Introduction To Microbiology & Common Microorganisms.pptx

Introduction To Microbiology
& Common Microorganisms
Prepared by
Akshata A Jain
Asst.prof.
KYDSCT’s College of Pharmacy

• The chapter deals with basics of microbiology
with respect to infectious disease.
• It deals with basics of epidemiology of
diseases & defines commonly used
terminology in epidemiology.
• A separate section deals with commonly
observed respiratory, intestinal, arthropod-
borne, surface infections & sexually
transmitted diseases.

• Epidemiology is the study of determinants,
distribution & frequency of disease indicating
who gets the disease & why.
It has following features:
Epidemiologist study sick people.
Epidemiologist study healthy people.
They determine the crucial difference between
those who get the disease & those who are
spread.

Epidemiologist study exposed people.
Epidemiologist study non-exposed people.
They determine the crucial effect of the exposure.
Applications of epidemiology:
To study the cause of disease.
To determine causative agent.
To determine mode of transmission.
To determine contributory factor.
To identify & determine geographic factors etc.

• Definitions :
Epidemic refers to an often & sudden increase in
the number of cases of a disease, above what is
normally expected, in the population in that area.
The amount of particular disese that is present in
a community is referred to as endemic level of
the disease.
It refers to an epidemic that has spread over
several countries or constituent , usually affect
ing a large number of people

Contact (direct/ indirect), droplet, airborne &
vectors are four modes of transmission of
infection.
a quarantine is a restriction on the movement
of people, animals & goods which is intended
to prevent the spread of disease.
It involves placing away of patients at specific
distance to avoid the spread of infection.

It is the time elapse between exposure to a
pathogenic organism & when symptoms & are
first appearant in patients.
It attempts to find all contacts of a confirmed
case of infectious diseases, in order to test or
monitor them for infection.
Outbreak is a sudden increase in occurences of
a disease when cases are in excess of normal
expectancy for the location.

Epidemiology of communicable
diseases:
• The epidemiology is derived from greek words “epi”
indicating ‘upon’ & “demos” indicating ‘people’.
• The principles of epidemiology were applied only for
communicable diseases; however it is now realized
that it could also be used for general medicine &
public health.
• An epidemiologist views the entire population.
• Epidemiological studies provide information on
occurrence & distribution of diseases & collect data
which may be useful in initiating control measures.

Following are major uses of epidemiology:
• To analyse the respective role of an agent, host
& environment in development & natural
history of a disease.
• To analyse occurance & distribution of a
disease according to characteristics such as
age, sex, race, occupation & heredity.
• To study outline & define problems of health
& disease by analysis of incidence, prevalance
& mortality.

• To help complete clinical picture & natural
history of a disease by group analysis.
• To estimate a person’s risk of developing a
disease & the chances of his/her survival
• To search for factors related to health &
disease by observation of group customs &
habits.
• To evaluate the need & effectiveness of health
service through field studies.

Agents of a disease may be physical, chemical
or biological.
1. Physical agents:
• The are mechanical, thermal or radient.
• The commonest example of a mechanical
agent is a motor vehicle.
• Extremes of cold & heat are thermal factors.
• X-ray, ꭈ-rays are examples of radient agents.

2. Chemical agents:
• These can cause illness by direct contact,
ingestion or inhalation.
• Example of inhalation agent is carbon
monoxide.
3. Biological agents:
It includes worms, insects, protozoa, fungi,
bacteria & viruses.
There are various factors on which
epidemiological incidence of a disease is
dependent. These factors are as follows:

Host :
• The body has a variety of defence mechanism.
• The primary defence include skin, hair & nails.
• The body develops immunity against infective
organism.
• Besides these, general factors like Age,sex &
colour.
• Hereditary & prior experience of the body with
a specific agent are also contributory factors
towards host response.

Environment:
• The environment may be favourable either to
host or to the infective agent.
E.g Survival of mosquito will influence incidence
of malaria.
Incidence & Prevalance
• While studying a disease, the epidemiologist
examines incubation periods, the extent of
communication, possible source of infection &
methods of transmission.

Mortality
• Mortality data is readily available from review
of death certificates.
• It is also important to comment on health
status of community.
Clinical picture of the disease:
• Description of clinical signs of a disease is
based on observations related to a group of
persons.
• Epidemiological study is required to estimate
the persons risk of developing a disease & his
chances of survival.

Habits & Customs:
• Habits relating to the cosumption of certain foods,
cooking pressures, cleanliness & handling of food &
milk contribute to the occurrence & distribution of
disease.

Methods of Epidemiological studies:
• Retrospective studies:
Under this procedure, already available records
are scrutinized. A group with the disease under
study is compared with appropriate control
group & their characteristics.
• Prospective studies:
Under this procedure, records are developed
from a study of population. A group with a
disease is compared with control group.
Prospective studies are generally more difficult
& time consuming to pursue.

• Experimental studies:
Experimental studies offer the best type of
investigations, however design requirements
are stringent & money required make this kind
of study much more difficult to initiate & carry
through than retrospective & prospective
studies.

Dynamics of Disease Transmission
All the epidemiological factors discussed earlier,
i.e. agent, host, environmental conditions,
habits & customs of the community, measures
of control for preventing the disease, immunity
of the individuals together decide dynamics of
disease transmission.
There are few important points about
communicable diseases which need special
mention.
• Modes of infection.
• Channels of infection.

I. Modes of Infection:
The modes of infection are of 3-types
a) Direct :
 This mode does not involve any intermediate host.
 It is called as contact infection.
 Diseases like tuberculosis, measles, influenza, syphilis are
spread through this route.
b) Indirect :
 In this case, infection is transferred indirectly through the
agency of a third person through a vector or vehicle.
 These vectors may be animate or inanimate.
 Inanimate objects include dishes, utensils, books etc.
 Animate objects may include arthropod insects.

c) carriers:
Human carriers of temporary or chronic type may
be responsible for spread of the disease. Disease
carriers are the persons, who harbour pathogenic
microorganisms of a specific infectious disease
without manifesting any signs & symptoms of the
disease. But who are still able to infect other
individuals.
They belong to 4-subtypes:
i. Precocious or incubation carriers:
These are the persons who harbour the infecting
agent during incubation period of the infectious
disease.

ii. Contact carriers:
These are the persons, who are on contact with
a case of an infectious disease & carry
microbes morphologically identical with those
of causative agents; such organisms are not
necessarily virulent.
iii. Convalescent carriers:
These are the persons who continue to
harbour the infective organism during
convalescence. They are sometimes called as
acute carriers.

iv. Chronic carriers:
These are the persons who harbour the
infective organism for a long period of time ( few
months) after recovery from the disease. Such
carriers are far more dangerous.

