Download risk of infection east and southwest asia

16 may 2012
RISK OF INFECTION EAST AND SOUTHWEST ASIA
RECENT OUTBREAKS OF INFECTIOUS DISEASES
Country
China
Japan
Korea
Mongolia
Brunei
Burma
Disease
Date of Outbreak
Avian influenza
Polio
Hand, Foot and Mouth disease
Streptococcus suis
SARS
SARS
Staphylococcal food intoxication
SARS
Measles
SARS
no data available
no data available
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2012, 2011,2010,
2009,2008
2012, 2000
2008
2005
2003
2000
2004
2001
2004, 2003
Cambodia
East Timor
Indonesia
Laos
Malaysia
Philippines
Singapore
Thailand
Viet Nam
Avian influenza
no data available
no data available
Avian influenza
SARS
Ebola Reston
Meningococcal disease
SARS
SARS
Meningococcal disease
Avian influenza
SARS
Streptococcus suis
Avian influenza
SARS
Cholera
Streptococcus suis
2012, 2011,2010,
2009,2008
2007
2003
2009
2005
2003
2003
2001, 2000
2006, 2005, 2004
2003
2005
2012, 2010, 2009,
2008, 2007
2008
2003
2005
MODE OF TRANSMISSION, SIGNS AND SYMPTOMS OF SELECTED
DISEASES
AVIAN INFLUENZA
Transmission and etiology
Avian influenza is flu infection in birds. The virus that causes the bird infection can change (mutate) to
infect humans. Such mutation could start a deadly worldwide epidemic. Human cases of avian influenza
A (H5N1) have been reported in Asia, Africa, Europe, Indonesia, Vietnam, the Pacific, and the near East.
Hundreds of people have become sick with this virus. Slightly more than 60% of those who became ill
have died.
Clinical signs and symptoms
Symptoms of avian flu infection in humans depend on the strain of virus. Infection with the H5N1 virus
in humans causes typical flu-like symptoms, which might include: cough (dry or productive, diarrhea,
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difficulty breathing, fever greater than 100.4°F (38°C), headache, malaise, muscle aches, runny
nose and sore throat.
Prevention
The Food and Drug Administration has approved one vaccine to prevent infection with one strain of
H5N1 bird flu virus. This vaccine isn't available to the public, but the U.S. government is
stockpiling it and will distribute it in the event of an outbreak. It's intended to help protect adults
ages 18 to 64 and could be used early in such an outbreak to provide limited protection until another
vaccine, designed to protect against the specific form of the virus causing the outbreak, is developed
and produced.
Recommendations for travelers
If you're traveling to Southeast Asia or to any region with bird flu outbreaks, consider these public
health recommendations:
Avoid domesticated birds. If possible, avoid rural areas, small farms and open-air markets.
Wash your hands. This is one of the simplest and best ways to prevent infections of all kinds. Use
an alcohol-based hand sanitizer containing at least 60 percent alcohol when you travel.
Ask about a flu shot. Before traveling, ask your doctor about a flu shot. It won't protect you
specifically from bird flu, but it may help reduce the risk of simultaneous infection with bird and
human flu viruses. Avoid cross-contamination.
Use hot, soapy water to wash cutting boards, utensils and all surfaces that have come into contact
with raw poultry.
Cook thoroughly. Cook chicken until the juices run clear, and it reaches a minimum internal
temperature of 165 F (74 C).
Steer clear of raw eggs. Because eggshells are often contaminated with bird droppings, avoid foods
containing raw or undercooked eggs.
CHOLERA
Transmission and etiology
Cholera is an infection in the small intestine caused by the bacterium Vibrio cholerae. Cholera is typically
transmitted by either contaminated food or water. In the developed world, seafood is the usual cause,
while in the developing world it is more often water. Cholera has been found in only two other animal
populations: shellfish and plankton. People infected with cholera often have diarrhea, and if this highly
liquid stool, colloquially referred to as "rice-water" or "faucet butt", contaminates water used by others,
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disease transmission may occur. The source of the contamination is typically other cholera sufferers when
their untreated diarrheal discharge is allowed to get into waterways, groundwater or drinking water
supplies. Drinking any infected water and eating any foods washed in the water, as well as shellfish living
in the affected waterway, can cause a person to contract an infection. Cholera is rarely spread directly
from person to person. Both toxic and nontoxic strains exist. Nontoxic strains can acquire toxicity through
a temperate bacteriophage.
