Monday, February 20, 2017

Taiwan CDC: January's Imported H7N9 Case Carried HPAI Mutation

Taiwan in relation to China


While its ultimate impact and importance are far from certain, the `big' avian flu story over the weekend was the announcement from Guangdong Province's CDC of  Two H7N9 `Variants' Isolated From Human Cases.  Also detected in local poultry, these variant viruses appear to have acquired the HA genetic markers that change them from low path (LPAI) to high (HPAI) in birds. 

Unlike all of the other avian flu viruses we are following, H7N9 is the only LPAI virus (essentially benign in birds) that can cause serious - even fatal - illness in humans. 

Today Taiwan's CDC is announcing that their 5th imported H7N9 case from late January (see Taiwan CDC Announces An Imported H7N9 Case)- who remains hospitalized in critical condition - carried a virus with similar changes to its HA gene.  A case they described as `. . . . a 69-year-old man with a history of contact in Yangjiang, Guangdong Province, China, with no bird or suspected history of illness.'

Additionally, Taiwan reports his infection shows signs of antiviral resistance (Tamiflu (c) & Relenza (c)), although this may have been the result of a `spontaneous' mutation in the patient while undergoing treatment.

So far, these reported changes to the HA gene only appear to affect its pathogenicity in birds, and we've seen no indication that it increases the risk to humans.   The caveat being, information is often slow to come out of China and it is impossible to predict where this variant's evolutionary path will ultimately take it. 

Meanwhile, this third human case from Guangdong Province suggests this new variant may be biologically `fit' enough to have some `legs'.  Epidemiologists are no doubt scrambling to determine the size and scope of its spread.

Mutations occur constantly in flu viruses, but only rarely do they convey a significant evolutionary advantage. Most are neutral, or even detrimental to the virus's survival. While it is too soon to predict how this one will impact H7N9's course, no one is taking it lightly.

This (translated) announcement from Taiwan's CDC.

UNDCP continues to monitor the international H7N9 flu epidemic and virus epidemics, the people to the Chinese mainland should be vigilant, not near birds and personal hygiene protection measures

The Illness Control Agency on February 13 from February 4 this year, the first confirmed H7N9 outside the case moved to the case of the successful separation of the virus, and on February 15 to complete the whole gene sequence analysis, the relevant sequence message was on February 16 to provide farmers The committee was regularly distributed to the global GISAID website to share with the world, and today the meeting was confirmed by the Expert Advisory Committee on Influenza Advisory Committee.
The results showed that the H7N9 influenza virus was isolated from the case, and its erythrocyte lectin (HA) and neuraminidase (NA) protein gene were similar to H7N9 influenza virus isolated from China. Other internal protein gene combinations Compared with the current virus is slightly different, may be a new genotype, the birds with high pathogenicity, but no enhancement of birds or human transmission ability of the mutation.

The Agency has said that the addition of three basic amino acids to the H7N9 virus isolated from the case of the HA protein cleavage may improve its pathogenicity in poultry. In addition, further gene sequence analysis showed that the NA protein of the virus has a mutation, anti-viral agents such as influenza and Ruileansa drug resistance, experts speculate that the treatment process may be selected from the drug resistance virus. 

The Department of Health (DH) immediately informed the care team as a treatment reference when the virus resistance was detected on February 15, and the current case is still in serious hospitalization. UNDCP and COA will keep abreast of trends in the international human and bird H7N9 virus epidemic strains, strengthen immediate epidemic surveillance and virus surveillance, and today announced the update of the new clinical guidelines for influenza A influenza A to ensure that people health.

In the near future, the first case of domestic H7N9 outside the case into the case of epidemic prevention and other concerns, the Commission reiterated that the case on January 25 entry to Taiwan, the first time that is due to fever by the airport quarantine officers to seize and open medical advice orders recommended medical treatment , The case on the same day medical treatment and the next day to a medical center when the doctor suspected H7N9 flu mild, and immediately informed the seizure, indicating that the quarantine station or physician have a high degree of vigilance and good monitoring responsibility, no delay notification or misdiagnosis situation. In addition, the health unit is also active in daily understanding of the case; the other case after the diagnosis, that is, all relevant contacts to investigate and book, for close contacts are given appropriate health education and open independent health notice. The total number of contacts related to a total of 141 people, were on February 13 to lift the tube.

According to the World Health Organization in April 2013 issued by the epidemic news ( content, the first batch of Chinese mainland H7N9 cases in Shanghai 2 cases, 1 case of Anhui, 3 people between the onset time Between 19 February and 15 March 2013, all cases developed severe pneumonia. These cases until March 29 to obtain the Chinese Center for Disease Control and Prevention laboratory confirmed H7N9 flu, from the onset to the diagnosis of up to 13 to 38 days. It is not true that the World H7N9 first appeared in Shanghai, where the local medical institutions confirmed and completed the virus.

China has accumulated 426 cases of H7N9 flu cases since the beginning of this season (October 1, 2016), has exceeded the calendar year, the number of cases in Jiangsu Province, 124 cases, 75 cases of Zhejiang Province, Guangdong Province, 47 cases and 45 cases of Anhui Province Many cases of poultry, live poultry market exposure history, to more than 50 years of age groups. Global cumulative since 2013, 1,224 cases, the World Health Organization (WHO) update as of January 16 this year, cumulative 359 deaths.

At present, China is still at the peak of H7N9 flu, people need to go to be vigilant, and should comply with the "5 to 6 no" principle, "5 to": poultry and eggs to cooked food, to wash the bottom of soap, To wear a mask for medical treatment and to inform the occupation and contact history, long-term contact with birds to be vaccinated against influenza, to a balanced diet and appropriate exercise; "6 no": not raw poultry eggs or products, not smuggling and purchase Unknown birds and birds, do not touch or feed migratory birds and birds, do not wild and free to abandon the birds, not to keep birds and other livestock mixed, not to the air is not in circulation or crowded places.

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