II. Channels of Infection:
There are 3- routes by which an organism can enter
into human body
1. Skin: Some microorganisms may enter the body
through skin. Biting of insects or animals may be
the most probable cause e.g. Malaria, rabies etc.
2. Inhalation : Inhalation of air carrying microbes is
responsible for infectious diseases.
e.g. Pulmonary tuberculosis, Covid-19
3. Ingestion: Use of infected food or drink may
cause infection through the digestive tract.
e.g. Cholera, enteric fever.

Types of Diseases:
The diseases have: been classified
into 4 categories.
The first section is
on respiratory diseases.
I. Respiratory diseases
a) Chicken Pox:
Viruses infect human beings, animals, birds &
insects. Based on genetic, antigenic & ecological
criteria, the family poxviridae has been classified
into 2 sub families: Chordopox virinae & Entomopox
virinae.
Pox virus diseases are characterized by skin lesions
which may be localized or generalized.

Causative agent:
• For chicken pox, the causative agent is variola
virus or varicella zoaster.
Symptoms:
• It is characterized by sudden onset of fever,
chill, headache, severe backache continuing for
3-4 days.
• On the 4th day, temp falls & a rash appears,
which passes through stages of macule,
papule, vesicle & pustule forms.
• Then it crusts & finally scabs which fall off at
about end of third week.

Transmission :
–Acquired by inhaling virus containing
particles, trapped in tiny droplets
released into the air from the nose or
throat of an infected person .
–The virus enters the body by infecting
cells in the respiratory tract.
–It spreads to many other parts of the
body, including the skin, where it causes
the characteristic rash.
–It is most communicable during early
stages of the disease.

Pathogenesis:
• Varicella-Zoster Virus (VZV) is transmitted
through inhalation of infected respiratory
secretions or contact with infectious skin lesions.
• Typically, the virus is spread via coughing and
sneezing, as this allows viral-containing droplets
to be come airborne.
• VZV has an incubation period of about 10-21
days and is most contagious through physical
contact a few days before symptoms occur.

• During this incubation period, the virus
spreads to the lymph nodes, the liver, and the
lungs. This process known as primary viremia.
• As the incubation period progresses, the virus
makes its way to the skin via both CD4+ and
CD8+ T cells, initiating secondary viremia.
• As the infection progresses, small skin vesicles
filled with pus and infected cell particles form
on the skin surface. These lesions are the 'pox'
of chickenpox

Laboratory Diagnosis:
• Earlier, laboratory diagnosis was based on
isolation & identification of virus using
embryonated eggs inoculated with pustular
fluid.
• Diagnosis was performed using serological
tests.
• Currently the method of choice is electron
microscope of negatively stained smears from
vesicle fluid.
• Variola virus appears as brick shaped.

Prevention:
• The best way to prevent chickenpox is to get
the chickenpox vaccine. Children, adolescents,
and adults should have two doses of
chickenpox vaccine.
• Most people who get the vaccine will not get
chickenpox. If a vaccinated person does get
chickenpox, it is usually mild— with fewer
blisters and mild or no fever.
• The chickenpox vaccine prevents almost all
cases of severe disease.

• There are three types of response to vaccination:
1. Primary - (in previously vaccinated person)
2. Accelerated
3. Immediate reactions - (in case of revaccination)
• Primary reaction is characterized by appearance of a
papule after 3 - 5 days of inoculation which enlarges in
size and develops secondary erythmia.
• The vesicle becomes depressed in the centre and by 8th
or 9th day the vesicle changes to a pustule and there is a
high fever associated with lymphadenopathy.
• The pustule dries up after 10th day and a scab forms
which takes a week to separate, leaving a typical
vaccination scar.

Role of pharmacist in education &
prevention:
• The best way to prevent chicken pox is to take the
vaccine.
• In addition to vaccination, one can help prevent
the spread of chickenpox by practicing good
hygiene and washing your hands frequently.
• Reduce your exposure to people who have
chickenpox.
• If you already have chickenpox, stay at home until
all of your blisters have dried and crusted over.

b) Measles :
Causative agent :
Viral origin of measles was established in 1911 by
transmitting the disease to monkeys after
inoculation of filtrates of blood and
nasopharyngeal secretions of patients of
measles. The virus was isolated in monkeys and
human kidney cell cultures by Enters and Pebbles
in 1954. Measles virus belongs to the genus
Morbilli virus.

Clinical Presentation:
• After incubation period of 10 - 14 days, rash
appears on the skin.
• There are three stages in the natural history of
measles.
1. Prodromal stage.
2. Eruptive stage, and
3. Post-measles stage.
1. Prodromal stage begins ten days after infection,
and lasts till day 14. It is characterised by fever,
sneezing, nasal discharge, cough, redness of eyes,
lachrymation and photophobia. It may be
accompanied by vomiting or diarrhoea.

2. Eruptive phase is characterised by a typical,
dusky-red rash beginning behind the and
spreading within few hours to face and neck.
Within 2 - 3 days it extends to love extremities.
If there are no complications, lesions and fever
disappear within 3- 4 days.diagnostic sign.
3. During post measles stage, the child may
loose weight and remain weak for few days
there is failure in recovery, a gradual
deterioration into chronic illness leads to
increases susceptibility to other bacterial and
viral infections.

prevention:
• By active immunization.
• Measles live vaccine is given subcutaneously
at about 12 months of age.
• Vaccination is contraindicated in children with
immunological deficiencies.

c) Rubella :
• Rubella, also known as German measles or three-day
measles, is an infection caused by the rubella virus.
• A rash may start around two weeks after exposure and
last for three days.

