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Transcript
Herpes simplex
Herpes simplex (Greek: ἕρπης - herpes, lit.
"creeping") is a viral disease caused by both Herpes
simplex virus type 1 (HSV-1) and type 2 (HSV-2).
Infection with the herpes virus is categorized into one
of several distinct disorders based on the site of
infection. Oral herpes, the visible symptoms of which
are colloquially called cold sores or fever blisters,
infects the face and mouth. Oral herpes is the most
common form of infection. Genital herpes, known
simply as herpes, is the second most common form of
herpes.
Herpes simplex
Classification
• Herpes simplex is divided into two types:
HSV type 1 and HSV type 2.[2] HSV1
primarily causes mouth, throat, face, eye,
and central nervous system infections,
while HSV2 primarily causes anogenital
infections.[2] However, each may cause
infections in all areas.[2]
Signs and symptoms
• HSV infection causes several distinct medical disorders.
Common infection of the skin or mucosa may affect the
face and mouth (orofacial herpes), genitalia (genital
herpes), or hands (herpetic whitlow). More serious
disorders occur when the virus infects and damages the
eye (herpes keratitis), or invades the central nervous
system, damaging the brain (herpes encephalitis).
Patients with immature or suppressed immune systems,
such as newborns, transplant recipients, or AIDS
patients are prone to severe complications from HSV
infections. HSV infection has also been associated with
cognitive deficits of bipolar disorder,[3] and Alzheimer's
disease,[4] although this is often dependent on the
genetics of the infected person.
Herpetic gingivostomatitis
• Herpetic gingivostomatitis is often the
initial presentation during the first herpes
infection. It is of greater severity than
herpes labialis which is often the
subsequent presentations.
Herpes labialis
• Infection occurs when the virus comes into
contact with oral mucosa or abraded skin.
Herpes genitalis
• When symptomatic, the typical
manifestation of a primary HSV-1 or HSV2 genital infection is clusters of inflamed
papules and vesicles on the outer surface
of the genitals resembling cold sores.
Herpes esophagitis
• Symptoms may include painful swallowing
(odynophagia) and difficulty swallowing
(dysphagia). It is often associated with
impaired immune function (e.g. HIV/AIDS,
immunosuppression in solid organ
transplants).
Treatment
• There are several antivirals that are
effective for treating herpes including:
aciclovir (acyclovir), valaciclovir
(valacyclovir), famciclovir, and penciclovir.
Aciclovir was the first discovered and is
now available in generic.
Prognosis
• Many HSV-infected people experience recurrence within
the first year of infection.[5] Prodrome precedes
development of lesions. Prodromal symptoms include
tingling (paresthesia), itching, and pain where
lumbosacral nerves innervate the skin. Prodrome may
occur as long as several days or as short as a few hours
before lesions develop. Beginning antiviral treatment
when prodrome is experienced can reduce the
appearance and duration of lesions in some individuals.
During recurrence, fewer lesions are likely to develop,
lesions are less painful and heal faster (within 5–10 days
without antiviral treatment) than those occurring during
the primary infection.[5] Subsequent outbreaks tend to
be periodic or episodic, occurring on average four to five
times a year when not using antiviral therapy.
Herpes zoster
• Herpes zoster (or simply zoster), commonly known as
shingles and also known as zona, is a viral disease
characterized by a painful skin rash with blisters in a
limited area on one side of the body, often in a stripe.
The initial infection with varicella zoster virus (VZV)
causes the acute (short-lived) illness chickenpox which
generally occurs in children and young people. Once an
episode of chickenpox has resolved, the virus is not
eliminated from the body but can go on to cause
shingles—an illness with very different symptoms—often
many years after the initial infection. Despite the
similarity of name, herpes zoster is not the same disease
as herpes simplex, although both the varicella zoster
virus and herpes simplex virus belong to the same viral
subfamily (Alphaherpesvirinae).
