|
Swine Flu & Bird
Flu - Influenza Information
All
Avian
Influenza (AI)
viruses are type A influenza viruses in the
virus family of Orthomyxoviridae and are subdivided into subtypes based
on hemagglutinin (H) and neuraminidase (N) protein spikes from the
central virus core. There are 16 H types, each with up to 9 N subtypes,
yielding a potential for 144 different H and N combinations. In
addition, all AI viruses fall into one of 2 pathotypes: low (LPAI) and
high (HPAI) pathogenicity, based on how dangerous to poultry.
Of the 16 H
types
known,
only
subtypes H5, H7 and H9 are known to be
capable of crossing the species barrier from birds to humans. It is
feared that if the avian influenza virus undergoes antigenic shift with
a human influenza virus, the new subtype created could be both highly
contagious and highly lethal in humans. Such a subtype could cause a
global influenza pandemic, similar to the Spanish Flu that killed over
20 million people in 1918 (though a variety of sources quote average
figures even higher, up to 100 million in some cases). Many health
experts are concerned that a virus that mutates to the point where it
can cross the species barrier (i.e. from birds to humans) will
inevitably mutate to the point where it can be transmitted from human
to human. It is at that point that a pandemic becomes likely.
Avian influenza in humans can be detected with standard influenza
tests. However, these tests have not always proved reliable. In March
2005, the World Health Organization announced that seven Vietnamese who
initially tested negative for bird flu were later found to have carried
the virus. All seven have since recovered from the disease. Currently
(6/05) the most reliable test (microneutralization) requires use of the
live virus to interact with antibodies from the patient's blood;
because live virus is required, for safety reasons the test can only be
done in a level 3 laborator
Home care will be the predominant mode of care for most people infected
with influenza. During the Novel Virus Alert Phase, individuals should
discuss with their health care provider specific recommendations for
both vaccination and chemoprophylaxis. This page is not medical advice,
but rather an inventory of issues to discussion with your health care
provider.
Most patients with pandemic influenza will be able to remain at home
during the course of their illness and can be cared for by other family
members or others who live in the household. Anyone residing in a
household with an influenza patient during the incubation period and
illness is at risk for developing influenza. A key objective in this
setting is to limit transmission of pandemic influenza within and
outside the home. When care is provided by a household member, basic
infection control precautions should be emphasized (e.g., segregating
the ill patient, hand hygiene). Infection within the household may be
minimized if a primary caregiver is designated, ideally someone who
does not have an underlying condition that places them at increased
risk of severe influenza disease. Although no studies have assessed the
use of masks at home to decrease the spread of infection, use of
surgical or procedure masks by the patient and/or caregiver during
interactions may be of benefit.
The disease is characterized by abrupt onset of constitutional and
respiratory symptoms, including fever, chills, muscle aches, headache,
malaise, nonproductive cough, sore throat, and runny nose. Upper
respiratory and constitutional symptoms tend to predominate in the
first several days of illness, but lower respiratory symptoms,
particularly cough, are common after the first week. In children,
nausea and vomiting and, occasionally, ear infection are also symptoms.
Since several other respiratory pathogens (including adenovirus,
respiratory syncytial virus, parainfluenza virus, rhinovirus,
coronavirus, human metapneumovirus, Mycoplasma pneumoniae and
Legionella) can also cause a similar clinical picture, definitive
diagnosis of influenza requires laboratory confirmation. However,
laboratory testing is not necessary for all patients. In the presence
of a community outbreak of respiratory illness, a presumptive diagnosis
can be made based on knowledge of the predominant agent causing the
outbreak.
Uncomplicated influenza gets better with or without treatment, but may
cause substantial discomfort and limitation of activity before getting
better.
Complications of influenza can include bacterial infections, viral
pneumonia, and cardiac and other organ system abnormalities. People
with chronic medical conditions may have increased risk of
complications when they get influenza. Many other diseases, including
serious infections such as rapidly progressive bacteremias, may start
with symptoms that resemble influenza and may need to be considered in
treatment decisions. Many people with uncomplicated influenza use
over-the-counter medicines to help lessen their symptoms.