Causative agent:
• The disease is caused by the rubella virus, in
the genus Rubivirus from the family
Matonaviridae, that is enveloped and has a
single-stranded RNA genome.
• The virus is transmitted by the respiratory
route and replicates in the nasopharynx
and lymph nodes.
• The virus is found in the blood 5 to 7 days
after infection and spreads throughout the
body.

Clinical presentation:
• Acute onset of generalized maculopapular rash.
• Fever higher than 99°F (37.2°C)
• Arthritis, lymphadenopathy or conjunctivitis
• In children, rash is usually the first sign of
disease.
• In older children and adults, there is usually a 1 to
5 day prodrome with low-grade fever, malaise,
lymphadenopathy, and upper respiratory
symptoms preceding the rash.
• Lymphadenopathy may begin a week before the
rash and last several weeks.

prevention
• The MMR vaccine protects against all three
diseases.
• It contains weak, but live, strains of each virus
that let the body build immunity against them.
• The vaccination is especially important for
children and women of childbearing age.
• More than 90 percent of those who receive the
vaccination never contract rubella.

D) Mumps:
• Mumps is a viral disease caused by the mumps virus
which has a preference for glandular & nervous tissues.
• These symptoms are usually followed by painful
swelling of the parotid glands.

Causative agent :
• The causative agent is Myxovirus parotoditis.
• It is a RNA virus of myxovirus family.
• The disease can be spread by droplet infection.
• It is generalized virus infection.
• It is characterized by pain & swelling of parotid
glands.
• A common complaint by children is of ear ache.
• The swelling subsides slowly over 1-2 week.

prevention
• Mumps is preventable with vaccination.
Mumps vaccines use live attenuated viruses.
• The vaccine is recommended for children over
1 yr of age.
• The vaccine should not be administered to
preganant women, patients receiving
immunosupressive therapy or those who are
severly ill.
• The disease is highly infectious.

e) Avian flue:
• It is a viral infection spread from bird to bird.
• It exists as 2-types of variants H5N1 & H7N9.
• "Bird flu" is a phrase similar to "swine flu", "dog
flu", "horse flu" or "human flu" in that it refers
to an illness caused by any of many different
strains of influenza viruses that have of been
adapted by a specific host.

• Bird flu is caused by a type of influenza virus
that rarely infects humans. More than a dozen
types of bird flu have been identified, including
the two strains that have most recently infected
humans — H5N1 and H7N9. When bird flu does
strike humans, it can be deadly.
• Bird flu occurs naturally in wild waterfowl and
can spread into domestic poultry, such as
chickens, turkeys, ducks and geese. The
disease is transmitted via contact with an
infected bird's feces, or secretions from its nose,
mouth or eyes.
Causative agent :

• Since the first H5N₁ outbreak occurred in 1987,
there has been an increasing number of avian
flue bird-to-human transmissions, leading to
clinically severe and fatal human infections. Due
to a significant species barrier between birds and
humans, the virus does not easily cross over to
humans. Exposure routes and other disease
transmission characteristics, such as genetic and
immunological factors that may increase the
likelihood of infection, are not clearly
understood.

• People who have fewer chances to contact with birds do not
belong to the high-risk group of HPAI.
• For being aware of bird flu pandemic, people should have
careful thought to adopt suitable Infection Control
Procedures.
• Protecting eyes, nose, mouth and hands from virus particles
is a major priority because these are the most common
passageways for a flu virus to transfer into the body. Bird flu
virus particles may also be transferred through clothing or
even shoes.
• Avoid contact with poultry, and maintaining good personal
hygiene is very important, too. Someone who has normal flu
should be more careful in avoiding contact with fowl.
prevention

• It is an acute respiratory tract infection caused by
influenza virus.
• The virus is of 3-types A,B &C.
• The influenza viruses are classified within the
family Orthomyxoviridae.
• There are 3-subtypes A,B & C
• These three viruses are antigenically distinct.
• There is no cross immunity between them.
• Influenza A &B viruses are responsible for
epidemics of disease.
• It is mainly spread by droplet infection.
f) Influenza:
Causative agent :

• The virus enters the respiratory tract and causes
inflammation and necrosis of superficial
epithelium of the tracheal and bronchial mucosa,
followed by secondary bacterial invasion. The
symptoms include fever, chills, aches and pains,
coughing and generalised weakness. Fever lasts
for 1 - 5 days, averaging 3 days in adults. The
most common complication is pneumonia which
should be suspected if fever persists beyond 4 - 5
days.

• Following preventive measures are recommended.
1. Good ventilation in public buildings.
2. Avoiding crowded places during epidemics.
3. Encouraging sufferers to cover their faces with a
handkerchief while coughing and sneezing.
4. Staying at home at the first sign of influenza.
The vaccine is not recommended to control spread in the
general population. Three kindsof vaccines are available:
(a) Killed vaccine
(b) Live attenuated vaccine and
(c) Newer vaccines.
prevention

The newer vaccines are sub-divided into three
types:
(i) Split-virus vaccine
(ii) Neuraminidase-specific vaccine
(iii)Recombinant vaccine.
Besides vaccines, two drugs (i) Amantadine and
(ii) Rimantidine are recommended in the
prophylaxis and therapy of influenza virus A
infection.

g) SARS:
• Severe Acute Respiratory Syndrome (SARS) was
first identified in 2003.
Causative Agent:
• It is a viral disease.
• SARS corona virus (SARS-CoV) is thought to be an
animal virus, probably bats, which spread to other
animals and first infected humans .
The symptoms are influenza-like and include fever,
malaise, myalgia, headache, diarrhea and shivering
(rigors).

• Fever is most frequently reported symptom;
cough (initially dry), shortness of breath and
diarrhea are present in the first and second week
of illness.
• Severe cases often evolve rapidly, progressing to
respiratory distress and requiring intensive care.
• The incubation period ranges between 3 and 10
days. Some days later, pneumonia may be
manifested, which in some case progresses to
fatal respiratory failure.

