Infectious diseases

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Exanthem subitu or
Roseola is an acute
disease of infants and
young children that is
characterized by high
fever followed by a rash
that appears on trunk,
limbs, neck and face
The disease is common in children 6
months to 2 years old. It is caused
by a virus, called human
herpesvirus 6 (HHV-6). It occurs
most often in the spring and fall. The
incubation period is 5 to 15 days. A
fever lasting 3 (sometimes up to 5)
days generally preceds the
appearance of the rash and may be
as high as 105 degrees Fahrenheit.
Febrile convulsions may occur when
the fever is high, especially when it
is on the way up. Roseola typically
begins with a high fever that
responds well to acetaminophen.
When the temperature is down the
infant or child may behave as if well.
Between the 2nd and 4th day the
fever falls dramatically and a rash
appears (often as the fever falls) on
the trunk and spreads to the limbs,
neck, and face. The rash lasts from a
few hours to a day.
Three day measles; German measles or
Rubella is an infectious
disease transmitted by the
rubella virus. The signs of
the disease are: swelling of
lymph nodes in the neck and
a skin rash which first
appears on the face and then
rapidly spreads to other
parts of the body. The
complications of rubella
include encephalitis and joint
pain. Infection with rubella
during pregnancy can cause
serious damage to the child,
including cataracts,
deafness, heart defects and
mental retardation.
There is no drug therapy for
rubella. However, the
disease can be prevented by
immunization.
The disease is caused by a virus that is spread through the air or by close
contact. It can also be transmitted to a fetus by a mother with an active
infection. The disease is usually mild and may even go unnoticed. Children
may have few symptoms, but adults may experience a prodrome (warning
symptom) of a fever, headache, malaise, runny nose, and inflamed eyes that
lasts from 1 to 5 days before the rash appears. A person can transmit the
disease from 1 week before the onset of the rash until 1 week after the rash
disappears. The disease is not as contagious as rubeola (measles),
therefore many people are not infected during childhood. Lifelong immunity
to the disease follows infection. Epidemics may occur at about 6- to 9-year
intervals. The risk factors are the unimmunized individuals.
The disease is potentially serious because of the ability to produce defects
in a developing fetus if the mother is infected during early pregnancy. As
many as 10 to 15% of women in their childbearing years are susceptible to
infection. Congenital rubella syndrome occurs in 25% or more of infants
born to women who acquired rubella during the first trimester ofpregnancy.
Defects are rare if the infection occurs after the 20th week of pregnancy. One
or more defects may occur in an infected fetus and include deafness,
cataracts,microcephaaly,mental retardation,congenital heart defects and
other defects. A miscarriage or stillbirth may occur.
Risk factors include lack of immunization and exposure to an active case of
rubella.
Rubella syndrome, or congenital rubella, is a group of physical
abnormalities that have developed in an infant as a result of maternal
infection and subsequent fetal infection with rubella virus. It is characterized
by rash at birth, low birth weight, small head size, heart abnormalities, visual
problems and bulging fontanelle.
Measles is an infectious
disease transmitted by
the measles virus. The
signs of the disease
are: fever, bronchitis,
conjunctivitis and a skin
rash which initially
appears in the mucous
membranes inside the
cheeks and can later
spread to the entire
body.
Complications of
measles include: middle
ear infection,
pneumonia, encephalitis
and appendicitis. There
is no drug therapy for
measles. However, the
disease can be
prevented by
immunization.
Rubeola, or measles, is caused by the
paramyxovirus. The infection is spread by
droplets from the nose, mouth or throat of an
infected person. The incubation period is 10 to
14 days before symptoms generally appear. An
immunity to the disease occurs after
vaccination, after active infection, and passive
immunity of an infant whose mother is immune
lasts most of the first year of life. Before
widespread immunization, measles was very
common during childhood so that 90% of the
population had been infected by age 20. Measles
cases have dropped by 99% in the U.S. and
Canada after widespread immunization.
Susceptible individuals are young infants as the
maternal antibody decreases, and those who
refuse immunization. Teenagers and young
adults who have not received a second
immunization are also susceptible.
Measles outbreaks still occur in the United States, usually among groups
that do not believe in immunizations or in areas where immunization levels
have fallen below the critical level. It is a fairly serious childhood infection
that is recognized by the rash), Koplik spots, red eyes and photophobia, and
coughing.
Koplik spots are seen with measles. They are small, white spots (often on an
reddened background) that occur on the inside of the cheeks early in the
course of measles may appear as irregular red spots with a minute, bluish
white center opposite molars 2 days before rash
Mumps is an infectious disease
transmitted by the mumps
virus. The signs of the disease
are: inflammation of the
parotid (salivary) gland
accompanied by a painful
swelling below the ear. The
complications of mumps include:
inflammation of the testes and
an elongated structure called
the epididymis (possibly causing
sterility in later life),
meningitis and pancreatitis.
