5/8/2012

1

Hotel Dieu – Paris 1500

http://www.nlm.nih.gov/

1st recorded outbreak of childbed fever - 1746

• Variable incidence – epidemics

– higher among women who delivered in hospital

• Mortality 20-80%

• Pathogenesis

– Miasma vs contagion

• 1843, Oliver Wendell Holmes

– “Contagiousness of puerperal fever”

– Doctors should wash their hands

Puerperal fever – an 18th century EIDIgnaz Semmelweis,

Vienna General Hospital,

1846

• Childbed fever mortality:

• Pathologist dies after autopsy!

Hand hygiene mandated

• Infection rates fell

• but Semmelweiss

shunned

Old

Hungarian

proverb: “Tell

the truth, and

people will

bash in your

head”

Fever hospitals – 18th & 19th centuries

London Smallpox Hospital 1746

• Public demand– to limit spread; research

• Built on city outskirts• Variable outbreak activity

– smallpox, scarlet fever, diphtheria, typhus

5/8/2012

2

Australian fever hospitals

Prince Henry (The Coast) Hospital 1881 - ??

Fairfield Infectious Diseases (Queen’s Memorial)

Hospital, Melbourne 1904-1996

Demise of fever hospitals - mid 20th

century

• Control of epidemic diseases by immunisation

– e.g. smallpox, diphtheria, polio, measles, pertussis

• Antibiotic treatment of bacterial infections

– e.g. scarlet fever, pneumonia, TB

• Intensive care in general hospitals

• Intubation/ventilation for respiratory failure;

• Circulatory support for septic shock

• 1970 – Germany

• Returned traveller (from Pakistan) - with fever

– January 10: admitted to isolation room - ?typhoid

• January 14 – rash; cough; oral ulceration

• January 16 - confirmed as smallpox

– transferred to special smallpox hospital

Can communicable diseases be managed in

general hospitals?

Wehrle et al, Bull World Health Org. 1970;43:669-79

Outbreak!

• Period of infectiousness - Jan 13-16

• Contacts vaccinated (if possible)

16 cases (12 patients; 3 nurses & 1 visitor)

10-22 d after exposure

2 secondary cases

• ?AIRBORNE

SMOKE TEST

Smoke flowed from

isolation room (1):

- into waiting area

& up central

stairwell;

- out window &

into those above

Hospital outbreaks of communicable

diseases – 20th & 21st century

• Respiratory viruses (including influenza)– staff; elderly, very young and immuno-compromised

patients

• Measles, pertussis, varicella– unimmunised staff; vulnerable patients

• Vomiting & diarrhoea– Rotavirus (children); norovirus – elderly & staff

Many could be prevented by HCW immunisation

(& hand hygiene & isolation precautions)

--

5/8/2012

3

Another (plausible) outbreak –

Sydney 2002

• 35 year old male

– admitted to hospital Feb 2nd

• 24 hour history of:

– fever, rigors, vomiting, confusion, haemoptysis

• Treated empirically for severe pneumonia

– Day 2 – worse; transferred to ICU

– Day 3 – died

--

Biphasic outbreak – 30 cases 5 deaths

--

1st Index case – hospital 1 2nd Index case – hospital 2

10 relatives; 8 HCW infected 2 relatives;

4 neighbours;

3 nurses; 1 nurse’s

relative infected

?Diagnosis

• Index case - no diagnosis

– blood cultures not taken

• Mother and wife - blood cultures Feb 5th

• Gram negative rod isolated - Feb 6th

– Not easily identified

– Sent to reference laboratory

??Yersinia pestis - plague

– Confirmed February 9th

--

?Plague – is this plausible?

• Where has index patient been?

– Indian student; returned from visit to relatives

– Hunting on day before departure; killed and

skinned wild animal!

– Onset of illness 2 days after return (IP 4 days)

• In fact outbreak occurred in India

– Could have happened anywhere!

Joshi et al. Trans Roy Soc Trop Med Hyg 2009;103:455-6

--

SARS, 2003

• Chinese doctor with

SARS – Metropole

Hotel, Hong Kong.

• In 24 hours - 12

people infected.

• Spread to Vietnam,

Canada, Singapore,

USA, Ireland.

30-65% of SARS cases were

HCWsRisk factors for SARS in HCW

Sun Yat-Sen Hospitals, Guangzhou

Odds

ratio

Caring for super-spreaders 3.6

Performing intubation 2.8

Single vs double gloves 4.1

Natural ventilation +/- fan vs air

conditioning

0.4

Avoiding face-to-face contact (always) 0.3

Chen W-Q et al, BMC Public Health 2009, 9:81

5/8/2012

4

Lessons from SARS

• Multiple routes of transmission

– Hands, fomites - excreted in faeces

– Aerosol & droplets - confusion about mask use

• type, need for fit-testing

• Poor compliance with infection control

– Until HCWs died

– Limited knowledge; fatigue

Post SARS (and H1N1) – cough etiquette

How well do we prevent nosocomial

spread of (E)IDs in 2012?

• After 165 years

– HCW hand hygiene compliance ~30-60%

• HCW influenza immunisation uptake - ~40%

• Cough etiquette for patients (?only) before

‘flu season; ??for HCWs, relatives

• HCW still work when symptomatic

• New hospitals built with few isolation rooms

What do we still need to learn?

• Improved, faster diagnosis

• Dynamics of bioaerosols– Masks; airflows; ventilation

• HCW (as well as patients & visitors):– “Victims & vectors” of (E)ID

• Determinants of compliance– behavioural; organisational; environmental;

cultural