• Hand-washing with soap and water, or use of
alcohol-based hand sanitizer.
• Disinfection of surfaces of fomites to remove viruses.
• Avoiding contact with body fluids.
• Washing the personal items of someone with SARS in
hot, soapy water. The items include eating utensils,
dishes, bedding, etc.Keeping children with symptoms
at home. Do not send them to school.
• Simple hygiene measures.
• Isolating one-self as much as possible to minimize
the chances of transmission of the virus.
prevention

• Middle East Respiratory Syndrome (MERS) was
first identified in Saudi Arabia in 2012.
Causative Agent:
• It is a viral disease.
• MERS corona virus (MERS-CoV) is a zoonotic
virus transmitted between animals and
people. Humans are infected through direct or
indirect contact with infected dromedary
camels. It was identified in Middle East, Africa
and South Asia.
h) MERS:

• Clinical Presentation:
The clinical spectrum of MERS-CoV infection
ranges from no symptoms (asymptomatic) or
mild respiratory symptoms to severe acute
respiratory disease and death. A typical
presentation of the disease is fever, cough, and
shortness of breath. Pneumonia is a common
finding, but not always present. Gastro-
intestinal symptoms, including diarrhea have
been reported.

• Pharmacist should help in implementing following
preventive measures:
1. Wear a medical mask.
2. Wear eye protection (goggles or a face shield).
3. Wear a clean, non-sterile, long sleeved gown, and gloves.
4. Perform hand hygiene before and after contact with the
person and his/her surrounding and immediately after
removal of personal protective equipment (PPE).
5. Perform procedures in an adequately ventilated room.
6. Limit the number of persons present in the room to the
absolute minimum required for the person's care and
support.
prevention

Corona virus disease 2019 (COVID-19) was first identified
in Wuhan district of China in December 2019.9.
Causative agent :
It is a viral disease caused by a virus from corona virus
family. Genomically, COVID-19 virus is related to viruses
causing SARS and MERS. From December 2019, it has
become a pandemic influencing entire world population.
Most patients develop fever and/or symptoms of acute
respiratory illness (e.g. cough difficulty in breathing).
Symptoms are similar to that of SARS and MERS and they
may appear anytime from 2-14 days after exposure to the
virus.
i) Covid-19 :

• Pharmacist should help in implementing following
preventive measures:
• Avoid close contact with people who are sick.
• Avoid touching your eyes, nose and mouth with
unwashed hands.
• Wash your hands often with soap and water at least
for 20 seconds. Use an alcohol based sanitizer that
contains at least 60% alcohol if soap and water are
not available.
• Follow social distancing in public places.
• Use mask to avoid contamination by the virus.
prevention

• It is a rare disease in developed countries due
to routine vaccination of children. Three major
clinical types have been described:
1. Anteriornasal
2. Facial
3. Laryngeal.
In addition, other parts of the body like skin,
conjunctiva, vulva may be affected. The bacilli
multiply locally, usually in the throat and secrete
a powerful exotoxin.
j) Diptheria :

Causative Agent:
• It is caused by toxigenic strains of Corynebacterium
diphtheria.
• It is a gram positive, non motile organism.
• It has no invasive power, but produces a powerful
exotoxin.
• Three types of bacilli are differentiated: gravis, mitis
and intermidus.
• In general, gravis infections tends to be more severe.
• They are readily killed by heat & are sensitive to
penicillin.

Respiratory tract infections of diphtheria cause of
pharyngotonsillar, laryngotracheal, nasal and
combinations thereof. The symptoms are sore
throat, difficulty in swallowing and low grade fever.
In early stage, infected membrane may be whitish
and may wipe off easily. Patients with severe
disease may have marked oedema of the sub-
mandibular area and anterior portion of the neck,
giving a characteristic "bullnecked" appearance.
Tetaneous diphtheria is common in tropical areas. It
appears as a secondary infection of a previous skin
aberration or infection.

• The only effective control for diphtheria is by
active immunization with diphtheria toxoid for all
infants as early as possible.
• DPT vaccine should not be frozen. It should be
stored in a refrigerator at 4° 8° C.
• DPT vaccine can be safely and effectively
administered as early as 6 weeks after birth.
• It is advised that three doses of DPT vaccine
should be administered at the interval of 4
weeks.
prevention

• It is an acute infectious disease, usually of
young children. It is characterised by mild
fever and an irritating cough, gradually
becoming periodical with the characteristic of
"whoop" meaning loud crowing inspiration.
• It is for this specific sound, that it is termed as
whooping cough. The disease is also known as
pertussis.
k) Whooping cough : (pertussis)

The causative agent is Bordetella pertussis. The
organism occurs in smooth and rough phases,
capsulated and non-capsulated forms, and
elaborates an exotoxin and endotoxin. The
bacterium survives only for very short periods
outside the human body. It infects only man. It is
spread mainly by droplet infection and direct
contact. Each cough, sneeze or talk of a patient can
spray bacteria in air. Incubation period is of 7 - 14
days, but not more than 3 weeks.
Causative agent :

• The organism multiplies on the surface
epithelium of the respiratory tract and causes
inflammation and necrosis of the mucosa leading
to secondary bacterial invasion. Three stages of
the disease have been described:
(a) Catarrhal stage: lasting for about 10 days.
(b) Paroxysmal stage: lasting for 2 - 4 weeks, and
(c) Convalescent stage: lasting for 1 - 2 weeks.
The illness generally lasts for 6 - 8 weeks. The main
complications of whooping cough are bronchoitis,
bronchopneumonia and bronchiectasis.

Active immunization by DPT vaccine is the
effective way of controlling pertussis. If pertussis
is prevalent in the community, immunization can
be started at the age of one month. The
contraindications to pertussis vaccination are a
strong family history of epilepsy, convulsions or
similar CNS disorders.
prevention

Meningococcal meningitis or cerebrospinal fever
is an acute communicable disease.
l) Meningitis :

• The disease is caused by Heamophilus
meningitidis.
• The organism is found in the nasopharynx.
• The disease is spread by droplet infection.
• Incubation period is usually 3 to 4 days, but
vary from 2 to 10 days.
Causative agent :

• It begins with intense vomiting & stiff neck &
progresses to coma within a few hours.
• Treatment with antibiotics can save the lives
of 95% of patients provided, It is started in
first two days of illness.
• Improved housing & prevention of
overcrowding are the long term measures to
prevent the disease.
• Penicillin is drug of choice.
Role of pharmacist in education & prevention

• Acute respiratory infections (ARI) may cause
inflammation of the respiratory tract anywhere from
nose to alveoli, with a wide range of combination of
symptoms and signs.
• ARIS are further subclassified as Upper (AURI) and
'Lower (ALRI) depending on the site of infection.
• AURI include common cold, pharyngitis and otitis
media; while ALRI include epiglottitis, laryngitis,
laryngotrachieitis, bronchitis, bronchiolitis, and
pneumonia.
• In developing countries, measles and whooping
cough are most important ARIS.
m) Acute Respiratory Infections :

• Study from textbook.
Causative agent :
• Duration of infection is of importance
in the treatment.
• Symptoms like existence of fever,
history of convulsions, irregular
breathing and history of the child
turning blue help in deciding
seriousness of the disease.