Coastal cholera outbreaks typically follow zooplankton blooms, thus making cholera a zoonotic disease.
Clinical signs and symptoms
For every symptomatic person, 3 to 100 people get the infection but remain asymptomatic. The primary
symptoms of cholera are profuse, painless diarrhea and vomiting of clear fluid. These symptoms
usually start suddenly, one to five days after ingestion of the bacteria. The diarrhea is frequently described
as "rice water" may have a fishy odor. An untreated person with cholera may produce 10–20 liters of
diarrhea a day with fatal results. Cholera has been nicknamed the "blue death" due to a patient's skin
turning a bluish-gray hue from extreme loss of fluids If the severe diarrhea is not treated with
intravenous rehydration, it can result in life-threatening dehydration and electrolyte imbalances. The
typical symptoms of dehydration include low blood pressure, poor skin turgor (wrinkled hands), sunken
eyes, and a rapid pulse.
Prevention
Although cholera may be life-threatening, prevention of the disease is normally straightforward if proper
sanitation practices are followed.
EBOLA RESTON (REBOV)
Transmission and etiology
The Ebola virus belongs to the Filoviridae family (filovirus) and is comprised of five distinct species:
Zaïre, Sudan, Côte d’Ivoire, Bundibugyo and Reston. Zaïre, Sudan and Bundibugyo species have been
associated with large Ebola hemorrhagic fever (EHF) outbreaks in Africa with high case fatality ratio
(25–90%). The Côte d’Ivoire and Reston have not associated with high fatality. Reston virus can infect
humans but no serious illness or deaths in humans have been reported to date.
Clinical signs and symptoms
Human infection with the Ebola Reston subtype, found in the Western Pacific, has only caused
asymptomatic illness, meaning that those who contract the disease do not experience clinical illness. The
transmissions of the Ebola Reston strain through the handling of pigs or cynomolgus monkeys have been
reported. The infected pigs may be asymptomatic increasing the risk of human infection. The Ebola
Reston virus is endemic in the Philippines.
Prevention
The use of protective gloves when processing raw pork is recommended.
HAND, FOOT AND MOUTH DISEASE (HFMD)
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Transmission and etiology
Hand, foot, and mouth disease is caused by viruses that belong to the Enterovirus genus (group). The
Coxsackievirus A16 is the most common cause of hand, foot, and mouth disease in the United States, but
other coxsackieviruses have been associated with the illness. Enterovirus 71 has also been associated with
hand, foot, and mouth disease and outbreaks of this disease.
The 20 deaths of hand, foot and mouth disease (HFMD) due to enterovirus (EV-71) have been reported in
China. All fatal cases died of serious complications such as neurogenic pulmonary edema due to
infection. The overall case fatality rate has decreased from 11% during March 10-31 to 0.2% during April
17-29. Hand, foot, and mouth disease is a common viral illness that usually affects infants and children
younger than 5 years old. However, it can sometimes occur in adults. Hand, foot, and mouth disease is
spread from person to person by direct contact with the infectious viruses that cause this disease. These
viruses are found in the nose and throat secretions (such as saliva, sputum, or nasal mucus), fluid in
blisters, and stool of infected persons. The viruses may be spread when infected persons touch objects and
surfaces that are then touched by others. Infected persons are most contagious during the first week of the
illness. The viruses that cause hand, foot, and mouth disease can remain in the body for weeks after a
person’s symptoms have gone away. This means that infected people can still pass the infection to others
even though they may appear well. Also, some people who are infected and shedding the virus, including
most adults, may have no symptoms. Hand, foot, and mouth disease is not transmitted to or from pets or
other animals.
Clinical signs and symptoms
Symptoms of hand, foot, and mouth disease include fever, blister-like sores in the mouth (herpangina),
and a skin rash. Hand, foot, and mouth disease usually starts with a fever, poor appetite, a vague feeling
of being unwell (malaise), and sore throat. One or 2 days after fever starts, painful sores usually
develop in the mouth (herpangina). They begin as small red spots that blister and that often become
ulcers. The sores are often in the back of the mouth. A skin rash develops over 1 to 2 days. The rash has
flat or raised red spots, sometimes with blisters. The rash is usually on the palms of the hands and soles of
the feet; it may also appear on the knees, elbows, buttocks or genital area. Some people, especially young
children, may get dehydrated if they are not able to swallow enough liquids because of painful mouth
sores. Persons infected with the viruses that cause hand, foot, and mouth disease may not get all the
symptoms of the disease. They may only get the mouth sore or skin rash. Complications of HFMD are
uncommon and may include: viral or "aseptic" meningitis (rare), inflammation of the brain
(encephalitis), rarer. The fingernail and toe nail loss were reported. The symptoms of meningitis are:
fever, headache, stiff neck, or back pain. Hand, foot, and mouth disease is often confused with foot-andmouth disease (also called hoof-and-mouth disease), a disease of cattle, sheep, and swine. However, the
two diseases are caused by different viruses and are not related.
