Hospital Infections

The Burden, Prevention and Control

Prof. Abdulkarim Al-Aska

Infectious Diseases Unit, King Khalid University

Hospital

Definition

Hospital acquired– Nosocomial Occurring after admission Neither presenting or incubating at the time

of admission Occasionally the illness may develop weeks

or months after discharge.

History

Earliest Europeans hospitals were established in middle ages

No resemblance to modern hospitals in either structure or function

There were lack of space and shifts were ordered for patients and occasionally more than one patients in beds.

Consequences: Increased physical contact promoting

infection spread The squalid situations led to the hospitals

called ‘’pest houses’’

19TH century reports Surgery almost always followed by infection 60% of limb amputations resulted in fatal

infection

Observation

In 1846 there was differential mortality of childbed fever between 2 obstetrics wards 1 & 2 at University of Geneva.

11.4% vs 2.7%. Investigation was then launched by Ignaz

Phillip Semmelweis who was the director of Obstetrics services

Then Pathologist doing post mortem died of similar illness having nicked his hand with scalpel.

Conclusion from infectious materials.

Hospital staff and students were subsequently ordered to wash their hands with calcium hypochlorite after examining each patients.

Mortality rate dropped from 11.4% to 1.3% in ward 1— decline of 89%.

Hand washing also ordered for ward 2, rate declined by 52%.

This clearly demonstrated the spread and prevention of hospital infection

Ignaz Phillip Semmelweis was later regarded as the Father of Hospital Epidemiology.

The discovery of penicillins in the 30s and 40s led to lower infection rate.

Subsequently MRSA became problem. The 1990s saw the emergence of

Vancomycin resistant Enterococci

Advancement in medicine also posed new challenges like catheter related blood stream infection and ventilator associated pneumonia.

Last two decades, increase number of susceptible patients as a result of survival to immune modifying disease or effect of therapy.

Resulting in patients expose to life threatening diseases due to change in natural or acquired immunities.

Importance of Hosp Infection

Estimates in the 70s, 6-8 per 100 patients admitted.

Additional suffering and mortality for patients Nosocomial infection also increased length of

hospital stay and extra costs to authorities.

Prolongation of Hospital Stay due to Nosocomial Infections in the USA

Infection Site Excess Days

Surgical Wound 6.0

Urinary tract 1.2

Pneumonia 4.0

Bacteremia 7.0

Other sites 4.2

Annual Costs and Benefits of Infection Control Program in a Hypothetical 250-bed Hospital

Estimated reduction of directcosts from infectionsprevented

$246,700

Estimated infection controlprogram expenses

$60,000

Hospital savings $186,700

Each $1000 invested in infection controlwill return $3000 in net direct cost savings

Hospital-acquired Infectionwhy worry?

10-15% of patients will get infected during a stay in hospital

Costs >£1 billion per year in UK A single large outbreak can cost 10-100K

Effects of nosocomial infection– Increased mortality & morbidity– Prolonged hospital stay– Increased drugs bill– Increased staffing costs– Demoralising for staff & patients– Decreased public confidence in hospitals &

doctors

Why is hospital-acquired infection different from community-acquired infection?

Many vulnerable patients in close proximity to each other for prolonged periods of time

Many patients have impaired immunity– After anti-cancer chemotherapy– After transplants– Extremes of age

Many patients have impaired normal physiological defences– Breaches in skin– Implanted foreign bodies (biofilms)– Impaired physiology (Peristalsis, mucociliary

escalator)

Antibiotic-Resistant Infections

Associated with extended illness Longer hospital stay Higher risk for death Increased costs to health system Microbes with mutation for resistance has a

selective advantage to: Survive, proliferate and spread.

Controlling antibiotic prescriptions within hospitals had helped in reduction of resistant organism emergence.

Contact precautions with gowns and gloves had prevented the spread of MRSA and VRE.

Transmission facilitated by hospital staff who rarely:

Wash their hands Disinfect or dispose their clothing Disinfect their equipment

Hand washing

Method

Wet hands with clean (not hot) water

Apply soap

Rub hands together for about 20 seconds

Rinse with clean water

Dry with disposable towel or air dry

Use towel to turn off faucet

Alcohol-based Hand Rubs

Effective if hands not visibly soiled

More costly than soap & water

Method

Apply appropriate (3ml) amount to palms

Rub hands together, covering all surfaces until dry

How consistent are we in washing hands between attending patients?

Recent studies Forty per cent (40%) wash their hands after

contact with a patient before the next. Nurses comply more than doctors Worst compliance regrettably in ICUs.

UTI

Thirty per cent of all nosocomial infections Rate of 1% with single in-out catheterisation Risk of 3 to 6% per catheter-day for

prolonged usage. Higher for females than males Post 10-14 days, half of pateints have

bacteriuria.

NNIS Data (CDC).

E coli Coagulase -ve Staph Enterococcus spp Other fungi P aeruginosa Citrobacter spp Candida spp S aureus K pneumoniae Enterobacter spp Proteus mirabilis

Preventive measures have confirmed the advantage of closed drainage system.

Also the use of silver alloy urinary catheter

Pneumonia

Mainly from aspirated gastric contents. Also from microbes-laden secretions of upper

respiratory tract. Septic emboli from infected CVP or A-V

fistula Rarely, inhalation of pathogens from the air

for example M tuberculosis and Aspergillus fumigatus

S aureus P aeruginosa Enterobacter spp K pneumoniae E coli

Most patients are ventilated in ICU. Rates from 6 to 30%. Risk of 1 to 3% per day. Higher inocula with patients on either H2

blocker or antacid therapy. Less with sucralfate.

Preventive measures: Keeping patients at an angle of 45 degrees. Use of device for subglottic suction to reduce

the pooling of secretions. Led to less clinical aspirations and lower

pneumonia rates.