• Preventive measures include improved living
conditions, better nutrition and reduction of
smoke in households.
• Good ventilation is an important point which
pharmacists have to emphasize.
• Limiting exposure of mother and children to
choolahs with smoke, especially in rural areas
is an important measure to control
environmental pollution.
prevention

• The disease primarily affects the lungs.
• It also affects intestine, meninges, lymph
glands, bones & joints.
• It is caused by Mycobacterium tuberculosis.
• It is transmitted by droplet nuclei.
• Droplet nuclei are generated by sputum
positive patients with pulmonary tuberculosis.
• Incubation period 3- 6 weeks.
n) Tuberculosis:

• Mycobacterium tuberculosis can infect many
organs of human body.
• It is presented from cough, weight loss, lack of
appetite, fever, sweating in night, fatigue,
chest pain.
• In severe cases blood may appear in vomit.
• It may infect nervous system leading to
tuberculous meningitis.

prevention
• The social factors propagating the disease include
poor quality of life, poor housing, overcrowding,
population explosion, under nutrition, lack of
education, large families, early marriages & lack
of awareness about cause of illness.
Special features:
• BCG vaccine (bacillus calmette gurein)
• It is administered intradermally either at birth or
at six week of age.
• The duration of protection is 15-20 years.

Treatment :
• The treatment is provided in 3- categories
1. Category 1
2. Category 2
3. Category 3
five drugs are commonly used for the treatment of TB
1. Isoniazide
2. Rifampicin
3. Ethambutol
4. Pyrazinamide
5. Streptomycin

o) Ebola:
• Ebola also known as Ebola virus disease (EVD)
or Ebola hemorrhagic fever (EHF).
• Caused by ebola virus.
• Ebola virus are 80nm in width & may be as
long as 14000 nm.
• It may appear in ‘U’ or a ‘6’ shape.
Causative agent :

• Signs & symptoms start between 2 days & 3
weeks after contracting the virus with fever,
sore throat, muscular pain & headaches.
• Vomiting, diarrhoea & rash usually follow
along with decreased function of liver &
kidneys.
• Some people begin to bleed both internally &
externally.
• Risk factor of death killing 25-90%.

Preventive Measures & Role Of
Pharmacist:
• Spreads through direct contact with body
fluids, such as blood.
• It also include protective clothing & washing
hands when around a person with the disease.
• This includes either oral rehydration therapy
or giving intravenous fluids.

II. Intestinal Infections
1. Poliomyelitis:
Poliomyelitis is an exclusively human disease & the
only source of virus is man.
Causative agent:
• The causative agent is polio virus which has 3-
serotypes: 1,2,3.
• It can survive for longer period in external
environments.
• It can live in water for 4 months and in faeces for
6 months. Thus, it is well adapted for faecal-oral
route of transmission.
• The virus is rapidly inactivated by pasteurization.

• An acute illness of childhood is characterized
by fever, headache, stiffness of neck, back &
moderately increased cells & proteins of the
spinal fluid.
• The incubation period is on an average about
10 days but may range from 4 days to 4 weeks.

1. Immunization
a) Inactivated polio vaccine (IPV) Salk
b) Oral polio vaccine (OPV) Sabin
2. Isolation of the patient
3. Supply of safe drinking water.
4. Improvement in personal hygiene.
prevention

2. Viral Hepatitis:
• Infection of the liver by any of the viruses.
• A,B,C,D,E&G varities are known as
HAV,HBV,HCV,HEV &HGV resp..
• Only 2- varities are discussed here
a) HAV:
It is an acute infection, previously termed as
infectious hepatitis or epidemic jaundice.

Causative agent:
• Hepatitis A virus.
• It is an enterovirus type, belonging to
Picornaviridiae family.
• The transmission may be faecal, oral,
parenteral route.
• The incubation period is of 15 to 45 days.

• Non-specific symptoms like fever, chills,
headache, fatigue, generalized weakness,
aches and pains are followed by anorexia,
nausea, vomiting, dark urine and jaundice.
• The mortality is only 0.1%, but the patients
may be incapacitated for many weeks.

• Maintaining personal & community hygiene.
• Inactivated or live attenuated vaccines.
b) HBV:
It is an acute systemic infection, formerly known as
serum hepatitis.
Causative agent:
• Hepatitis B virus.
• It is transmitted by parenteral route.
• Incubation period is 6 weeks to 6 months.
• It appears in the serum during incubation period.
• Biochemical evidence of hepatic damage or the
onset of jaundice, hence it has diagnostic
significance.

• It is an acute self-limiting infection, which may be
subclinical or symptomatic.
• In 5 to 15% of cases, the infection fails to resolve
and the affected individuals work as carriers.
• Persistent HBV infection may cause progressive
liver disease including chronic active hepatitis
and hepatocellular carcinoma.
• All classical symptoms of jaundice including lack
of appetite, generalized weakness, yellow
colouration of eyes and skin are observed.

• A vaccine is available as an intramuscular
injection.
• It is an acute diarrhoeal disease.
• Majority of infections are mild or
symptomatic.
prevention
3. Cholera:

• The causative agent is Vibrio Cholera.
• The organism is killed in 30 min by heating at
56 0C.
• They remain in ice for 4-6 weeks or longer.
• They are easily killed by disinfectants.
• Incubation period is from few hours to 5 days.
Causative agent:

• Typical symptoms are effortless watery
diarrhoea followed by vomitting, rapid
dehydration, muscular cramps & supression of
urine.
• The patient become restless & complains of
intense thirst with cramps in legs & abdomen.
• If untreated, death may occur at this stage
due to severe dehydration.

