Introduction to Infectology

INTRODUCTION TO INFECTOLOGY
CONCEPT OF INFECTIOUS DISEASES;
SPECIAL INFECTIOUS DISEASES;
CLASSIFICATION;PRINCIPLES OF DIAGNOSTICS,
TREATMENT AND PROPHYLAXIS
V. V. Zakhlebayeva, Candidate of Medicine, assosiate professor
MEDICAL INSTITUTE;
SUMY STATE UNIVERSITY
DEPARTMENT OF EPIDEMIOLOGY AND INFECTIOUS DISEASES

After finishing the course, "Infectious diseases" , student should understand the
following:
Classification of infectious diseases.
The periods of development of an infectious disease.
Clinical symptoms and syndromes of an infectious disease.
Clinical features of different nosological forms.
Features of epidemiological process, its components at various infectious disease.
Clinical and epidemiological indications in hospitalization of patients with infectious
disease.
Rules of hospitalizing/admitting patients with infectious diseases.
Maintaining the epidemic measures in hospitals and at home before the treatment.
Basic diagnostic methods of infectious diseases.
Basic complications and courses of infectious diseases.
Principle treatment of infectious diseases.
Principle and prophylactic methods of infectious diseases.
Organization of emergency anti-epidemic measures for quarantine diseases.
Clinical manifestations of emergency conditions on infectious diseases .
Principles of out patient management to patients with: a) intestinal infections, and b)
with air-borne infections.
Clinical manifestations of helminthiasis and methods of diagnosis.
Deworming measures.
Functions of infectious diseases cabinet at Outpatient department (OPD)

Must be able to;
 Collect anamnesis of the diseases,
Collect epidemiological anamnesis,
Carry out clinical examinations for patients with infectious disease,
Set a previous diagnosis of infectious disease,
Make a plan of examination,
Determine the need for hospitalization or discharging the patients,
Select the main clinical syndrome or symptom,
Evaluate the results of laboratory investigations (clinical,
bacteriological, serological).
Assign adequate etiotropic therapy, to determine the frequency of
administration of antibody(chemotherapy) whether given once or in
daily doses with respect to a certain infectious disease,
Assign adequate oral rehydration and infusion, to determine the
composition, amount and doses of drugs that are administered,
Assign adequate detoxication therapy, to determine the composition,
amount and dosage regimen,
Assign serotherapy, prior to desensitization,
Prescribe the necessary medical drugs,
Establish the presence of a medical emergency and complication,
Carry out fecal analysis from patient,

Collect materials from the patients for bacteriological, virological, serological,
biochemical and other tests (blood cultures, vomiting mass, gastric washings,
feces, mucus and smear taken from the nose and throat).
Collect smear from the nasal mucosa for rapid diagnostic immunological studies
with influenza and SARS.
Carry out the preparation of thick blood smears and for research on malaria,
Perform allergic skin-test to determine the results,
Wash out the stomach,
Determine the indications of lumbar puncture and analyze the results of laboratory
tests of cerebrospinal fluid,
Make a plan of treatment to patients with an intestinal infection at home,
Make a plan of treatment to patients with air-borne infection at home,
Make a plan for conduction of an anti-epidemic measures at home.
Make a plan of vaccination at the clinic.
Fill in the required documentation during the initial identification of an infectious
patient.

Should acquire the practical habits of:-
Carrying out the allergy tests:
-Skin test with brucelin;
-Skin test to allergen ornithosis;
-Skin test with toxoplasmin;
-Skin test with tulaerin;
-Skin test with anthraxin.
The introduction of therapeutic sera.
Blood samples for blood culture.
Blood samples for sterility.
Blood samples for serological studies.
Blood samples for biochemical studies.
Examination of blood for malaria.
Collection of material for virological investigations.
Collection of material for bacteriological examination (feces, urine, bile).
Lumbar puncture.
Gastric lavage.
Fractional duodenal intubation.
Determination of urinary bile pigments (Rosina sample).
Sigmoidoscopy.

