PMC:2854337 / 15748-21046 JSONTXT

{"target":"http://pubannotation.org/docs/sourcedb/PMC/sourceid/2854337","sourcedb":"PMC","sourceid":"2854337","source_url":"https://www.ncbi.nlm.nih.gov/pmc/2854337","text":"Control strategies\nThis article explored four kinds of interventions with the aim of analyzing their effectiveness in terms of suppressing an influenza epidemic: administration of antiviral drugs for prophylaxis through two methods of medication, TAP and STAP; school closure; restraint; combinations of these interventions were also analyzed. It was assumed that all interventions would be started 14 days after the introduction of the initial patient.\n\nTargeted antiviral prophylaxis\nIn the TAP intervention strategy, patients with symptoms as well as persons in close contact with them are treated with antiviral drugs in accordance with the “Pandemic Influenza Preparedness Action Plan” [5]. TAP is regarded as an important intervention in the early phase of an influenza epidemic in the “Guidelines for the Prevention and Control of Pandemic Influenza” [25]. In this model, it was assumed that a patient with symptoms would be treated with an antiviral drug just being diagnosed with a novel influenza infection, that all members of his/her household would be dosed with an antiviral drug for prophylaxis on that same day of diagnosis or thereafter, and that a person belonging to the same social activity group as the diagnosed patient would be traced, if possible, and treated with an antiviral drug within a few days of contact [12]. In this strategy, no members of the casual contact group could be traced. One of the advantages of TAP intervention is the small amount of antiviral drugs that are distributed for prophylaxis.\nThe model limits the possible number of symptomatic cases for whom members of the social activity group can be traced for close contact to ten persons for each ward per day because of the limited capacity of the healthcare center (only one center for each ward in Sapporo city) [32]. During the swine flu A (H1N1) outbreak in Japan, not all of the persons in close contact with an infected person could be traced and, moreover, some traced persons refused to take antiviral drugs [36]. Various situations with respect to the proportion of identifiable close contact persons (30, 50, and 70%) and necessary tracing periods (2, 4, and 6 days) were examined.\n\nSchool-age TAP\nIn the STAP intervention strategy, antiviral drugs are distributed to the children of a school once a child is diagnosed with a novel influenza at a medical institution to prevent infection among school-aged children, who have a high attack rate. Naturally, all household members of the infected person would be dosed with an antiviral drug for prophylaxis from the day of diagnosis. Proportions for the coverage of distribution to children in the affected schools of 30, 50, and 70% were investigated, as was the necessary tracing period of 2, 4, and 6 days.\n\nSchool closure\nSchool closure is regarded as an important intervention measure because an influenza epidemic can be spread widely among children at school [5]. In this model, when a person is diagnosed with a novel influenza at a medical institution in a ward, school closure will be implemented from the day following the diagnosis for all schools in this ward. The “Guidelines for the Prevention and Control of Pandemic Influenza” [25] states that a judgment based on the epidemiological investigation will end the period of school closure; however, in our model, school closure was assumed to be continued until no patients were detected in the ward.\n\nRestraint\nRequests to residents to refrain from going out unnecessarily have been noted as a containment policy [5]. Restraint was generally recognized as a preventive measure by residents in Hong Kong when they experienced an outbreak of severe acute respiratory syndrome (SARS) [34]. However, many people in Japan are unwilling to practice a voluntary policy of restraint, and in one study, only 46.2% of people expressed willingness to practice restraint in a “Survey of pandemic behavior: to stay at home or not.” [37]. When a person is diagnosed with a novel influenza at a medical institution in a ward, restraint will be performed in this ward from the day following diagnosis. Various rates of restraint (10, 30, and 50%) were investigated. The period of restraint was assumed to continue for 2 weeks, and a person who agreed to restraint once was not required to be restrained again for at least 1 month.