Here's some of HealthDay's top stories for Monday, June 28:

Evidence that Pfizer, Moderna vaccines give long-term immunity. New studies support the notion that mRNA-based vaccines could leave immune system 'memory' cells on guard against COVID for years -- no boosters needed. Read more

Worry over milestones. A new poll finds that a quarter of parents are concerned their child isn't reaching key developmental milestones. But if their sources of info on 'normal' development are wrong, is that worry unfounded? Read more

Anxious owners, anxious dogs? New research -- and the stinging testimony of dog trainers -- suggests that worry-prone humans can transfer that tension to their pet pooches. It doesn't have to be that way. Read more

Heart failure's double whammy. Millions of older Americans struggle with an underperforming heart. Now, new research suggests heart failure may also raise their odds for cancer. Read more

A pacemaker that dissolves when its job is done. When heart patients need an implanted pacemaker to correct a short-term problem, surgery is still needed to remove it. But researchers say they've now created a pacemaker that dissolves away harmlessly after use. Read more

Deadly deductibles. Many Americans are seeing their insurance plan deductibles rising ever higher. Now, research shows that deductibles of $1,000 or more can keep people with sudden chest pain from dialing 911. Read more