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Morbidity of the population.
Sources and methods of its
studying
Morbidity is one of the major criteria
characterizing health of the population. The
morbidity is an indicator characterizing prevalence,
structure and dynamics of the registered illnesses
among the population in whole or in its separate
groups (age, sex, territorial, professional, etc.) and
serving one of the criteria of work assessment of a
doctor, medical institution, public health services
unit.
AS THE OBJECT OF SCIENTIFIC RESEARCH AND
PRACTICAL ACTIVITIES OF PUBLIC HEALTH
SERVICES
ESTABLISHMENTS
MORBIDITY
REPRESENTS A COMPLEX SYSTEM OF RELATIVE
CONCEPTS:
Morbidity represents a complex
system of relative concepts:



Incidence (primary disease incidence) – frequency of
the new, nowhere recorded before and revealed for the
first time in the given calendar year, diseases among the
population;
prevalence
(morbidity,
accumulated
disease
prevalence) – frequency of all diseases existing among
the population, both revealed for the first time in the
given calendar year, and registered in previous years
because of which the patient has appealed for medical
aid in the given year again;
incidence of the diseases revealed at medical
inspection (pathological affection, point prevalence) –
frequency of pathology among the population,
determined at carrying out of single medical inspections
(examinations); as a result, all the diseases are
considered, as well as premorbide forms and conditions.
Disease of the population is studied by three
essentially various methods:
by data of population appealability for medical aid,
 according to medical inspections,
 by data of death causes.
By appealability data one can study acute morbidity
better as in the structure of appeals for medical aid
acute forms of pathology (to 60-70 %) prevail and only
the third part of patients appeals to medical institutions
because of chronic diseases.
Medical inspections are organized for chronic
diseases unknown for doctors and medical institutions.
The analysis of death causes gives insight about the
most severe forms of the death causing diseases.

In morbidity statistics it is used
to single out:
the general disease incidence (by data of
appealability, according to medical inspections,
under the analysis of death causes),
 infectious morbidity,
 morbidity with the main nonepidemic illnesses,
 the hospitalized morbidity,
 morbidity with temporal disability.
The WHO specifies, that whatever morbidity
index is calculated, it should correspond to a
number of requirements: to be reliable,
objective, sensitive, exact.

The general morbidity according
to appealability data
The account of all cases of diseases, with which
the population has appealed for medical aid, is
conducted in all medical institutions. At studying
of the general morbidity by appealability data for
a registration unit is accepted the first appealing
to the doctor on occasion of the given disease
within a calendar year. Diagnoses of acute
diseases are registered at their every new
occurrence, chronic diseases are considered only
once a year, exacerbations of chronic diseases
this calendar year are not re-registered as
diseases.
At the morbidity analysis it is used to count a
number of indices:
 Primary
disease incidence
 The
general disease incidence by
appealability
 Morbidity
structure
.
Dynamics of population morbidity in the Russian
Federation by appealability data (‰)
Year
1995
1999
2002
2005
2008
Children
1486,3
1724,7
1893,5
1990,5
2336,4
Teenagers
1143,5
1462,8
1575,8
1600,5
1825,3
Adults
1053,5
1141,4
1227,1
1245,7
1401,3
The morbidity analysis by appealability data shows,
that its level is substantially defined by age of patients.
Morbidity level at children is the highest, then morbidity
by appealability data decreases and reaches the lowest
level at adult population.
Structure of the general morbidity by appealability
data of adult and children population of the Russian
Federation
Children population
Adult population





Respiratory diseases –
19 %
Blood circulation
diseases – 15 %
Diseases of
musculoskeletal system
–9%
Diseases of digestive
apparatus – 8 %
Other classes of
diseases – 49 %





Respiratory diseases –
40 %
Diseases of digestive
apparatus – 8 %
Infectious and parasitic
diseases – 6 %
Diseases of
musculoskeletal system
–5%
Other diseases – 40 %
In morbidity structure, both at children, and at teenagers
and adults respiratory diseases prevail, however at
children they occur several times more often, than at
adults.
Structure of morbidity



Respiratory diseases are presented mainly by acute forms of
diseases: acute viral respiratory infections and flu, acute
tonsillitis –it takes to 90 % of all cases of appeals. Rather
insignificant part in the structure falls to a share of chronic
diseases of this class: chronic pneumonia – 3 %, bronchial
asthma – 1 %, and so on.
The second place in the structure of adult population
morbidity is occupied by blood circulation diseases; first of all,
it is ischemic disease of the heart – 33,5 %, cerebrovascular
diseases – 21,9 %, essential hypertension – 17.8 %. On the
third place in the structure of adult population morbidity there
are diseases of musculoskeletal system and connective
tissue diseases.
In the structure of children morbidity the second place is
occupied by diseases of digestive apparatus, and in the third
place there are infectious and parasitic diseases.
Iceberg of disease
The quantity of the diseases
revealed in a course of What the
appealability of the population
for medical aid is great, but it is physician
considerably below the true sees
number of diseases, which the
population suffered within a
year. Disease can be compared
Symptomatic
to an iceberg which surface part
disease
are illnesses that make the
population appeal to medical
institutions, and underwater part
is formed by those who remain
Preunknown for medical workers.
symptomatic
Therefore, for more complete
estimation of public health by
disease
appealability data it is necessary
to supplement indices with the
data received as a result of What the physician does not
sees
medical examinations.
Depending on tasks in view and used
organizational technologies medical inspections
subdivide to:

Preliminary medical examinations;
 Periodic medical examinations;
 Target medical examinations.
Preliminary medical examinations are carried out
at employment or study for the purpose of
definition of conformity of a state of health to
trade or training requirements, and also revealing
diseases, which can progress in conditions of
working with occupational hazards or during the
course of study.
Another technologies of medical
inspections
Target medical examinations are carried out, as
a rule, for revealing of early forms of sociallysignificant diseases (malignant new growths, a
tuberculosis, a diabetes, etc.) and cover
various groups of the organized and
unorganized population.
 In the best way of carrying out of mass medical
inspection, from the point of view of its quality,
is its performance by brigade of experts.
However, such examinations are connected
with necessity of attraction of considerable
personnel, financial, and material resources.