• Rehydration of the patient is the most important
therapy.
• If dehydration is mild, then oral rehydration with
chloride salts of sodium & potassium With sugar
is suggested.
• The pharmacist should emphasize on
1. The effectiveness & simplicity of oral
rehydration therapy
2. The benefits of early reporting for prompt
treatment.
3. Food hygiene practices.
4. The benefit of cooked,hot food & safe water.
prevention

• Diarrhoea lasting for 3 weeks or more are
called chronic, otherwise it is termed as acute.
• It is almost universally infectious in origin.
• Study from books.
All the organism lead to common clinical
presentation of diarrhoea of varying intensity or
duration.
4. Acute Diarrhoeal Diseases:
Causative agent:

• Following preventive stratergies should be
emhasized by pharmacist.
1. Sanitation:
• Improve food & domestic hygiene.
• Improved water supply.
• Maintain personal hygiene.
2. Health education:
• Environmental sanitation measures require
educational support.
prevention

3. Immunization:
• Immunization against measles is a potential
intervention for diarrhoea control
• Measles vaccine prevent upto 25% of
Diarrhoeal deaths in children under 5 yrs of
age.
From 1978, government of India has started
Diarrhoeal Disease Control program

• Includes both typhoid & paratyphoid fever.
Causative agent:
• Causative agent is salmonella typhi.
• The primary sources of infection are faeces &
urine of patients & carriers.
• The secondary source of infection is
contaminated water, food, fingers & files.
• Incubation period 10-14 days.but it may be as
short as 3 days & as long as 3 weeks.
5. Typhoid:

• Typical continuous fever for 2 to 3 weeks, relative to
bradycardia with involvement of lymphoid tissues &
considerable constitutional symptoms.
3-defence against typhoid fever
1. Control of reservoir:
• Carriers are ultimate sources of typhoid fever.
• Their identification & treatment is one of the
effective ways of controlling typhoid fever.
prevention:

2. Control of Sanitation:
Protection & purification of drinking water
supplies, improvement of basic sanitation,&
promotion of food hygiene are essential
measures for limiting transmissions.
3. Immunization:
-Monovalent anti-typhoid vaccine.
-Bivalent anti-typhoid vaccine.
-TAB vaccine.

6.Food Poisoning:
• It is an acute gastro-enteritis caused by
ingestion of food or drink contaminated with
either living bacteria or their toxins or
inorganic chemicals & poisons derived from
plant & animals.
It is of 2-types
1. Non bacterial: Caused by chemicals such as
arsenic, certain plants & sea foods.
2. Bacterial: caused by ingestion of food
contaminated by living bacteria or their
toxins.

Following causative agents are known:
1. Chemicals like fertilizers, pesticides, salts of toxic
metals.
2. One of the following microorganism:
• Salmonella typhimurium, salmonella enteritidis
• Staphylococcus aureus
• Clostridium botulism
• Clostridium perfringens (welchii)Bacillus Cereus
Causative agent:

• The clinical presentation depends on causative
agents. Salmonella food poisoning causes acute
enteritis and colitis. The onset is sudden with
chills, fever, nausea, vomiting and profused
diarrhoea which usually lasts for 2-3 days.
• Staphylococcus poisoning is manifested by
sudden onset of vomiting, abdominal and
diarrhoea. In severe cases, blood and mucus may
appear. Death is uncommon. cramps

3-preventive measures are suggest:
1. Food Sanitation:
- The food free of bacteria/ viral contamination.
- This is of special importance in case of meat of
animals.
- To ensure that food handlers should not
suffering from infected wounds, boils, diarrhoea,
dysentry, throat infection.
- Sanitization of all utensils & equipment should
be ensured.
- Food premises free from rats, mice, flies & dust.
prevention

2. Refrigeration:
- Food should not be left in warm pantries.
- Food should be kept in cold storage to prevent
bacterial multiplication & toxin production.
- When it is held in 10-490C then bacterial
growth is very fast so it is held at 40c to avoid
bacterial growth.
3. Surveillance:
food samples suggested to laboratory analysis.

7.Amoebiasis :
Causative agent:
The causative agent is Entamoeba histolytica.
It exist in 2-forms
1. Vegetative (trophozite):
Trophozites stay in colon whether they multiply &
encyst.
2. Cystic:
These are formed under adverse environmental
condition.

• The clinical symptoms include mild abdominal
discomfort & diarrhoea or dysentry.
• Extra intestinal amoebiasis includes
involvement of liver abscess, lungs, brain,
spleen, skin etc.

prevention
• The primary measures include limiting
contamination of water, food , vegetables &
fruits with human faeces.
The other actions includes:
1.Sanitation
2. Water supply
3.Food hygiene
4. Health education

8.Worm Infestations :
I. Hookworm :
3-types of hookworms are responsible for
intestinal infection.

1. Ascaris :
Causative agent:
- Ascaris lumbricoides lives in lumen of small
intestine.
- They become inactive in 2-3 week
- The embryonated eggs hatch in the small
intestine producing larvae.
- The larvae penetrate the gut wall & carried to
the liver & then to lungs via blood stream.
- In the lungs the mould twice.
- Then they migrate to bronchioles & to the
trachea.
- The incubation is about 2 months.

• The symptoms include nausea, abdominal
pain & cough.
• Live worms are passed in the stool or
vomitted.
• Occasionaaly they produce intestinal
obstruction.

prevention
• There are 2-types of preventive measures
1. Primary prevention:
- It is most effective interrupting transmission.
- Sanitary disposal of human excreta to prevent or
reduce faecal contamination of the soil,
provision of safe drinking water, food hygiene &
health education.
2. Secondary prevention:
it includes use of following drugs
Piperazine,mebendazole,levamisole,pyrantal.

2. Ancylostoma :
Causative agent:
-The infection caused by Ancylostoma
duodenale or Necator americanus.
-They may occur as single or mixed infection in
same individual.
- Adult worms live in the small intestine, mainly
jejunum where they attach to the villi.
- Adult hookworms are capable of surviving for
an average 1-4 years.

