too late, and resulted in an outbreak, and ultimately a tragedy.

There are about 50,000 elderly persons living in 730 old-age homes in Hong Kong.²⁰ Fifty-four of these homes (7.2%) reported residents contracting the disease.⁵ In addition, 11 staff members working in these homes were also infected and two died.5

Given the vulnerability of the selected population of institutionalized elderly persons, preventive measures are particularly important. Knowledge of the disease and appropriate preventive measures are crucial to minimizing the risk of infection in the elderly population. According to local authorities,²¹ certain modifications in practice have proven to be useful in lowering the risk of infection, including advice that (1) people pay careful attention to their personal hygiene and wash hands frequently; (2) people with respiratory tract infections, or those caring for them, wear a facemask; (3) furniture be thoroughly and frequently cleaned with disinfectant or diluted bleach (i.e. thorough disinfection of infected areas against environmental hazards was found to be helpful).

A prerequisite for understanding the need for infection control is a reasonable level of knowledge about the disease and its potential for transmission. Although the last confirmed case of SARS occurred more than a year ago, Hong Kong's elderlies remain a vulnerable population and it appears appropriate and important to maintain vigilance against future possible outbreaks of infectious diseases⁵ of the same or similar nature within old-age homes.

In this context, the overall objective set for this study was to explore the knowledge and practices in the prevention of SARS in currently institutionalized elderly persons, with the aim of devising improved infection control measures applicable to such a population.

Methods

We carried out a cross-sectional analytical study in which respondents were recruited from 35 old-age homes, randomly chosen from the 730 homes licensed by the Social Welfare Department in Hong Kong.²⁰ As many residents as possible in each home were approached at a particular time of the day (chosen at convenience) and invited to participate in the study by means of a face-to-face interview. Informed consent was obtained from all participants prior to the interview. Inclusion criteria were age 65 or older, residence in Hong Kong for more than 7 years and speak Cantonese, Putonghua (Mandarin) or English. Those with communication barriers, documented dementia, having impaired cognitive function or psychiatric disease were excluded from the study. The interviews were administered mainly in Cantonese (the dialect most commonly used in Hong Kong), with a minority number in Mandarin.

Data were collected from January 2004 to April 2004. A pilot study involving about 20 elderlies at one of the randomly chosen homes was carried out in early January before actual field work. Thereafter small changes to the questionnaires were made, including phrasing of the questions to facilitate better understanding by the elderly, a review of the choices provided, as well as standardization of tones and words used by the interviewers when directing questions.

A total of 336 respondents were recruited after excluding the relatively large number of elderlies who were unsuitable. They were interviewed individually to answer questions related to their demographics, knowledge of SARS, the effectiveness and changes in preventive practices after the outbreak as well as their attitude towards it.

Interviewers provided examples of circumstances in which these preventive practices might be used (e.g. residents were asked if they used masks when they needed to go to public places including hospitals; usage of alcohol was asked in relation to the cleaning of household items).

In order to assess knowledge about SARS, questions were asked about the aetiology, symptoms, mode of transmission and incubation period.^7-12 For the "cause of SARS" and "mode of transmission", the respondent was free to give any answer, which would be recorded as "correct" or "incorrect". For "symptoms of SARS", only 2 responses _ "yes" or "no" _ were available after a specific "symptom" was provided by the interviewer. For "incubation period", choices were given as various number of days. Every correct answer was assigned a score of 1, while an incorrect answer was given a 0. The individual scores were summed up to give a total score for knowledge level, which could then be used for comparison with various demographic parameters and health practices, using One-way ANOVA at 95% confidence interval as the statistical model.

Ethics approval was obtained from the Faculty of Medicine Ethical Committee, University of Hong Kong, which conformed to the principles embodied in the Declaration of Helsinki.

Results

Demographic parameters of the sample included age, gender, financial status (in terms of comprehensive social security assistance (CSSA) or income from relatives), living environment during the SARS outbreak in 2003, education level and others. The age of the elderly ranged from 65 to above 85, and 66 % were female (Figure 1). Sixty-six percent received CSSA as part or all of their income, and nearly 80% had lived in an institution at the time of the SARS outbreak for more than one year. The remainder stayed with their family or lived alone. In terms of education, 78% had attained primary level or below, 12% secondary and the remaining had tertiary or other forms of education.

