emerging and re-emerging infectious diseases introduction responsible factors classification...

Emerging andRe-emerging Infectious Diseases

INTRODUCTIONRESPONSIBLE FACTORSCLASSIFICATIONDISEASES OF CONCERNPREVENTION

INTRODUCTION :INFECTIOUS DISEASESINFECTIOUS DISEASES

Accounted for about 26% of the 57 million deaths worldwide in 2002.

Remain among leading causes of death worldwide despite remarkable advances in medical research and treatments.

In addition, nearly 30% of all disability adjusted life years (DALYs) could be accounted to infectious diseases.

Emergence of new infectious diseases, re-emergence of old infectious diseases and persistence of intractable infectious diseases, all led to persistence and even increase in infectious diseases in many parts of the world .

DEFINITIONSEmerging Infectious DiseasesEmerging Infectious Diseases

It includes outbreaks of previously unknown diseases or known diseases whose incidence in humans has significantly increased in the past two decades.

Re-emerging Infectious DiseasesRe-emerging Infectious Diseases

These are the known diseases that have reappeared after a significant decline in incidence.

““Are infectious Are infectious diseases emerging more diseases emerging more recently than before?recently than before? “ “

Major Factors Contributing to Emerging Infections: 1992

1) Human demographics and behavior

2) Technology and Industry

3) Economic development and land use

4) International travel and commerce

5) Microbial adaptation and change

6) Breakdown of public health measures

More Factors Contributing to Emerging Infections: 2003

1) Human vulnerability2) Climate and weather3) Changing ecosystems4) Poverty and social inequality5) War and famine6) Lack of political will7) Intent to harm

Emerging Infections:Human Demographics, Behavior, Vulnerability

More people, more crowding.

Changing sexual mores (HIV, STDs)

Injection drug use (HIV, Hepatitis C)

Changing eating habits: out more, more produce (food-borne infections)

More populations with weakened immune system: elderly, HIV/AIDS, cancer patients and survivors, persons taking antibiotics and other drugs.

Emerging Infections:Technology and Industry

Mass food production (Campylobacter, E.coli O157:H7, etc…)

Use of antibiotics in food animals (antibiotic-resistant bacteria)

More organ transplants and blood transfusions (Hepatitis C, WNV,…)

New drugs for humans (prolonging immunosuppression)

A big city on a sunny day

Emerging Infections:Economic Development, Land Use, Changing Ecosystems

Changing ecology influencing waterborne, vector borne disease transmission (e.g. dams, deforestation)

Contamination of watershed areas by cattle (Cryptosporidium)

More exposure to wild animals and vectors (Lyme disease, erhlichiosis, babesiosis, …)

Emerging Infections:

International Travel and Commerce Persons infected with an exotic

disease anywhere in the world can be into your city within hours (SARS)

Foods from other countries imported routinely into your city (Cyclospora,….)

Vectors hitch-hiking on imported products (Asian tiger mosquitoes on bamboos….)

Emerging Infections:

Microbial Adaptation and Change

Increased antibiotic resistance with increased use of antibiotics in humans and animals (VRE, VRSA, penicillin- and macrolide-resistant Strep pneumoniae, multidrug-resistant Salmonella,….)

Increase virulence (Group A Strep)

Jumping species from animals to humans (avian influenza, HIV?, SARS?)

Emerging Infections:Poverty, Social Inequality, Breakdown of Public Health Measures

Lack of basic hygienic infrastructure (safe water, safe foods, etc..)

Inadequate vaccinations (measles, diphtheria)

Discontinued mosquito control efforts (dengue, malaria)

Lack of monitoring and reporting (SARS)

Emerging Infections:

Intent to HarmBioterrorism: Anthrax in

US 2001Bio-Crimes: Salmonella ,

Shigella Potential agents:

Smallpox, Botulism toxin, Plague, Tularemia, ….

LIST OF EMERGING & RE-EMERGING DISEASES

GROUP-1PATHOGENS NEWLY RECOGNIZED IN LAST

TWO DECADES

ACANTHAMOEBIASISBABESIOSISBARTONELLA HENSELEEHERLICHIOSISCORONA VIRUS(SARS)

CONTD…H.PYLORIHEPATITIS CHEPATITIS EHUMAN HERPES VIRUS8(HHV8)HHV6LYMEBORRELIOSISPARVO VIRUS B19

GROUP-2

REMERGING PATHOGENS

ENTEROVIRUS71CLOSTRIDIUM DEFFICILECOCCIDIOIDES IMMITISMUMPS VIRUSPRIONSTREPTOCOCCUS GROUP ASTAPHYLOCOCCUS AUREUS

GROUP-3

AGENTS WITH BIOTERRORISM POTENTIAL

CATEGORY AB.anthracisC.botulinumY.pestisV.majorF.tulariensisHanta virus

CATEGORY B

B.malleiB.pseudomalleiC.brunettiBrucellaRicin toxinEpsilon toxin(c.perfringens)EnterotoxinB(staphylococcus)Viral encephalitides(Japanese encephalitis

virus,kyasanur forest virus)

