1. Expert Doctor’s Showcase
Infection at the work place – we can
prevent it!
Dr Leong Hoe Nam
Infectious Diseases Physician
Raffles Hospital, Singapore
hoe_nam@yahoo.com.sg
Unrestricted Educational Grant from

2. Financial Declaration
• Advisory Board
– Pfizer
– GlaxoSmithKline
– Sanofi-Pasteur
– MSD
• Site Principal Investigator
– Sanofi-Pasteur – Dengue Vaccine Trial
Unrestricted Educational Grant from

3. Infection in the Workplace is
PREVENTABLE
Begins with
PERSONAL RESPONSIBILITY
Stephen Covey’s 7 Habits of Highly
Effective People

5. SILVER WORKFORCE
• Co-morbidities
– Diabetes Mellitus, Chronic Obstructive Airway
Disease, Asthma, Heart Disease, etc
• Reduced Immunity
• Same medical condition – HIGHER MORTALITY

6. INFECTIONS
HIV /
E Coli AIDS
Haemolytic
Uraemic Viruses
Syndrome FUNGI
BACTERIA
GERMS
Listeriosis
Contaminated Cantaloupes

7. RECENT EPIDEMICS / PANDEMICS
• Spread Fast
• Made use of Airport Routes

8. www.airliners.net

9. RECENT EPIDEMICS / PANDEMICS
• Spread Fast
• Made use of Airport Routes
• Humans were the carrier
• SINGAPORE – major airport hub
RESPIRATORY ROUTE!

11. Germany E Coli O104, Beansprout
FAECAL ORAL
TRANSMISSION

12. INFECTIONS
• Risk of infection higher in the
immunocompromised host. Cancer patients
• Diabetes mellitus type 2. Good control helps
“sugar to the white cells is like brandy to an
alcoholic”
The pleasure of it all makes them not want to
work.

13. Two main modes of transmission of
Illness
• FAECAL ORAL
• RESPIRATORY
balkris.blogspot.com

14. Faecal Oral Transmission
粪便口头传输
Viral infection (Rotavirus, Enteroviruses)
Salmonella (Typhoid fever), Shigellosis
Hepatitis A
- diarrhoea.
Chong Kneas — a floating
village over Tonle Sap Great
lake in Cambodia. A child
refills lake water into her
drinking bottle.

16. Faecal Oral Transmission
粪便口头传输

18. Spot the Difference

19. Straits Times
Nov 3, 2011

20. What do I do?
• Keeping the environment clean
– Clearing / wiping down table.
– Eating at the office table

21. • Cover for keyboard.
• Who used the keyboard previously?

22. What do I do?
• Keeping the environment clean
– Clearing / wiping down table.
– Eating at the office table
• Nothing in the mouth except FOOD!
• Washing Hands
• Good toileting habits

23. PATIENTS with CANCER /
Salmonella enteritidis
IMMUNOCOMPROMISED – TAKE
NOTE!
• Ovaries of Hens
• Bacteria enters egg prior to
egg shell formation
• Faecal
contamination
Fresh eggs go
through the same
vent as faeces
Source: salmonellablog.com
Topnews.in

24. Faecal Oral Transmission
粪便口头传输
It’s all about…..
1. Personal hygiene
2. Personal responsibility
3. Using some common sense….
Unwell
1. Seek treatment
2. Rest at home
3. Strict handwashing

25. Respiratory (呼吸)
Influenza / Tuberculosis / Pertussis
Biggest burden – Influenza
(流行性感冒)
Spread by Droplet (通过飞沫传播)
Other respiratory viruses
Respiratory syncytial virus (RSV), parainfluenza, enteroviruses, adenovirus,
coronaviruses, bocavirus, metapeumovirus
Other bacterial infections
Streptococcus pneumoniae, Haemophilus influenzae, Moxarella catarrhalis

26. Respiratory
Spread by droplets
- minimise exposure
- cover cough
- dispose of dirty tissue
- no spitting
- hand hygiene
- surgical mask SEE A DOCTOR!
Stay at home.
Influenza Vaccinations
for those with chronic
Illnesses
Option of antiviral therapy <48hrs for influenza

30. Surgical Masks – THEY WORK!
PREVENTION OF INFECTION
THEY PROTECT THEY PROTECT
THE WEARER! OTHERS!

31. INFLUENZA
COUGH!
20cm
PREVENTS
Transmission
Johnson et al. Clin Infect Dis.
(2009) 49 (2): 275-277.

32. Myths on Influenza
• It is a whimpy virus
• It doesn’t kill
• There is no influenza in Singapore
• The influenza vaccination doesn’t work

33. Two FLU SEASONS in SINGAPORE
• BIMODAL APRIL – JULY
NOVEMBER – JANUARY
Follows the Southern and Northen hemispheres
Greater PEAK – APRIL – JULY
Angela Chow et al. EID. Vol 12. No.1 Jan 2006

