We’ve written about how smoking is the single largest preventable cause of disease and premature death in the US.  We’ve also highlighted some of the treatments that our 4,000+ members who report tobacco addiction have tried in their quest to quit.

But today, in honor of World No Tobacco Day, we’d like to focus on the global consequences of secondhand smoke, or the smoke that fills restaurants, offices, homes and other enclosed spaces when people burn tobacco products.  Given that there are one billion smokers around the world, secondhand smoke (also known as “passive smoking”) has become a serious public health issue.

How serious?  Deadly serious.  Here are ten hard-hitting facts from the World Health Organization (WHO), the sponsor of World No Tobacco Day.

• There is no safe level of exposure to secondhand tobacco smoke.

• There are more than 4,000 chemicals in tobacco smoke, of which at least 250 are known to be harmful.

• More than 600,000 premature deaths are caused by secondhand smoke each year.

• In 2004, children accounted for 31% of the deaths attributable to secondhand smoke.

• Over 40% of children around the world have at least one parent who smokes.

• Almost half of all children regularly breathe air polluted by tobacco smoke.

• Secondhand smoke can cause sudden death in infants and low birth weight in pregnant women.

• Cigarettes, bidis and water pipes all produce secondhand smoke.

• Less than 11% of the world’s population is protected by comprehensive national smoke-free laws.

• Research shows that smoke-free laws do not harm business – and in fact, are popular.

Want to show your support for World No Tobacco Day?  Join the cause on Facebook.  If you live in the US, you can also check this map to see your state or city’s laws regarding smoking in restaurants, bars and workplaces.

Today, July 28th, marks the first official World Hepatitis Day sponsored by the World Health Organization (WHO) and the World Hepatitis Alliance (WHA). Hepatitis kills more than one million people each year, while millions more suffer acute sickness or long-term ill health. The goal of this new event is to raise awareness of this global health issue while increasing prevention and control efforts.

Specifically, World Hepatitis Day focuses on hepatitis B and hepatitis C, which are both viral infections. Approximately 1 in 12 people worldwide is living with chronic hepatitis B or C, which represents a far greater prevalence than better-known conditions such as HIV or cancer. Yet hepatitis remains poorly known and understood, and the majority of those infected are unaware. Hopefully that can begin to change. With that goal in mind, here are a few quick facts to help raise your knowledge.

Did you know that…

• …there is a vaccine available for hepatitis B that is effective in approximately 95% of cases?
• …both hepatitis B and C can be transmitted through sharing household items such as razors and toothbrushes?
• …these viral infections are considered “silent” because many people experience no symptoms for years?
• …if a hepatitis B infection doesn’t resolve on its own and becomes chronic, it can cause liver cirrhosis or liver cancer? And a liver transplant may be needed?
• …hepatitis B can be spread through unprotected sexual contact, while hepatitis C is contracted through blood-to-blood contact only?

If you didn’t know a few of these facts, learn more about viral hepatitis and how it can be prevented and diagnosed today. You can also learn firsthand from our hepatitis patients here at PatientsLikeMe. As of today, 156 members report hepatitis C while 41 patients report hepatitis B. In both conditions, Prograf, an immunosuppressant drug used to prevent organ rejection following an liver transplant, represents one of the most commonly reported prescription medications while men represent a higher percentage of our membership: 62% for hepatitis C and 63% for hepatitis B. There are also more than 600 discussions of hepatitis across 29 different forum rooms at PatientsLikeMe.

Are you living with chronic hepatitis B or C? Break the silence and share your story in any language on the WHA’s global “Wall of Stories.”