Intro to Infectious Diseases and Epidemiology of Nosocomial Infection

Arthur Dessi Roman, MD, MTM, FPCP,

FPSMIDInternal Medicine – Infectious Diseases

Infectious Diseases at the Forefront

@gonnabedess @gonnabedess

OutlineI. Why are infectious diseases unique

II. Introduction and Epidemiology of healthcare-associated infections

Most of them are communicable.Case of The Black Death Caused by Yersinia pestis carried by black rats one of the most devastating pandemics in human

history estimated to have killed 30–60% of Europe's

population reducing the world's population from an ~450M to between 350 and 375M in the 14th century

it took 150 years for Europe's population to recover

Why are infectious disease unique?

How infectious is MERS?

Reproduction Number

MERS: Reproduction number

There is sometimes a need for urgency for control.


MERS South Korean South Korean outbreak: May - July 2015

• Index case: 68/M, (+) travel to Bahrain, UAE, Saudi Arabia, and Qatar; diagnosed with MERS 9 days after initial medical consult

• Total of 186 cases with 36 deaths

Korean Centers for Disease Control and Prevention. Available from www.mers.go.kr. Accessed on 11 August 2015.

MERS Economic toll on South Korea

• Department store sales: down by 17% (June 2016)

• No. of people going to the movies, amusement parks, baseball games and museums also recorded large slumps, ranging from 38% to 82%

• No. of trips cancelled: 100,000 foreign travelers

• Tourist arrivals in the first 11 days of the month have fallen by 25%

http://www.businessinsider.com/mers-outbreak-hurting-korean-retail-and-tourism-2015-6

http://www.mers.go.kr/

MERS: What went wrong in Korea?

• MERS unexpected and unfamiliar to most physicians

• Sub-optimal prevention and control measures in some hospitals

• Overcrowding at the ER an in ward rooms

• Patient habits and customs• “Doctor-shopping” - patients seek care at a number of

medical facilities

• Visits to hospitalized patients by many friends and family members.

• “Superspreader”

Training on Hospital Preparedness and Management of MERS

WHO Press release. WHO recommends continuation of strong disease control measures to bring MERS-CoV outbreak in Republic of Korea to an end. 13 June 2015.

Why are infectious diseases unique?

Microbes adapt and evolve.

Clatworthy AE, Pierson E and Hung DT. Targeting virulence: a new paradigm for antimicrobial therapy. Nature

Chemical Biology 3, 541 - 548 (2007) Published online: 20 August 2007 doi:10.1038/nchembio.2007.24

Timeline of antibiotic deployment and the evolution of antibiotic resistance.

They are sometimes occur with environmental, ecological and even behavioral events.

• Ondoy left Metro Manila flooded in September 26, 2009

• DOH: 2,272 leptospirosis cases, 174 deaths between October 1 and November 3, 2009 in 15 hospitals in Metro Manila.

• peak incidence reached

2-3 weeks after


Factors Leading to the Emergence of Infectious Diseases in the 21st Century

Factors Leading to the Emergence of Infectious Diseases in the 21st Century

They know NO boundaries.


Before:9 countries affected (1970)

Now:~50 million dengue infections worldwide every year (WHO)

and 2/5 of the world's population at risk in over 100

countries

attributed to expanding geographic distribution of the

mosquito vectors, predominantly Aedes aegypti

Average annual number of dengue cases reported to the WHO, and of countries reporting dengue, 1955–2007.


• Started in Mexico, with its greatest burden of critical illness and death occurring between March 18- June 1, 2009

• In 6 weeks, it has spread as far as previous pandemic influenza viruses have spread within six months.

• continues to be the dominant influenza virus in circulation in the world comprising more than 60% of all influenza positive specimens reported to WHOInfluenza A(H1N1)

They know NO boundaries.

Why is PH concerned about the threat of EIDs?

