Booth George, Hadjichrysanthou Christoforos, Rice Keira L, Frallicciardi Jacopo, Magyarics Zoltán, de Wolf Frank, Goudsmit Jaap, Beukenhorst Anna L, Anderson Roy
Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK; Leyden Laboratories BV, Leiden, The Netherlands.
Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK; Department of Mathematics, University of Sussex, Brighton, UK.
J Theor Biol. 2025 Dec 7;615:112237. doi: 10.1016/j.jtbi.2025.112237. Epub 2025 Aug 10.
Superspreading events are known to disproportionally contribute to onwards transmission of epidemic and pandemic viruses. Preventing infections in a small number of high-transmission settings is therefore an attractive public health goal.
We use deterministic and stochastic mathematical modelling to quantify the impact of intranasal sprays in containing outbreaks at a confirmed superspreading event (the 2020 SARS-CoV-2 outbreak at the Diamond Princess cruise ship) and a conference event that led to extensive transmission.
In the Diamond Princess cruise ship case study, there exists a 7-14-day window of opportunity for widespread prophylactic intranasal spray usage to significantly impact the number of infections averted. Given an immediate response to a known SARS-CoV-2 outbreak, alongside testing and social distancing measures, prophylactic efficacy and coverage greater than 65% could reduce the average number of infections by over 90%. In the conference case study, in the absence of additional public health interventions, analyses suggest much higher prophylactic efficacy and coverage is required to achieve a similar outcome on a population level. However, prophylactic use can halve an individual's probability of being infected, and significantly reduce the probability of developing a severe infection.
At a known potential superspreading event, early use of intranasal sprays can complement quarantining measures and significantly suppress a SARS-CoV-2 outbreak, even at suboptimal coverage. At a potential superspreading event of short duration, intranasal sprays can reduce individuals' risk of infection, but in the absence of other interventions, they cannot prevent all infections or all onwards community transmission.
Where crowds are in close contact in closed spaces, respiratory viruses like coronavirus spread easily. At such events, superspreading may occur: one person transmitting the virus to many other event-goers, fuelling the epidemic or pandemic. We used mathematical modelling to predict whether antiviral nose sprays which act immediately can prevent such superspreading events. We found that early use of nose sprays can suppress a SARS-CoV-2 outbreak, even if not everybody is treated with the nose spray, as long as people are also tested and use social distancing if infected. At a conference where people do not quarantine, it is more difficult to prevent spreading of the virus altogether with nose sprays alone. However, at an individual level, people who take the nose spray have lower chance of getting infected with the virus.
已知超级传播事件对流行病和大流行病毒的进一步传播贡献不成比例。因此，在少数高传播环境中预防感染是一个有吸引力的公共卫生目标。
我们使用确定性和随机性数学模型来量化鼻喷雾剂在控制已确认的超级传播事件（2020年钻石公主号游轮上的新冠病毒疫情）和导致广泛传播的会议活动中的疫情爆发的影响。
在钻石公主号游轮案例研究中，存在一个7至14天的机会窗口，在此期间广泛预防性使用鼻喷雾剂会对避免感染的数量产生重大影响。如果对已知的新冠病毒疫情立即做出反应，同时采取检测和社交距离措施，预防效果和覆盖率超过65%可将平均感染人数减少90%以上。在会议案例研究中，在没有额外公共卫生干预措施的情况下，分析表明需要更高的预防效果和覆盖率才能在人群层面实现类似结果。然而，预防性使用可将个人感染概率减半，并显著降低发生严重感染的概率。
在已知的潜在超级传播事件中，早期使用鼻喷雾剂可补充隔离措施，并显著抑制新冠病毒疫情爆发，即使覆盖率未达到最佳水平。在持续时间较短的潜在超级传播事件中，鼻喷雾剂可降低个人感染风险，但在没有其他干预措施的情况下，它们无法预防所有感染或所有后续社区传播。
在封闭空间中人群密切接触的地方，像冠状病毒这样的呼吸道病毒很容易传播。在这类活动中，可能会发生超级传播：一个人将病毒传播给许多其他活动参与者，助长疫情或大流行。我们使用数学模型来预测能立即起作用的抗病毒鼻喷雾剂是否可以预防此类超级传播事件。我们发现，早期使用鼻喷雾剂可以抑制新冠病毒疫情爆发，即使并非每个人都使用鼻喷雾剂，只要人们也接受检测并且在感染时保持社交距离。在一个人们不进行隔离的会议上，仅靠鼻喷雾剂完全预防病毒传播更加困难。然而，在个人层面，使用鼻喷雾剂的人感染病毒的几率较低。
