Shiloh
Editor, Senior Moderator
Source: http://www.intramed.net/contenidover.asp?contenidoID=60000
Google translation:
27 MAY 09 | swine influenza in humans in the U.S., 2005-2009
Description of 11 cases of infection with influenza virus A (H1)
We describe the clinical characteristics and epdiemiol?gicas of the first 11 cases of infection with the triple mixture of recombinant influenza A (H1), as confirmed by laboratory.
Drs. Shinde V, Bridges CB, Uyek TM, et al.
N Engl J Med 2009; 361.
Introduction
It is believed that the pig is a test tube to mix stable recombinant virus avian, pig and human influenza strains capable of producing that can generate pandemics. Between 1930 and 1990, the most common viruses circulating in pigs was the classic swine influenza A (H1N1) that had minimal changes.
However, in late 1990, there were a number of strains and subtypes (H1N1, H3N2 and H1N2) triple stable recombinant swine influenza virus A (H1), whose genome includes combinations of gene segments of swine influenza virus, human avian and swine herds in North America.
Before 2005, the Centers for Disease Control and Prevention (CDC), received one or two reports of human infection with the classical swine flu virus. In 2005, the CDC in the United States identified the first human infection with the triple recombinant stable swine influenza A (H1). From December 2005 to February 2009, CDC received 11 reports of human infection with the triple recombinant stable swine influenza A (H1).
In this article the authors describe the epidemiological and clinical characteristics of these 11 cases.
Methods
Monitoring, reporting and data collection. The demographic and clinical information of the first 3 patients were obtained before 2007, the year that a new human infection with influenza A virus became identifiable and began a systematic collection of information.
As part of the information you send a monitoring report that includes the following:
*
Demographic characteristics.
*
Associated chronic diseases.
*
Level of vaccination against seasonal influenza.
*
Clinical signs and symptoms.
*
Results of diagnostic tests for influenza.
*
Antiviral treatment.
*
Abnormal laboratory results.
*
Evolution.
*
Exposure to pigs and other animals.
All this information was sent to CDC in this way.
Laboratory confirmation.
All patients in this series were taken samples of material during the respiratory disease. In all but one patient was able to make the diagnosis of infection with influenza A virus that is typified by the chain reaction of reverse transcriptase polymerase (RT-PCR). 7 The patient's specimen tested positive for influenza A (H1N2).
Samples that could not be sent to subtipificadas Division of CDC influenza laboratory for new identification and sequence. At the CDC, were confirmed by using RT-PCR in real time and test the inhibition of haemagglutination. Investigated the mixture of stable recombinant virus avian, pig and human influenza
With special techniques are established susceptibility to antiviral agents adamantine (amantadine and rimantadine) and oseltamivir and zanamivir.
Results
The average age of patients was 10 years (16 months to 48 years) and 64% were men. Patient 3 was part of a family of 3 other members with suspected infection (not confirmed) of swine influenza virus. All patients lived in the Midwest of the United States.
In most cases there was direct contact with pigs or approximation at exhibitions, fairs or farms. One patient ignored the type of contact and one patient had contact with a person suspected of having flu by coming in contact with pigs. This report suggests that transmission between humans is limited.
The median incubation period was 3.5 days (3 to 9 days).
Regarding the clinical features were observed:
*
Four of the 11 patients had comorbidities (asthma, low nonspecific immune defenses and eczema).
*
Three patients received antiviral seasonal vaccine.
*
Of the 10 patients who obtained clinical symptoms were:
Fever (9 patients).
Cough (10 patients).
Headache (6 patients).
Sore Throat (6 patients).
Diarrhea (3 patients)
Myalgia, vomiting and dyspnea (2 patients)
Conjunctivitis (1 patient).
The mean fever was 39.7 ? C and 4 patients required hospitalization. In 2 patients the disease was severe and require prolonged mechanical ventilation. One of the patients had an infection by Pseudomonas aggregated and evolved favorably with broad spectrum antibiotics and oseltamivir.
