Reducing Respiratory Virus Transmission in Bangladeshi Classrooms

This study will test if affordable air cleaning devices (box fans with a filter attached and/or ultraviolet light lamps) installed in classrooms can reduce the number of viral respiratory illnesses schoolchildren experience.

Inclusion Criteria: * Schoolchildren of Bangladesh Government-run primary schools in Dhaka, Bangladesh ages 9 - 12 years, of all gender identifiers (male, female, transgender, prefer not to designate), without specific ethnic selection amongst standard school children of Bangladesh government schools in Dhaka, Bangladesh. Exclusion Criteria: * School children of non-Bangladesh Government-run primary schools and/or schoolchildren who do not attend a Bangladesh Government-run primary school in Dhaka, Bangladesh. * School children who are not able to or have a contraindication with the ability to comply with study procedures.