Traditionally, in the United States, companies didn't have to offer any paid sick leave (or any paid leave at all, for that matter). Lots of companies do, of course. Professional level employee could pretty much count on at least some paid time off (PTO) either in the form of sick days plus vacation days, or a general pool that they could draw from whether the reason for the day off was the flu or a trip to Disney.

Regardless, 90 percent of us come to work when sick, and that can cause additional problems. Of course, when people are too sick to work, they have to stay home, and companies that don't allow for that are beginning to find out that their lack of sick plans are resulting in a bunch of new laws.

San Francisco was the first to implement mandatory sick time, then Connecticut and New York City. California's legislature just passed a paid sick leave law and Massachusetts just voted one in this week. If your business is in any of these places, you need to know the law for each place. If your business is located elsewhere, pay attention, because it's likely that you're next.

If your company already has a sick leave plan, double check with the lawyers to make sure it meets the law. There may be some surprising things (like who is actually covered in Connecticut). Remember your plan can be more generous than the law, but it can't be less.

I predict that these laws will continue to spread across the nation.

Connecticut: (Currently in effect)

Who's covered: Service workers that work for companies with 50 or more employees. Who is a service worker? It's a bit complicated. A list is available here, starting on page 13. It includes, for instance, registered nurses, waiters, receptionists, and hotel bellhops, but excludes hotel maids and grocery store baggers. Double check the list and when in doubt, classify your borderline employee as eligible. Part time employees are eligible as long as they work 10 hours a week.

How much leave: 1 hour for every 40 worked, up to a maximum of 40 hours a year.

How it can be used: For illness (mental or physical), injury, doctor's appointments including preventative care, to take care of a child or spouse, or for dealing with the aftermath of domestic violence or sexual assault. So, if an employee's child has a check up, that is covered under sick leave.

Official information: Connecticut's sick leave.

San Francisco: (Currently in effect)

Who's covered: All employees

How much leave: 1 hour for ever 30 hours worked, up to 40 hours per year for companies under 11 employees, and up to 72 hours per year for other companies. Unused sick leave rolls over.

How it can be used: Illness, injury, for receiving a diagnosis or to take care of a family member. If the employee has no registered spouse or partner, the employee can designate one person that counts as "family." This person must be identified within 10 days of hire and can be changed once per year.

New York City: (Currently in effect)

Who's covered: All employees, including domestic workers who have worked for more than one year.

How much leave: For companies with 5 or more employees, 40 hours paid leave. For companies with less than 5 employees, 40 hours unpaid leave. Leave is accrued at 1 hour per 30 worked.

How it can be used: Physical or mental health care, or injury for the employee or to care for a family member. It can also be used if the business or your child's school is closed for public health purposes. Family members include domestic partners, step children, siblings, grandparents, grandchildren, etc.

Official Information: New York City Paid Sick Leave

California: (Effective July 2015)

Who's covered: Virtually all employees, with rare exceptions.

How much leave: 24 hour per year, accrued at 1 hour per 30 worked, with a maximum accrual of 48 hours (over multiple years).

How it can be used: Physical or mental health care, including preventative care for the employee and to care for family members. Can also be used by domestic violence and stalking victims.

Massachusetts: (Effective July 2015)

Who's covered: Everyone that works for a company with 11 or more employees earn paid sick time, at smaller companies, employees earn unpaid sick time.

How much leave: 1 hour for ever 30 hours worked, up to 40 hours per year.

How it can be used: For mental or physical illness and follow up care for the employee, spouse or child, including routine care. Domestic violence against the employee or the employee's child is also covered. Employees can require doctor's notes after 24 consecutive work hours ares missed.

Official information: Massachusetts Sick Leave Policy