Prevention
There is no vaccine to protect against the viruses that cause hand, foot, and mouth disease. A person can
lower their risk of being infected by: washing hands, disinfecting object and surface, avoiding close
contact with peoples infected.
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MEASLES
Transmission and etiology
A total of 39 537 cases including six deaths has been reported nationwide from March 2000 through
January 2001 in Korea. The outbreak originally started in the eastern part of the country with steady
acceleration in the number of cases since October 2000, 7449 cases have been reported in January 2001.
Measles, also known as morbilli, is an infection of the respiratory system caused by a virus, specifically a
paramyxovirus of the genus Morbillivirus. Measles (also sometimes known as English Measles) is spread
through respiration (contact with fluids from an infected person's nose and mouth, either directly or
through aerosol transmission), and is highly contagious, 90% of people without immunity sharing living
space with an infected person will catch it. In underdeveloped nations with high rates of malnutrition and
poor healthcare, fatality rates have been as high as 28%. In immunocompromised patients (e.g. people
with AIDS) the fatality rate is approximately 30%.
An alternative name for measles in English-speaking countries is rubeola (because of rubeola means
rubella in Latin terminology used in many countries as a medical language), which is sometimes confused
with rubella (German measles); the diseases are unrelated.
Clinical signs and symptoms
Symptoms include fever, cough, runny nose, red eyes and a generalized, maculopapular,
erythematous rash. An asymptomatic incubation period occurs nine to twelve days from initial exposure
and infectivity lasts from two to four days
The classical symptoms of measles include four-day fevers and the three Cs—cough, coryza (head cold)
and conjunctivitis (red eyes). The fever may reach up to 40 °C (104 °F). Koplik's spots seen inside the
mouth are pathognomonic (diagnostic) for measles, but are not often seen, even in real cases of measles,
because they are transient and may disappear within a day of arising. The characteristic measles rash is
classically described as a generalized, maculopapular, erythematous rash that begins several days after the
fever starts. It starts on the head before spreading to cover most of the body, often causing itching. The
rash is said to "stain", changing color from red to dark brown, before disappearing. The measles rash
appears two to four days after initial symptoms, and lasts for up to eight days. Complications with
measles are relatively common, ranging from relatively mild and less serious diarrhea, to pneumonia,
Otitis media and acute encephalitis (and rarely subacute sclerosing panencephalitis); corneal ulceration
leading to corneal scarring. Complications are usually more severe in adults who catch the virus
Prevention
In developed countries, most children are immunized against measles by the age of 18 months, generally
as part of a three-part MMR vaccine (measles, mumps, and rubella). The vaccination is generally not
given earlier than this because children younger than 18 months usually retain antimeasles
immunoglobulins (antibodies) transmitted from the mother during pregnancy. A second dose is usually
given to children between the ages of four and five, to increase rates of immunity. Vaccination rates have
been high enough to make measles relatively uncommon. Even a single case in a college dormitory or
similar setting is often met with a local vaccination program, in case any of the people exposed are not
already immune.
MENINGOCOCCAL DISEASE
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Transmission and etiology
Meningococcal disease is potentially fatal and should always be viewed as a medical emergency.
Meningococcal meningitis is a bacterial form of meningitis, a serious infection of the thin lining that
surrounds the brain and spinal cord. The bacteria are transmitted from person-to-person through droplets
of respiratory or throat secretions from carriers. Close and prolonged contact, such as kissing, sneezing or
coughing on someone, or living in close quarters (such as a dormitory), sharing eating or drinking utensils
with an infected person (a carrier), facilitates the spread of the disease.