34. All Cause Death
A
Underlying Pneumonia and Influenza
Underlying Circulatory and Respiratory Deaths
Angela Chow et al. EID. Vol 12. No.1 Jan 2006

35. Influenza – excess death
INFLUENZA is responsible for DEATH in TROPICS
Angela Chow et al. EID. Vol 12. No.1 Jan 2006

37. Every peak of excess death paralleled Influenza peaks
(except 1)

38. An experiment in TTSH
• ALL patients admitted over 48 hour period
tested for influenza
• 10% were positive for influenza by PCR
• 60% had “Influenza-like illness”
• “underrecognition and underdiagnosis of
influenza in hospitals. “
Leo YS et al. Lancet Inf Dis. August 2009

39. An experiment in TTSH
• ALL patients admitted over 48 hour period
tested for influenza
• 10% were positive for influenza by PCR
• 60% had “Influenza-like illness”
• “underrecognition and underdiagnosis of
influenza in hospitals. “
Leo YS et al. Lancet Inf Dis. August 2009

40. INFLUENZA in the AT-RISK
POPULATIONS

42. RR Hospitalisation
• Non-epidemic years 1.1 (1977) 1.0 (1979)
• Epidemic years 5.7 (1976) 6.2 (1978)
• 5 X Increase risk of HOSPITALISATION
• Pneumonia RR 25.6
• Death RR 30.9 (1977)  91.8 (1978)

43. The adjusted rates of excess influenza-associated
hospital admissions for the three diagnoses
combined amounted to 58.5, 20.0, 29.2, and 13.4
per 10,000 populations aged 65 years in 1998,
1999, 2000, and 2001, respectively.
• .

44. Pneumonia / Diabetes Mellitus /
Heart + INFLUENZA
= BAD NEWS
What about children…..?
www.colourtown.com

45. • The risk of INFLUENZA on HOSPITALISATIONs
<6 mo 103.8 1-3y 18.6 5-15y – 4.1
6 – 12 mo 49.6 3-5y 8.6 Excess/10K chn/yr

46. Relationship within the family
Children
Parents Grandparents

47. Children gives “multiple doses”
(exposures) to grandparents
• 1 child can give
multiple doses 
 




48. The Good News…..
We have a vaccine…….

49. In Singapore
A vaccine is just
dead vaccine
lightly salted….

50. Effectiveness of the Vaccine

51. • COPD
• Decrease in ARI /
Hospitalisation /
Mechnical
Ventilation

52. MILD
MODERATE
SEVERE
ALL

53. • Part of PRISMA Study (Prevention of Influenza,
surveillance and management Study). 75,000
• 1999-2000 Influenza A
• Vaccine : Control 1:4

54. Reduction in Death / Hospitalisation

57. BURDEN OF INFLUENZA….
BEYOND THE PATIENT…..

58. The burden of respiratory illness…
• All respiratory illnesses can result in visits,
prescriptions, lost school and work days…
• BUT – INFLUENZA – had more of them…..

59. Burden of Influenza
vs Others
• More
transmissibility in
family
• More
prescriptions
• More medical
visits
• More lost work /
school days

60. Vaccinating the YOUNG to save the OLD
• Mandatory Flu
vaccination in
Children – 1962-87
• Laws relaxed 1987
• Repealed in 1994
• VACCINATION of COMPULSORY
CHILDREN
PROTECTS ELDERLY

61. Vaccine Effectiveness
Adults / Children with Asthma

62. >65 yo
713, 872 person-years observation. VACCINATION
27% reduction HOSPITALISATION (for pneumonia /
influenza (OR 0.73, CI 0.68-0.77)
48% reduction in Risk of Death. (OR 0.52 CI 0.5 – 0.55)

63. • Vaccine effectiveness repeated in Taiwan…..

65. Cost EXcluding Operating Income
PRODUCTIVITY RATE 70 50 30

66. Cost INcluding Operating Income
PRODUCTIVITY RATE 70 50 30

67. Vaccine Safety
Generally safe…
Pain / Ache site of infection
Limited fever post vaccination

68. MOH guidelines on Influenza Vaccination
• Persons aged 65 years and older;
• Residents of nursing homes and other chronic care facilities;
• Adults and children who have chronic disorders of the lungs
or heart, including asthma;
• Adults and children who have required regular medical
follow-up or hospitalization during the preceding year
because of chronic metabolic diseases (including diabetes
mellitus), kidney or blood disorders, or lowered immunity
caused by medications or by the Human Immunodeficiency
Virus (HIV);
• Children and teenagers aged 6 months to 18 years who are
receiving long-term aspirin therapy;
• Women who are in the second or third trimester of
pregnancy.

69. INFECTIONS are transmitted by those
around the patient
 INDIVIDUAL
To Protect!
 


 
 INDIVIDUALs
in contact with
patient
Vaccinations must include the OUTER
PERIMETER – the patients’ contacts!

