Flu shows more signs of decline in Northern Hemisphere
Flu activity in most of the Northern Hemisphere is declining, with influenza A viruses still predominanting, the World Health Organization (WHO) said today in an update that covers data to Mar 17.
In North America, the H3N2 strain is dominant, with very few influenza B viruses detected, which is unusual for the latter part of the Northern Hemisphere flu season. In Europe, flu is at baseline or low intensity in 34 countries, with activity still reported as medium in 13 countries.
Flu activity in western Asia saw an overall decrease, but levels are still elevated in Kuwait and Saudi Arabia. In East Asia, flu showed signs of decline but is still above seasonal thresholds in China and Hong Kong. Meanwhile, South Korea is experiencing a second wave of flu activity caused by H3N2 and influenza B, following earlier activity from 2009 H1N1. In Southeast Asia, flu activity is still elevated in Thailand, with influenza B most frequently detected.
In the Southern Hemisphere, flu is still at interseasonal levels, except for some parts of Australia that have been experiencing activity over the past several weeks.
Apr 1 WHO global flu update
Flu vaccine tied to lower mortality in heart failure patients
In a study today in Open Forum Infectious Diseases, researchers combed through published data on all-cause mortality rates among heart failure patients who received the influenza vaccine and found that flu vaccination was associated with a 31% decreased risk of all-cause mortality in those patients. The effect was more prominent (51% lower risk) during influenza season.
The authors drew from eight studies published since 2000, which included a total of 82,354 patients (average age of 65) with heart failure. They found that patients who had received seasonal flu vaccine had a reduced risk of all-cause mortality (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.51 to 0.87), especially during flu season (HR, 0.49; 95% CI, 0.30 to 0.69).
"There was no statistically significant difference in the rate of hospitalization among vaccinated and non-vaccinated patients with heart failure (pooled hazard ratio of 0.62 favoring influenza vaccination), which may be due to the relatively limited number of studies," the authors wrote.
Influenza infection has been associated with an increased risk of myocardial infarction and an exacerbation of chronic cardiovascular conditions. Because of this and the evidence gained from this study, the authors recommend seasonal flu vaccines for eligible heart failure patients.
Apr 2 Open Forum Infect Dis study
High-path avian flu outbreaks strike birds in China, Nepal, Taiwan, Mexico
In the latest highly pathogenic avian flu events, China and Nepal reported H5N1 outbreaks in poultry, Taiwan reported more H5N2 on farms, and Mexico reported an H7N3 outbreak in backyard birds, according to World Organization for Animal Health (OIE) reports and other official notifications.
China's H5N1 outbreak occurred at a poultry farm in Xinmin City in Liaoning province, located in the northeast, according to an agriculture ministry statement translated and posted by Avian Flu Diary (AFD), an infectious disease news blog. The event killed 1,000 of 24,500 birds, and the rest were culled to control the spread of the virus. The H5N1 event marks the second recent avian flu outbreak in Liaoning province, which recently reported highly pathogenic H7N9 in peacocks at a zoo in the city of Jinzhou.
In Nepal, the agriculture ministry reported two more H5N1 outbreaks, both at layer farms in Koshi zone in the southeast. The outbreaks, the second and third reported from Nepal since the middle of March, began on Mar 18 and Mar 21, and between the two locations, the virus killed 3,192 of 5,978 birds. The surviving poultry were destroyed.
Taiwan reported more highly pathogenic H5N2 in poultry and in a wild bird, part of activity involving that strain that began in 2015. Of four new poultry outbreaks, all occurred in Taipei City, three involving dead chickens found discarded in nature parks. The fourth outbreak was at a slaughterhouse. Forty-seven of 108 poultry died in the outbreaks.
Health officials have stepped up surveillance of poultry farms in the area. In a separate report, Taiwan also reported an H5N2 detection in a grey heron found dead on Mar 30 in Taipei City.
In Mexico, animal health officials reported a highly pathogenic H7N3 outbreak in backyard birds in Acolman, located in the greater Mexico City area. The event began on Mar 6, killing all 150 birds at the location. The outbreak is now considered resolved. The country's last H7N3 outbreak occurred in April 2018.
Apr 2 AFD post
Mar 31 OIE report on H5N1 in Nepal
Mar 29 OIE report on H5N2 in Taiwanese poultry
Apr 1 OIE report on H5N2 in Taiwanese wild bird
Apr 2 OIE report on H7N3 in Mexico