•

•

•


3,983,627 tourists (Jan-Sep 2015)

10.76% higher than 2014

46.7 % are foreigner



Disease Associated Etiologic Agent

CAD and stroke Chlamydia pneumoniae, atypical microorganisms, Mycoplasma

Deafness, hearing loss Lassa fever virus

Gastric & duodenal ulcer Helicobacter pylori

Infertility Chlamydia trachomatis

Cervical carcinoma Human papillomavirus

Hepatocellular Ca Hepatitis B and C viruses

Kaposi’s sarcoma HHV-8

Non-Hodgkin’s lymphoma Hepatitis C virus

Lyme arthritis Borrelia burgdorferi

Reactive arthritis Campylobacter jejuni, Salmonella

Guillain-barre syndrome Campylobacter jejuni

They may be associated with malignancies and other chronic diseases.


Host immunity is involved. Intergrity of the immune system (innate immune system,

humoral and cell-mediated immunity)

Extremes of age

State of immunity (vaccination status, presence of co-morbidities)

Presence of immunocompromised state

The Smallpox Threat

• Eradicated in 1979 (WHO)

• Routine vaccination stopped in 1974 (US)

• Last documented case 1949 (US)

• More the 3/4 of the world’s population is now

susceptible


They deal with more than one population.With complex interactions among them

Reservoir

(animals)Dogs

and

sheep/goats –

Echinococcus;

mice and ticks

– Borrelia

Host (e.g. humans)Infectious agents

(helminths,

bacteria, fungi,

protozoa,

viruses,

prions)

Vectors

Mosquito

(malaria), snails

(schistosomiasi

s), blackfly

(onchocerciasis

)

Measures of Disease Frequency

CaseMeasuring disease frequency in populations requires

the stipulation of diagnostic criteria. In clinical practice the definition of "a case" generally

assumes that, for any disease, people are divided into two discrete classes - the affected and the non-affected. For most acquired diseases the real question in

population studies is not "Has the person got it?" but "How much of it has he or she got?"

BMJ. Epidemiology for the uninitiated. Accessed from http://www.bmj.com/about-bmj/resources-readers/publications/epidemiology-uninitiated/2-quantifying-disease-populations


“Case Definition” A set of uniform criteria used to define a disease for

public health surveillance. Enable public health to classify and count cases

consistently across reporting jurisdictions, and should not be used by healthcare providers to determine how to meet an individual patient’s health needs.

http://wwwn.cdc.gov/nndss/case-definitions.html


“Case Definition” Should be precise and unambiguous Essential to define and standardize the methods of

measuring the chosen criteria.



Prevalence no. of cases of disease at a particular point in time includes old and new cases better in detecting burden of disease in a particular

population

In the Philippines, what is the prevalence of HIV among MSM?

A. <1%

B. 12%

C. 30%

D. 51%

Question

~12 positivity rate at the RITM Satellite Clinic.

~12 incidence in the MSM Cohort study

MSM and HIV in PH

Personal communication with Dr. Rossana Ditangco, Head, HIV/AIDS Research Group

What city in Metro Manila has the greatest prevalence of HIV among MSM?

A. Manila

B. Quezon City

C. Mandaluyong

D. Caloocan

Question

• NCR• Region 4A (Batangas,

Cavite, Laguna, Rizal, Quezon, Tagaytay)

• Region 7 (Bohol, Cebu, Negros Oriental, Siquijor)

• Region 3 (Aurora, Bataan, Bulacan, Nueva Ecija, Pampanga, Tarlac)

• Region 11 (Compostela Valley, Davao del Norte, Davao del Sur and Davao)

MAY 2015

Prevalence rate of HIV among MSM (DOH 2015)

– Quezon City - 6.6%

– Manila - 6.7%

– Caloocan - 5.3%

– Cebu - 7.7%

– Davao - 5.0%

– Cagayan de Oro - 4.7%

http://www.rappler.com/move-ph/93344-700-hiv-cases-philippines-highest-1984

MAY 2015


Incidence no. of new cases of disease in a defined time period better in detecting outbreaks


What is the current rate of HIV diagnosis in PH?

A. 100 new cases per month

B. 10 new cases per week

C. 10 new cases per day

D. 1 new case per hour

Question

What is the current rate of HIV diagnosis in PH?

A. 100 new cases per month

B. 10 new cases per week

C. 10 new cases per day

D. 1 new case per hour

Question

INTRODUCTION TO HEALTHCARE-ASSOCIATED

INFECTIONS (HAIs)Arthur Dessi E. Roman MD MTM FPCP FPSMID

9 February 2016

gonabedess @gonnabedess

Question

Of the total SARS infections (n-=8,422), what percentage are HCWs?