Here are some tips to keep from spreading your germs to others, and to
keep from catching someone else’s germs.
Keep your germs to yourself:
§
Cover your nose and mouth with a tissue when sneezing, coughing or
blowing your nose.
§
Throw out used tissues in the trash as soon as you can.
§
Always wash your hands after sneezing, blowing your nose, or coughing,
or after touching used tissues or handkerchiefs. Wash hands often if
you are sick.
§
Use warm water and soap or alcohol-based hand sanitizers to wash your
hands.
§
Try to stay home if you have a cough and fever.
§
See your doctor as soon as you can if you have a cough and fever, and
follow their instructions, including taking medicine as prescribed and
getting lots of rest.
§
If asked to, use face masks provided in your doctor’s office
or
clinic’s waiting room; follow their instructions to help stop
the
spread of germs.
Keep the germs away:
§
Wash your hands before eating, or touching your eyes, nose or mouth.
§
Wash your hands after touching anyone else who is sneezing, coughing,
blowing their nose, or whose nose is running.
§
Don’t share things like cigarettes, towels, lipstick, toys,
or
anything else that might be contaminated with respiratory germs.
§
Don’t share food, utensils or beverage containers with others.
Plan Ahead
People should plan ahead and think about what they need to have in
their house in case someone in their household were to become infected
with influenza and need to receive care at home. If you live alone, are
a single parent of young children, or are sole caregiver for a frail or
disabled adult, it would be a good idea to have some items stored in
your home in case of illness:
· Have enough fluids (e.g. water, juice, soup)
available to last for 2 weeks.
· Have enough basic household items (e.g. tissues)
to last for 2 weeks.
· Have acetaminophen and a thermometer in the
medicine
cabinet. Do you know how to use/read a thermometer correctly? If not,
ask someone to show you how.
· Think of someone you could call upon for help if
you
became very ill with the flu and discuss this possibility with him or
her.
· Think of someone you could call upon to care for
your
children if you were required to work and their school or day care was
closed because of the influenza pandemic; discuss the possibility with
them.
Infection Control Measures in the Home
· All persons in the household should carefully
follow
recommendations for hand hygiene (i.e., handwashing with soap and water
or use of an alcohol-based hand rub) after contact with an influenza
patient or the environment in which care is provided.
· Although no studies have assessed the use of
masks at
home to decrease the spread of infection, use of surgical or procedure
masks by the patient and/or caregiver during interactions may be of
benefit. The wearing of gloves and gowns is not recommended for
household members providing care in the home.
· Soiled dishes and eating utensils should be
washed
either in a dishwasher or by hand with warm water and soap. Separation
of eating utensils for use by a patient with influenza is not necessary.
· Laundry can be washed in a standard washing
machine with
warm or cold water and detergent. It is not necessary to separate
soiled linen and laundry used by a patient with influenza from other
household laundry. Care should be used when handling soiled laundry
(i.e., avoid “hugging” the laundry) to avoid
contamination.
Hand hygiene should be performed after handling soiled laundry.
· Tissues used by the ill patient should be placed
in a
bag and disposed with other household waste. Consider placing a bag for
this purpose at the bedside.
· Normal cleaning of environmental surfaces in the
home should be followed.
Management of Well Persons in the Home
· Persons who have not been exposed to pandemic
influenza
and who are not essential for patient care or support should not enter
the home while persons are actively ill with pandemic influenza.
· If unexposed persons must enter the home, they
should avoid close contact with the patient.
· Persons living in the home with the pandemic
influenza
patient should limit contact with the patient to the extent possible;
consider designating one person as the primary care provider.
· Household members should monitor closely for the
development of influenza symptoms and contact a telephone hotline or
medical care provider if symptoms occur.
Management of Influenza Patients
Persons who have a sudden onset of influenza-like symptoms (e.g.
headache, fever, chills, cough, chest pain, sore throat, muscle aches,
weakness, exhaustion) should do the following:
· Remain at home at least until all symptoms have
resolved (approximately 4-5 days)
· Take medication as needed to relieve the
symptoms of the flu.