Signs and symptoms
• The earliest symptoms of herpes zoster, which include
headache, fever, and malaise, are nonspecific, and may
result in an incorrect diagnosis.[5][9] These symptoms
are commonly followed by sensations of burning pain,
itching, hyperesthesia (oversensitivity), or paresthesia
("pins and needles": tingling, pricking, or numbness).[10]
The pain may be mild to extreme in the affected
dermatome, with sensations that are often described as
stinging, tingling, aching, numbing or throbbing, and can
be interspersed with quick stabs of agonizing pain.[11]
Development of the shingles
rash
Day 1
Day 2
Pathophysiology
Progression
of herpes
zoster. A
cluster of
small bumps
(1) turns into
blisters (2).
The blisters
fill with
lymph, break
open (3),
crust over
(4), and
finally
disappear.
Postherpetic
neuralgia can
sometimes
Diagnosis
• Laboratory tests are available to diagnose
herpes zoster. The most popular test
detects VZV-specific IgM antibody in
blood; this only appears during chickenpox
or herpes zoster and not while the virus is
dormant.[23] In larger laboratories, lymph
collected from a blister is tested by
polymerase chain reaction for VZV DNA,
or examined with an electron microscope
for virus particles.[24]
Herpes zoster on the chest
Prevention
• In the United Kingdom and other parts of Europe,
population-based varicella immunization is not practised.
The rationale is that until the entire population could be
immunized, adults who have previously contracted VZV
would instead derive benefit from occasional exposure to
VZV (from children), which serves as a booster to their
immunity to the virus, and may reduce the risk of
shingles later on in life.[33] The UK Health Protection
Agency states that, while the vaccine is licensed in the
UK, there are no plans to introduce it into the routine
childhood immunization scheme, although it may be
offered to healthcare workers who have no immunity to
VZV.[34]
Treatment
• The aims of treatment are to limit the
severity and duration of pain, shorten the
duration of a shingles episode, and reduce
complications. Symptomatic treatment is
often needed for the complication of
postherpetic neuralgia.[
Analgesics
• People with mild to moderate pain can be
treated with over-the-counter analgesics. Topical
lotions containing calamine can be used on the
rash or blisters and may be soothing.
Occasionally, severe pain may require an opioid
medication, such as morphine. Once the lesions
have crusted over, capsaicin cream (Zostrix) can
be used. Topical lidocaine and nerve blocks may
also reduce pain.[38] Administering gabapentin
along with antivirals may offer relief of
postherpetic neuralgia
Antivirals
• The drugs are used both as prophylaxis (for
example in AIDS patients) and as therapy during
the acute phase. Antiviral treatment is
recommended for all immunocompetent
individuals with herpes zoster over 50 years old,
preferably given within 72 hours of the
appearance of the rash.[39] Complications in
immunocompromised individuals with herpes
zoster may be reduced with intravenous
acyclovir. In people who are at a high risk for
repeated attacks of shingles, five daily oral
doses of acyclovir are usually effective.[1]
Steroids
• Orally administered corticosteroids are
frequently used in treatment of the
infection, despite clinical trials of this
treatment being unconvincing.
Nevertheless, one trial studying
immunocompetent patients older than 50
years of age with localized herpes zoster,
suggested that administration of
prednisone with aciclovir improved healing
time and quality of life
Prognosis
• The rash and pain usually subside within three to five
weeks, but about one in five patients develops a painful
condition called postherpetic neuralgia, which is often
difficult to manage. In some patients, herpes zoster can
reactivate presenting as zoster sine herpete: pain
radiating along the path of a single spinal nerve (a
dermatomal distribution), but without an accompanying
rash. This condition may involve complications that affect
several levels of the nervous system and cause multiple
cranial neuropathies, polyneuritis, myelitis, or aseptic
meningitis. Other serious effects that may occur in some
cases include partial facial paralysis (usually temporary),
ear damage, or encephalitis.