A. <10%

B. 21%

C. 48%

D. 80%WHO/CDS/CSR/GAR/2003.11. Consensus document on the epidemiology of severe acute respiratory

syndrome (SARS)

Question

Of the total SARS infections (n-=8,422), what percentage are HCWs?

A. <10%

B. 21%

C. 48%

D. 80%

WHO/CDS/CSR/GAR/2003.11. Consensus document on the epidemiology of severe acute respiratory

syndrome (SARS)

OUTLINE

I. Definition of Terms

II. Overview of HAIsA. Hospital epidemiology

B. Common Sites of HAIs

C. Factors Promoting HAIs

D. HAI Rates : Local and Global

E. Cost and Burden of HAIs

III. Chain of HAIs

Epidemiology

the study of the distribution or occurrence of a disease or event in a given population or geographical area including the factors that

contributed to these

Hospital Epidemiology

the identification, understanding and development of strategies to eliminate or minimize the risk of acquiring healthcare-

associated infections by applying techniques of epidemiology

Hospital Epidemiology

“in the current era…,hospital epidemiology has expanded and

become relevant beyond the acute care hospital to all settings where

healthcare is delivered…”

Healthcare settings

• Hospitals: acute care facilities, critical access hospitals• Long term care facilities (LTCF)

Healthcare settings

• Outpatient settings

dialysis centers ambulatory surgical centers

Healthcare settings

• Outpatient settings

Physician’s offices Ambulatory chemotherapy centers

Infection

the state or condition in which the body or part of the body is invaded by a pathogenic agent (bacteria,

virus, parasites etc.) which under favorable conditions multiplies and produces injurious effects

Question

The Latin term nosocomium means:

A. Reverse or ironic

B. Hospital

C. Hands

D. Doctor

Question

The Latin term nosocomium means:

A. Reverse or ironic

B. Hospital

C. Hands

D. Doctor

Healthcare-associated Infections (HAIs)

• Previously termed hospital-acquired infection or nosocomial infection

‒“nosocomium” (latin) – hospital

‒ reflects their original association with hospitalized patients

‒ concern to separate the terminology of events from fear of liability that might have interfered with identification and control efforts [of the hospital]

Healthcare-associated Infections

• A localized or systemic condition resulting from an adverse reaction to the presence of an infectious agent(s) or its toxin(s).

• There must be no evidence that the infection was present or incubating at the time of admission to the acute care setting.

Am J Infect Control 2008;36:309-32.

Healthcare-associated Infections

• Presently the preferred term

• Infection acquired 48 hours after admission to hospital- not present or incubating at the time of admission

• Infection acquired while in the hospital and developed during admission or after discharge [up to 6 weeks]

OUTLINE


II. Overview of HAIsA. Hospital epidemiologyB. Common Sites of HAIs

C. Factors Promoting HAIsD. HAI Rates : Local and GlobalE. Cost and Burden of HAIs

III. Chain of HAIs

52

Fundamental roles of hospital epidemiology

1. Identify risks (what)2. Understand risks (how, why)3. Eliminate or minimize risks

53

Areas of interest to a hospital epidemiologist

• Surveillance for nosocomial infection• bloodstream infections

• pneumonia

• urinary tract infections

• surgical wound infections

• Patterns of transmission of nosocomial infections

• Outbreak investigation

• Isolation and other transmission-based precautions

• Evaluation of exposures

• Employee health

• Disinfection and sterilization

• Hospital engineering and environment

• water supply

• air filtration

• Reviewing policies and procedures for patient care

54

Areas of interest to a hospital epidemiologist

• Antibiotic use

• Antibiotic resistant pathogens

• Microbiology support

• National regulations on infection control

• Infection control committee

• Quantitative methods in epidemiology

• Education

• CQI strategies

OUTLINE




III. Chain of HAIs

Common Sites of HAIs

Urinary tractRespiratory tractGastrointestinalBlood streamSkin, Wound, BurnSurgical wound infection

Most common HAIs

Central Line Associated Bloodstream Infection (CLABSI)