§
Decongestants, such as phenylephrine, and pseudoephedrine, produce a
narrowing of blood vessels. This leads to clearing of nasal congestion,
but it may also cause an increase in blood pressure in patients who
have high blood pressure. OTC drugs to relieve stuffy noses often
contain more than one ingredient. Some of these products are marketed
for allergy relief and others for colds. They usually contain both an
antihistamine and a nasal decongestant. The decongestant ingredient
unstuffs nasal passages; antihistamines dry up a runny nose. But some
of these products may also contain aspirin or acetaminophen, and some
contain a decongestant alone. Closely related products with similar
names may have different ingredients. There are other medications in
the form of nasal drops and sprays sold OTC for this purpose. As with
pills, some of these are long acting (up to 12 hours) and some are
shorter acting. And, as with pills, most have some side effects. Many
of the products contain a nasal decongestant such as oxymetazoline or
phenylephrine. When used for more than three days or more often than
directed by the label, these drops or sprays can sometimes cause a
"rebound" effect, in which the nose gets more stuffy. Other nose drops
and sprays are formulated with a saline (salt) solution and can be used
for dry nose or to relieve clogged nasal passages.
§
Dextromethorphan, an antitussive, is used to relieve a nonproductive
cough caused by a cold, the flu, or other conditions. Dextromethorphan
comes as a liquid or as a lozenge to take by mouth. It is usually taken
every 4-8 hours as needed. Do not take more than 120 mg of
dextromethorphan in a 24-hour period. Refer to the package or
prescription label to determine the amount contained in each dose. The
lozenge should dissolve slowly in your mouth. Drink plenty of water
after taking a dose. Follow the directions on the package or
prescription label carefully, and ask your doctor or pharmacist to
explain any part you do not understand.
§
Antipyretics are fever-reducing medications; the term comes from the
Greek word pyresis, which means fire. Ibuprofen (Motrin) and
acetaminophen (Tylenol) are generally recognized as safe and effective
single analgesic-antipyretic active ingredients. These two antipyretics
can be taken together or on an alternating 4 hour schedule. Ibuprofen
provides greater temperature decrement and longer duration of
antipyresis than acetaminophen when the two drugs are administered in
approximately equal doses.
§
Never give aspirin to children or teenagers who have flu-like symptoms
(and particularly fever) without first speaking to your doctor. Giving
aspirin to children and teenagers who have influenza can cause a rare
but serious illness called Reye syndrome. Reading the label becomes
especially important when it comes to products containing aspirin
(acetylsalicylic acid) or their chemical cousins, other salicylates,
which are used to reduce fever or treat headaches and other pain.
§
A person's fluid needs are greater when that person has fever. Drink
lots of fluids (water and other non-alcoholic, non-caffeinated
beverages) to avoid becoming dehydrated. Start with sips of any fluid
other than caffeinated beverages. Drinking too much fluid at once can
bring on more vomiting.
Electrolyte solutions available in drugstores are usually
best.
Sport drinks contain a lot of sugar and can cause or worsen diarrhea.
§
If you have diarrhea, it's a good idea to rest, eat only small amounts
of food at a time, and drink plenty of fluids to prevent dehydration.
Avoid over-the-counter diarrheal medications unless specifically
instructed to use one by your doctor. Certain infections can be made
worse by these drugs.
When you have diarrhea, your body is trying to get rid of
whatever food, virus, or other bug is causing it. OTC products marketed
to stop diarrhea may contain loperamide (Imodium A-D), or attapulgite
(Diasorb, Kaopectate and others), or bismuth subsalicylate
(Pepto-Bismol and others).
· Use either a traditional glass thermometer for
each
person [don't cross-contaminate patients], or a digital thermometer
with lots of disposable sleeves. The thermometers are a few dollars.
The sleeves are a dollar or so per hundred.
