Preventive epidemiological
measures;
principles of vaccination
MUDr. Marie Kolářová,CSc.
Ústav ochrany a podpory zdraví LF MU
Spring 2018
Epidemiology
is the study (scientific, systematic, data-driven)
of the distribution (frequency, pattern)
and determinants (causes, risk factors)
of health-related states or events (not just diseases)
in specified populations (patient is community,
individuals viewed collectively),
and the application (since epidemiology is a discipline
within public health)of this study to the control of health
problems.
SURVEILLANCE
The systematic
 collection,
 analysis,
 interpretation, and
 dissemination of health data on an ongoing basis,
to gain knowledge of the pattern of disease
occurrence and potential in a community,
in order to control and prevent disease in the
community.
WHO Health
statistics
and information
system
The World Health Organization (WHO) is a specialized
agency of the United Nations that is concerned with
international public health.
It was established on 7 April 1948 headquartered in
Geneva, Switzerland.
The WHO is a member of the United Nations
Development Group. Its predecessor, the Health
Organization, was an agency of the League of Nations.
WHO Health
statistics
and information
system
 National Health Interview
Survey(https://www.cdc.gov/nchs/nhis/index.htm)
 Selected Data Items:
 Health status and limitations
 Utilization of health care
 Health insurance
 Access to care
 Selected health conditions
 Poisonings and injuries
 Health behaviors
 Functioning/disability
 Immunizations

 Diseases preventable by vaccination
 Sexually transmitted diseases
 Viral hepatitis
 Food- and waterborne diseases and diseases of
environmental origin
 Diseases transmitted by non-conventional agents
(prions)
 Airborne diseases
 Zoonoses (other than those listed above)
 Serious imported diseases
 Vector-borne diseases
 Special health issues (HAI, antibiotic resistence)
Diseases and
special health
issues under
EU surveillance
European
Tuberculosis
Surveillance Network
The European Tuberculosis Surveillance Network consists
of TB surveillance experts from all 53 countries belonging to
the World Health Organization’s European Region, including
30 EU/EEA Member States.
Under the joint coordination of ECDC and the World Health
Organization’s Regional Office for Europe, the network
collects, validates, analyses and disseminates European TB
surveillance data.
The purpose of the network is to identify the epidemiological
patterns of TB in the Region and monitor progress towards
TB elimination, with key surveillance and monitoring findings
published in an annual report.
In addition, the network aims to further strengthen TB
surveillance in Europe.
SURVEILLANCE
Surveillance programmes can be carried out on a large
scale such as for districts and regions.
In the Czech Republic, surveillance programmes exist
for poliomyelitis, pertussis, diphtheria, measles, viral
hepatitis, alimentary infections and influenza.
Under the general guidelines released by WHO,
surveillance of influenza is carried out on an
international level.
 BENCKO, Vladimir, et al. Hygiene and Epidemiology : Selected Chapters. 2nd edition. Prague. 2008. ISBN 80-246-0793-X.
Vybrané infekční nemoci v ČR v letech 2006 – 2016; absolutně
0
10000
20000
30000
40000
50000
60000
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
Varicella
Campylobacteriosis
Salmonellosis
Virové průjmy
Vybrané infekční nemoci v ČR v letech 2006 – 2016; absolutně
0
200
400
600
800
1000
1200
1400
1600
1800
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
VHC
Akutní VHB
VHA
VHE
2.4.2018
2.4.2018
2.4.2018
17
Solving
health
problem
Step 1
Date collection
Step 2 Assessment
Step 3
Hypothesis testing
Step 4
Action
Surveillance; determine
time, place and person
Inference
Determine how and why
Intervention
Eradication and
Elimination
Eradication is an absolute process, an “all or
none” phenomenon, restricted to termination of
infection from the whole world.
Smallpox eradication was officially
announced at the 33rd General Assembly
WHO
8. May 1980.
 The term elimination is sometimes used to
describe eradication of a disease from a large
geographic region. Disease which are amenable
to elimination in the meantime are polio,
measles and diphtheria.
Global Disease
Elimination and
eradication
 During the 25 years since the certification of smallpox eradication
there has been considerable debate among public health
practitioners about how existing health technologies can best be used
to decrease infectious disease incidence and prevalence.
 Interruption of transmission has often been envisaged as the ultimate
goal, and standard public health concepts of disease reduction have
been defined or re-defined.
 In 1998, Dowdle proposed a definition of control as a reduction in the
incidence, prevalence, morbidity or mortality of an infectious disease
to a locally acceptable level;
 elimination as reduction to zero of the incidence of disease or
infection in a defined geographical area;
 and eradication as permanent reduction to zero of the worldwide
incidence of infection
Health 2020:
the European
policy for health
and well-being
Health 2020 is the new European health
policy framework.
