Avian Influenza (H7N9) is a virus that is known to affect birds.
It is caused by infection with the viruses of Orthomyxoviridae family. Avian
Influenza is the only known natural virus of orthomyxoviruses family known
affect birds. A vast majority of bird species are known to susceptible to
infection from this viruses. It is also known that aquatic birds are mostly
affected with this virus. In the past, it was considered that humans and
animals are immune to this virus but a recent study suggests otherwise. The
prominent reason for this virus affecting the human population is direct or
close contact with the infected bird population. Though, no deaths have been
confirmed yet, but a study suggests that this virus is capable of making humans
fall ill. The range of illness varies from being mild to severe.
It is caused by infection with the viruses of Orthomyxoviridae family. Avian
Influenza is the only known natural virus of orthomyxoviruses family known
affect birds. A vast majority of bird species are known to susceptible to
infection from this viruses. It is also known that aquatic birds are mostly
affected with this virus. In the past, it was considered that humans and
animals are immune to this virus but a recent study suggests otherwise. The
prominent reason for this virus affecting the human population is direct or
close contact with the infected bird population. Though, no deaths have been
confirmed yet, but a study suggests that this virus is capable of making humans
fall ill. The range of illness varies from being mild to severe.
Signs and Symptoms
There are two types of virus in this category Low Pathogenic Avian
Influenza and High Pathogenic Avian Influenza.
The known signs and symptoms of Low Pathogenic Avian Influenza vary
according to a person’s immune system. In most human cases, this virus(LPAI)
cause conjunctivitis or mild illness similar to those when affected by influenza namely mild fever, sore throat, cough. But LPAI virus is also capable of causing
respiratory diseases like pneumonia that require immediate treatment and
hospitalization. The effects of Highly Pathogenic Avian Influenza (HPAI) in
humans and animals is similar to that of LPAI causes conjunctivitis and
influenza. They mostly affect and cause respiratory illness like breathing
difficulty, shortness of breath, acute respiratory distress, pneumonia,
respiratory failure and viral pneumonia along with multi-organ disease which
are accompanied by abdominal pain, nausea, vomiting, diarrhea and neurologic
changes. LPAI H7N9 and HPAI H5N1 are cause of most human illnesses. Though
there are very few reported cases of death but most of the cases confirm its
association with serious illnesses.
Influenza and High Pathogenic Avian Influenza.
The known signs and symptoms of Low Pathogenic Avian Influenza vary
according to a person’s immune system. In most human cases, this virus(LPAI)
cause conjunctivitis or mild illness similar to those when affected by influenza namely mild fever, sore throat, cough. But LPAI virus is also capable of causing
respiratory diseases like pneumonia that require immediate treatment and
hospitalization. The effects of Highly Pathogenic Avian Influenza (HPAI) in
humans and animals is similar to that of LPAI causes conjunctivitis and
influenza. They mostly affect and cause respiratory illness like breathing
difficulty, shortness of breath, acute respiratory distress, pneumonia,
respiratory failure and viral pneumonia along with multi-organ disease which
are accompanied by abdominal pain, nausea, vomiting, diarrhea and neurologic
changes. LPAI H7N9 and HPAI H5N1 are cause of most human illnesses. Though
there are very few reported cases of death but most of the cases confirm its
association with serious illnesses.
Detection in Humans
Avian influenza cannot be detected in humans on the basis of signs
and symptoms alone. To find out whether a person is suffering from Avian
influenza laboratory testing is vital. For successful diagnosis of Avian
influenza, swab from the patient’s nose or throat is collected and tested in
the laboratory. The disease can adversely affect patient’s health, in case of
wrong diagnosis during initial treatment. In the lab, avian influenza is
determined by the result of the molecular test performed on patient’s swab. The
other way to detect avian influenza is by artificially growing the virus in the
laboratory, but for that a very high level of precautions is necessary.
and symptoms alone. To find out whether a person is suffering from Avian
influenza laboratory testing is vital. For successful diagnosis of Avian
influenza, swab from the patient’s nose or throat is collected and tested in
the laboratory. The disease can adversely affect patient’s health, in case of
wrong diagnosis during initial treatment. In the lab, avian influenza is
determined by the result of the molecular test performed on patient’s swab. The
other way to detect avian influenza is by artificially growing the virus in the
laboratory, but for that a very high level of precautions is necessary.
Patients who are critically ill, lower respiratory tract specimens
are collected and tested in the laboratory that leads correct diagnosis of
avian influenza. Among patients who have recovered from their sickness due to
their strong immune system, it is very difficult to detect the infection of
avian influenza. For such patients, it is possible to detect avian influenza
but the process is very tedious and the results are not hundred percent
correct. In the process, the body’s response is noted for other viruses and infection.
are collected and tested in the laboratory that leads correct diagnosis of
avian influenza. Among patients who have recovered from their sickness due to
their strong immune system, it is very difficult to detect the infection of
avian influenza. For such patients, it is possible to detect avian influenza
but the process is very tedious and the results are not hundred percent
correct. In the process, the body’s response is noted for other viruses and infection.
The kind of antibodies the
body’s immune system has produced is also taken into consideration before
concluding whether the person was affected by avian influenza or not. This
process requires blood specimens from the first week of illness which is a rare
probability. It also takes several weeks for the results to present a clear
picture. Moreover, these tests cannot be conducted in any normal laboratory.
body’s immune system has produced is also taken into consideration before
concluding whether the person was affected by avian influenza or not. This
process requires blood specimens from the first week of illness which is a rare
probability. It also takes several weeks for the results to present a clear
picture. Moreover, these tests cannot be conducted in any normal laboratory.
There are various guidelines and instructions declared by the government
to detect and possible mode of treatment to be undertaken by any medical
practitioner for timely treatment of Avian influenza (H7N9).
to detect and possible mode of treatment to be undertaken by any medical
practitioner for timely treatment of Avian influenza (H7N9).
Auther : Dr. B. Cory Harow is an emergency medicine doctor in
Boynton Beach, Florida. He received his medical degree from Stony Brook
University School of Medicine and has been in practice for 16 years.
Boynton Beach, Florida. He received his medical degree from Stony Brook
University School of Medicine and has been in practice for 16 years.