· Get plenty of bed rest
· Do not smoke
· Restrict visitors to their home
· Cover mouth and nose with a tissue when coughing
or sneezing.
· Keep at least 3 feet away from others.
· Patients should not leave the home during the
period
when they are most likely to be infectious to others (i.e., 5 days
after onset of symptoms). When movement outside the home is necessary
(e.g., for medical care), the patient should follow cough etiquette
(i.e., cover the mouth and nose when coughing and sneezing) and wear
procedure or surgical masks if available.
To protect the patients infected with influenza, individuals having
contact with the patient, and the community in general, certain
infection control measures should be practiced:
· Wash hands often with warm soap and water,
scrubbing for 15-20 seconds
· Family members should wash hands or use
waterless hand sanitizer after contact with the patient
· Do not share eating utensils or drinks
· Do not rub eyes, touch nose or mouth
· Patients should cover their mouths and noses
with tissue
when coughing or sneezing, dispose of used tissues immediately after
use and wash hands after using tissues
· In general, wearing goggles or a face shield for
routine
contact with patients with pandemic influenza is not necessary. If
sprays or splatter of infectious material is likely, goggles or a face
shield should be worn as recommended for standard precautions.
· In the absence of visible soiling of hands,
approved
alcohol-based products for hand disinfection are preferred over
antimicrobial or plain soap and water because of their superior
microbiocidal activity, reduced drying of the skin, and convenience.
· Physically separate the patient with influenza
from non-ill persons living in the home as much as possible.
In a pandemic influenza event, some individuals who are cared for at
home may develop complications. Should complications develop, these
individuals should seek medical care immediately, either by calling the
doctor or going to an emergency room. Upon arrival, the receptionist or
nurse should be told about the symptoms so that precautions can be
taken (providing a mask and or separate area for triage and evaluation).
Warning Signs to seek urgent medical care:
In children, these include:
1. High or prolonged fever for more than 4-5 days
2. Fast breathing or trouble breathing
3. Bluish skin color
4. Not drinking enough fluids
5. Changes in mental status, somnolence, irritability
6. Seizures, confusion or seizures
7. Influenza-like symptoms improve but then return with fever and worse
cough
8. Worsening of underlying chronic medical conditions (for example,
heart or lung disease, diabetes)
9. Cough becomes productive of yellow sputum
"The flu may not kill you … what may kill you is
dehydration(uttørkning) from vomiting, from diarrhea, from
sweating, from feeling too darned weak to fix a cup of soup, from fever
denaturing the proteins in your brain (happens somewhere around 105
degrees Farenheit, 40.5 degrees Celcius)."
Given that media reports on the potential avian flu pandemic have been
sparse, misleadingly optimistic or simply non-existent, many people are
unaware of the threat of the H5N1 virus currently spreading through
Asia and Russia. However, considerable information regarding avian
influenza is available on the internet if you look for it. While
newspaper headlines scream warnings of possible terrorist attacks, a
more serious and much more likely threat is looming just over the
horizon. And world health leaders and scientists are taking notice. A
number of websites have been created to assist health professionals
monitor and share information on H5N1, offering references to media
stories, scientific reports and personal commentary on a serious
situation that is evolving on a daily basis. The message these sites
contain is simple: the threat of a severe avian flu pandemic is real
and not enough is being done to prepare for it. You have a
choice: you can hide your head in the sand and hope that
nothing happens, or if it does, your local/state/national government
will take care of you and your family; or you can consider the
possibility that a severe pandemic may be only months away and begin
planning for your family's safety and comfort NOW. Perhaps
the references listed below will help you choose.
Stages of a pandemic
The World Health Organization (WHO) has developed a global influenza
preparedness plan, which defines the stages of a pandemic, outlines
WHO's role and makes recommendations for national measures before and
during a pandemic.
As of early August 2005, most sources place the current avian influenza
epidemic at phase 3. There is ongoing debate as to the current phase.