After completing the course of infectious diseases in accordance with the standards
of higher education (educational-qualification, educational and vocational training
programs and diagnostics of quality in higher education),the student must master
the ability to solve some typical problems in the implementation of a determined
production functions.

REGULATIONS FOR “MRS”
Learning requires a 100% of visiting lectures and practical classes.
Rating of discipline, "INFECTIOUS DISEASES" consists of 200 points.
 Curriculum of infectious diseases spread across five content modules, which
has total of 180 hours, including 20 – Lectures, 80 - practical classes and 80-
for self-study
In each practical classes, student receives two points(marks): - for control
test-maximum of- 0.5 points, for the practical work -maximum of- 2.5 points,
for total control - 4-6 points, of which 0.5 - for computer control of others - for
oral (written) response.
 Maximum number of credits that a student can score before module is 200,
including the ongoing training activities - 120 points, the results of the final
module control - 80 points.

RATING IN THE DISCIPLINE,
"INFECTIOUS DISEASES"
CONSISTS OF 200 POINTS.
The system provides additional
incentives:
Participates in the students' circle with
the training of student work (published
abstracts) + 4 points for the final
evaluation scores;
Participation in a students’ conference +
4 points for the final evaluation;

When in doubt, try to speak
clearly.
…”Murphy Law”

FINAL ANNUAL MONITORING INCLUDES:
Computer testing (50-100 theoretical questions) and
the solution of practical problems.
- Practical tasks include: examination of the patient, a
plan to survey the patients(ward round), the treatment
plan with mandatory prescriptions (10 points -
computer test and 30 points - a practical problem).
Solving situational tasks, interview (40 points).
The final control module is enrolled, if the student
has scored at least 50 points from possible 80.

An Infe c tio n (infectio /lat./ contamination, pollution) - penetration in the
organism of morbific microorganisms and appearance of difficult complex of
interaction processes. I.I. Mechnikov considered that «Infection was a fight
between two organisms».
An infe c tio us p ro c e s s is an aggregate of physiological protective and
pathological reactions, occurring in the certain terms of environment in reply to
the influence of infectious agents (A.F. Bilibin, 1962).
An infe c tio us d is e a s e is an extreme degree of development of infectious
process. Manifests in different signs and changes of biological, chemical, clinical
and epidemiological order. A «infectious process» and «infectious disease» are
not equivalent concepts. Everybody daily faces millions of microbes, but the
process of interaction ends, as a rule, with the victory of macro organism - and
illness does not develop.

FORMS OF CLINICAL COURSE OF INFECTIOUS
DISEASES
In the case of equilibrium between macro- and microorganisms, it would be well
to talk about carriage. In this situation a person is not able to eradicate an
infectious agent, but a microorganism does not cause a disease. The clinical
and morphological signs of infection are absent (bacteria, viruses, protozoa),
there is no antibody generation. Such «healthy» carrier meets rarely.
There are no clinical signs at the in apparent (latent) form of infectious disease,
but antibody generation is present, some morphological signs of pathology are
possible.
The subclinical form of infectious disease proceeds with minimum clinical signs.
Clinical form of infectious disease is the clinically expressed illness.

MECHANISMS OF DEVELOPMENT OF
INFECTIOUS DISEASES: RECURRENCE,
A cycle means totaPl dEuraRtioInO oDf dIisCeaIsTe:Y, STAGING
A clinical cycle lasts from the first to the final date of illness (from appearance
of the first symptom to disappearance of the last signs of disease);
Pathogenetic cycle – is longer, including latent period (from penetration of
infectious agent to appearance of the first symptoms) and period of
morphological and functional renewal of organs and tissues.

INFECTIOUS DISEASE PASSES THE
FOLLOWING PERIODS:
- INCUBATION - an infectious agent is already in an organism,
although it is not yet influence on its state;
- PRODROME - the first clinical signs of disease;
- CLINICS - the most typical and characteristic clinical signs of
illness;
- RECONVALESCENCE - completion of forming of immune answer.