Table 1 shows the percentages of the responses to questions assessing their knowledge about SARS. Correct answers to the questions were: cause of SARS _ virus; symptoms of SARS _ fever, rigor, headache, myalgias, cough, without sputum, melena, visual disturbance or weight loss; mode of transmission _ droplet; incubation period _ 5 to 10 days.

When comparing demographic parameters with level of knowledge, age of the subject was found to be significant (p = 0.023 at 95% confidence interval, One-way ANOVA) and there was an inverse relationship with the mean score of knowledge (Table 2). On the other hand, nearly 72% of respondents identified the mass media as their major source of information about SARS, followed by 32.7% who obtained most of their information from the nursing staff. Seventy-five percent felt that they did not possess sufficient knowledge of the disease.

Another objective of the study was to determine personal hygiene and health practices among the institutionalised elderly population, before and after the SARS outbreak. In order to examine this, several preventive measures were chosen as parameters including: measurement of body temperature, wearing of surgical masks, hand-washing, cleaning with alcohol, diet and exercise, avoiding sharing public utensils, showering, avoidance of public places, getting a "SARS vaccine", use of vinegar, indoor ventilation and the use of herbal medicine. Perception of effectiveness, and the frequency of use of such measures before and after the SARS outbreak were assessed by providing graded choices to the interviewees. The percentage of elderlies who considered these measures to be useful or very useful were as follows: temperature (90%), mask (74%), hand-washing (74%), cleaning with alcohol (65%),¹⁸ diet (65%), exercise (68%), avoidance of shared utensils (63%), showering (62%), avoidance of public places (66%), "SARS vaccine" (44%), vinegar (18%), ventilation (78%) and herbal medicine (35%).

To explore how the SARS outbreak in 2003 changed the health behaviour of the institutionalised elderly, a comparison was made by assigning a score to the frequency of adopting preventive practice and calculating the difference before and after the outbreak (Table 3). Most of the elderlies showed no change in their behaviour, although there were some exceptions: such as the wearing of masks (over 37%), taking body temperature (28%) and washing hands more frequently than before (32%).

In order to investigate whether knowledge and preventive practices were associated, statistical analysis (One-way ANOVA, 95% confidence interval) was carried out between the score of knowledge and the frequency of adopting protective measures. It was found that more frequent hand-washing, consumption of a healthy diet and regular exercise had significant relationship with the level of knowledge about the SARS infection (Table 4). Other preventive measures, including wearing masks and cleaning with alcohol, did not have any significant relationship to knowledge level.

Discussion

Prevention is said to be the best form of treatment. This is especially true in the context of the high mortality risk1-5 that the elderly in an old-aged home face in an outbreak such as SARS. It is, therefore, important to target this elderly population and educate them about the disease and the means for prevention.

The results of our study revealed that Hong Kong's elderly generally had some knowledge about SARS, but the level was still largely unsatisfactory. For example, fever was correctly identified only in 67%, and cough in 58% of the subjects as presenting symptoms for SARS. More technical aspects, such as the mode of transmission or the causative agent, were not as well understood. There was also some confusion as to whether sputum production (44% answered 'yes') was a symptom of SARS. The current literature suggests that this is not a common symptom.^7-12 Nevertheless, other negative symptoms were mostly correctly excluded by those surveyed in the study.

The use of vinegar (fumes from its vaporization were thought to be antiseptic) and certain herbal medicines were widely rumoured at the time of the outbreak to be effective against SARS. Thus, it was somewhat surprising to find most of the subjects were skeptical of these practices _ a majority of the elderly did not believe the use of vinegar and herbal medicine were effective in preventing SARS, even though most had received little education pertinent to these particular issues.

However, one important misconception existed. Many subjects were not aware that there was no available vaccine for SARS.⁶ The influenza vaccine could have been mistaken as a SARS vaccine. Furthermore, many also believed that the "SARS vaccine" was effective in its protection. The consequences of this type of misconception could be grave as holding a false belief of immunity can result in disregard for preventive measures, placing the subjects at even greater risk of infection.