As of late September 2005 consensus had not been reached on what the
current phase should be considered (between 3-5) based on the ongoing
outbreaks in multiple countries of southeast asia. The phases are
defined as:
Interpandemic period
Phase 1: No new influenza virus subtypes have been detected in humans.
An influenza virus subtype that has caused human infection may be
present in animals. If present in animals, the risk of human infection
or disease is considered to be low.
Phase 2: No new influenza virus subtypes have been detected in humans.
However, a circulating animal influenza virus subtype poses a
substantial risk of human disease.
Pandemic alert period
Phase 3: Human infection(s) with a new subtype, but no human-to-human
spread, or at most rare instances of spread to a close contact.
Phase 4: Small cluster(s) with limited human-to-human transmission but
spread is highly localized, suggesting that the virus is not well
adapted to humans.
Phase 5: Larger cluster(s) but human-to-human spread still localized,
suggesting that the virus is becoming increasingly better adapted to
humans, but may not yet be fully transmissible (substantial pandemic
risk).
Pandemic period
Phase 6: Pandemic: increased and sustained transmission in general
population.
Notes
The distinction between phase 1 and phase 2 is based on the risk of
human infection or disease resulting from circulating strains in
animals. The distinction is based on various factors and their relative
importance according to current scientific knowledge. Factors may
include pathogenicity in animals and humans, occurrence in domesticated
animals and livestock or only in wildlife, whether the virus is
enzootic or epizootic, geographically localized or widespread, and/or
other scientific parameters.
The distinction between phase 3, phase 4 and phase 5 is based on an
assessment of the risk of a pandemic. Various factors and their
relative importance according to current scientific knowledge may be
considered. Factors may include rate of transmission, geographical
location and spread, severity of illness, presence of genes from human
strains (if derived from an animal strain), and/or other scientific
parameters.
The pandemic stage 6 may be marked by two or more waves. For example,
the initial wave of the Spanish Influenza pandemic of 1918 killed a few
but was mild enough in its effects to receive the dismissive nickname
of the "three day flu." But the second wave which hit North America a
few months later in the summer of 1918 was lethal. Apparently in the
interim the novel H1N1 pandemic strain had added the gene or genes that
made the final wave a killer. Perhaps the effects of the lethal second
wave would have been even more devastating if the innocuous first wave
had not already passed through the population, leaving in its wake at
least some immune response to the H1N1 antigens that were present in
both waves.
Avian Influenza
Reading WHO
- WHO
(Writing
Committee of
WHO
Consultation on
Human Influenza A/H5). Avian influenza A (H5N1)
infection
in humans. N Engl J Med 2005 Sep 29;353(13):1374-85
[Full text]
- WHO.
Assessment
of
risk to human
health associated with
outbreaks of highly pathogenic H5N1 avian
influenza in
poultry. May 14 [Full text]
- WHO.
Avian
influenza
and the
pandemic threat in Africa:
risk assessment for Africa. Oct 28, 2005 [Full text]
- WHO.
Avian
influenza.
Fact
sheet. Jan 15, 2004 [Web
page]
- WHO.
Avian
influenza:
assessing
the pandemic threat.
Jan 2005 [Full text]
- WHO.
Evolution
of
H5N1 avian
influenza viruses in Asia.
Emerg Infect Dis 2005 Oct;11(10) [Full text]
- WHO.
Guidelines
for
the use of
seasonal influenza vaccine in
humans at risk of H5N1 infection.
Published Jan 30, 2004
[Web page]
- WHO.
Laboratory
study
of H5N1
viruses in domestic ducks:
main findings. Oct 29, 2004 [Full text - Summary
of upcoming research]
- WHO.
Recommended
laboratory
tests to identify influenza
A/H5 virus in specimens from patients with
an influenza-like
illness. Feb 19, 2004 [Full text]
- WHO.
Responding
to
the avian
influenza pandemic threat:
recommended strategic actions. Released Sep
2, 2005 [Full text]
- WHO.
WHO
guidance on
public
health measures in countries
experiencing their first outbreaks of H5N1
avian influenza.
Oct 2005 [Full text]
|
