Download Typhoid fever

Typhoid fever
Presented by Abhinay Sharma Bhugoo
What is typhoid fever?
Typhoid fever is an acute illness
associated with fever that is most
often caused by Salmonella typhi
bacteria. It is a general infection
involving primarily the lymphoid
tissues (Peyer’s Patches)
What is typhoid fever?
 Typhoid fever is a bacterial infection of the
intestinal tract and occasionally the bloodstream.
 The disease rarely occurs in developed countries.
It is most commonly seen in countries with poor
sanitary conditions and contaminated water
supplies.
 Most of the cases are acquired during foreign
travel to underdeveloped countries.
What is typhoid fever?
Outbreaks are rare.
The germ that causes typhoid is a unique
human strain of Salmonella called Salmonella
typhi.
Epidemiology: Incidence
 World: 17 million cases per year
 U.S.: 400 cases per year (70% in travelers)
 PHILIPPINES
(Nov 2006) 478 in Agusan del Sur.
(May 2004) 292 in Bacolod City
Typhoid fevers are prevalent in
many regions in the World
Who gets typhoid fever?
Anyone can get typhoid fever but the greatest
risk exists to travelers visiting countries
where the disease is common.
Occasionally, local cases can be traced to
exposure to a person who is a chronic carrier.
Infants and persons over 60 usually have the
severest cases.
Systemic bacterial infection (Enteric Fever)
1.Salmonella typhi (Typhoid fever)
 Most common and more severe form
2. Salmonella paratyphi A, B and C(Paratyphoid
fever)
 Much more mild than Typhoid fever
Transmission
Ingestion of contaminated food
Typhoid germs are passed in the feces and, to
some extent, the urine of infected people.
The germs are spread by eating or drinking
water or foods contaminated by feces from
the infected individual.
Etiology
 Caused by Salmonella typhi (causative
agent) which is harboured in human
excreta (source of typhoid fever)
 The causative agent is a gram-negative () motile and nonsporeforming bacillus
 The organism is pathogenic only for man
Source of Infection
Since there’s NO animal host
The source of infection are either:
1. PATIENT: suffering from a disease including mild
and ambulatory cases which excretes bacilli in
the feces and urine for about one month.
Infected vomit and pus abscesses are also
source of infection
Sources of Infection
2. Carriers : 3 types:
a) Convalescent carrier – passes bacilli in the
excreta 6 months after an attack of typhoid.
b) Chronic faecal carrier - passes bacilli in the
excreta 1 year after an attack of typhoid
c) Chronic Urinary carrier - the renal pelvis is
infected and bacilli pass through the urine
Mode of Transmission
 Shell fish contaminated with infected water
 Infected milk and ice cream made with infected
milk products
 Salads, which was contaminated with infected
water
 Ice
 Contaminated meat and poultry
 Flies and maggots that carries bacteria can be
considered as vectors
 Asymptomatic carriers
Risk factors
Travel to developing country or refugee
camp
Highly dense living conditions
Vi antigen
O antigen
H antigen
 It is identified by biochemical reactions and serological grouping
and typing of its antigens: O(somatic - a warning or signal of
danger.), H(flagellar – extremity of a flagellum), and
Vi(carbohydrate envelope).
Pathophysiology
Salmonella Typhi
survives the acidity of the stomach
invades the Peyer’s Patches of the intestinal wall
macrophages (Peyer’s Patches)
the bacteria is within the macrophages and survives
bacteria spreads via the lymphatics while inside the
macrophages
Pathophysiology
access to Reticuloendothelial system, liver, spleen,
gallbladder and bone marrow
First week: elevation of the body temperature
Second week: abdominal pain, spleen enlargement and
rose spots
Third week: necrosis of the Peyer’s Patches
leads to perforation, bleeding
and, if left untreated, death is imminent
What are the symptoms?
 The symptoms may occur rapidly,
particularly in children.
 However, in adults, they usually come on
slowly
Relapses are common.
Fatalities are less than 1% with antibiotic
treatment.
Symptoms generally appear one to three
weeks after exposure.
Symptoms:
 Incubation (first 7-14 days after ingestion)
Usually asymptomatic
 Diarrhea may occur
 Active infection
 Severe Headache
 Generalized Abdominal Pain
 Anorexia
 Constipation more common than Diarrhea
 Fever [usually higher in the evening]
 Intermittent Fever initially
 Sustained Fever to high temperatures later
Signs:
Relative bradycardia
Pulse-Temperature Dissociation (uncommon)
Rose Spots (Pathognomonic, present in 25%
of cases)
Blanching pink macular spots 2-3 mm over trunk
Rashes in Typhoid
 Rose spots usually occurs
between the 7th and 10th
days of illness. Spots last
up to 3-4 days, then
disappears completely.
The spots may continue
to appear for another 1 to
2 weeks.
› Rose spots are due to
clumps of bacteria
surrounded by small
round cells in the skin.
› 12 in typhoid, much
more numerous in
paratyphoid.
Events in a Typical typhoid Fever
The typical ‘FACE OF TYPHOID’.
This diagnosis is often be made at the bedside
before the patient is being examined
Cheeks are usually flushed and the
eyes bright during the first week of
illness. In the second and third
weeks the expression becomes dull,
the pupils dilated, and the skin and
lips are dry
A patient shows a rather indefinite
state on admission that can best be
described as ‘toxic”.
Pathological Changes
 Peyer’s Patches of the ileum changes and vary
from hyperplasia and ulceration to frank
ulceration and typhoid perforation
 Liver may be enlarged with fatty changes
 The skin may show changes with the collection
of bacilli, which causes the ‘Rose Spots’
Pathological Changes
 Cholecystitis may lead to formation of infected
gall stones in the gall bladder
› These may be asymptomatic and may be potent source
of infection in the typhoid carrier, sometimes many
years after the initial infection
 The spleen is enlarged and soft
 The mesenteric gland is enlarged
› peritoneum responsible for connecting
the jejunum and ileum (parts of the small intestine) to
the back wall of the abdomen.
Pathological Changes
 The kidneys shows cloudy swelling and this may result to
albuminuria
 Bronchitis is common in typhoid fever, and diffuse rales are
usual findings on clinical auscultation of the lungs in
typhoid fever
 In severe case of typhoid fever, the heart may be enlarged
and affected by the fatty degeneration
 Finally, thrombosis of the deep vein may occur, particularly
in the lower limb, and lead to a fatal pulmonary embolus
Pathological Changes
Pathological Changes
Complications:
(occurs in 10-15% of cases)
Gastrointestinal Bleeding (2-10% of cases)
Bowel perforation
Typhoid encephalopathy
For how long can an infected person
carry the typhoid germ?
The carrier stage varies from a number of
days to years.
Only about 3% of cases go on to become
lifelong carriers of the germ and
This tends to occur more often in adults than
in children.
Diagnosis
 Good history taking
 Clinical picture : Clinical Signs
 Culture of:
›
›
›
›
Bone marrow
Blood (1st week)
Duodenal Bile
Stool and Urine (3rd week)
 Serology : Widal agglutination reaction. (2nd
week)
 Laboratory study
 Detection of bacterial DNA
Immune Response in Typhoid
Typhidot test
Typhidot test (if illness is 4 days or
longer)
Interpretation:
Ig M
Ig G
(+)
(- ) Acute infection
(+)
(+) Recent infection
(- )
(+) Equivocal: Past
infection or acute
infection
Should infected people be
isolated?
Because the germ is passed in the feces of infected people, only
people with active diarrhea who are unable to control their bowel
habits (infants, certain handicapped individuals) should be
isolated.
Most infected people may return to work or school when they
have recovered, provided that they carefully wash hands after
toilet visits.
Children in daycare, health care workers, and persons in other
sensitive settings must obtain the approval of the local or state
health department before returning to their routine activities.
Food handlers may not return to work until three consecutive
negative stool cultures are confirmed.
Is there a vaccine for
typhoid?
A vaccine is available
but is generally reserved for people traveling
to underdeveloped countries where significant
exposure may occur. Strict attention to food
and water precautions while traveling to such
countries is the most effective preventive
method.
Treatment
 BED REST:
 Hospitalization for low classes of people because of bad
hygienic measures
 FULL NUTRITION
 Soft diet is recommended
 ANTIBIOTICS
 VITAMINS
 Especially water soluble (B&C)
Management: Antibiotics
Specific antibiotics are often used to treat cases
of typhoid.

