School children get low marks when it comes to spreading germs， often sharing bugs with their classmates. So scientists wondered if putting hand sanitizers into elementary school classrooms would lead to fewer absences.

Researchers in New Zealand set out to discover if using alcohol-based hand sanitizers， in addition to regular hand washing， would cut back on absentee rates in schools.

They recruited 68 primary schools， and all students were given a half-hour hygiene lesson. They then assigned half of the schools to a control group where children washed their hands with soap and water. The schools in the intervention group did the same， but were also asked to use classroom hand sanitizers when they coughed or sneezed， and before meals.

When children missed school， calls were made to find out if the child was sick. The research team checked-in with the caregivers of more than 2，400 children， keeping track of the type and length of their illnesses during 20 weeks of school.

Absentee rates between the two groups were virtually the same， the study authors found.

“These findings suggest that， in high-income countries where clean water for hand washing is readily available， putting resources into extra hand hygiene by providing hand sanitizer in classrooms may not be an effective way to break the child-to-child transmission of infectious diseases，” an accompanying editorial in the journal concluded.