There are some alternative control strategies based on non-pharmaceutical interventions, including school closures and travel restrictions for mitigating an H1N1 pandemic, which had been adopted by China government to deal with SARS. Figures 4 and 5 give the effectiveness of additional school closures and travel-related intervention strategies, respectively. It is clear that the additional school closures and travel-related interventions could mitigate the influenza pandemic situations. If the additional school closure strategy was only implemented at the beginning stage, that is, stage 1, the total infectious cases would decrease by 19.2%. The strategy at stage 2 also gave a decrease of 47.5% of total cases, which resulted in a decrease of 55.8% at stages 2 and 3.
If the Chinese government adopted the additional school closure strategy during the period of an H1N1 pandemic, the total infectious cases would decrease by 58.7%.
It is clear that the efficiency of this strategy at stage 2 with 80 days closure (from September 1 to November 25, 2009) was highest. From Figure 5, it is clear that stricter travel-related interventions lead to fewer total infectious cases. The additional 50% reduction in trans-city and local travel at stage 2 would result in 50.2% reduction of total cases. The travel-related interventions in the latter stage had almost no effect that could be found from the comparison of various travel-related interventions at stages 1 and 2, with three stages.
A recent study has claimed that travel restrictions have a very low effect on reducing the burden of an epidemic, because after an initial delay of the seeding event, when a local outbreak starts, the importation of infectious cases is negligible with respect to the local exponential growth of the infection.3Here, our results indicated that it would produce a significant compound effect on reducing epidemic burden when the travel-related interventions were implemented together with other mitigation strategies, such as those adopted by China mentioned above. The large-scale school closure and travel restriction strategies would bring much social and economic burden to the government, and also lead to public panic. Therefore, the Chinese government did not adopt these additional strategies considering the mild impact and low fatality rate of an H1N1 pandemic compared with SARS.
in China The large-scale school closure and travel restriction strategies would bring much social and economic burden to the government, and also lead to public panic. Therefore, the Chinese government did not adopt these additional strategies considering the mild impact and low fatality rate of an H1N1 pandemic compared with SARS.
Many research papers on the epidemiology of the pandemic have been published in Western countries but these results are not suitable for application to a large country, such as the People’s Republic of China. In the current modeling field, there are two major classes of methodologies for the simulation of influenza pandemic outbreaks. One is agent-based models and the other is meta-population models.
In China, the initial containment measures that healthy people having close contact with H1N1 patients were quarantined at assembly sites also received crimination. It is true that no country took stricter measures than China to protect residents from H1N1 since the first imported infectious cases on May 11, 2009, considering the experiences of handling SARS. Screening overseas passengers before they disembarked, isolating and treating all cases, and quarantining contacts at assembly sites were the main containment measures until mid-July 2009. Medical institutions for testing patients with influenza-like illness (ILI)
for H1N1 were added to detect and treat infectious cases.
China was one of the earliest countries with vaccination measures against the H1N1 virus. Whether these containment and mitigation strategies that were adopted in China were successful or not should be evaluated for future influenza pandemic considering a huge population, poor health care, and disease surveillance infrastructure in rural areas, and a limited stock of antiviral medicines in China.
Many research papers on the epidemiology of the pandemic have been published in Western countries, but these results are not suitable for application to a large country, such as the People’s Republic of China.
The simulation results showed that these strategies were successful to deal with this influenza pandemic on the whole, although some additional strategies would further reduce the total infectious cases. Contact tracing and CTQ at assembly sites in the early stage, and more medical institutions to detect H1N1 cases and treat serious patients with the increasing cases, effectively delayed the epidemic. The measure of rapid vaccines delivered to students first was evidenced as a correct vaccination strategy in decreasing H1N1 cases.
Closing schools and reducing travel were not undertaken as control strategies in China, but the simulated results indicated that the additional school closure from September 1 to November 25, 2009, would reduce by 47.5% the total infectious cases, and the additional 50% reduction in trans-city and local travel from July 9 to November 25, 2009, also resulted in a 50.2% reduction of cases.