There is no drug therapy for
mumps. However, the disease
can be prevented by
immunization.
Children between the ages of 2 and 12 are
most commonly infected, but the infection
can occur in other age groups. The
incubation period is usually 12 to 24 days.
The first shot is recommended at 1215 months. Because the first shot
may not provide adequate lifetime
immunity to some individuals, a
second MMR is recommended prior
to school entry at 4-6 years or prior
to entry into junior high at 11-13
years. Some states require a second
MMR at kindergarten entry
VACCINE INFORMATION
The MMR vaccine is a "3-in-1" vaccine
that protects against measles, mumps,
and rubella. Although single antigen
(individual) vaccines have been
developed for each component of the
MMR, they are not readily available and
usually used only for very specific
situations. An example of such a
situation would be if an outbreak of
either measles, mumps, or rubella was
occurring in a specific community and
public health officials deemed it
necessary to immunize infants 6 to 12
months old. Single antigen vaccines
might be used because they pose less
risk to children younger than the
recommended age of 12 months for the
MMR. For children 12 months or older
and adults, the risks of giving the single
antigen vaccine are presumed to be the
same as giving the MMR.
Chicken Pox or Varicella = A highly contagious, usually mild
childhood disease caused by the Herpes virus varicella-zoster virus,
which also causes herpes zoster (shingles)).
Chickenpox is a viral disease characterized by itching and a
skin rash with fluid-filled blisters that burst and form crusts.
The onset of the chickenpox rash may be preceded by a day
of mild fever and general malaise. The rash begins with a
few small reddish bumps (papules) that quickly fill with fluid
to form small blisters (vesicles). The vesicles appear in
"crops", small groupings, first on the trunk then spreading
to the extremities, face and scalp over a period of two to four
days. The rash may spread into the mouth and other internal
parts of the body. The vesicles break and a light brown scab
or crust forms over the top. This crust gradually darkens to a
dark brown before it finally falls off, usually within two
weeks of the onset of the illness. It is characteristic to have
more than one type of rash at the same time
Chickenpox seldom causes scarring, but when it does, the
scars most often occur around the eyes and consist of a
small depression. Chickenpox lesions can become infected,
usually from scratching and most frequently with
staphylococcus. These secondary infections may be severe
enough to require hospitalization.
Rash of
chickenpox
Prevention
Chickenpox is spread from person
to person by repiratory droplets, or
by contact with articles freshly
soiled by discharge from the
lesions. It is contagious two days
before the onset of the rash until six
days after the appearance of the first
lesions, or until all of the lesions are
crusted over. The incubation period
is 10 to 21 days. There is universal
susceptibility to the virus in those
not previously infected. Most
children have been infected with the
virus by the age of 10. After
infection, lifelong immunity against
recurrent infection is usually
present. However, a person with a
history of chickenpox may develop
shingles (herpes zoster) later in life.
Varicella zoster immune globulin (VZIG)
may modify the severity of the disease, or
prevent the disease if given within 96
hours after exposure to the virus. In
general, this is reserved for high-risk
individuals because the disease usually is
benign. High risk individuals are those
with no past history of chickenpox and
who have a condition (such as depressed
immune system, chemotherapy, AIDS,
leukemia, lymphoma or organ transplant)
and have been exposed to chickenpox.
Varicella vaccine is recommended
between the ages of 12 and 18 months.
(see immunization schedule) If a teenager
is not known to have had Chicken pox,
then blood can be drawn to see if he or
she is susceptable to the disease, and if
so the vaccine should be administered.
Varicella vaccine has become a
recommended childhood vaccine.
Treatment
General measures to relieve itching associated with skin lesions include cool
water soaks or compresses, and bathing with one cup of baking soda added to
a bathtub of lukewarm water. Topical preparations such as nonprescription
calamine lotion, antihistamines, or other lotions containing camphor, menthol
or phenol may be helpful. Fingernails should be trimmed to prevent
scratching, which may lead to a secondary infections. Infant’s hands may be
covered with a soft cotton or flannel mitten to prevent scratching (the hand
should never be restrained).
DO NOT USE ASPIRIN! To reduce fever, use acetaminophen instead of aspirin.
Aspirin use during a viral illness, particularly chickenpox, has been associated
with a risk of developing Reyes syndome. A sedative given at night may be
prescribed for sleep.
The prescription drug acyclovir has been approved by the FDA for use in treating the
symptoms of chicken pox in people over 2 years old. Although acyclovir usually is
reserved for teenagers, because the disease is more severe in that age group. The drug
should help reduce the severity of chickenpox symptoms, especially in older children
and teenagers if taken within 24 hours of the rash’s first appearance. It may also be
prescribed in severe cases or in people who areimmpunosuppressed. An alternative
antiviral agent is vidarabine.