Antibiotic Resistance is increasing

First-Line: Fluoroquinolones

Alternative antibiotics (resistance is common)

Chloramphenicol

Amoxicillin

Trimethoprim-Sulfamethoxazole (Septra)
Prevention
 Choose foods processed for safety
 Prepare food carefully
 Foods prepared by others (avoid if possible)
 Keep food contact surfaces clean (3 wash cycle)
 Eat cooked food as soon as possible
 Maintain clean hands
 Steam or boil shellfish at least 10 minutes
 All milk and dairy products should be pasteurized
 Control fly populations
Mary Mallon
(September 23, 1869 – November 11, 1938)
Mary Mallon
(September 23, 1869 – November 11, 1938)
Also known as Typhoid Mary
was the first person in the United
States to be identified as a healthy
carrier of typhoid fever.
She seemed a healthy woman when a
health inspector knocked on her door
in 1907, yet she was the cause of
several typhoid outbreaks.
Mary Mallon
(September 23, 1869 – November 11, 1938)
 Since Mary was the first "healthy carrier" of typhoid
fever in the United States, she did not understand
how someone not sick could spread disease -- so she
tried to fight back.
 She was forcibly quarantined twice by public health
authorities and died in quarantine.
 Over the course of her career as a cook, she infected
47 people, three of whom died from the disease.
 It was also possible that she was born with the
disease, as her mother had typhoid fever during her
pregnancy.
Mary Mallon
(September 23, 1869 – November 11, 1938)
 Mary Mallon died on November 11, 1938 at
the age of 69
due to pneumonia (not typhoid), six years
after a stroke had left her paralyzed.
 However, an autopsy found evidence of live
typhoid bacteria in her gallbladder.
 Her body was cremated with burial in Saint
Raymond's Cemetery in the Bronx.
Thank you