It aims to support action across government
and society to:
“significantly improve the health and wellbeing
of populations,
reduce health inequalities,
strengthen public health and ensure peoplecentred
health systems that are universal,
equitable, sustainable and of high quality
Chain of infections
(epidemic proces)
THE CAUSATIVE AGENT OF INFECTION (bacteria, viruses, fungi, prions, protozoa)
1. the presence of rezervoir (source) of infection
man, animal at the ende of incubation period
acute stage
cariers
2. the way of transmission A/ direct contact
touching, kissing or sexual intercourse (Staphylococcus spp., Gonococcus spp.,HIV …),
- vertical transmission – from mother to fetus (VHB, VHC, HIV, listeria, rubella,
cytomegalovirus…)
B/ indirect contact
- inhalation of droplets containing the infectious agents (TBC, measles, influenza…)
- ingestion of food or water that is contaminated (salmonella, Norwalk virus, VHA….)
- biological transmission by insects (malaria, borellia….)
3. the susceptibility of the population or its individual members to the organism concerned
Host factors : a g e , n u t r i t i o n, g e n e t i c s
i m m u n i t y – natural (nonspecific),
- acquired
THE INFECTION
= 1. source of infection
……….
Chain of infections
(epidemic proces)
If the epidemiology is know, we can interfere with
transmission:
„BREAKING THE CHAIN OF INFECTION“
Different infections have different epidemiologies and
thus require different methods of control
Preventive anti-
epidemic
measures
is a set of measures to prevent the infection of
susceptible individuals:
primary , when we prevent impact of external risk
factors , or we will increase the resistance of the
individual (epidemiology)
Secondary prevention is early to find (diagnosis),
treatment and prevention of further development
of the disease and complications (clinical
medicine)
Tertiary prevention monitors patients who have
overcome the disease
Preventive anti-
epidemic
measures
 Include:
Increasing hygienic standards of the population - the most important is
compliance with sanitary regulations relating to water supply , food ,
manufacturing and food handling , waste water , waste , faeces and so
forth.
Vaccination - in order to induce maximum collective immunity.
Evidence and vector control (and the people with them living in the same
household) - on the territory concerned health authorities must register for
(eg. Portability typphoid, salmonella, bacillary dysentery and diphtheria);
must be under constant medical supervision , regular microbiologically
examined or treated . Must submit certain restrictive measures , always
report a change of residence must not endanger their actions of another
person .
Measures to prevent the introduction of infection into collectives entrance
examinations (to work, camp, army, morning filters in nurseries
and kindergartens), prevent the entry into the collective persons that could
be a source of infection (important information too).
Preventive anti-
epidemic
measures
Prophylactic desinfection - aims to reduce the number of pathogens in
the external environment (public buildings, medical facilities, public
transport, drinking water, waste water from hospitals, milk pasteurisation).
Border protection - a system of measures protecting the borders of the
introduction of diseases from foreign persons , materials , goods,
imported animals . It is, among other things. Persons who come from
countries with endemic or epidemic occurrence of serious communicable
diseases . Such passengers must show a valid vaccination certificate, if
you do not or are not vaccinated, subjected to medical supervision,
quarantine or vaccination. Quarantine diseases as plaque, yellow fever
and cholera. As for the people, not absolute boundaries conserve data.
More important is the protection of imported commodities , which must
be accompanied by a certificate of health or veterinary authorities about
their health .
Health education - raising awareness of health and culture of the
inclusion of basic hygiene and epidemiology in school and extracurricular
educational facilities.
Herd immunity
(also called herd effect,
population immunity, or
social immunity)
is a form of indirect protection from infectious disease
that occurs when a large percentage of a population
has become immune to an infection, thereby providing
a measure of protection for individuals who are not
immune.
In a population in which a large number of individuals are
immune, chains of infection are likely to be disrupted,
which stops or slows the spread of disease.
The greater the proportion of individuals in a community
who are immune, the smaller the probability that those
who are not immune will come into contact with an
infectious individual.
Individual immunity
can be gained through recovering from a natural
infection or through artificial means such as
vaccination.
Some individuals cannot become immune due to
medical reasons and in this group herd immunity
is an important method of protection.
Herd immunity
(also called herd
effect,
population immunity,
or social immunity)
Once a certain threshold has been reached, herd immunity
gradually eliminates a disease from a population.
This elimination, if achieved worldwide, may result in the
permanent reduction in the number of infections to zero, called
eradication.
This method was used for the eradication of smallpox in 1977
and for the regional elimination of other diseases] Herd
immunity does not apply to all diseases, just those that are
contagious meaning that they can be transmitted from one
individual to another.] Tetanus, for example, is infectious but not
contagious, so herd immunity does not apply].