\n\nCombined intervention\nWe investigated five scenarios with different combinations of interventions for their effects on suppression; these included the administration of antiviral drugs for treatment (TAP/STAP) with/without school closure and with/without restraint (Table 3). In TAP and STAP, the necessary tracing period and the coverage were set to 4 days and 50%, respectively; for restraint, the rate was set to 30%. TAP should be terminated when the number of patients reaches ten persons for each ward per day because the “Pandemic Influenza Preparedness Action Plan” [5] showed that the administration of medicine to persons in close contact with a patient should be stopped after an influenza infection has spread widely.\nTable 3 Scenarios with different combinations of intervention measures\nScenario TAP STAP School closure Restraint\n1 ○ ○\n2 ○ ○\n3 ○ ○\n4 ○ ○ ○\n5 ○ ○ ○\nTAP targeted antiviral prophylaxis, STAP school-age targeted antiviral prophylaxis","divisions":[{"label":"title","span":{"begin":0,"end":18}},{"label":"p","span":{"begin":19,"end":453}},{"label":"sec","span":{"begin":455,"end":2190}},{"label":"title","span":{"begin":455,"end":485}},{"label":"p","span":{"begin":486,"end":1534}},{"label":"p","span":{"begin":1535,"end":2190}},{"label":"sec","span":{"begin":2192,"end":2766}},{"label":"title","span":{"begin":2192,"end":2206}},{"label":"p","span":{"begin":2207,"end":2766}},{"label":"sec","span":{"begin":2768,"end":3421}},{"label":"title","span":{"begin":2768,"end":2782}},{"label":"p","span":{"begin":2783,"end":3421}},{"label":"sec","span":{"begin":3423,"end":4336}},{"label":"title","span":{"begin":3423,"end":3432}},{"label":"p","span":{"begin":3433,"end":4336}},{"label":"title","span":{"begin":4338,"end":4359}},{"label":"label","span":{"begin":5068,"end":5075}},{"label":"caption","span":{"begin":5076,"end":5138}},{"label":"p","span":{"begin":5076,"end":5138}},{"label":"table","span":{"begin":5139,"end":5215}},{"label":"tr","span":{"begin":5139,"end":5181}},{"label":"th","span":{"begin":5139,"end":5147}},{"label":"th","span":{"begin":5148,"end":5151}},{"label":"th","span":{"begin":5152,"end":5156}},{"label":"th","span":{"begin":5157,"end":5171}},{"label":"th","span":{"begin":5172,"end":5181}},{"label":"tr","span":{"begin":5182,"end":5187}},{"label":"td","span":{"begin":5182,"end":5183}},{"label":"td","span":{"begin":5184,"end":5185}},{"label":"td","span":{"begin":5186,"end":5187}},{"label":"tr","span":{"begin":5188,"end":5193}},{"label":"td","span":{"begin":5188,"end":5189}},{"label":"td","span":{"begin":5190,"end":5191}},{"label":"td","span":{"begin":5192,"end":5193}},{"label":"tr","span":{"begin":5194,"end":5199}},{"label":"td","span":{"begin":5194,"end":5195}},{"label":"td","span":{"begin":5196,"end":5197}},{"label":"td","span":{"begin":5198,"end":5199}},{"label":"tr","span":{"begin":5200,"end":5207}},{"label":"td","span":{"begin":5200,"end":5201}},{"label":"td","span":{"begin":5202,"end":5203}},{"label":"td","span":{"begin":5204,"end":5205}},{"label":"td","span":{"begin":5206,"end":5207}},{"label":"tr","span":{"begin":5208,"end":5215}},{"label":"td","span":{"begin":5208,"end":5209}},{"label":"td","span":{"begin":5210,"end":5211}},{"label":"td","span":{"begin":5212,"end":5213}},{"label":"td","span":{"begin":5214,"end":5215}}],"tracks":[{"project":"MyTest","denotations":[{"id":"19941171-16585506-28350082","span":{"begin":1337,"end":1339},"obj":"16585506"}],"namespaces":[{"prefix":"_base","uri":"https://www.uniprot.org/uniprot/testbase"},{"prefix":"UniProtKB","uri":"https://www.uniprot.org/uniprot/"},{"prefix":"uniprot","uri":"https://www.uniprot.org/uniprotkb/"}],"attributes":[{"subj":"19941171-16585506-28350082","pred":"source","obj":"MyTest"}]},{"project":"2_test","denotations":[{"id":"19941171-16585506-28350082","span":{"begin":1337,"end":1339},"obj":"16585506"}],"attributes":[{"subj":"19941171-16585506-28350082","pred":"source","obj":"2_test"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"MyTest","color":"#e1ec93","default":true},{"id":"2_test","color":"#dd93ec"}]}]}}