Pandemic influenza in Papua New Guinea: a modelling study comparison with pandemic spread in a developed country

Milne, George J; Baskaran, Pravin; Halder, Nilimesh; Karl, Stephan; Kelso, Joel

Using the contact, mobility and transmission features described above, stochastic simulations of influenza spread in Madang were conducted. One new infection per day was introduced into the population during the whole period of the simulations, and randomly allocated to a household. The simulation period was divided into 12 hour day/night periods and during each period a nominal location for each individual was determined. This took into consideration the cycle type (day/night, weekday/weekend), infection state of each individual and whether child supervision was needed to look after a child at home. Individuals occupying the same location during the same time period were assumed to come into potential infective contact. Details of the simulation procedure are presented in [10] . The effectiveness of social distancing interventions, such as school or workplace closure, may be quantified by comparing the passage of the influenza virus in the community with and without interventions activated, and presented as the reduction in the daily and cumulative illness attack rates. Pharmaceutical-based interventions were not considered as antiviral agents may only be available in limited quantities in a PNG setting, whilst a vaccination campaign would face significant delay, supply and delivery constraints. Two intervention strategies considered feasible in a PNG setting were examined. These were: school closure involving all schools, with home isolation of all affected children; and a more rigorous strategy involving school closure coupled with 50% reductions in community-wide contact, workplace participation, and contact in neighbourhood hubs.