THE CLINICAL PERIOD IS COMMONLY
SUBDIVIDED INTO THE STAGES:
Growths of symptoms (during several days, sometimes – hours, till maximal
expression)
Height (most expressed signs, without a substantial dynamics)
Recession (reverse development of symptoms)

CLINICAL COURSE OF INFECTIOUS DISEASES
Clinical infection can have an acute, sub acute and chronic clinical
course. Most often there are acute forms - with the expressed clinical signs,
acute beginning, short duration cycle. As a rule, these infectious diseases
are accompanied by a good immune answer. Some infections have an
acute clinical course only: flu, measles, plague.
A subacute (protracted) clinical course proceeds longer than ordinary term
(cycle); it can be the stage of conversion into the chronic process.

CLINICAL COURSE OF INFECTIOUS DISEASES
 The chronic clinical course of infections meets relatively rarely; it is
characteristic for brucellosis and parenterally viral hepatitis (B, C, G). The
chronic clinical course of infectious diseases is conditioned by the protracted
staying of infectious agent in an organism and autoimmune processes.
Clinically it is characterized by an undulating clinical course with remissions,
relapses and intensifying. Rational therapy can lead to the reconvalescence
or, at least, improvement and protracted remission.
 The blazing (fulminant) form of infections develops very quickly – in several
hours, clinical course is malignant, as a rule – with a lethal outcome. Meets,
for example, at meningococcemia.
 The latent (or persistent) form of infection can be considered as the variant of
unsteady equilibrium between micro- and macro organism. It arises up, as a
rule, at persons with hyposthenic immunity, related with forming of L–forms
and imperfect forms of infectious agents, proceeds over 6 months and has a
favorable end in most cases. Example of latent infection is herpes.
 Slow infections develop at penetration of viruses (virions, priones), they are
characterized by the protracted latent period (months, years), slowly
progressing clinical course, by development of pathological processes
mainly in one organ or system (CNS is more frequent than others), by an
oncogenic orientation and lethal outcome. Example: HIV-infection.

A DISEASE CAN BE CAUSED BY ONE OR SEVERAL
INFECTIOUS AGENTS
An infection, conditioned by one infectious agent, is called a monoinfection, by
several infectious agents – mixed infection. Mixed infection can arise up as a
result of simultaneous penetration of two and more infectious agents (co-infection)
or as a result of successive contamination (superinfection,
overlaying of one infectious agent on other).
For example, at contamination through blood, development of viral
hepatitis B, C and D can be as co infection, and as super infection.
The repeated contamination by the infectious agent of the same kind is
called reinfection.

A.F. BILIBIN CREATED A CLASSIFICATION OF
SYMPTOMS RELYING ON THEIR
MEANINGFULNESS FOR DIAGNOSTICS OF
INFECTION:
leading – meet at many diseases (rise in temperature, head pain, insomnia, pain in
muscles and joints, hepatosplenomegaly) – suggest the group of infections;
supporting (optional) meet at 2-4 diseases (excrements with blood and mucus – at
a dysentery, amebiasis, balantidiasis; meningeal symptoms – at meningitises of
different etiology);
decisive (absolute) – at their presence the diagnose is clear enough, as they meet
only at one disease.

CLASSIFICATION OF INFECTIOUS DISEASES
In the 19th Century, infectious diseases were classed as c o nta g io us (transmissible
from person to person),m ia sm a tic (transmitted through air), and c o nta g io us -
m ia sm a tic .
Late in the 19th century, in view of advances made in bacteriology, the diseases
were classified according to their etiology.
These classifications could not satisfy Clinicians or Epidemiologists since the
diseases with different pathogenesis, clinical course and epidemiologic
characteristics were united in one group.
Classifications based on and epidemiological signs proved ineffective too.
The classification proposed by Gromashevsky seems to be more
reasonable than many others;
It is based on the location of infection in the macro organism. In accordance with the
main sign that determines the transmission mechanism, all infectious diseases are
divided by the author into FOUR groups:-
I. Intestinal Infections
II. Respiratory Infections
III. Blood Infections
IV.Skin infections.