In terms of demographics, only age was associated with the subject's level of knowledge. This may be because the younger subjects had better memory and had kept in touch more with societal information. In addition, living in an elderly home probably negated the effects of different socioeconomic and family status in affecting the level of knowledge. Furthermore, the subjects' educational level was uniformly low, with 78% having only primary schooling or less. This finding needs to be considered when designing an education programme targeting these elderly population.

We found that only about one third of the subjects reported an increase in adopting preventive measures such as mask-wearing, temperature measurement and hand-washing despite these practices were widely perceived to be effective. We believe this apparent contradiction was primarily because many subjects had, by the time of being interviewed (i.e. at least six months had already gone-by after the last SARS case appeared in Hong Kong), reverted back to the habits which characterized their pre-SARS practices.

In terms of preventive practices, our results showed a significant relationship between level of knowledge and frequency of hand-washing. This may be due to the success of the public health education campaign and is evidence for the successful transfer from simple knowledge to changed behaviour. However, wearing of masks as a preventive measure (which was also widely publicized), was not related to knowledge level. This may be because of the discomfort and increased effort in breathing with the use of masks, particularly among those elderly with chronic obstructive lung disease and impaired lung function. In addition, we found that knowledge level was not correlated with the use of alcohol-based hand-washing, perhaps resulting from the poor availability of these products in the elderly homes.

Although there was a relationship between level of knowledge and healthy diet and exercise, it was unclear if this finding was due to the emphasis of the public health campaign on a healthy lifestyle, or whether subjects with a healthy lifestyle were also more health conscious and paid more attention to the campaigns.

According to our study, the mass media and the staff of the institutions were the elderly's main source of information about SARS. This has implications for future outbreaks of infectious diseases. The government must ensure that the media has accurate and appropriate information which is also simple and easy to understand. In addition, better education is needed for the staff in the institutions, who, being the day-to-day caretakers of the elderly residents, could serve the role of raising the knowledge level and awareness among them by conveying the correct health messages.

There were several limitations to this study. Firstly, due to practical limitations, we interviewed only 343 subjects among 730 elderly homes in Hong Kong. The relatively small sample size could have an effect on the reliability of our data and the ability to detect small but socially or clinically significant changes.

Secondly, there was an unavoidable selection bias within the subjects interviewed. Those with whom we were unable to communicate were excluded (e.g. those with documented dementia and those having language barrier). Also, any disorder affecting speech such as slurring after a stroke created a significant communication problem as some of the elderlies were illiterate, making writing an ineffective means to communicate. These subjects were potentially at greater risk^13,14 for contracting an infectious disease and need to be appropriately considered in any educational intervention during an outbreak.

Lastly, the period of data collection (Jan 04 - Apr 04) coincided with another outbreak of SARS in Beijing at that time¹⁹ which attracted much attention by the mass media. This added reminder could have altered the awareness of SARS among the subjects and / or also affected their responses regarding preventive measures.

Conclusion

We found that although the elderly living in old-age homes had only a basic level of knowledge about SARS, there was nevertheless evidence that they had adopted some preventive practices against the disease. However, with the return of SARS still a possibility, and an effective vaccine is yet to be developed, concern remains as to how we can effectively ensure the elderly population maintain an adequate level of vigilance against SARS.

Acknowledgements

We would like to thank the Department of Community Medicine, The University of Hong Kong for making this project possible, Dr TP Lam for his guidance and comments, and also Miss LC Wong for her invaluable help and support in statistics. We would also like to extend our gratitude to all the old-age homes that kindly permitted us to collect data from their residents.

Key messages

1. An inverse relationship was observed among the elderly population between age and the level of knowledge about Severe Acute Respiratory Syndrome (SARS): the younger the respondent was, the more knowledgeable he or she tended to be.
2. The majority of the elderly population was able to recognize the symptom complex of SARS. This finding meant they were more likely to actively seek early medical assistance in circumstances in which they might have contracted the disease.
3. Most of the elderly showed no change in the use of preventive measures before and after the SARS outbreak in Hong Kong.
4. The low level of awareness of preventive measures warranted better education for the nursing staff, who could in turn convey the health messages to the elderly.