• Hookworm infection causes chronic blood loss &
loss of body’s iron leads to iron deficiency
anaemia.
• If preganant mother infected then the child also
infected results into low birth weight babies,
abortion etc.
• In adults, it leads to diminished capacity for
sustained hard work.
• It also cause loss of blood plasma leading to
hypoalbuminemia,.

prevention
• It involve 4 approaches
1. Sanitary disposal of faeces
2. Chemotherapy
Albendazole, mebendazole, levamisole,
pyrantal
3. Treatment of anaemia
4. Health education

II. Guineaworm:
• It is a vector borne parasitic disease, mainly of
sub-cutaneous tissues.
• It is also termed as dracunculiasis.
Causative agent:
- The causative agent is Dracunculus medinesis.
- The adult parasite inhibits sub cutaneous
tissue mainly of the legs, it may also affect
head & neck.
- The larve may remain active in water for 3-6
days.

• Blisters on the skin of the infected person’s lower
limbs.
Preventive measures include
• Provision of safe drinking water.
• Control of cyclops.
• Health education related to boiling or sieving
drinking water & prevention of water
contamination to infected persons.
• Treatment :Niridazole,Metronidazole,mebedazole
etc.

Arthropod-Borne Infections
1. Dengue :
- Dengue is a viral disease belonging to the group of
arboviruses, capable of infecting humans & causing
the disease.
Causative agent:
The arbovirus is transmitted through vector mosquitoes
Aedes aegypti and Aedes albopictus. The dengue virus
occurs in four serotypes: 1, 2, 3 and 4. Fever can occur
epidemically or endemically. Epidemics may be
explosive and often start during the rainy season. The
reservoir of infection is both man and mosquito. The
transmission cycle is "Man- mosquito - Man".

• Aedes mosquito becomes infective by feeding
on a patient from the day before onset to the
5th day of illness. This is termed as viraemia
stage. After an extrinsic incubation period of 8
- 10 days, the mosquito becomes infective,
and is able to transmit the infection. Once the
mosquito becomes infective, it remains so for
the entire life. The illness is characterized by
an incubation period of 3 - 10 days; most
commonly 5 - 6 days.

Infection may be asymptomatic or may lead to
one of the following manifestations:
• Classical dengue fever:
The onset of symptoms is sudden with chills &
high fever, intense headache, muscle & joint pain.
• Dengue haemorrhagic fever without shock
• Dengue haemorrhagic fever with shock
- It is a severe form of dengue fever, caused by
infection with more than one dengue fever.
- Incubation period is of 4-6 weeks.
- high fever accompanied by facial flushing &
headache.

Dengue shock syndrome :
• It has all clinical manifestations of DHF along
with shock represented by rapid & weak pulse
with narrowing of pulse pressure (20 mm Hg
or less ) or hypotension, with presence of cold,
clammy skin & restlessness.

Role of pharmacist in Education &
prevention:
• Mosquito control: the most common action is
to keep water flowing & avoid accumulation of
unhygienic stagnant water.
• Vaccines: no vaccine is available.
• Other measures: isolation under bed nets
during first few days can provide individual
protection against mosquito.

2.Malaria
• It is a protozoal disease caused by the infection
with a parasite.
Causative agent:
• The causative agent is plasmodium vivax,
plasmodium falciprum, plasmodium malariae &
plasmodium ovale.
• The malarial parasite undergoes 2-cycles of
development.
1. Human cycle
2. Mosquito cycle

• Man is the intermediate host & mosquito is
the definitive host.
• Malaria is transmitted by the bite of certain
species of infected, female anopheles
mosquitoes.
• The mosquito is not infective unless the
sporozytes are present in its salivary gland.
• Incubation period varies with the species of
parasite. It is 12 (9-14 ) days for P.Falciparum.

• A typical malarial attack comprises 3-stages
1. Cold stage:
The onset is with headache, nausea and chilly
sensation followed in an hour or so by rigors.
Headache is often severe and commonly there is
vomiting. In early part of the stage, skin feels
cold; later it becomes hot. Parasites are usually
demonstrated in blood. The pulse is rapid and
may be weak. This stage lasts for 4 to 1 hour.

2. Hot stage:
• The temp rises rapidly to 39-41°C.
• The pulse is full & respiration is rapid.
• This stage is lasts for 2-6 hrs.
3. Sweating stage:
• Fever comes down with profuse sweating.
• The temp drops rapidly to normal &skin is cool
& moist.
• This stage is lasts for 2-4 hrs.

Role of pharmacist in education and
prevention
• There are 2-different approaches to malaria
control:
1. The management of malaria cases in the
community:
a) Presumptive Treatment: It means that all
cases are assumed to be due to malaria. All
surveillance workers are administered a
single dose of chloroquine phosphate in
600mg doses.

b) Radical treatment: it changes with the type of
infection
Short term chemoprophylaxis is done with
doxycycline 100 mg daily &
Long term chemoprophylaxis is done with
mefloquine 5mg/kg weekly.
2. There are 3 stratergies for the control of
disease
Vector control measures are the primary
weapons to control malaria in endemic areas
These efforts are sub divided into 2 types

i) Anti-adult measures:
• It involves spraying insecticides like DDT,
malathion, fenitrothion.
• Individual protection with the use of mosquito
repellent,protective clothing,bed nets
impregnated with insecticides, mosquito coils are
suggested.
• ii) Anti-larval measures:
• Few larvicides like temphos are suggested.
National malaria eradication programme is being
implemented by Government of India.
Vaccine against malaria is under clinical
development.

3.Filariasis:
• The commonly used term is Lymphatic
filariasis.
• It covers infection caused by 3-closely related
nematode worms.
• All infection are transmitted by the bites of
infected mosquitoes.

Causative agent:
• The commonly infective nematodes are Wucheria
bancrofti, Brugia malayi & Brugia timori.
• All the parasites have similar lifecycles in man.
• Adult worms live in lymphatic vessels of infected
individuals.
• Incidence of the disease depends on man-
mosquito contact.
• The incubation period is 8 to 16 months from the
invasion of the infected larvae.

• The clinical presentation can be divided into two
distinct phases:
1. Lymphatic filariasis:
In this phase,4-stages have been described
i). Asymptomatic amicrofilaria:
In all endemic areas a proportion of population
neither have microfilaria in their body, nor do they
show clinical manifestation of the disease, probably
because of immunological defence. This group
consists of asymptomatic amicrofilaria.