According to Gromashevsky, each group is subdivided into anthroponoses and
zoonoses; their epidemiology and prevention differ substantially.
a) Intestinal Infections:- Intestinal infections are characterized by location of the
causative agents in the intestines and their distribution in the environment with
the excrements.
-If the causative agents circulates in the blood( typhoid fever, paratyphoid fever A
and B, Leptospirosis, viral hepatitis, brucellosis, etc), it can also be withdrawn
through various organs of the body, e.g. the kidneys, lungs, the mammary
glands.
-As a microbe is released into the environment with feces, urine, vomitus(cholera),
it can cause disease in a healthy person only after ingestion with food or water.
In other words, intestinal infections are characterized by the fe c a l-o ra l m e cha nism
o f tra nsm is s io n.
-Maximun incidence of intestinal infections occurs usually during the warm
seasons.
-The anthroponoses includes typhoid fever, paratyphoid, bacterial and amoebic
dysentery, cholera, viral hepatitis A, poliomyelitis, helminthiasis (without the
second host).
-The zoonoses include:-brucellosis,l eptospirosis, salmonella, botulism etc.

- The main means of control of intestinal infections are sanitary measures that
prevent possible transmission of the pathogenetic micro organisms with food,
water, insects, soiled hands etc.
- Timely detection of the diseased and the carriers, their removal from food catering
and the like establishments is also very important.
- Specific immunization is only of the secondary importance in intestinal infections.
b) Respiratory infections:-This group includes diseases whose causative agents
parasitize on the respiratory mucosa and are liberated into the environment with
droplets of sputum during sneezing, cough, loud talks, or noisy respiration.
-People get infected when the microbes contained in sputum get on the mucosa of
the upper airways.
-If the causative agents is unstable in the environment, a person can only be
infected by close contacts with the sick or carrier (pertussis).
-Pathogenic microorganisms causing some diseases can persist for a period of time
in an enclosure where the sick is present. Infected particles of sputum or mucus
can dry and be suspended in the air. Some diseases of this group can spread
through contaminated linen, underwear, utensils, toys etc.
-Since susceptibility of people, and especially of children to respiratory infection is
very high, and since the infection is easily transmitted from the diseased(or
carriers) to healthy people, almost entire population of a given area usually gets
infected, and some people can be infected several times.

Some diseases of this group form a special subgroup of children's
infections(diphtheria, scarlet fever, measles, pertussis, epidemic parotitis,
chickenpox, rubella).
-A durable immunity is usually induced in children who sustained these diseases.
-The main measure to control respiratory infections is to increase non-susceptibility
of population, especially of children, by specific immunization.
-It is important to timely reveal the sick and carriers and also to break the
mechanism of infection transmission:-
 Control of overcrowding
Proper ventilation and isolation of enclosures
Using UV –lamps
Wearing masks, respirators
Disinfection and the like.
c) Blood infections:-The diseases of this group are transmitted by blood
sucking insects, such as fleas, mosquitoes, ticks, etc. which bite people and
introduce the pathogenic agent into the blood.
-Tick-borne encephalitis, Japanese B encephalitis and some other infections are
characterized by natural nidality which is due to specific geographic, climatic, soil,
and other conditions of infection transmission.