Influenza
• Influenza, commonly referred to as the
flu, is an infectious disease caused by
RNA viruses of the family
Orthomyxoviridae (the influenza viruses),
that affects birds and mammals. The most
common symptoms of the disease are
chills, fever, sore throat, muscle pains,
severe headache, coughing,
weakness/fatigue and general discomfo
Types of virus
• In virus classification influenza viruses are
RNA viruses that make up three of the five
genera of the family Orthomyxoviridae:[18]
• Influenzavirus A
• Influenzavirus B
• Influenzavirus C
Influenzavirus A
• This genus has one species, influenza A virus.
Wild aquatic birds are the natural hosts for a
large variety of influenza A. Occasionally,
viruses are transmitted to other species and may
then cause devastating outbreaks in domestic
poultry or give rise to human influenza
pandemics.[21] The type A viruses are the most
virulent human pathogens among the three
influenza types and cause the most severe
disease
Influenzavirus B
• This genus has one species, influenza B virus.
Influenza B almost exclusively infects
humans[22] and is less common than influenza
A. The only other animals known to be
susceptible to influenza B infection are the
seal[24] and the ferret.[25] This type of influenza
mutates at a rate 2–3 times slower than type
A[26] and consequently is less genetically
diverse, with only one influenza B serotype.
Influenzavirus C
• This genus has one species, influenza C
virus, which infects humans, dogs and
pigs, sometimes causing both severe
illness and local epidemics.[29][30]
However, influenza C is less common than
the other types and usually only causes
mild disease in children.
Signs and symptoms
• Symptoms of influenza can start quite suddenly
one to two days after infection. Usually the first
symptoms are chills or a chilly sensation, but
fever is also common early in the infection, with
body temperatures ranging from 38-39 °C
(approximately 100-103 °F).[53] Many people
are so ill that they are confined to bed for several
days, with aches and pains throughout their
bodies, which are worse in their backs and legs
Symptoms of influenza may
include:
•
•
•
•
•
•
•
•
•
•
Fever and extreme coldness (chills shivering, shaking (rigor))
Cough
Nasal congestion
Body aches, especially joints and throat
Fatigue
Headache
Irritated, watering eyes
Reddened eyes, skin (especially face), mouth, throat and nose
Petechial Rash[54]
In children, gastrointestinal symptoms such as diarrhea and
abdominal pain,[55][56] (may be severe in children with influenza
B)[57]
Treatment
• People with the flu are advised to get plenty of rest, drink
plenty of liquids, avoid using alcohol and tobacco and, if
necessary, take medications such as acetaminophen
(paracetamol) to relieve the fever and muscle aches
associated with the flu.[109] Children and teenagers with
flu symptoms (particularly fever) should avoid taking
aspirin during an influenza infection (especially influenza
type B), because doing so can lead to Reye's syndrome,
a rare but potentially fatal disease of the liver.[110] Since
influenza is caused by a virus, antibiotics have no effect
on the infection; unless prescribed for secondary
infections such as bacterial pneumonia. Antiviral
medication can be effective, but some strains of
influenza can show resistance to the standard antiviral
drugs
acquired immunodeficiency
syndrome
• is a disease of the human immune system
caused by the human immunodeficiency
virus
History
• AIDS was first reported June 5, 1981, when the U.S.
Centers for Disease Control (CDC) recorded a cluster of
Pneumocystis carinii pneumonia (now still classified as
PCP but known to be caused by Pneumocystis jirovecii)
in five homosexual men in Los Angeles.[14] In the
beginning, the CDC did not have an official name for the
disease, often referring to it by way of the diseases that
were associated with it, for example, lymphadenopathy,
the disease after which the discoverers of HIV originally
named the virus.[15][16] They also used Kaposi's
Sarcoma and Opportunistic Infections, the name by
which a task force had been set up in 1981
Signs and symptoms
• The symptoms of AIDS are primarily the
result of conditions that do not normally
develop in individuals with healthy immune
systems. Most of these conditions are
infections caused by bacteria, viruses,
fungi and parasites that are normally
controlled by the elements of the immune
system that HIV damages.