Children should be kept home from school or day-care until all of the blisters have
broken and scabbed over, and they feel well enough to participate in normal activities.
Complications
Chickenpox is normally a mild
disease. But it can be serious
and lead to complications in
these high—risk groups:
•Newborns and infants
•Teenagers
•Adults
•Pregnant women
•People whose immune
systems are impaired by
disease or suppressed by
drugs
The most common
complication from chickenpox
is a bacterial infection of the
skin. The next most common
problems are pneumonia and
encephalitis (inflammation of
the brain), both of which can
be very serious if not treated.
Chickenpox early on in pregnancy can result in birth
defects such as limb deformities. The great threat to
the baby, though, is when the mother develops
chickenpox a week before birth. Then it can cause a
serious, life—threatening infection in the newborn. A
pregnant woman who's not immune to chickenpox
and has prolonged exposure to a person with the
disease should consult with her physician about the
risk to herself and her unborn child.
Anyone who has had chickenpox as a child is at risk
for a latent complication called shingles. After an
infection some of the varicella—zoster virus may
remain and hide in nerve cells. Many years later the
virus can reactivate and resurface as shingles — a
painful band of short—lived blisters. About one in
five adults who've had chickenpox experience
shingles, usually after age 50. Children can develop
shingles but do so less often than adults. Rarely, a
person with shingles can pass along the chickenpox
virus to others who aren't immune.
Shingles can lead to its own complication — a
condition in which the pain of shingles persists long
after the blisters disappear. This complication,
called postherpetic neuralgia, is not contagious.
Complications of Chicken pox
•Women who acquire chickenpox early in pregnancy are at risk for
congenital malformations in the fetus (rare).
•Newborns are at risk for severe infection if their mothers are not
immune. (They are considered one of the high risk group who should
receive VZIG.)
•Secondary infections of blisters (vesicles) with staphylococcus or
streptococcus bacteria may occur.
•Encephalitis occurs in less than 1 out of 1,000 cases and tends to
occur late in the disease or one to two weeks after the skin lesions
have healed.
•Reyes Syndrome,pneumonia,myocarditis, and transient arthritishave
also been reported as complications of chickenpox.
•Cerebellar atazia may appear during the convalescent phase or later.
Cerebellar ataxia is characterized by a very unsteady walk.
Fifth Disease or Parvovirus B19; Erythema infectiosum; Slapped cheek
Fifth disease is caused by the human parvovirus B19 agent. It occurs most often
during the spring with localized outbreaks in preschoolers or school-age children and
adolescents. It is spread by respiratory secretions and the duration of the illness is
usually five days. However, the rash may recur for several weeks and may be brought
on by exposure to sunlight, heat,exercise, fever, or emotional stress.
Erythema infectiosum usually begins with bright red cheeks producing a "slappedcheek" appearance. Following this, a rash appears on the extremities and trunk. The
rash fades centrally giving a lacy (reticulated) appearance to the rash. The rash fades
over a period of 1-2 weeks. This illness is seldom associated with fever.
Parvovirus B19 is thought to cause other disease manifestations. In healthy adults it
may be responsible for an infectious arthritis (particularly in women). In individuals
with AIDS (or other immunocompromised persons) it may produce a profound
anemia. This form of anemia is called 'transient aplastic crisis'.
The incidence of parvovirus B19 infection is unknown, but studies suggest that 40%
to 50% of adults have antibodies to the virus. This indicates a high degree of
infection, and also suggests that many infections go unnoticed.
Erythema infectiosum usually
begins with bright red cheeks
producing a "slapped-cheek"
appearance. Following this, a
rash appears on the
extremities and trunk. The
rash fades centrally giving a
lacy (reticulated) appearance
to the rash. The rash fades
over a period of 1-2 weeks.
This illness is seldom
associated with fever.
Poliomyelitis is a disease
transmitted by the polio
virus and characterized by
paralysis of the nerves in
the spinal cord.
The first signs of the
disease include: fever,
reddening of the throat,
nausea, vomiting and
headache. Later the patient
may experience a sensation
of "pins and needles" in the
legs and even paralysis. In
rare cases, the diaphragm is
paralyzed and the patient
cannot breathe unaided.
There is no drug therapy
against poliomyelitis;
however, the disease can be
prevented by immunization
with polio vaccine
.
Poliomyelitis is a communicable disease
caused by viral infection and occurs
through direct contact with infected
secretions. Polio is found worldwide, but
immunization has reduced the incidence.
Clinical polio affects the central nervous
system (brain and spinal cord). Disability is
more common than death.