The morbidity is the highest during the warm season which coincides with the
maximum activity of the transmitters-ticks, mosquitoes, etc.
Control of blood infections includes altering natural conditions, improvement of
soils, draining swamps, destroying sites where the insects multiply, disinsection
measures against mosquitoes, ticks, etc., detoxication sources of infection by
their isolation and treatment carrying out preventive measures.
-If the source of infection are rodents, measures to control them are taken.
-Active immunization is also effective.
d) Skin infections:- The diseases of this group occurs as a result of
contamination of the skin or mucosa with the pathogenic microorganisms. They
can remain at the portal of infection(tetanus, dermatomycoses), or affect the
skin, enter the body and be carried to various organs and tissues with the
circulating blood( erysipelas, anthrax).
-The transmitting factors can includes bed linen, clothes, plates and dishes and
other utensils that can be contaminated with mucus, pus, or scales.
-Pathogenic microorganisms causing venereal diseases, rabies, AIDS, and
some other diseases are transmitted without the agency of the environmental
objects.
Wound infections are characterized by damage to the skin as a result of
injury(tetanus, erysipelas).

The main measures to control skin infections includes:-
 Isolation and treatment of the sources of infection,
Killing diseased animals, homeless dogs and cats,
Improving sanitation and living conditions of population,
Personal hygiene,
Control of traumatism and,
Specific prophylaxis.
PREVENTION OF INFECTIOUS DISEASES
Prevention and control of infectious diseases includes the
following:-
1)Mass-scale measures aimed at improvement of public
health, prevention and spread of infectious diseases;
2)Medical measures aimed at reduction of infectious
morbidity and eradication of some diseases;
3)Health education and involvement of population in
prevention or restriction of spread of infectious diseases;
4)Prevention of import of infectious diseases from other
countries.

-Improvement of people’s well being, adequate housing, medical aid, and
health education should be adequately planned and carried out.
-Preventive sanitary supervision is also necessary.
-Industrial objects, residential houses, children’s and medical institutions should
be constructed with strict adherence to the special sanitary requirements that
are intended to improve labour and living conditions, prevention of onset and
spread of infectious diseases.
-Preventive measures aimed to control infectious diseases taken by medical
personnel are divided into Preventive and Anti-epidemic.
-Preventive measures are carried out regardless of the presence or absence of
infectious diseases at a given time and locality.
These measures are aimed at prevention of infectious diseases.
-Anti-epidemic measures are necessary when an infectious disease develops. It
has already been said that the following three basic factors are necessary for
development of an epidemic:-
 The source of infection
Transmission mechanism
Susceptibility of population.

DIAGNOSTIC OF INFECTIOUS DISEASES
Diagnostics of infectious diseases must be early, clinical
(primary), epidemiological, taking into account the complex
of received data, cyclic, period and stage of disease.
METHODS OF DIAGNOSIS AND THEIR VALUES
1) Anamnesis – of disease, epidemiological, life (suffered
in the past infections may recur, acute: for example,
chronic hepatitis, spotted fever).
2) Clinical examination.
3) General clinical laboratory research.
4) Express-diagnosis: Immune fluorescence, Immune
enzyme reaction.
5) Bacteriological diagnosis (determining of causative
agent) is used at all bacterial infections, microscopic- at
diphtheria, meningococcal infection, cholera.
6) Serological diagnostics is necessary for doctor for
acknowledgement of the majority of infectious diseases.
The level of antibodies is necessary for investigating in

7) Biochemical methods of research are necessary at many infectious diseases,
especially – at viral hepatitis.
8) Intracutaneous tests are applied at some infections and have the different
importance.
9) Instrumental diagnostics is applied at intestinal infections (rectomanoscopia),
at meningitis (lumbar puncture).
10) Morphological diagnostics is necessary at diagnostics and curation of
patients with chronic hepatitis.

TREATMENT OF
INFECTIOUS PATIENTS
Complex therapy should be given along with specific treatment, that must be
pathogenetically substantiated and individual for each particular patient, depend
on the severity of the patient’s condition and the period of the disease.
 Specific therapy is used to eradicate or neutralize the infective agent and its
metabolites, and to strengthen the defensive forces of the patient.
 Chemotherapy;
 Serotherapy
 Immunotherapy are indicated.
a) Chemotherapy:-Chemical drugs that produce a specific action on the pathogenic
agent can be synthetic or vegetable by their origin. Synthetic antibiotics are
also used.
-When a chemical drug is administered, it inhibits multiplication and
vitality of the pathogenic micro organisms. Further eradication of the agent is
ensured by the defensive force of the patient.

