Nuño M, Chowell G, Gumel A B
Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA.
J R Soc Interface. 2007 Jun 22;4(14):505-21. doi: 10.1098/rsif.2006.0186.
An increasing number of avian flu cases in humans, arising primarily from direct contact with poultry, in several regions of the world have prompted the urgency to develop pandemic preparedness plans worldwide. Leading recommendations in these plans include basic public health control measures for minimizing transmission in hospitals and communities, the use of antiviral drugs and vaccination. This paper presents a mathematical model for the evaluation of the pandemic flu preparedness plans of the United States (US), the United Kingdom (UK) and the Netherlands. The model is used to assess single and combined interventions. Using data from the US, we show that hospital and community transmission control measures alone can be highly effective in reducing the impact of a potential flu pandemic. We further show that while the use of antivirals alone could lead to very significant reductions in the burden of a pandemic, the combination of transmission control measures, antivirals and vaccine gives the most 'optimal' result. However, implementing such an optimal strategy at the onset of a pandemic may not be realistic. Thus, it is important to consider other plausible alternatives. An optimal preparedness plan is largely dependent on the availability of resources; hence, it is country-specific. We show that countries with limited antiviral stockpiles should emphasize their use therapeutically (rather than prophylactically). However, countries with large antiviral stockpiles can achieve greater reductions in disease burden by implementing them both prophylactically and therapeutically. This study promotes alternative strategies that may be feasible and attainable for the US, UK and the Netherlands. It emphasizes the role of hospital and community transmission control measures in addition to the timely administration of antiviral treatment in reducing the burden of a flu pandemic. The latter is consistent with the preparedness plans of the UK and the Netherlands. Our results indicate that for low efficacy and coverage levels of antivirals and vaccine, the use of a vaccine leads to the greatest reduction in morbidity and mortality compared with the singular use of antivirals. However, as these efficacy and coverage levels are increased, the use of antivirals is more effective.
世界上几个地区人类感染禽流感的病例越来越多,主要源于与家禽的直接接触,这促使全球迫切需要制定大流行防范计划。这些计划中的主要建议包括在医院和社区尽量减少传播的基本公共卫生控制措施、使用抗病毒药物和接种疫苗。本文提出了一个数学模型,用于评估美国、英国和荷兰的大流行性流感防范计划。该模型用于评估单一干预措施和联合干预措施。利用来自美国的数据,我们表明,仅医院和社区传播控制措施就能非常有效地降低潜在流感大流行的影响。我们进一步表明,虽然单独使用抗病毒药物可导致大流行负担大幅减轻,但传播控制措施、抗病毒药物和疫苗的联合使用能产生最“理想”的效果。然而,在大流行开始时实施这样的理想策略可能并不现实。因此,考虑其他合理的替代方案很重要。一个理想的防范计划在很大程度上取决于资源的可用性;因此,它是因国家而异的。我们表明,抗病毒药物储备有限的国家应强调将其用于治疗(而非预防)。然而,拥有大量抗病毒药物储备的国家通过预防性和治疗性地使用这些药物,可在更大程度上减轻疾病负担。本研究提出了可能对美国、英国和荷兰可行且可实现的替代策略。它强调了医院和社区传播控制措施的作用,以及及时进行抗病毒治疗在减轻流感大流行负担方面的作用。后者与英国和荷兰的防范计划一致。我们的结果表明,对于抗病毒药物和疫苗的低效力和覆盖率水平,与单独使用抗病毒药物相比,使用疫苗可使发病率和死亡率降低幅度最大。然而,随着这些效力和覆盖率水平的提高,使用抗病毒药物会更有效。