Clinical signs and symptoms
The most common symptoms are a stiff neck, high fever, sensitivity to light, confusion, headaches and
vomiting. Even when the disease is diagnosed early and adequate treatment is started, 5% to 10% of
patients die, typically within 24 to 48 hours after the onset of symptoms. Bacterial meningitis may result
in brain damage, hearing loss or a learning disability in 10% to 20% of survivors. A less common but
even more severe (often fatal) form of meningococcal disease is meningococcal septicemia, which is
characterized by a hemorrhagic rash and rapid circulatory collapse.
Prevention
Vaccination
There is a vaccine for the bacteria that causes meningococcal disease. However, available vaccines do not
cover all serogroups (“strains”) of Neisseria meningitidis bacteria. Like with any vaccine, meningococcal
vaccines are not 100% effective. This means that even if you have been vaccinated, there is still a chance
you can develop a meningococcal infection. People should know the symptoms of meningococcal
meningitis and meningococcal septicemia since early recognition and quick medical attention are
extremely important.
Antibiotics
Sometimes Neisseria meningitidis bacteria spread to other people who have had close or lengthy contact
with a patient with meningococcal disease. People in the same household, roommates, or anyone with
direct contact with a patient's oral secretions (saliva) (such as a boyfriend or girlfriend) would be
considered at increased risk of getting the infection. People who qualify as close contacts of a person with
meningococcal disease should receive antibiotics to prevent them from getting the disease. This is known
as prophylaxis.
Previous infection
Protection from previous infection does not last a lifetime and is not perfect. Therefore, routine
meningococcal vaccines are still recommended. If you get meningococcal disease twice, it is highly
possible that you have an underlying immune deficiency, which your doctor should evaluate.
POLIOMYELITIS (POLIO)
Transmission and etiology
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Poliomyelitis often called polio or infantile paralysis is an acute, viral, infectious disease spread from
person to person, primarily via the fecal-oral route. Although approximately 90% of polio infections
cause no symptoms at all, affected individuals can exhibit a range of symptoms if the virus enters the
blood stream. In about 1% of cases, the virus enters the central nervous system, preferentially infecting
and destroying motor neurons, leading to muscle weakness and acute flaccid paralysis. Different types of
paralysis may occur, depending on the nerves involved. Spinal polio is the most common form,
characterized by asymmetric paralysis that most often involves the legs. Bulbar polio leads to weakness of
muscles innervated by cranial nerves. Bulbospinal polio is a combination of bulbar and spinal paralysis.
Two basic patterns of polio infection are described: a minor illness which does not involve the central
nervous system (CNS), sometimes called abortive poliomyelitis, and a major illness involving the CNS,
which may be paralytic or nonparalytic. In most people with a normal immune system, a poliovirus
infection is asymptomatic. Rarely, the infection produces minor symptoms; these may include upper
respiratory tract infection (sore throat and fever), gastrointestinal disturbances (nausea, vomiting,
abdominal pain, constipation or, rarely, diarrhea), and influenza-like illness. The virus enters the central
nervous system in about 3% of infections. Most patients with CNS involvement develop nonparalytic
aseptic meningitis, with symptoms of headache, neck, back, abdominal and extremity pain, fever,
vomiting, lethargy and irritability. About one to five in 1000 cases progress to paralytic disease, in which
the muscles become weak, floppy and poorly controlled, and finally completely paralyzed; this condition
is known as acute flaccid paralysis. Depending on the site of paralysis, paralytic poliomyelitis is classified
as spinal, bulbar, or bulbospinal. Encephalitis, an infection of the brain tissue itself, can occur in rare
cases, and is usually restricted to infants. It is characterized by confusion, changes in mental status,
headaches, fever, and less commonly, seizures and spastic paralysis.
Because Poliomyelitis is highly contagious via the oral-oral (oropharyngeal source) and fecal-oral
(intestinal source) routes, in endemic areas, wild polioviruses can infect virtually the entire human
population. Poliomyelitis is seasonal in temperate climates, with peak transmission occurring in summer
and autumn. These seasonal differences are far less pronounced in tropical areas.
The time between first exposure and first symptoms, known as the incubation period, is usually six to 20
days, with a maximum range of three to 35 days. Virus particles are excreted in the feces for several
weeks following initial infection. Factors that increase the risk of polio infection or affect the severity of
the disease include immune deficiency, malnutrition, tonsillectomy, physical activity immediately
following the onset of paralysis, skeletal muscle injury due to injection of vaccines or therapeutic agents,
and pregnancy. Although the virus can cross the placenta during pregnancy, the fetus does not appear to
be affected by either maternal infection or polio vaccination Maternal antibodies also cross the placenta,
providing passive immunity that protects the infant from polio infection during the first few months of
life. As a precaution against infection, public swimming pools were often closed in affected areas during
poliomyelitis epidemics.
