flu

A clinical trial funded by Pfizer has tested a new influenza vaccine based on messenger RNA (mRNA). The phase 3 trial included more than 18,000 people aged 18 to 64, half of whom received the new compound and the other half a conventional vaccine. The results indicate that the mRNA vaccine was more effective, but it also caused more adverse reactions: for example, 5.6% of the volunteers who received it developed a fever, compared to 1.7% of those who received the conventional vaccine. The study is published in the journal NEJM. 

A team led by the CEU San Pablo University has analysed the role of vaccination against influenza on the risk of infection and mortality. The meta-analysis, published in European Respiratory Review, includes 192 articles from different countries over the last 20 years and includes data from more than 6.5 million patients. The results show that the level of protection varies according to age group and influenza subtype. Although it does not reduce the risk of infection for influenza A H3N2 in those over 65 years of age, nor does it show a reduction in mortality for influenza B - which is less associated with mortality than influenza A - overall, vaccination is shown to be effective in both preventing infection and reducing mortality.

Children born in October are more likely to be vaccinated against flu during that month and less likely to be diagnosed with the disease than those born in other months, according to a study published in BMJ. The research involved more than 800,000 US children aged two to five years who were vaccinated against the flu between 1 August and 31 January in the period from 2011 to 2018. The results suggest that the month of birth is related to both the timing of flu vaccination and the likelihood of flu diagnosis, and that October is the best month for flu vaccination.

The European Centre for Disease Prevention and Control (ECDC) reported that on January 29th, Spanish authorities notified a possible case of human infection with swine flu virus A(H1N1)v in a worker from a Catalan pig farm. After being diagnosed with bronchitis, subsequent laboratory analyses confirmed it as swine flu A(H1N1)v. The ECDC informs that the patient has fully recovered, and to date, no new cases have been detected among close contacts or among the worker's colleagues at the farm.

The influenza epidemic could have reached its peak of activity in Primary Care in the last week of 2023, while hospitalization due to influenza continues to rise, according to the latest weekly SiVIRA report published by the Instituto de Salud Carlos III. Thus, during the first week of 2024 there has been a decrease in the primary care rate for influenza: 387 cases per 100,000 inhabitants compared to 430 cases the previous week. This is the first decrease in incidence in four weeks.

Some people may experience long-term symptoms - or 'lingering colds' - after suffering acute respiratory infections that tested negative for covid-19, research concludes. The study, published in the journal EClinicalMedicine, highlights the most common symptoms of these conditions, such as cough, stomach pain and diarrhoea more than four weeks after the initial infection.

A meta-analysis analyzing the results of 18 clinical trials concludes that influenza vaccination may produce more adverse reactions in women than in men. According to the authors, whose research is published in the Journal of Epidemiology & Community Health, "the data suggest that most reactions are mild, self-limited, and rarely serious." "Transparent communication about the increased risk for women could help maintain long-term confidence in health authorities and vaccines," they add.

Influenza A can cause influenza in humans, birds, pigs, and other mammals. In 2009 and 2010, a pandemic caused by the pdm09 strain—popularly called 'swine flu' because it contained genetic sequences from avian, swine, and human influenza—caused thousands of human deaths worldwide. Since then, this lineage has crossed over 370 times from humans to pigs in the United States, according to a study published in PLOS Pathogens. The research also indicates that the circulation of the virus among pigs may cause further evolutionary changes in this lineage, which would increase the risk of the virus passing back to humans.

A study by Spanish researchers coordinated by CEU San Pablo University has analyzed the factors associated with poor prognosis in case of influenza infection. After analyzing data on 48,000 patients from 135 investigations in 28 countries, they conclude that bacterial superinfections increase the risk of death 3.4 times. The authors propose to increase early diagnostic measures so that antibiotics can be administered quickly in cases where there is a higher risk of complications. The results are published in the International Journal of Infectious Diseases.

A study published in the journal Science Translational Medicine shows the results of a phase 1 trial of a new broad-spectrum influenza vaccine. Prepared in the form of nanoparticles containing the H1 hemagglutinin stem-a region that is often conserved in different subtypes of the virus-the vaccine was generally well tolerated by participants, who showed only mild side effects such as tenderness and headaches. The prototype generated an antibody response to group 1 influenza viruses in all age groups.