Surgical Site Infections

Still occur despite aseptic techniques Clearly the obese and diabetic patients

require adequate preparations. Use of dry shaving a day before surgery is

better than clippers hours before. Emergent surgery on inherently

contaminated organs like the colon.

S aureus Coagulase –ve Staph Enterococci E coli Enterobacter Klebsiella Candida

Blood Stream Infections

Primary 80%: mainly from infected vascular catheter.

Secondary 20%: local infection in another organ.

Catheter-related BI begins with colonization of the catheter with microbes.

Femoral more prone than IJ and SC

Cultured tips of catheter in cardiac surgery are infected within 1-2 hours of insertion.

Earlier on tackled by the body’s immune system.

Subsequently microbes moved through the catheter tract to enter the blood stream.

By 10 days there is an increasing frequency of intra-luminal contamination.

Multiple randomised trials had shown that antiseptic preparation with chlorhexidine is far superior in risk reduction of colonisation as compared with alcohol or povidone-iodine preparations.

Chlorhexidine-silver sulphadiazine treated catheter has been shown to reduce colonization and blood stream infection by about half.

Cotton gauze covered by tape were associated with lower risk of colonization versus transparent dressings.

Antibiotic-coated catheter reduced colonization by 55% as compared with standard catheters.

Comparative study had shown that the capacity of minocycline/rifampicin coated catheter were superior in resisting infection versus chlorhexidine-silver sulfadiazine catheter.

Organization for Infection Control

Surveillance Outbreak investigations Education Hospital employee health Antimicrobial utilization Policy development Quality assessment

Infection Control Programs

Size and intensity of program predicts infection rates.

Most effective associated with 32% reduction compared with hospital without program.

One hospital with effective program in 1985 reported saving costs of $2million for the year.

Infection Control in hospital

Interrupt transmission– Human-to-human

Hand washing Ward routine (e.g. wet mopping) Aseptic technique Sterilisation & disinfection Isolation procedures

– Environment Food hygiene, pest control, theatre design

Precautions

StandardSpecific ----Airborne

----Droplets

----Contact

Standard Precautions

Perform hand hygiene Wear gloves Wear gowns Wear a mask and

goggles and glasses

Standard Precautions

Hand hygiene Respiratory hygiene and cough etiquette Personal protective equipment (PPE)

Based on risk assessment to avoid contact with blood, body fluids, excretions, secretions

Safe injection practices Environmental control Patient placement

Specific Isolation Categories

Airborne precautions

Use a negative-pressure room

Keep doors closed Wear grade N95 or

better mask If patient transport is

necessary, then patient to wear surgical mask

TB, Measles, Chickenpox

Droplet precautions

Keep doors closed Wear a surgical mask if

entering the room Discard mask after

leaving the room If patient transport is

necessary, patient to wear surgical mask

Meningitis, Mumps, Pertussis, Rubella

Contact precautions

Wear a gown and gloves to enter the room

Use a dedicated stethoscope and thermometer

Remove gown and gloves before leaving the room

Acute infectious diarrhea, Abscess/draining wound

Occupational Exposures

Occupational Risk for Hepatitis

Hepatitis B is much more frequent occupational infection and a cause of deaths among HCWs.

Standard precautions and vaccination had reduced infection.

Ten per cent of HCWs do not respond to vaccination.

No vaccine yet for Hepatitis C

Occupational exposures General steps in management Wash and clean wounds Flush mucous membranes immediately

Unvaccinated Exposed HCW Injury from HBsAg +ve source, give HBIG

0.06mL per Kg and initiate HB vaccine Injury from HBsAg -ve source, initiate HB

vaccine Injury from unknown status of HBsAg initiate

HB vaccine and determine HBsAg of source.

Vaccinated HCW/unknown Ab status Injury from HBsAg +ve source, do anti- HBS

on exposed person:: --If titer>10milli-IU/ml no treatment. --If titer<10milli-IU/ml, give HBIG 0.06mL per

Kg + 1 dose of HB vaccine

Injury from HBsAg -ve source, no treatment is necessary.

Injury from unknown status of HBsAg do anti-HBS on exposed person::

--If titer >10milli-IU/ml no treatment. --If titer <10milli-IU/ml, give 1 dose of HB

vaccine plus HBIG if source high risk

Hepatitis C exposure

Determine anti-HCV from both exposed person and source.

If source known +ve and exposed –ve follow up HCV testing advised.

Baseline and serial LFTs HCV RNA after 2 weeks of exposure.

No recommended prophylaxis; immune globulin not effective.

Monitor for early infection as therapy may reduce risk of progression to chronic hepatitis.

Risk factors from case control study. Needle from artery and veins. Deep injury. Male HCW. Source ≥ 6 million copies/mL.

Occupational Risk for HIV Infection

Approximately 1 in 300-400 needle sticks injuries will transmit HIV.

Chances increased with large-bore hollow needle

Wash wounds and flush mucous membranes.

Baseline HIV test, CBC, renal and hepatic tests

Viral load of source. HIV testing should be repeated as follows:

3-4 weeks and 3 & 6 months PEP should be started within hours

Regimens Treat for 4 weeks Monitor drug side-effects fortnightly Basic regime Zidovudine + Lamivudine or Stavudine +

Lamivudine Expanded regime Above + Lopinavir + Ritonavir

Occupational Risk for T B

Infection occurs in setting lacking isolation techniques

These are: Absence of negative-pressure ventilation

rooms Lack of administrative control measures

Further recommendations Annual and semi-annual PPD testing Training and retraining of staff

An extract from the work book of Dr Fester, aged 24, newly qualified house officer...

50 lines as punishment for poor hand hygiene

I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients I promise to wash my hands between patients...

Thank you