A patient of 26 years of age he was due to pneumonia and sepsis and required mechanical ventilation and inotropic cardiac medication for hypotension. After 30 days of hospitalization and treatment with broad spectrum antibiotics and oseltamivir, were discharged.
The 11 patients, including hospitalized, recovered favorably. Laboratory studies led to finding a common patient had leukopenia and thrombocytopenia.
The CDC confirmed that all patients had stable mixtures of recombinant virus A (H1) poultry, pig and human influenza. Ten of the 11 patients were infected with the H1N1 subtype and the remaining patient with the H1N2 subtype.
All the viruses isolated in this series were susceptible to adamantine (amantadine and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir).
Discussion
In this report, the authors describe the clinical characteristics and epdiemiol?gicas of 11 cases of infection with the triple mixture of recombinant influenza A (H1), as confirmed by laboratory. These cases were reported in the United States before the current epidemic of procina influenza A (H1N1).
The exposure of patients to their environment or pigs varied widely and almost half of patients unable to have direct contact with these animals.
The median incubation period was 3.5 days (3 to 9) and was generally longer than the incubation period for seasonal influenza.
The most frequent symptoms and signs are not differentiated from the common flu, but in some cases were severe categories of disease of the airways that are uncommon in the common flu.
Although all patients recovered, the spectrum of severity was wide. The favorable evolution of patients was due to the improvement in viral surveillance, the ability to implement specific methods of diagnosis and early treatment and proper.
The phylogenetic information further indicates that a lineage of triple mixture of recombinant influenza A (H1) is responsible for epidemics in the United States unleashed and Mexico.
Must take special precautions in areas where pigs abound.
The above shows that the possibility of a pandemic is a real threat and therefore, during interpandemia, all human infections by swine flu virus, even those that seem minor, they deserve a full investigation to establish the risks clinical and epidemiological human beings.
♦ Review and summary: Dr. Ricardo Ferreira
Google translation:
27 MAY 09 | swine influenza in humans in the U.S., 2005-2009
Description of 11 cases of infection with influenza virus A (H1)
We describe the clinical characteristics and epdiemiol?gicas of the first 11 cases of infection with the triple mixture of recombinant influenza A (H1), as confirmed by laboratory.
Drs. Shinde V, Bridges CB, Uyek TM, et al.
N Engl J Med 2009; 361.
Introduction
It is believed that the pig is a test tube to mix stable recombinant virus avian, pig and human influenza strains capable of producing that can generate pandemics. Between 1930 and 1990, the most common viruses circulating in pigs was the classic swine influenza A (H1N1) that had minimal changes.
However, in late 1990, there were a number of strains and subtypes (H1N1, H3N2 and H1N2) triple stable recombinant swine influenza virus A (H1), whose genome includes combinations of gene segments of swine influenza virus, human avian and swine herds in North America.
Before 2005, the Centers for Disease Control and Prevention (CDC), received one or two reports of human infection with the classical swine flu virus. In 2005, the CDC in the United States identified the first human infection with the triple recombinant stable swine influenza A (H1). From December 2005 to February 2009, CDC received 11 reports of human infection with the triple recombinant stable swine influenza A (H1).
In this article the authors describe the epidemiological and clinical characteristics of these 11 cases.
Methods
Monitoring, reporting and data collection. The demographic and clinical information of the first 3 patients were obtained before 2007, the year that a new human infection with influenza A virus became identifiable and began a systematic collection of information.
As part of the information you send a monitoring report that includes the following:
*
Demographic characteristics.
*
Associated chronic diseases.
*
Level of vaccination against seasonal influenza.
*
Clinical signs and symptoms.
*
Results of diagnostic tests for influenza.
*
Antiviral treatment.
*
Abnormal laboratory results.
*
Evolution.
*
Exposure to pigs and other animals.