Clinical signs and symptoms
Early symptoms of paralytic polio include high fever, headache, stiffness in the back and neck,
asymmetrical weakness of various muscles, sensitivity to touch, difficulty swallowing, muscle pain,
loss of superficial and deep reflexes, paresthesia (pins and needles), irritability, constipation, or
difficulty urinating. Paralysis generally develops one to ten days after early symptoms begin, progresses
for two to three days, and is usually complete by the time the fever breaks. The likelihood of developing
paralytic polio increases with age, as does the extent of paralysis. In children, nonparalytic meningitis is
the most likely consequence of CNS involvement, and paralysis occurs in only one in 1000 cases. In
adults, paralysis occurs in one in 75 cases. In children under five years of age, paralysis of one leg is most
common; in adults, extensive paralysis of the chest and abdomen also affecting all four limbs
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(quadriplegia) is more likely. Paralysis rates also vary depending on the serotype of the infecting
poliovirus; the highest rates of paralysis (one in 200) are associated with poliovirus type 1, the lowest
rates (one in 2),
Spinal polio, the most common form of paralytic poliomyelitis, results from viral invasion of the motor
neurons of the anterior horn cells, or the ventral (front) gray matter section in the spinal column, which
are responsible for movement of the muscles, including those of the trunk, limbs and the intercostal
muscles. Virus invasion causes inflammation of the nerve cells, leading to damage or destruction of motor
neuron ganglia. When spinal neurons die, Wallerian degeneration takes place, leading to weakness of
those muscles formerly innervated by the now-dead neurons. With the destruction of nerve cells, the
muscles no longer receive signals from the brain or spinal cord; without nerve stimulation, the muscles
atrophy, becoming weak, floppy and poorly controlled, and finally completely paralyzed. Progression to
maximum paralysis is rapid (two to four days), and is usually associated with fever and muscle pain.
Deep tendon reflexes are also affected, and are usually absent or diminished; sensation (the ability to feel)
in the paralyzed limbs, however, is not affected.
The extent of spinal paralysis depends on the region of the cord affected, which may be cervical, thoracic,
or lumbar. The virus may affect muscles on both sides of the body, but more often the paralysis is
asymmetrical. Any limb or combination of limbs may be affected—one leg, one arm, or both legs and
both arms. Paralysis is often more severe proximally (where the limb joins the body) than distally (the
fingertips and toes).
Making up about 2% of cases of paralytic polio, bulbar polio occurs when poliovirus invades and
destroys nerves within the bulbar region of the brain stem. The destruction of these nerves weakens the
muscles supplied by the cranial nerves, producing symptoms of encephalitis, and causes difficulty
breathing, speaking and swallowing. Critical nerves affected are the glossopharyngeal nerve, which
partially controls swallowing and functions in the throat, tongue movement and taste; the vagus nerve,
which sends signals to the heart, intestines, and lungs; and the accessory nerve, which controls upper neck
movement. Due to the effect on swallowing, secretions of mucus may build up in the airway, causing
suffocation. Other signs and symptoms include facial weakness, caused by destruction of the trigeminal
nerve and facial nerve, which innervate the cheeks, tear ducts, gums, and muscles of the face, among
other structures; double vision; difficulty in chewing; and abnormal respiratory rate, depth, and
rhythm, which may lead to respiratory arrest. Pulmonary edema and shock are also possible, and
may be fatal.
Approximately 19% of all paralytic polio cases have both bulbar and spinal symptoms; this subtype is
called respiratory or bulbospinal polio. Here, the virus affects the upper part of the cervical spinal cord
(cervical vertebrae C3 through C5), and paralysis of the diaphragm occurs. The critical nerves affected
are the phrenic nerve, which drives the diaphragm to inflate the lungs, and those that drive the muscles
needed for swallowing. By destroying these nerves, this form of polio affects breathing, making it
difficult or impossible for the patient to breathe without the support of a ventilator. It can lead to paralysis
of the arms and legs and may also affect swallowing and heart functions.