Sulpha drugs –include prolonged- action preparations such as sulphapyridazine,
sulphadimethoxin, and other preparations. Limited use of these preparations is
explained by the development of resistant strains and the irritation effect on the
gastric mucosa( nausea, vomiting, gastric hypo secretion).
-Allergic rash and stones in the kidneys are also possible.
-Taking great amount of alkaline drinks prevents formation of such stones.
Derivatives of 8-oxyquinoline(intestopan mexaform, mexase, 5-NOK) are used to treat
intestinal infections. These preparations do not inhibit normal interstinal flora,
decrease putrefactive and fermentative process in the intestines. Prolonged use
of these drugs can cause peripheral neuritis and impair of vision.
Nitrofurans(furadonin, furacin, furazolidone, furagin) are effective against intestinal
infections.
Antibiotics are efficacious in infectious patients. They shorten the course of the
disease, prevent complications and decrease the mortality rate.
When prescribing antibiotics, duration of antibiotics therapy, the dose and the
route of administration(oral, intramuscular, intravenous) , duration of treatment
and toxicity of the antibiotic. Antibiotics give prompt therapeutic effect.

 Chloramphenicol has a broad spectrum of its action and is effective against
intestinal infections(typhoid fever, paratyphus A and B), rickettsiosis,
spirochaetosis.
 Penicillins(salts of benzypenicillin, bicillin, ampicillin) are highly effective
against meningococcal infection and anthrax.
 The Tetracycline(hydrochlorides of tetracycline and doxycycline,
rondomycin) are effective against rickettsiosis, intestinal infections tularemia,
and plague.
b) Serotherapy:-Serum of immune animals and people is used to treat
infectious diseases. The preparations are classed as antitoxic(containing
antitoxins) and antibacterial(containing bactericidal antibodies).
-Antitoxic sera are highly effective. They are prepared by hyper immunization of
animals( e.g.. Horses bulls, and other animals) with specific exotoxins.
-Antitoxic sera are used to treat diphtheria, botulism, gaseous gangrene, etc.
The serum should be administered as early as possible, before the toxins
produce irreversible changes in the organs and tissues. Antibiotics serum
should be given in various doses depending on severity of the disease. It can
be administered intramuscularly, and in exceptional rare cases, intravenously.
-Antibacterial sera are prepared by hyper immunization of animals with bacterial
vaccines. They are given in milliliters(50-100-150ml) depending on severity of
the disease.

PATHOGENETIC THERAPY
Includes many medical measures aimed at elimination of toxemia by
detoxicating or infusion-detoxicating therapy, and glucocorticosteroids therapy,
depending on the clinical form of the disease, restoration of water-salt balance
equilibrium by rehydration therapy, normalization of the cardiovascular and
nervous function, and also increasing the impaired bodily functions by
stimulating therapy.
Detoxication therapy:- is given in mild and moderate forms of infectious
diseases. It is sufficient to give the patient ample drinking:-Juice, stewed fruits,
mineral water, boiled water, tea, etc.
Patients with pronounced toxemia are given infusion-detoxicating
therapy directed at neutralization and elimination from the body of microbial
toxins and metabolites. To that end, haemodez is given intravenously,
polyglucin, rheopolyglucin, blood plasma, and 10% albumin solution should be
given for severe hypotension. A 5% glucose solution and isotonic sodium
chloride solution should also be administered. The solutions can be infused
separately or wherever possible, in mixtures(drip infusion).