Cause
• Sexual transmission
Blood products
Perinatal transmission
Pathophysiology
• The pathophysiology of AIDS is complex, as is
the case with all syndromes.[95] Ultimately, HIV
causes AIDS by depleting CD4+ T helper
lymphocytes. This weakens the immune system
and allows opportunistic infections. T
lymphocytes are essential to the immune
response and without them, the body cannot
fight infections or kill cancerous cells. The
mechanism of CD4+ T cell depletion differs in
the acute and chronic phases
Cells affected
• The virus, entering through which ever route, acts
primarily on the following cells:[101]
• Lymphoreticular system:
–
–
–
–
CD4+ T-Helper cells
Macrophages
Monocytes
B-lymphocytes
• Certain endothelial cells
• Central nervous system:
–
–
–
–
Microglia of the nervous system
Astrocytes
Oligodendrocytes
Neurones – indirectly by the action of cytokines and the gp-120
disease staging system
• Stage I: HIV infection is asymptomatic and not
categorized as AIDS
• Stage II: includes minor mucocutaneous
manifestations and recurrent upper respiratory
tract infections
• Stage III: includes unexplained chronic diarrhea
for longer than a month, severe bacterial
infections and pulmonary tuberculosis
• Stage IV: includes toxoplasmosis of the brain,
candidiasis of the esophagus, trachea, bronchi
or lungs and Kaposi's sarcoma; these diseases
are indicators of AIDS.
Prevention
• The three main transmission routes of HIV are
sexual contact, exposure to infected body fluids
or tissues, and from mother to fetus or child
during perinatal period. It is possible to find HIV
in the saliva, tears, and urine of infected
individuals, but there are no recorded cases of
infection by these secretions, and the risk of
infection is negligible.[115] Anti-retroviral
treatment of infected patients also significantly
reduces their ability to transmit HIV to others, by
reducing the amount of virus in their bodily fluids
to undetectable levels.
Body fluid exposure
• Health care workers can reduce exposure to HIV
by employing precautions to reduce the risk of
exposure to contaminated blood. These
precautions include barriers such as gloves,
masks, protective eyeware or shields, and
gowns or aprons which prevent exposure of the
skin or mucous membranes to blood borne
pathogens. Frequent and thorough washing of
the skin immediately after being contaminated
with blood or other bodily fluids can reduce the
chance of infection
Mother-to-child
• Current recommendations state that when
replacement feeding is acceptable, feasible,
affordable, sustainable and safe, HIV-infected
mothers should avoid breast-feeding their infant.
However, if this is not the case, exclusive breastfeeding is recommended during the first months
of life and discontinued as soon as
possible.[134] It should be noted that women
can breastfeed children who are not their own;
see wet nurse.
Antiviral therapy
• Current treatment for HIV infection consists of
highly active antiretroviral therapy, or
HAART.[139] This has been highly beneficial to
many HIV-infected individuals since its
introduction in 1996 when the protease inhibitorbased HAART initially became available.[13]
Current optimal HAART options consist of
combinations (or "cocktails") consisting of at
least three drugs belonging to at least two types,
or "classes," of antiretroviral agents.
Abacavir – a nucleoside analog
reverse transcriptase inhibitor
Prognosis
• Without treatment, the net median survival time after
infection with HIV is estimated to be 9 to 11 years,
depending on the HIV subtype,[8] and the median
survival rate after diagnosis of AIDS in resource-limited
settings where treatment is not available ranges between
6 and 19 months, depending on the study.[164] In areas
where it is widely available, the development of HAART
as effective therapy for HIV infection and AIDS reduced
the death rate from this disease by 80%, and raised the
life expectancy for a newly diagnosed HIV-infected
person to about 20 years
Recurrent aphthous stomatitis
• An aphthous ulcer (pronounced /ˈæfθəs/
af-thəs), also known as a canker sore, is
a type of mouth ulcer which presents as a
painful open sore inside the mouth[1] or
upper throat characterized by a break in
the mucous membrane. Its cause is
unknown, but they are not contagious.