Prevention
The, live, oral polio vaccine (OPV) and inactivated poliovirus vaccine (IPV) are available. Because OPV
is inexpensive, easy to administer, and produces excellent immunity in the intestine (which helps prevent
infection with wild virus in areas where it is endemic), it has been the vaccine of choice for controlling
poliomyelitis in many countries. On very rare occasions (about one case per 750,000 vaccine recipients),
the attenuated virus in OPV reverts into a form that can paralyze. Most industrialized countries have
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switched to IPV, which cannot revert, either as the sole vaccine against poliomyelitis or in combination
with oral polio vaccine. Salk vaccine, or inactivated poliovirus vaccine (IPV), is based on poliovirus
grown in a type of monkey kidney tissue culture (vero cell line), which is chemically inactivated with
formalin. After two doses of IPV (given by injection), 90% or more of individuals develop protective
antibody to all three serotypes of poliovirus, and at least 99% are immune to poliovirus following three
doses.
SEVERE ACUTE RESPIRATORY SYNDROME
Transmission and etiology
Though epidemiologists are still in the process of trying to understand exactly how SARS is transmitted
between humans, it is generally believed that the most common mode of transmission is through water
droplets generated when an infected person coughs or sneezes. This means that transmission is most
likely to occur in close proximity to someone who is infected or by touching a surface where these water
droplets have fallen, like a countertop. Current research indicates that SARS is not transmitted through
the air except in very close proximity; the water droplets will quickly fall to the floor or other surfaces
when they are sneezed or coughed up and do not remain suspended.
The SARS coronavirus, sometimes shortened to SARS-CoV, is the virus that causes severe acute
respiratory syndrome (SARS). On April 16, 2003, following the outbreak of SARS in Asia and secondary
cases elsewhere in the world, the World Health Organization (WHO) issued a press release stating that
the coronavirus identified by a number of laboratories was the official cause of SARS.
Clinical signs and symptoms
Once a person has contracted SARS, the first symptom that they present with is a fever of at least 38°C
(100.4°F) or higher. The early symptoms last about 2–7 days and include non-specific flu-like symptoms,
including chills, rigor, muscle aches, and an upper respiratory tract infection. In severe cases, it develops
into respiratory failure and acute headaches, diarrhea, sore throat, runny nose, malaise, and myalgia
(muscle pain). Next they develop a dry cough, shortness of breath, respiratory distress syndrome
(ARDS), and in 70-90% of the cases, they develop lymphopenia (low count of white blood cells). The
incubation period for SARS-CoV is from 2–10 days, sometimes lasting up to 13 days, with the mean
being 5 days. This means that it can take between 2–10 days for the disease to manifest itself, once you
have been exposed to the Coronavirus. The incubation period is between 2–10 days. Next, the IgM
antibody titrates to the SARS-CoV virus concentration , then peaks during the acute or early convalescent
phase (week 3) and declines by week 12.
Prevention
During the SARS outbreak, several preventative measures were taken. Travel advisories were put in place
for certain regions (including Beijing and Toronto). Quarantines were instated for people who were
infected or believed to have been in contact with people who were infected. Screening measures were set
up for travelers coming from infected areas. To limit transmission in hospitals, Standard Precautions
should be taken. Airtight isolation is not believed to be necessary as the disease is not thought to be
airborne. People coming in close contact with infected individuals should use a mask and eyewear to
cover their nose, eyes, and mouth to prevent transmission from sneezing or coughing. A significant
percent of those infected during the 2003 outbreak were health care workers, and with these simple
precautions
STAPHYLOCOCCAL FOOD INTOXICATION
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Transmission and etiology
The source of the outbreak was found to be 3 different kinds of milk which had been contaminated by
Staphylococcus aureus in a production-line valve, at a major dairy-products processing plant in Osaka.
Those affected suffered diarrhoea and vomiting due to Staphylococcus aureus enterotoxin after drinking
low-fat milk.
Staphylococcus aureus food poisoning is often caused when a food handler contaminates food products
that are served or stored at room- or refrigerator temperature. The bacteria produce a toxin in the food,
which causes most of the symptoms. The disease is also common in the U.S.
Symptoms
Symptoms usually appear within 1 - 6 hours after eating contaminated food. Usually, symptoms last only
2 days or less. They may include: nausea, vomiting for up to 24 hours, diarrhea, severe abdominal
cramps, abdominal distention and mild fever. Recovery usually occurs in 24 to 48 hours.
Prevention
It is important to prevent the contamination of food with Staphylococcus before the toxin can be
produced.