Organizational forms of medical examinations


Therefore the aspiration to cover the most possible part of the
population by medical examinations with attraction of the
limited volume of resources has caused working out and
introduction of various organizational forms of inspection with
use of various tests. These organizational forms bear the
general name of "screening". The concept "screening"
originates from an English word "screening" that means
sifting, elimination, selection.
Screening is a mass inspection of the population and
detection of persons with diseases or with initial signs of
diseases. The screening main objective is to carry out
primary selection of the persons demanding profound
inspection, consultation of specialists, formations of higher
risk groups with diseases of certain pathology. As a rule,
target (screening) medical examinations are carried out in
some stages.
Indicator of pathological involvement

As a result of medical examinations, there were revealed
additional cases of diseases on occasion of which there
were no appeals to the public health services organization
within a year. The indicator of pathological involvement is
calculated at that:

At well planned and carried out medical examinations 20002500 cases of diseases (per 1000 population), which were
not the reason of patients’ reference to medical institutions
additionally come to light. Besides, to obtain a full and
objective picture of population morbidity cases of diseases,
which have led to the patient’s death, but were not the
reason
of
his
appealing
to
medical-diagnostic
establishments during lifetime should be registered as well.
These cases are registered at postmortem study and
forensic medical examination.
Infectious morbidity
The State Sanitary and Epidemiological Supervision Authority
should be necessarily notified of each case of the revealed
infectious disease. Infectious diseases are subject to the
special account on all territory of Russia irrespective of a
place of infection and citizenship of the patient. The list of
obligatory infectious diseases for the notice is defined by the
Ministry of Health Service of the Russian Federation. All
infectious diseases subjected to the notification can be divided
into following groups:
1. quarantine diseases is a conditional name of the infectious
diseases group characterized by high contagiousness and high
lethality to which the international quarantine restrictions
according to the international medical and sanitary rules are
applied. The plague, cholera, natural smallpox, yellow fever are
considered quarantine diseases. About all cases of these
diseases or suspicions to them the extraordinary report goes to
public health services higher authorities when due hereunder;

Groups of infectious disease which are registered by the State
Sanitary and Epidemiological Supervision Authority
2. Diseases, each case of which is messaged to local authorities
of the State sanitary and epidemiological supervision with
detailed information about disease (belly typhus, paratyphus
and other salmonelloses, dysentery, enterites, children's
infections, meningitis, encephalites, infectious hepatitis,
tetanus, poliomyelitis, hydrophobia, ricketsioses, malaria,
leptospirosis, sepsis at children of the first month of life,
hemorrhagic fevers, ornithosis, etc.);
3. diseases as the most socially significant illnesses with the
simultaneous information of the State Sanitary and
Epidemiological Supervision Authority; the information about
these diseases is collected by the system of specialized
curative and prophylactic establishments (tuberculosis, syphilis,
gonorrhea, trachoma, mycoses, lepra, etc.);
4. diseases, about which the curative and prophylactic
establishment gives only the total (digital) information to the
State Sanitary and Epidemiological Supervision Authorities and
which do not belong by classification to the class of infectious
diseases (a flu, acute respiratory viral infection (ARVI).
The rules of registration
The medical worker who made the diagnosis or
has suspected an infectious disease, is obliged
within 12 hours to make "The Emergency notice
about an infectious disease, food, acute,
professional poisoning, unusual reaction to an
inoculation" and to direct it to the territorial centre
of the State sanitary and epidemiological
supervision.
 The state system of the statistical account of
infectious diseases is necessary for carrying out
against epidemic actions: the observation,
revealing of contacts and infection sources,
disinfection, vaccination and so on, and also gives
the chance to receive the fullest representation
about prevalence of infectious diseases in country
territory.

Level of epidemic morbidity at Stavropol Territory
per 10 thousand population
Registered diseases
Adults
Children
Infectious and parasitic diseases
totall
1684,8
7132,6
Including those without ARD and flu
128,9
495,9
Acute intestinal infections
51,5
207,9
Including dysentery
3,8
12,5
Salmonellosis
2,6
6,2
Virus hepatitis
2,1
2,2
Chronic virus hepatitis
4,7
0,4
Chicken pox
36,3
205,9
Rubella
9,9
39,3
Measles morbidity in dynamics (per 100000
population)
Россия
Ставропольский край
250
200
150
100
50
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
0
1981
Many infectious
diseases
have
wavy character of
the
course,
therefore specific
preventive
maintenance
(vaccination) it is
necessary
to
carry out, even
though
the
disease is at a
low level for a
number of years.
1980

300
Non-epidemic diseases
Alongside with the obligatory registering of
infectious disease the special registration of
the major non-epidemic diseases, to which
tuberculosis, venereal diseases, mycoses,
trachoma, etc belong. Some of them are
considered both as infectious diseases, and as
the major non-epidemic illnesses. The
organization of the special registration of some
diseases is connected by the fact, as a rule,
that they demand early revealing, total
examination of patients, their dispensary
registration, constant supervision over them
and special treatment, and in some cases –
revealing of contacts as well.