All articles tagged with #vaccine efficacy
A 40-year-old unvaccinated woman in Jefferson County, Pennsylvania, died from measles complications, marking the third state death this year. Her underlying lung conditions and lack of vaccination made her highly vulnerable. The case highlights the severity of the outbreak and ongoing disputes between state and federal officials over how measles fatalities are counted.
A Lancet review of billions of doses finds mRNA vaccines are safe, highly effective at preventing disease spread, and promising for future uses like cancer treatment; they do not alter human DNA, are safe for children and pregnant people, and boosters extend protection, though rare side effects can occur—emphasizing transparent safety communication to counter misinformation.
The CDC reportedly canceled publication of a planned Morbidity and Mortality Weekly Report article showing the COVID-19 vaccine reduced emergency department visits and hospitalizations by about 50% this past winter, citing methodological concerns raised by acting CDC Director Jay Bhattacharya. The report had cleared peer and internal review before being blocked, amid broader leadership turmoil at the agency and ongoing vaccine-policy debates linked to the administration and its critics. Critics say the move undermines scientific transparency, highlighting tensions between scientific rigor and policy leadership.
Moderna's experimental mRNA flu vaccine showed stronger immune responses than existing vaccines in a late-stage trial, paving the way for approval and the development of a combined COVID and flu vaccine, with plans to resubmit applications later this year amid regulatory discussions.
Moderna's new COVID-19 vaccine, mNEXSPIKE, has received FDA approval for use in adults 65+ and high-risk individuals aged 12-64, showing higher efficacy than its predecessor in clinical trials, with a similar safety profile, and is expected to be available in the US for the 2025-2026 season.
With only 20% of eligible Americans having received the latest COVID-19 vaccine, experts emphasize its importance for protection against severe disease and long COVID. The CDC recommends vaccination for everyone over 6 months old, even if recently infected, as immunity wanes over time. The mRNA vaccines from Pfizer and Moderna, and the protein-based Novavax, are all effective options. Timing is crucial for optimal protection, especially before winter travel and gatherings. Global disparities in vaccine access remain, with lower uptake in low- and middle-income countries.
The FDA is planning for an updated Covid vaccine to be rolled out this winter, with officials expecting to offer the shots annually, similar to the flu vaccine. The agency anticipates changes to the vaccine composition may be necessary based on the currently circulating strains of the virus, and the vaccine may need to be overhauled every year to provide protection against emerging variants. The FDA's Vaccines and Related Biological Products Advisory Committee will hold a meeting in May to discuss the updates, and vaccine companies like Pfizer and Moderna will be asked to update their shots accordingly.
New research suggests that alternating arms for multi-dose vaccinations, such as the COVID-19 vaccine, can lead to a significant increase in immune response, up to four times, challenging previous assumptions. The study, involving 947 participants and published in The Journal of Clinical Investigation, found that receiving shots in both arms resulted in a heightened immune response to both the original SARS-CoV-2 strain and the omicron variant. While further research is needed, the findings could have implications for enhancing vaccine efficacy against variants and may apply to other multi-dose vaccinations.
Israel has reported approximately 200 cases of a new COVID-19 sub-variant named JN.1, which is contributing to a slight increase in morbidity rates. The CDC has warned of its rapid spread and potential impact on hospitalizations, although early data indicates current vaccines may be less effective against it. The WHO expert group believes the changes in JN.1 do not necessitate a new vaccine formula at this time.
Research suggests that various lifestyle factors, such as mood, sleep, diet, exercise, and social interactions, can affect the efficacy of vaccines, including flu shots and COVID-19 jabs. Positive mood, adequate sleep, a healthy diet, regular exercise, and strong social connections have been associated with better antibody response to vaccines. Factors like age and genetics also play a role in vaccine response. While the exact mechanisms are not fully understood, these lifestyle factors can potentially enhance the immune system's ability to fight diseases and improve vaccine efficacy.
The reason some people feel sick after receiving the flu shot or a COVID booster is likely due to the immune response triggered by the vaccine. Vaccines simulate an infection, causing the immune system to respond and produce antibodies to fight off the simulated infection. Feeling unwell after vaccination is a sign that the immune system is working to prevent severe illness. Common side effects include soreness, redness, swelling at the injection site, as well as flu-like symptoms such as headache, fever, muscle aches, fatigue, and nausea. These symptoms typically last for a few days. Lack of symptoms does not mean the vaccine is not working, as research has shown that individuals with more symptoms tend to have a stronger antibody response. It is important to seek medical attention if symptoms persist for longer than a day or if there are signs of a true infection.
A meta-analysis of 24 studies estimates that three doses of COVID-19 vaccine offer 69% efficacy against long COVID, while two doses provide 37% efficacy. The prevalence of long COVID was significantly lower among vaccinated individuals compared to unvaccinated individuals. The most commonly reported symptoms of long COVID were fatigue, muscle weakness, muscle pain, anxiety, memory problems, sleep problems, and shortness of breath. The study authors recommend standardized definitions of long COVID and further research on vaccine effectiveness against persistent symptoms, bivalent vaccines, booster doses, and mixed-vaccine strategies.
The Africa CDC has issued a statement on the new COVID-19 strain, EG.5, which has been designated as a variant of interest by the WHO. Over 13,000 sequences of EG.5 have been reported in 59 countries across five regions. While there has been an increase in hospitalizations in certain countries, there is currently no evidence of an association between EG.5 and severity or hospitalization of COVID-19 cases. The Africa CDC recommends accelerating the immunization of high-risk populations, strengthening surveillance systems, reinforcing genomic surveillance, conducting epidemiological investigations, and sharing data on emerging variants. The Africa CDC will continue to monitor the situation and provide further guidance as more information becomes available.
The World Health Organization is monitoring the XBB.1.16 subvariant of COVID-19 due to potential changes in its transmissibility, severity, immunity-evading abilities, and vaccine and treatment efficacy. The subvariant has one extra spike protein mutation than previous subvariants, which may influence its illness severity. While most patients are experiencing only mild symptoms, health officials remain watchful as heightened transmissibility and illness severity are not out of the question.