•Wash hands and under fingernails vigorously with soap and water before handling and preparing food.
•Do not prepare food if you have a nose or eye infection.
•Do not prepare or serve food for others if you have wounds or skin infections on your hands or wrists.
•Keep kitchens and food-serving areas clean and sanitized.
•If food is to be stored longer than two hours, keep hot foods hot (over 140°F) and cold foods cold (40°F
or under).
•Store cooked food in a wide, shallow container and refrigerate as soon as possible.
STREPTOCOCCUS SUIS INFECTION
Transmission and etiology
In July 2005, an outbreak of the disease in humans was reported in Sichuan, China, with higher than usual
human morbidity and mortality; over 100 cases and more than 20 deaths were initially reported. Prior to
this outbreak, less than 200 total human cases had been reported, and mortality was assumed to be less
than 10%. Details of this outbreak and a similar earlier outbreak, also in Sichuan province, were
published in 2006. A smaller outbreak occurred at the same time in Hong Kong, affecting 11 people.
The human outbreak coincided with one in the local pig populations. There was no evidence of human-tohuman transmission; all of the patients had been in direct contact with pigs. It has been suggested that the
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routes of entry of the organism in humans might be a small cut in the skin (although in some cases no
wound was detected), the nasopharynx (with positive isolation from tonsils of abattoir workers), or the
gastrointestinal tract (diarrhea as a prodromal symptom is sometime me observed). Most patients acquire
the disease after occupational exposure to pigs or pork products. Manifestation of disease in pigs is not a
prerequisite for infections in people in contact with pigs, since most animals are colonized by S. suis
without presenting clinical signs.
Clinical signs and symptoms
The incubation period ranges from a few hours to two days. In humans, S. suis usually produces a
purulent (with pus production) or non-purulent meningitis. In addition, endocarditis, cellulitis,
rhabdomyolysis (skeletal muscle breakdown), arthritis, pneumonia, and endopthalmitis (inner eye
inflammation) have also been reported. Arthritis affects various joints, including hips, elbows, wrists,
sacroiliac, spine, and thumb. In most cases, arthritis reflects generalized septicemia caused by S. suis.
Severe cases of sepsis with shock, multiple organ failure, disseminated intravascular coagulation, and
associated purpura fulminans (skin hemorrhages), which lead to death within hours, have also been
described. It has been demonstrated that S. suis has important inflammatory capacities. One of the most
striking features of the infection is the consequence of deafness following S. suis meningitis. The
deafness (unilateral or bilateral) has been mainly high tone and is frequently associated with vertigo.
Early administration of antibiotics does not appear to have any influence on subsequent hearing loss. No
cases of deafness have been reported in non-meningitis cases of human S. suis infection. Meningitis is
the most common presentation in humans however, many of the patients in Sichuan and Hong Kong
outbreaks , and almost all of the fatal cases, had typical symptoms of Streptococcal toxic shock syndrome
(STS)S with meningitis. To date, STSS has only been documented in patients infected with S. pyogenes,
another member of the Streptococcus family but very different from S. suis. However, the bacterium
isolates from the human and pig samples were clearly S. suis. Additional information is necessary to
determine whether the size and high mortality of the recent outbreak is because the Chinese S. suis
version is more virulent than other strains or due to the circumstances under which the Chinese patients
got infected and treated. Studies are under way to characterize the bacterial isolates from the outbreak in
detail. Streptococcus suis have also been identified as the most common cause of meningitis in Vietnam
and Thailand.
Prevention
The use of protective gloves when processing raw pork is recommended.
AKNOWLEDGE
This Guide is a compilation of documents published by Centers for Disease Control and Prevention
(CDC), International Society of Travel medicine International SOS, Mayo Clinic, Population and Health
Branch- Health Canada, Travel Med, Wikipedia, World Health Organization (WHO), Vaccine
Manufacturers, as well as opinion of physicians from Occucare International.
Since this Guide is made for educational purposes, the documents and illustrations from Wikipedia were
available under GNU Free Documentation License. We appreciate quality of information and work of
contributors and editors from Wikipedia.
AASince our knowledge of potential vaccine efficacy, adverse effects and contraindications changes
over the time, the Guide will be reviewed and updated quarterly. Please be aware of date of publication
when reading the Guide.
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This guide is for information only. The information provided herein should not be used for the diagnosis
or treatment of any medical condition. Any duplication or distribution of the information contained herein
is strictly prohibited.
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