IWPR estimated the costs and benefits of paid sick days legislation currently under consideration in New York City. The analysis found the legislation would save around

$11m annually due to a reduction in the spread of seasonal flu. That isn’t exactly chickenfeed for most New Yorkers, but the public health benefits associated with paid sick days are likely much higher.

Let’s start with the H1N1 pandemic. According to the CDC, around 61 million Americanswere infected by H1N1 during the last year, and 274,000 individuals had to be hospitalized due to the outbreak. We estimate that during the height of the pandemic in the fall of 2009, 90% of public sector but only 66% of private sector employees stayed at home while infected. Some undoubtedly did not know they were infected, but the difference between the public and private sector figures is consistent with the absence of paid sick days coverage in the private sector.

Without national paid sick days legislation (like the Healthy Families Act) the CDC was reduced to an anemic response: they recommended that employers tell infected employees to stay at “home without fear of losing their jobs.” Even if every employer had followed this advice, the CDC did not suggest that employers pay sick employees who stay home. It is easy to see that this creates situations where some employees would have attended work while infected because they could not afford to lose a day’s pay.

We do not know how many additional cases of H1N1 were directly attributable to the absence of paid sick days legislation. However, given the near-lightning speed of H1N1 transmission last fall, it seems likely that millions if not tens of millions of cases could have – and should have – been avoided.

Next, take the common cold. Research suggest that lost working time for employees who either have colds themselves or stay at home to care for children with colds costs the economy $20b in lost output per year. This estimation demonstrates a shortsighted approach to contagious diseases that also afflicts many employers: they recognize that an ill employee at work is more productive than the same ill employee at home (excepting telecommuters), while ignoring the fact that the productivity of other employees suffers as a disease spreads. That same logic holds for sending ill children to school or child care: the initial parent may be able to get to work on a given day, but other parents will undoubtedly be affected or infected, as will teachers and child care workers, with resulting and avoidable productivity losses.

The list of relevant diseases is, of course, much longer than seasonal flu, pandemics, and the common cold. Among children, diarrhea is highly contagious, as are head lice (ugh!). For all age groups, strep throat, meningitis, and pink eye are contagious.

Further, many foodborne illnesses, such as botulism, are highly contagious.  In addition, ear, nose and throat infections, while not directly contagious, are often set off by the common cold. Ear infections alone are estimated to cause the loss of over $1b in annual parental wages due to absence, and this cost could be reduced if more parents were able to keep children at home when they have a cold.

And now we are seeing an outbreak of whooping cough: 1,500 children in five states have been diagnosed with the disease in recent months, and 6 babies have died. Most cases are due to parents not vaccinating their children – but given that reality, how many of these and future cases could have been prevented if working parents could afford the time to care for ill children?

To reiterate, the $11m benefit figure for paid sick days in New York understates the likely benefits. Whether the true figure is closer to $20m or even $40m, only further research could tell. But all of the monetary cost-benefit analyses completely ignore the human costs of suffering needlessly from contagious diseases.