CONTD…

FOOD &WATER BORNE DISEASES

BACTERIA(E.coli,Vibrio,shigella)VIRUS(Hepatitis A,Calcivirus)PROTOZOANS(Giardia,Entamoeba,Cryptospori

dium)

CATEGORY C

TICK BORN HAEMORRHAGIC FEVERSTICK BORN ENCEPHALITIC FEVERYELLOW FEVERMDR TB & XDR TB RABIESSARS ASSOCIATED CORONAVIRUSANTIMICROBIAL RESISTANCE

IMPORTANT RE-EMERGING DISEASESTUBERCULOSISDENGUE FEVERMALARIAMENINGOCOCCAL MENINGITISBUBONIC PLAGUEHANTA VIRUS PULMONARY SYNDROME

HIV/AIDSPresent situation and challenges

HIV epidemic in SEAR mainly due to: Unsafe sex Injecting drug use Poverty Low literacy Widespread stigma Weak health systems.

India, Thailand, Myanmar, Indonesia and Nepal – account for the majority of the burden in the Region.

SARS A patient was admitted in Vietnam on 26th Feb. 2003 with respiratory illness and died in March 2003.

7 health workers who cared for this patient also became ill on 5th March 2003.

Since then, the cases have been reported from many countries.

International travel facilitated its spread rapidly.

It was found that the disease initially emerged in China in November 2002.

The etiological agent is a virus -- isolated, but yet to be identified. Perhaps, it is a mutated strain of corona virus or a virus, which has jumped from an animal species to humans.

The infection is spread through droplets/aerosols. (It is also possible that SARS is transmitting through other unidentified routes.)

AVIAN INFLUENZAAVIAN INFLUENZAREASONS FOR CONCERN ABOUT THE CURRENT OUTBREAKS

•Most outbreaks caused by the highly pathogenic H5N1 strain.•Strain has unique capacity to jump the species barrier & cause severe disease, with high mortality, in humans.

•Gene swapping between the human & viruses inside the human body can give rise to a comavian pletely new subtype of the influenza virus to which Very few, if any, humans would have natural immunity.

•Sufficient human genes in virus direct man to man transmission Pandemic.

• influenza pandemic of 1918–1919 when the virus spread around the globe in 4-6 months.

•existing vaccines, would not be effective against completely new influenza virus.

TuberculosisPresent situation

SEAR with 5million cases, has the highest number of TB cases among all WHO regions.

Bangladesh, India, Indonesia, Myanmar and Thailand are among the 22 high-burden countries in the world and together account for 95% of the TB burden in the Region.

TB -most common opportunistic infection among HIV-infected.

~3 million people co-infected with HIV & TB.

Every year 3 million people newly

affected. over 500000 lose their lives.

TB has emerged as MDR-TB & XDR-TBAbout 50 million people worldwide are infected with

drug resistant TB% of MDR-TB in INDIA in 2004 was 2.4 among new

casesSTOP TB STRATEGY adopted by WHO in 2006

focusses on prevention & control of MDR-TB & HIV -TB

MalariaPresent situation and challenges

PAST TWO DECADES

The proportion of Plasmodium falciparum malaria has increased from 12% to more than 45%.

Increasing resistance of Plasmodium falciparum to first- and second line anti- malarial drugs.

MalariaPresent situation and challenges

India reports the largest proportion of malaria cases in the Region.

Annually there are approximately 100 million cases in SEAR

PRESENTLY

About 2.5 million cases and 4000 deaths per year.

DENGUEPresent situation and challenges

Dengue has emerged as a serious public health problem over the last few decades.

Disease is spreading to new geographical areas, and frequency of outbreaks has increased.

During 2007, outbreaks have been reported from a number of countries in Asia including Thailand, Cambodia, Indonesia, Vietnam, Philippines and even in Singapore, which has one of the best dengue control programmes.

State wise dengue cases and deaths, India, 1998-2001

States 1998 1999 2000 2001

Cases Deaths Cases Deaths Cases Deaths Cases Deaths

Andhra Pradesh --- --- --- --- 05 Nil 0 0

Delhi 333 05 168 02 180 02 0 0

Goa 0 0 0 0 0 0 1 0

Gujarat Nil 0 92 0 29 0 0 0

Haryana 14 0 03 0 2 0 0 0

Karnataka 115 03 39 0 168 0 45 0

Kerala 0 0 0 0 0 0 0 0

Maharashtra 199 05 59 12 66 03 05 0

Orissa 11 0 0 0 0 0 0 0

Punjab 0 0 419 01 91 01 0 0

Rajasthan 02 0 01 0 0 0 0 0

Tamilnadu 33 05 135 02 81 01 06 0

Uttar Pradesh 0 0 28 0 0 0 0 0

Total 707 18 944 17 622 07 57 0

PLAGUEIn SEAR, natural foci of plague- exist in INDIA,

INDONESIA , MAYANMAR & NEPALNo case was reported after 1966 in INDIA till it re-

emerged in sept 2004 in MAHARASHTRA1997- outbreak of pneumonic plague in SURAT2002- 16 cases of pneumonic plague(4 deaths) in hatkoti ,