(ii) Asymptomatic microfilaria :
Some individuals in the endemic areas do show
microfilaria in their body, but they continue to be
without any symptoms, may be for months or even
years. These carriers are source of infection in the
community. Collection of blood samples during
night can show presence of the infective organisms.
(iii) Stage of acute manifestations :
In the infected patients, during first few months or
even years, there are recurrent episodes of acute
inflammation in lymph glands and vessels. The
clinical manifestations include filarial fever,
lymphangitis, lymphoedema, of various parts of the
body and of epididymoorchitis in the male.

(iv) Stage of Chronic Obstructive Lesions :
The chronic stage usually develops 10 - 15 years
after the first acute attack. This phase is due to
fibrosis and obstruction of lymphatic vessels causing
permanent structural changes. Elephantiasis is the
primary symptom in chronic cases affecting legs,
scrotum, arms, penis, vulva and breasts.
2. Occult Filariasis:
The occult filariasis refers to filarial infections in
which the classical manifestations of the disease are
not present and the microfilaria is not found in the
blood. It is believed to result from a hypersensitivity
reaction to filarial antigens derived from microfilaria.
The best known example is topical pulmonary
eosinophilia.

prevention:
2- kinds of preventive measures are suggested:
1. Chemotherapy:
Diethylcarbamazepine citrate & Ivermectin.
2. Vector control:
The most important element in vector control is the
reduction of target mosquito population in order to
stop or reduce transmission quickly.
Control of vector is done by 3 following measures

1. Anti-larval measures:
• Elimination of the breeding places of mosquitoes
by providing adequate sanitation & underground
waste water disposal system.
• Chemical control by using mosquito larvicidal
oil,pyrosone oil,temphos or phenithion is
suggested.
2. Anti-adult measures: since mosquitoes have
shown resistance to few synthetic pesticides,
pyrethrum as a space spray is suggested.
3. Personal prophylaxis: the most effective
preventive measure is avoiding mosquito bites by
using mosquito nets.

4. Chickungunya:
• It is a viral disease that is transmitted to people
by mosquitoes.
• The virus is passed to humans by two species of
mosquito of the genus Aedes: A.albopictus & A.
aegypti.
• Animal reservoirs of the virus include
monkeys,birds, cattle & rodents.
Causative agent:
It is caused by chickungunia virus. It is an alphavirus
with a positive sense single stranded RNA genome
of about 11.6 kb.

• It is usually starts suddenly with fever,chills,
headache, nausea, vomitting, joint pain & rash.
• This refers to the contorted posture of patients
who are afflicted with the severe joint pain
(arthritis).
• While recovery of chickungunya refers to
analgesic (pain medication) & long term anti-
inflammatory therapy.

prevention:
• There is neither chickungunya virus vaccine
nor drugs are available to cure the infection.
• Use of mosquito repellants on skin & clothing.
• When indoors, stay in well-screened areas.
Use bed nets.
• When working outdoors wear long sleeved
shirts & long pants to avoid mosquito bite.

• Following things are specifically recommended for
mosquito control:
a) Source reduction method:
i) By elimination of all potential vector breeding places
near the domestic or peridomestic areas.
ii) Not allowing storage of water for more than a week.
iii) Straining of stored water by using a clean cloth once
a week to remove the mosquito larve from water &
water can be reused.
b) Use of larvicides:
1. Temphos can be used once a week at a dose of 1
ppm.
2. Pyrethrum extract can be sprayed in rooms to kill the
adult mosquitoes.

1. Trachoma:
It is chronic infectious disease.
Causative agent:
The causative agent is Chlamydia trachomatis. It has
eleven known serotypes. It primarily causes
conjunctivitis. Eye to eye transmission is possible.
Contamination with ocular discharges of infected
persons fomites like infected fingers, towels, kajal or
surma play a role in spreading the infection. It tends to
be a familial disease. The incubation period is 5 - 12
days.

The infection leads to inflammation. The
inflammation may undergo spontaneous
resolution or may progress to conjunctival
scarring which can cause inward deviation of
eye lashes, termed as trichiasis or of the lid
margin termed as entropion. The aberration of
cornea by eye lashes frequently results in
corneal ulceration, followed by scarring and
visual loss. Hence, the disease is termed as
"blinding trachoma".

Role of Pharmacist in Education and
Prevention:
Chemotherapy is one of the effective
intervention. 1% ophthalmic ointment or oily
suspension of tetracycline is suggested.
Alternatively, Erythromycin and Rifampicin is
recommended. In long run most of the antibiotic
treatment should be carried out by affected
population itself; hence education of population is
needed.

2. Tetanus
It is an acute disease induced by exotoxin of the infective
organism.
Causative Agent:
The causative agent is Clostridium tetani. It is a gram-
positive, anaerobic, spore bearing organism. The spores
are terminal and give the organism a drum stick
appearance. The spores are highly resistant to a number of
injurious agents, including boiling, phenol, cresol and
autoclaving for 15 minutes at 120 °C. They germinate
under anaerobic conditions and produce a potent
exotoxin, called tetanospasmin. The spores are best
destroyed by steam under pressure at 120 °C for 20
minutes or by y radiation.

• It is characterized by muscular rigidity which
persists throughout illness. It is accompanied
by periodic spasms of voluntary muscles,
especially the "lock-jaw" muscle, the facial
muscles, the muscles of the back and neck,
and those of lower limbs and abdomen. The
mortality is very high, varying from 40-80 %.

Role of Pharmacist in Education and Prevention:
Tetanus is best prevented by active immunization with
tetanus toxoid. It stimulates the production of protective
antitoxin. Two preparations are available for active
immunization.
1. Combined vaccine (DPT): Under expanded immunization
programme it is a vaccine against Diptheria, Pertusis and
Tetanus. Combined
2. Monovalent vaccines:
(i) Plain or fluid (formal) toxoid: It contains detoxified form of
only Clostridium.
(ii) Tetanus vaccine, adsorbed (PTAP, APT): Purified tetanus
toxoid (adsorbed) has largely replaced plain toxoid because it
stimulates a higher and long lasting immunity response than

Introduction To Microbiology & Common Microorganisms.pptx

Introduction To Microbiology & Common Microorganisms.pptx

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