70. 5- to 19-year-olds are expected to suffer the
highest incidence during the initial epidemic
phase of an emerging infection
Mossong et al. PLoS Med. 2008 Mar 25;5(3):e74.

71. Lessons on influenza
• Children transmit the viruses
• Children pass the infection to others
(YOUR EMPLOYEE / YOURSELF)
 Manhours, medical leave.
• Vaccinating the children of your employee
helps

72. Impact of Annual Influenza Epidemics
• No. of workdays lost
1.5 – 4.9 days / person
lab-confirmed influenza.
Keech and Beardsworth. Pharmacoeconomics. 2008;26(11):911-24
• Lost of productivity
“reduced capacity to work”
5 - 6.2 days
Kavet. Am J Public Health. 1977;67:1063-1070

73. Economics of Workplace Vaccination
• Cost savings….($15 to $995) per vaccinated
employee)
(20% attack rates)
Bruce lee at al. Vaccine. 2010 August 23; 28(37): 5952–5959

74. TWO LARGE RANDOMISED CONTROL TRIALS
TWO WELL RECOGNISED JOURNALS

75. But there are detractors….
• “vaccines are undoubtedly the best preventive
means for clinical influenza in healthy adults.”
• “low effectiveness and high incidence of trivial
local adverse effects that the trade-of is
unfavourable”
• “most cost-effective option is not to take any
action”
Demicheli V et al. Vaccine. 2000 Jan 6;18(11-12):957-1030. Review

76. How much vaccination is enough?
• In an epidemic of influenza
• Computer Modelling
• 20% compliance – MAXIMUM GAIN!
60 Days to complete vaccination 120 Days to complete vaccination
Vaccine Cover Attack Rates Vaccine Cover Attack Rates
100% 0.5% 100% 1.5
50% 0.6% 50% 1.5%
20% 0.7% 20% 1.8%
0% 2.8% 0% 3.8%
Lee et al. Am J Prev Med. 2010 March ; 38(3): 247–257

77. Physical Barriers Help

78. Respiratory Infections
• Influenza biggest burden
• Vaccination helps! $23-25
– Hospitalisation / Deaths
• Influenza has two peaks in Singapore
• Surgical masks can help prevent infections.

79. Barriers to Vaccination
1. Doctor’s Recommendations
2. Perceived benefits
3. Previous vaccinations
4. Convenience to vaccinations eg. Vaccination
programme at workplace, at GP consultation

80. Some parting words
• “If there is any conceivable way a germ can
travel from one species to another, some
microbe will find it,”
William McNeill
Plagues and Peoples

81. The END
Infection in the Workplace is
PREVENTABLE
Begins with
PERSONAL RESPONSIBILITY
(CORPORATE RESPONSIBILITY)

82. Annual Impact of Seasonal Influenza - USA
• 2003 US population 294 million
• 610,660 life years lost
• 3.1 million hospitalised days
• 31.4 million outpatient visits
• Direct medical costs $10.4 billion
• Lost earnings $16.3 billion
• Total Economic Burden $87.1 billion

83. INFECTIONS are transmitted by those
around the patient
 INDIVIDUAL
To Protect!
 


 
 INDIVIDUALs
in contact with
patient
Vaccinations must include the OUTER
PERIMETER – the patients’ contacts!

84. How much vaccination is enough?
• In an epidemic of influenza
• Computer Modelling
• 20% compliance – MAXIMUM GAIN!
60 Days to complete vaccination 120 Days to complete vaccination
Vaccine Cover Attack Rates Vaccine Cover Attack Rates
100% 0.5% 100% 1.5
50% 0.6% 50% 1.5%
20% 0.7% 20% 1.8%
0% 2.8% 0% 3.8%
Lee et al. Am J Prev Med. 2010 March ; 38(3): 247–257

85. Difficulty in Studying Influenza
INFLUENZA INFLUENZA-LIKE ILLNESSES
Lab-confirmed Clinically suspected
low sensitivity Other viruses responsible.
Characteristic features (50%)
URTI only (30%)
No Symptoms (20%)
Costly!
Parainfluenza 1,2,3 Respiratory Syncytial
INFLUENZA A, B Virus, Adenovirus, Enterovirus,
Coronaviruses, Mycoplasma

86. Risk of Guillain Barre Syndrome
• Incidence GBS – 4-10/ 1,000,000
• Flu – 15-20% of the cases.

87. • “the attributable rate of GBS would be 0.71
per 100,000 person-years, corresponding to
an attributable risk of 0.8 excess cases of GBS
per 1 million vaccinations.“

88. Impact of Annual Influenza Epidemics
• No. of workdays lost
1.5 – 4.9 days / person
lab-confirmed influenza.
• Lost of productivity
“reduced capacity to work”
Keech and Beardsworth. Pharmacoeconomics. 2008;26(11):911-24