distt SHIMLA

SCRUB TYPHUS

• During world war II, an epidemic of scrub typhus occurred in ASSAM & WEST BENGAL.

• 1970 -80,it was reported from INDIA, CHINA, JAPAN, INDONESIA & MALAYSIA.

• In july,2008 ,outbreak occurred in some areas of HP.

Response To Response To “Threat”“Threat” Various international & national organizations

have come together to combat this threat.

WHO, CDC, NIH, Department of Defense & FDA.

ALL work in collaboration to develop strategic plans to combat the microbial emergence and re-emergence.

Surveillance and Response

Applied Research

Infrastructure and Training

Prevention and Control

Surveillance Global / Regional level laboratory surveillance

FLUNET : Surveillance network for monitoring influenza\ RABNET : Surveillance network for rabies

PANCET : Pacific Public Health Services Network - to improve surveillance in pacific island.

Surveillance

GPHIN : Global Public Intelligence Network

Antimicrobial resistance information bank Global / Regional level epidemiological surveillance.

International Health Regulations (IHR) mandatory reporting of certain infectious diseases eg. Cholera, plague, yellow fever

WHO Disease / rumor outbreak list - list unconfirmed disease outbreaks worldwide.

Global & National Surveillance Systems / Networks

At National Level - strong surveillance system is required to collect relevant, accurate & timely information of an outbreak.

WHO – at Global Level- act as focal point for data exchange. WHO has recommended surveillance standards for 40 specific diseases and 8 syndromes.

HIV/AIDS network – through sentinel sites Influenza network- Collects information from member laboratories to make

decision regarding vaccine composition .

Tuberculosis monitoring system- Produces reports on notification, results and the extent of implementation of DOTS .

Global salmonella surveillance network .

Research: Various organizations like CDC, National Institute

of Allergy & Infectious Diseases (NIAID), National Institute of Diabetes Digestive and Kidney diseases (NIDDK), has made research contributions in field of HIV/AIDS, Tuberculosis, Malaria, Hepatitis C etc.

Advances in genomics, proteomics better understanding of pathogenesis, host immunity & drug resistance and identifying new drug targets & develop new vaccines and diagnostics.

• Strengthen public health infrastructures to support surveillance, response, and research.

• To implement prevention and control programs.

• Provide the public health work force with the knowledge and tools it needs.

Prevention and ControlGlobal outbreak Global outbreak

ResponseResponse:: It involves- building a

team, obtaining access and travelling to affected area, recommending and implementing control measures.

NATIONAL LEVELNATIONAL LEVEL District epidemic management

committee:-For resource mobilization, monitoring and evaluation of control activities; dissemination of information to public & documentation of outbreak.

District rapid response team:- For investigation of outbreak and implementation of control activities at the district level.

The Health facility personnel:- For case management, reporting and education of public.

Community Leaders: Helping in controlling the epidemic.

FETP (Field Epidemic Training ProgrammeFETP (Field Epidemic Training Programme)

PHSWOW ProgrammePHSWOW Programme (Public Health Schools without walls)- Two year field and academic training programme, established by CDC in collaboration with Rockefeller foundation.

TEPHINET :TEPHINET : Training programme in epidemiology

Epi – Aid :Epi – Aid : For rapid deployment of professional staff to aid outbreak verification & control.

Future Outlook :MAJOR GOAL: -development and production of counter measures. -requires basic research and concept development.Application and research in molecular biology. To develop a second- generation of vaccines (safe and

effective) e.g. 1.‘naked DNA' vaccine 2. recombinant proteins to fight against HIV/AIDS, malaria and tuberculosis Sequencing the genomes develop effective vaccines

and drugs. Other developments next-generation anthrax vaccine,

Ebola vaccine and monoclonal antibodies against botulism toxin

Partnerships among clinicians, researchers, government and industry.

Improving#surveillance, #disease control# response to an outbreak

through improved laboratory facilities

# training of personnel# establishing reliable and efficient

communication networks # strong public health

GUIDED BY:-

DR. ANUPAM PARASHAR

PRESENTED BY:Nandini sood(0537)Neha chauhan(0538)Nitin Sood(0539)Nishant sharma(0540)Nripen Gaur(0541)Priyanka Sood(0542)

THANKS