Surgical-site Infection (SSI)

Most common HAIs

Ventilator Associated Pneumonia (VAP) Catheter-associated Urinary

Tract Infection (CAUTI)

OUTLINE




III. Chain of HAIs

Factors Promoting HAIs

• Prolonged and inappropriate use of medical devices• Extremes of age• Duration of hospitalization• Insufficient application of standard, isolation and

transmission-based precautions• Surgery (type of operation) and other medical

procedures

http://www.who.int/gpsc/country_work/burden_hcai/en/

Factors Promoting HAIs• Immune status: chemotherapy, radiation therapy, malignancy

• Understaffing

• Overcrowding

• Poor knowledge and application of basic IC measures

• Inadequate environmental hygienic conditions and waste disposal

• Poor infrastructure

• Lack of knowledge of injection and blood transfusion safety

http://www.who.int/gpsc/country_work/burden_hcai/en/

OUTLINE







III. Chain of HAIs

Healthcare-Associated Infections

Of every 100 hospitalized patients at any given time, 7 in developed and 10 in developing countries will

acquire at least one health care-associated infection.


http://www3.gehealthcare.com.co/~/media/images/product/product-categories/healthcare-

it/it%20department/hai-data-visualization.png


1-day survey

• 183 hospitals

• 11,282 patients

• 504 infections identified

in 452 (4%) patients

• 25.6% device-

associated

infections

Multi-state Point Prevalence Survey of

Healthcare-Associated Infections in the U.S.

N Engl J Med 2014;370:1198-208.


0

2

4

6

8

10

12

14

16

SHIP NHSN INICC

CA-Urinary Tract Infection

CL-Associated Bloodstream Infection

Ventilator Associated Pneumonia

Comparison of Device-Associated Infections

(per 1000 device days)

SHIP 2013 / NHSN 2006-2008 / INICC 2004-2009

SHIP – Surveillance of Hospital Acquired Infections in the Philippines

NHSN – National Healthcare Safety Network

INICC – International Nosocomial Infection Control Consortium

American Journal of Infection Control 2012; 40(5):396-407.

OUTLINE







III. Chain of HAIs

The “C ST” of HAIs

Personnel

• Need for hospitalization

• Income loss

• Pain and suffering

• Disfigurement/Disability

• Death

Institutions

• Loss of revenue

• Extra duty

• Liability insurance

• Malpractice

• Reputation

Increased resistance of microorganisms

Extra C STS by type of HAI

JAMA Intern Med. 2013;173(22):2039-2046

Extra C STS by type of HAI

17

Extra

Costs

and

Length

of Stay

of HAIs

Increased Mortality

(excess crude mortality)

CLABSI 14.7%

CAUTI 7.3%

VAP 15.3%

BURDEN OF DEVICE-ASSOCIATED INFECTIONS

Longer Hospital Stay

(extra LOS in days)

CLABSI 10.9

CAUTI 12.2

VAP 11.7

American Journal of Infection Control 2012; 40(5):396-407.

OUTLINE







III. Chain of HAIs

How do infections occur in hospital setting ?

AGENT

SUSCEPTIBLEHOST

MEANS OF TRANSMISSION

Epidemiologic Triangle

DISEASE


AGENT

SUSCEPTIBLEHOST

MEANS OF TRANSMISSION


DISEASE

AGENTS

GRAM NEGATIVE

RODS

GRAM POSITIVE

COCCI

OTHERS

Escherichia coli Staphylococcus

aureus

Fungi -

Candida sp.;

Aspergillus sp.

Klebsiella sp. Staphylococcus

epidermidis

Protozoans

Pseudomonas

aeruginosa

Enterococci Mycobacterium

tuberculosis

Acinetobacter sp. Pneumocystis

carinii

Enterobacter sp. Anaerobes

Sources of Agents of Nosocomial Infections

EXOGENOUS

• Hands

• Instruments

• Catheters

• Respiratory equipments

• Transfusions

• IV system

• Linen

• Air

ENDOGENOUS

• Oropharynx

• Respiratory

• Gastrointestinal

• Skin


AGENT

SUSCEPTIBLEHOST


DISEASEMEANS OF

TRANSMISSION

Means of Transmission of HAIs

CONTACT

AIRBORNE

DROPLET

VECTOR

VEHICLE

- direct or indirect

- measles, varicella, TB

- meningococcemia

- insects or animals

- food, water, blood,

medication


CONTACT- most common means of transmitting microorganisms from one person to another

CONTACTA. Direct Contact

- occurs when one person touches another

- direct contact is an ongoing process in the hospital

- best vehicle : Hands


CONTACTB. Indirect Contact

- occurs when a person touches an inanimate object contaminated by an infected patient


Question

According to WHO, what percentage of HAIs are caused by poor hand hygiene?