Aphthous ulcer
Classification
• Aphthous ulcers are classified according
to the diameter of the lesion.
Minor ulceration
• Minor aphthous ulcers indicate that the
lesion size is between 3–10 mm (0.1–0.4
in). The appearance of the lesion is that of
an erythematous halo with yellowish or
grayish color. Pain that affects quality of
life is the obvious characteristic of the
lesion. When the ulcer is white or grayish,
the ulcer will be extremely painful and the
affected lip may swell. They may last
about 2 weeks.
Major ulcerations
• Major aphthous ulcers have the same
appearance as minor ulcerations, but are
greater than 10 mm in diameter and are
extremely painful. They usually take more
than a month to heal, and frequently leave
a scar. These typically develop after
puberty with frequent recurrences. They
occur on movable non-keratinizing oral
surfaces, but the ulcer borders may extend
onto keratinized surfaces.
Herpetiform ulcerations
• This is the most severe form. It occurs
more frequently in females, and onset is
often in adulthood. It is characterized by
small, numerous, 1–3 mm lesions that
form clusters. They typically heal in less
than a month without scarring. Supportive
treatment is almost always necessary
Signs and symptoms
• Aphthous ulcers usually begin with a
tingling or burning sensation at the site of
the future aphthous ulcer. In a few days,
they often progress to form a red spot or
bump, followed by an open ulcer.
Large aphthous ulcer on the lower
lip
Causes
• The exact cause of many aphthous ulcers
is unknown but citrus fruits (e.g., oranges
and lemons), physical trauma, stress, lack
of sleep, sudden weight loss, food
allergies, immune system reactions,[5] and
deficiencies in vitamin B12, iron, and folic
acid[6] may contribute to their
development.
Prevention
• Oral measures
• Regular use of non-alcoholic mouthwash may help prevent or
reduce the frequency of sores. Informal studies suggest that
mouthwash may help to temporarily relieve pain.[24]
• In some cases, switching toothpastes can prevent aphthous ulcers
from occurring, with research looking at the role of sodium dodecyl
sulfate (sometimes called sodium lauryl sulfate, or with the
acronymes SDS or SLS), a detergent found in most toothpastes.
Using toothpaste free of this compound has been found in several
studies to help reduce the amount, size, and recurrence of
ulcers.[25][26][27]
• Dental braces are a common physical trauma that can lead to
aphthous ulcers and the dental bracket can be covered with wax to
reduce abrasion of the mucosa. Avoidance of other types of physical
and chemical trauma will prevent some ulcers, but, since such
trauma is usually accidental, this type of prevention is not usually
practical.
Nutrition
• Zinc deficiency has been reported in
people with recurrent aphthous ulcers.[28]
The few small studies looking into the role
of zinc supplementation have mostly
reported positive results particularly for
those people with deficiency,[29] although
some research has found no therapeutic
effect
Treatment
• A number of different treatments exist for apthous ulcers
including: analgesics, anesthetics agents, antiseptics,
anti-inflammatory agents, steroids, sucralfate,
tetracycline suspension, and silver nitrate.[31]
Amlexanox paste has been found to speed healing and
alleviate pain.[32]
• Suggestions to reduce the pain caused by an ulcer
include: avoiding spicy food, rinsing with salt water or
over-the-counter mouthwashes, proper oral hygiene and
non-prescription local anesthetics.[33] Active ingredients
in the latter generally include benzocaine,[34]
benzydamine or choline salicylate,[35] and phenol
Foot-and-mouth disease
• Foot-and-mouth disease or hoof-andmouth disease (Aphtae epizooticae) is
an infectious and sometimes fatal viral
disease that affects cloven-hoofed
animals, including domestic and wild
bovids. The virus causes a high fever for
two or three days, followed by blisters
inside the mouth and on the feet that may
rupture and cause lameness.