All this information was sent to CDC in this way.
Laboratory confirmation.
All patients in this series were taken samples of material during the respiratory disease. In all but one patient was able to make the diagnosis of infection with influenza A virus that is typified by the chain reaction of reverse transcriptase polymerase (RT-PCR). 7 The patient's specimen tested positive for influenza A (H1N2).
Samples that could not be sent to subtipificadas Division of CDC influenza laboratory for new identification and sequence. At the CDC, were confirmed by using RT-PCR in real time and test the inhibition of haemagglutination. Investigated the mixture of stable recombinant virus avian, pig and human influenza
With special techniques are established susceptibility to antiviral agents adamantine (amantadine and rimantadine) and oseltamivir and zanamivir.
Results
The average age of patients was 10 years (16 months to 48 years) and 64% were men. Patient 3 was part of a family of 3 other members with suspected infection (not confirmed) of swine influenza virus. All patients lived in the Midwest of the United States.
In most cases there was direct contact with pigs or approximation at exhibitions, fairs or farms. One patient ignored the type of contact and one patient had contact with a person suspected of having flu by coming in contact with pigs. This report suggests that transmission between humans is limited.
The median incubation period was 3.5 days (3 to 9 days).
Regarding the clinical features were observed:
*
Four of the 11 patients had comorbidities (asthma, low nonspecific immune defenses and eczema).
*
Three patients received antiviral seasonal vaccine.
*
Of the 10 patients who obtained clinical symptoms were:
Fever (9 patients).
Cough (10 patients).
Headache (6 patients).
Sore Throat (6 patients).
Diarrhea (3 patients)
Myalgia, vomiting and dyspnea (2 patients)
Conjunctivitis (1 patient).
The mean fever was 39.7 ? C and 4 patients required hospitalization. In 2 patients the disease was severe and require prolonged mechanical ventilation. One of the patients had an infection by Pseudomonas aggregated and evolved favorably with broad spectrum antibiotics and oseltamivir.
A patient of 26 years of age he was due to pneumonia and sepsis and required mechanical ventilation and inotropic cardiac medication for hypotension. After 30 days of hospitalization and treatment with broad spectrum antibiotics and oseltamivir, were discharged.
The 11 patients, including hospitalized, recovered favorably. Laboratory studies led to finding a common patient had leukopenia and thrombocytopenia.
The CDC confirmed that all patients had stable mixtures of recombinant virus A (H1) poultry, pig and human influenza. Ten of the 11 patients were infected with the H1N1 subtype and the remaining patient with the H1N2 subtype.
All the viruses isolated in this series were susceptible to adamantine (amantadine and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir).
Discussion
In this report, the authors describe the clinical characteristics and epdiemiol?gicas of 11 cases of infection with the triple mixture of recombinant influenza A (H1), as confirmed by laboratory. These cases were reported in the United States before the current epidemic of procina influenza A (H1N1).
The exposure of patients to their environment or pigs varied widely and almost half of patients unable to have direct contact with these animals.
The median incubation period was 3.5 days (3 to 9) and was generally longer than the incubation period for seasonal influenza.
The most frequent symptoms and signs are not differentiated from the common flu, but in some cases were severe categories of disease of the airways that are uncommon in the common flu.
Although all patients recovered, the spectrum of severity was wide. The favorable evolution of patients was due to the improvement in viral surveillance, the ability to implement specific methods of diagnosis and early treatment and proper.
The phylogenetic information further indicates that a lineage of triple mixture of recombinant influenza A (H1) is responsible for epidemics in the United States unleashed and Mexico.
Must take special precautions in areas where pigs abound.
The above shows that the possibility of a pandemic is a real threat and therefore, during interpandemia, all human infections by swine flu virus, even those that seem minor, they deserve a full investigation to establish the risks clinical and epidemiological human beings.
♦ Review and summary: Dr. Ricardo Ferreira