 Glucocorticosteroid therapy:- Is given to patients in septic shock and
acute adrenal failure(meningococcal infection, influenza, hemorrhagic fever,
poliomyelitis, typhoid fever, louse-borne typhus, salmonellosis, dysentery
diphtheria, plague, cholera).
Glucocorticosteroids(prednisolone, dexamethazone, triamcinolone, cortisone,
hydrocortisone) are given in large doses, better intravenously.
For example, a daily dose of prednisolone is 120-300 mg, and more, after
recovery of the patient from shock the daily of the preparation is decreased 2-4
times and is given intramuscularly or per os with control of arterial pressure.
Rehydration therapy:- Is directed at restoration of the water-salt equilibrium
and is used in gastrointestinal forms of intestinal infections attended by
incoercible vomiting, frequent stools(profuse diarrhea), and development of
hypovolaemic shock.
The amount of repleted salts, their composition and the way of administration
depend on the rate and the degree of dehydration and the character of water-salt
disturbances.

Four degrees of dehydration are differentiated:-
1st degree dehydration:- The patient loses water in the amount of 1-3% of
the body weight.
The patient develops moderate thirst, dryness of the mucosa and moderate fatigue,
stools are semi liquid or waterly,3-10 times a day, vomiting is rare.
2nd degree dehydration:-The loss of liquid is 4-6% of body weight. Stools
are ample, watery or resembling rice water, 10-20 times a day, vomiting is
frequent(5-10 times).
The patient develops thirst, the skin and mucosa are dry, the lips, fingers, and
feet are cyanotic, fatigue is marked. Muscular cramping in the calves, wrist, and feet, signs
of blood thickening develop, tachycardia, hypotension and oliguria are seen.
3rd degree dehydration:- The loss of liquid is 7-9% of body weight. Stools
are frequent and ample, vomiting and cramping of the limb muscles are seen,
the skin and mucosa are dry, washerwoman’s hands symptom develops, hypotension
is pronounced, oliguria or even anuria develops.
4th degree dehydration(the algid form):-The liquid loss is 10% of
body weight. The disease begins acutely. Diarrhoea and vomiting discontinue at
the beginning of the disease. The body temperature falls to 35-35.5˚C,
peripheral pulse and arterial pressure are absent, anuria and aphonia
develop.Cyanosis is intensive, muscles are cramping,the facies are pinched, the
eyes and cheeks are retracted(sunken eyes).

• In 1st and 2nd degree of dehydration, the patient is given gastric lavage
and then one of the following solutions( to drink in small portions):-
1. Glucose-salt mixture(3.5g of sodium chloride, 2.5g of sodium
hydrocarbonate,1.5g of potassium chloride, and 20g of glucose
dissolved ex tempore in 1 litre of drinking water); a solution containing 4g
of sodium hydrocarbonate, 5g of sodium chloride, and 1g of potassium
chloride; a solution containing 2.6g of sodium acetate, 1g of sodium
hydrocarbonate,6.2g of sodium chloride and 0.3g of potassium chloride;
or Locke-Ringer solution containing glucose or sweet tea. If
vomiting,continues, the liquid should be administered through a
nasogastric tube.
In 2nd and 3rd degree of dehydration,and especially 4th degree, the patient
should be given intravenously polyion buffer solutions preheated to 38-
40ºC. In addition to the mentioned solutions, used also are solutions
containing 2.0g of sodium acetate, 5.0 g of sodium chloride,1.0g of
potassium chloride, or a solution containing 3.6g of sodium acetate,
4.75g of sodium chloride, and 1.5g of potassium chloride, or a solution
containing 3.3g of sodium lactate,4.75g of sodium chloride, and 1.5g of
potassium chloride.

• Treatment includes two states:-primary rehydration (repletion of the liquid
lost before rehydration therapy is started) and compensatory (replenishment
of the liquid lost during treatment).
• In 3rd degree of dehydration, the solution is given intravenously at a rate of
100ml/min.
• In 4th degree of dehydration, and if hypovolaemic shock develops, one of
the specified solutions is infused at a rate of 100-120ml/min, 5-7litres during
60-90 minutes.
• After the patient’s condition is no longer critical, the second stage of
treatment begins. The solution is now infused by drip at a rate of 100-150
drops per minutes with a gradual reduction of the rate to 60 and then 20-10
drops per minute.
• Liquid infusion can be suspended depending on the degree of improvement
of the patient’s condition and normalization of the water salt metabolism.
• If necessary, the glucose salt solutions are given per os, by small portions at
short intervals.