Ruptured oral blister in diseased
cow.
• Foot-and-mouth disease is a severe plague for
animal farming, since it is highly infectious and
can be spread by infected animals through
aerosols, through contact with contaminated
farming equipment, vehicles, clothing or feed,
and by domestic and wild predators.[1] Its
containment demands considerable efforts in
vaccination, strict monitoring, trade restrictions
and quarantines, and occasionally the
elimination of millions of animals.
• Susceptible animals include cattle, water buffalo,
sheep, goats, pigs, antelope, deer, and bison. It
has also been known to infect hedgehogs,
elephants,[1][2] llama, and alpaca may develop
mild symptoms, but are resistant to the disease
and do not pass it on to others of the same
species.[1] In laboratory experiments, mice and
rats and chickens have been successfully
infected by artificial means, but it is not believed
that they would contract the disease under
natural conditions.[1] Humans are very rarely
affected.
• The virus responsible for the disease is a
picornavirus, the prototypic member of the
genus Aphthovirus. Infection occurs when
the virus particle is taken into a cell of the
host. The cell is then forced to
manufacture thousands of copies of the
virus, and eventually bursts, releasing the
new particles in the blood. The virus is
highly variable,[3] which limits the
effectiveness of vaccination.
Clinical signs
• The incubation period for foot-and-mouth disease virus
has a range between 2 and 12 days.[6] The disease is
characterized by high fever that declines rapidly after two
or three days; blisters inside the mouth that lead to
excessive secretion of stringy or foamy saliva and to
drooling; and blisters on the feet that may rupture and
cause lameness. Adult animals may suffer weight loss
from which they do not recover for several months as
well as swelling in the testicles of mature males, and in
cows, milk production can decline significantly. Though
most animals eventually recover from FMD, the disease
can lead to myocarditis (inflammation of the heart
muscle) and death, especially in newborn animals. Some
infected animals remain asymptomatic, but they
nonetheless carry FMD and can transmit it to others.
Ruptured blisters on the feet of a
pig
Foot-and-mouth disease
• Humans can be infected with foot-and-mouth disease
through contact with infected animals, but this is
extremely rare. Some cases were caused by laboratory
accidents. Because the virus that causes FMD is
sensitive to stomach acid, it cannot spread to humans
via consumption of infected meat, except in the mouth
before the meat is swallowed. In the UK, the last
confirmed human case occurred in 1966,[10][11] and
only a few other cases have been recorded in countries
of continental Europe, Africa, and South America.
Symptoms of FMD in humans include malaise, fever,
vomiting, red ulcerative lesions (surface-eroding
damaged spots) of the oral tissues, and sometimes
vesicular lesions (small blisters) of the skin.
Economic and ethical issues
• Epidemics of FMD have resulted in the
slaughter of millions of animals, despite
this being a frequently nonfatal disease for
adult animals (2-5% mortality), though
young animals can have a high mortality
Treatment
• In severe foot and mouth disease in debilitated
children with concomitant diseases of patients
hospitalized in other cases are isolated at home
in the disappearance of clinical symptoms.
Aphthae in the mouth obroblyuyut a cotton swab
soaked 4% solution of silver nitrate (silver
nitrate) or 3% solution of hydrogen peroxide
required frequent mouthwashes 0.1% solution of
potassium permanganate, 0.25% solution of
novocaine. Any damage to the eyes appoint
sulfatsil-sodium (albutsyd). Apply vitamins,
antihistamines. When complications - antibiotics.
Treatment
• Patients with foot and mouth disease be
hospitalized for at least 14 days.
Appointed by the diet, in the mechanical
and chemical terms possible sparing
mucous (semi digestible food 5-6 times a
day in small portions, before taking a
patient give 0.1 g anestezina), drink plenty
of liquids. Sometimes resorted to feeding
through a tube. Of paramount importance
is the oral health care.
Thank you for attention