A. <1%

B. 20%

C. 40%

D. 75%

Question

According to WHO, what percentage of HAIs are caused by poor hand hygiene?

A. <1%

B. 20%

C. 40%

D. 75%


AGENT


DISEASEMEANS OF

TRANSMISSIONSUSCEPTIBLE

HOST

Factors that Increase Host Susceptibility to HAIs

• Chronic underlying diseases

• Immune deficiency states• Malignancies• Therapeutic measures• Immunosuppression• Antibiotic therapy

• Invasive devices

• Surgery

• Age

AGENTMeans of

Transmission

Susceptible

HostBacteria

Virus

Fungi

CONTACT

AIRBORNE

DROPLET

VEHICLE

VECTOR

Disease

AGENT

Susceptible

HOST

Means of

Transmission

The

CHAIN of

INFECTION

Break the chainof Infection

Susceptible

HOST

Breaking the

Chain of Infection

AGENT

Breaking the Chain of Infection: AGENT

The hands should be washed after handling infectious materials (e.g. bed linen, dressings, secretion and excretions).

The skin of the patient should be disinfected before invasive procedures

Emphasize HAND WASHING for personal hygiene


Rational Use of Devices

-avoiding or removing factors that impair host defenses.

- invasive devices should be avoided or should be removed as soon as possible.


Susceptible

HOST

Breaking the

Chain of Infection

Means of

TransmissionAGENT

Isolation techniques based on method of spread

Breaking the Chain of Infection

Protective or Reverse Isolation Rationale: decreasing the contact

of the immunocompromised host to potential pathogens



The environment should be HOSTILE to the multiplication of pathogens i.e. clean, dry, exposed to light and well ventilated


All infectious materials (e.g. linen, clinical waste, sharps) should be safely contained, decontaminated or destroyed


Use of disposable supplies and equipment in an attempt to limit the spread of infection by this means


All instruments and equipments should be clean and dry. Invasive items should be sterilized and items in contact with mucous membranes, body fluids and potentially infectious materials should be disinfected


Food should be hygienically prepared, properly cooked and stored at low temperatures until used


Control of insect and rodents that serve as vectors in the spread of microorganisms

AGENT

Susceptible

HOST

Breaking the

Chain of Infection

Means of

Transmission


Susceptible patients or sites should be protected from pathogenic microorganisms: i.e. aseptic technique practice during wound dressing, or

procedures

Immunotherapy, immunizations and other methods of reconstituting patients’ immune response maybe attempted


Susceptible

HOST

Means of

Transmission

Hand Hygiene

Environmental Care

Waste management

Disinfection and Sterilization

Hand Hygiene

Rational use of Devices

Isolation

Breaking the

Chain of Infection

Hand Hygiene

Vaccination

Environmental Care

Prophylaxis

AGENT

OUTLINE


II. Overview of HAIsA. Hospital epidemiologyB. Common Sites of HAIsC. Factors Promoting HAIsD. HAI Rates : Local and GlobalE. Cost and Burden of HAIs

III. Chain of HAIs

The Health Care Worker (HCW) should be aware of how infection is transmitted and the factors involved in the process

The HCW should be able to implement the MOST effective and applicable measures to prevent and control infection in his place of work

The HCW should have the proper attitude towards infection prevention and control.

INFECTION CONTROL is…

BUT…

is not too common.

Infection Control should be..... a WAY of LIFE

Thank you!

Intro to Infectious Diseases and Epidemiology of Nosocomial Infection

Healthcare

Transcript of Intro to Infectious Diseases and Epidemiology of Nosocomial Infection