2. Stimulating therapy:- is aimed at normalization and intensification of
dysfunctioning organs and systems.
• Cardiovascular dysfunction develops due to the action of toxins liberated by
the pathogenic agent on the myocardium and the vessels.
• Dehydration of the body causes thickening of the blood, evokes circulatory
and haemostatic disorders.cordiamine, caffeine, ephedrine, and other
norepinephrine are given to neutralize the action of toxins.
3. Vitamin therapy:- is useful from the very beginning of the disease. Vitamins
given together with hormones and enzymes catalyze the metabolic processes.
Vitamin B facilitates correction of some nervous disturbances, vitamin A, C,
and B decrease the toxic effect of antibiotics, vitamin C,B,PP and P
produce an anti-inflammatory and detoxicating action, vitamin P decreases
brittleness and permeability of vessels, Vitamin K promotes blood coagulation.
Vitamins are given per Os or intravenously with glucose solutions (vitamin C as
a 5%solution of ascorbic acid, vitamin B as a 6% solution).

PROPHYLAXIS OF INFECTIOUS DISEASES
• At the last decades, certain successes were achieved in fighting with
infectious diseases, massive epidemics of most dangerous infectious
diseases (epidemic typhus fever, plague, small pox, tick borne relapsing
fever and other). The struggle is realized successfully with diphtheria,
poliomyelitis, measles, and many zoonotic infections. Undoubt success is
achieved in malaria control.
• Every year multiple cases of streptococcus and staphylococcus infections,
cholera, helminthiasis, viral hepatitis, meningococcal infection and diseases
caused by conditional pathogenic flora are registered in the world.
Thus, prophylaxis of infectious diseases is actual question!!.
• The measures of prophylaxis of infectious diseases may be conditionally
divided on 2 groups:-general and special measures.
• The general measures are state measures directing on increase of material
favorable condition, improvement medical service and conditions of work
and rest of the population, sanitary technique, hydrotechnic measures and
also international measures in attitude of quarantine infections.

It is known about 3 links for development of epidemic process:-
1. The sources of infection
2. Ways of the transmission and
3. Susceptibility of the organism;
The absence or rupture either of this link leads to cessation of epidemic
process.
There are 3 groups of prophylactic measures:-
. The measures directing on the source of infection, it’s elimination.
. The measures directing on the mechanism of the transmission of infection.
Their purpose is rupture of the ways of transmission of infection.
. The measures directing on increasing of insusceptibility of population to
infection.
Prophylactic measures directing on the source of infection play an
important role. It is known that when antroponotic infection, the source of
infection is sick man or a carrier of the agent.
Also the source of infection in zoonotic infections is sick animal.
And the prophylactic measures of this group are diagnostic, isolative, medical
and regimen-limitary measures.

In some infectious diseases, hospitalization into infectious hospital is obligatory
(especially dangerous infections, typhoid fever, epidemic typhus, diphtheria,
meningococcal disease).
In other diseases, isolation may be at home if epidemiological and clinical features are
absent( like shigellosis, escherichiosis, measles and others.)
An important prophylactic measure is active revealing of carriers and
their sanation.!!
Revealing of carriers is performed in focuses of infection, among reconvalescents, and
also among persons of food establishments, water pipe stations, and children’s
establishments.
It is necessary to perform their bacteriological examination and treatment.
In prophylaxis of infectious diseases, an important measure is influence on mechanism
of transmission of infection.
Transmission of the agent from sick man to healthy man is realized with the help of different
factors( water, food, dust, air, soil and others.
Specific prophylaxis is performed with the help of vaccines, anatoxins serum, gamma globulins.
Vaccines and anatoxins create active immunity, while serum and gamma globulins creates passive
immunity.

Introduction to Infectology

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