Diphtheria is an infectious disease
transmitted by the diphtheria
bacterium. The signs of the
disease are: fever, reddening and
swelling of the throat and tonsils
with the formation of grayishwhite exudates which bleed when
scratched and cause a sweetish
offensive breath. The complications
of diphtheria include: inflammation
of the cardiac muscle, difficulty in
swallowing, and paralysis of the
facial muscles, extremities and
diaphragm - resulting, in severe
cases, in cessation of breathing and kidney damage. Diphtheria
antitoxin may be injected to
combat the toxin released by the
diphtheria bacterium. The disease
can be prevented by immunization
The disease may be mild and go
unrecognized, or it may become
progressive. If toxin enters the
bloodstream the patient may
develop inflammation of the heart
muscle (myocarditis) which is the
most commonly seen and most
worrisome complication. Toxic
effects on the nervous system may
cause temporary paralysis
Symptoms
•Sore throat, which may range from mild to
severe with painful swallowing, hoarseness.
Drooling suggests that airway obstruction is
about to occur.
•Fever and chills.
•Bloody, watery (serosanguineous) drainage
from nose.
•Croup-like (barking) cough.
•Stridor, difficulty breathing or rapid breathing.
Absent breathing (apnea) may occur. Bluish
coloration of the skin may be caused by lack of
oxygen.
•Skin lesions can be seen in cutaneous
diphtheria (usually seen in the tropics).
Pertussis or whooping
cough is an infectious
disease transmitted by
the bacterium Bordetella
pertussis. The signs of
the disease are:
coughing fits
accompanied by a loud
"whooping" sound as the
child inhales, and
vomiting. The
complications of
whooping cough include:
pneumonia and brain
damage caused by
oxygen deficiency. The
disease can be treated
with antibiotics or
prevented by
immunization.
Whooping cough is one of those
diseases most people think is history but the dangerous germ that can leave
sufferers gasping for air is making a
comeback.
The cough so strong it can break a rib
once hit mostly babies and toddlers, but
now it's striking more and more teenagers and young adults. Apparently the
whooping cough vaccinations
Americans get as babies eventually can
wear off.
So experts warn new parents to keep infants
away from anyone who's coughing, even as
scientists study whether millions of
Americans should start getting booster doses
of whooping cough vaccine just as many get
regular tetanus shots
Tetanus is an
infectious disease
transmitted when the
Clostridium tetani
bacillus enters open
wounds. The signs of
the disease are:
muscle spasms
throughout the entire
body, lockjaw,
paralysis of the
respiratory muscles
and even cessation of
respiration. A tetanus
antitoxin can be
injected against the
toxin produced by the
tetanus bacterium.
The disease can be
prevented by
immunization.
Symptoms
Spasms and tightening of the jaw muscle (hence
the name lockjaw)
•Stiffening of the neck & other muscles
•Spasms of the neck and other muscles
•Stiffness of the chest muscles
•Stiffness of the abdominal muscles Spasms
and stiffness of the back muscles, often
causing arching (opisthotonos)
•Tetanic seizures (painful, powerful bursts of
muscle contractions)
•Irritability
•Fever
Scarlet fever is an
infectious disease
transmitted by the
Streptococcus bacterium.
The signs of the disease
are: high fever, reddening
of the throat and tonsils,
punctuate exudate on the
tonsils, strawberry tongue
and a skin rash which
starts on the chest and
rapidly spreads to the
arms and legs. The
complications of scarlet
fever include:
inflammation of the
cardiac muscle, kidneys
and middle ear. Scarlet
fever can be treated with
antibiotics
.
Haemophilus
influenzae Type b is
a bacillus which can
cause blood
poisoning, throat
infections with
swelling of the
larynx and
meningitis in
children. The
infection caused by
this bacillus can be
treated with
antibiotics or
prevented by
immunization.
This picture shows the organism Haemophilus influenza.
Infections caused by Haemophilus influenza usually occur
in children under 6 years old and are extremely serious.
Haemophilus (type B) is responsible for meningitis,
periorbital cellulitis, buccal cellulitis and epiglottitis, septic
arthritis, osteomyelitis, pericarditis, and bacteremia. The
small organisms live within cells (intracellular) as shown in
this picture. (Courtesy of the Centers for Disease Control.)
Hepatitis A and B is an inflammation of
the liver caused by the hepatitis A and
hepatitis B viruses.
Hepatitis A can be transmitted by
infected food or water or by failure to
observe hygienic precautions. Hepatitis
B can only be transmitted directly by
the blood, urine, feces, milk or semen
of an infected individual. In both forms
of the disease, several months may
elapse between the time of infection
and the first signs of the disease. The
signs of the disease include: high fever
(for hepatitis A), nausea, vomiting,
abdominal pain, diarrhea or constipation,
and jaundice of the skin or eyes.
Hepatitis A is the milder form of the
disease and usually lasts no longer than
3-4 weeks. Hepatitis B, in contrast,
may become chronic and result in liver
damage. A complete recovery is also
possible with this form, however.
There is no direct drug therapy for
hepatitis. However, there are vaccines
against both forms of the disease.
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