|Year : 2020 | Volume
| Issue : 6 | Page : 139-141
Significance of super spreader events in COVID-19
Sanjiv Kumar1, Shreya Jha2, Sanjay Kumar Rai3
1 Chair, Indian Public Health Academy, All India Institute of Medical Sciences, New Delhi, India
2 Consultant, Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India
3 Professor, Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India
|Date of Submission||04-May-2020|
|Date of Decision||05-May-2020|
|Date of Acceptance||11-May-2020|
|Date of Web Publication||2-Jun-2020|
Room No. 26, Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi
Source of Support: None, Conflict of Interest: None
| Abstract|| |
The number of secondary cases from each primary case determines how fast an epidemic grows. It is known that all cases do not spread the infection equally; super spreaders play an important role as they contribute disproportionately to a much larger number of cases including in the ongoing COVID-19 pandemic. Super spreaders have been reported for more than a century, but limited information is available in scientific literature. An epidemic containment strategy needs to include early identification of super spreaders to limit an explosive growth. Super spreaders tend to get stigmatized, resulting in late reporting and hiding of cases. It is important for program managers to be sensitive to the manner in which related information is shared with media and general public.
Keywords: COVID-19, infection, super spreader
|How to cite this article:|
Kumar S, Jha S, Rai SK. Significance of super spreader events in COVID-19. Indian J Public Health 2020;64, Suppl S2:139-41
|How to cite this URL:|
Kumar S, Jha S, Rai SK. Significance of super spreader events in COVID-19. Indian J Public Health [serial online] 2020 [cited 2020 Aug 11];64, Suppl S2:139-41. Available from: http://www.ijph.in/text.asp?2020/64/6/139/285614
| Introduction|| |
COVID-19 is a highly contagious disease and spreads rapidly overwhelming the best health systems in the world and devastating the best performing economies. Super spreader events (SSEs) play an important role in accelerating the spread of the epidemic. A better understanding of SSE will help improve evidence-based control measures and deal with anticipated waves of the current pandemic and future epidemics. The super spreaders have been reported in literature for over a century, the first one being Typhoid Mary. The city of Zamora, Spain, had a religious event of nine days to honor Saint Rocco (Saint of Plague) during Spanish flu. The city reported a large number of deaths and one of the highest case fatality rates. SSEs have been reported for many infectious disease outbreaks such as measles, tuberculosis, Ebola, and severe acute respiratory syndrome. There is a lack of consistent and generally accepted definitions. The criteria of SSEs and their impact on outbreak control measures are still unclear. This paper reviews the role of SSE in spreading COVID 19 with examples from across the world.
| Role of Super Spreader Events in Spreading Infection|| |
In any population, there can be a small proportion of individuals who mix freely with others while the efforts are made to isolate them. A bartender super spreader in a skiing resort in Austria infected more than a thousand persons that eventually spread to at least five countries across Europe. [Table 1] shows some examples of COVID-19 SSE to illustrate the importance of super spreaders.
It is important to note that religious teachers and religious gathering contributed a lot to SSEs across the world. The religious gatherings must also be stopped when academic institutions are closed. Mobilizing religious leaders should be included as a priority in an epidemic containment plan from early stages.
| Characteristics of Super Spreaders|| |
Most of the SSEs are identified in hindsight as it is not possible to know in advance. Some characteristics of super spreaders include the following.
- Heavy dose of infection and shed more virus
- May have more severe cough, thereby more likely to spread infection
- In most instances, have spread infection before they even know that they are infected.
- Work in or visit crowded places often
- Travel to many places because of nature of work such as religious leaders, restaurant, hotel, or hospital staff
- Work or live in a confined space which increases the possibility of transmission
- Risk takers may willfully disregard instructions to quarantine or intention to harm others
- Public gathering, often religious gatherings.
A super spreader may have more than one of the above characteristics.
| Integrating Super Spreaders Identification and Control|| |
It is important to study super spreaders and prepare to deal with these as an integral part of an epidemic control and management strategy. Identification of potential super spreader in media is likely to create strong stigma attached to not only individuals and communities involved against those from disease but also their families, neighbors, and health-care providers. Typhoid Mary spent rest of her remaining life, about 30 years, in hospital in isolation after detection. Some examples from the ongoing phase in India include a hearing and speech impaired suspected case abandoned by family in AIIMS Raipur who tested negative; a 35-year-old suspect case in Kerala suspected found dead but later tested negative; and a 36-year-old woman in Agra was shot dead when her family reported a visitor in neighborhood.
It is important that both health authorities and media are sensitive about details of super spreaders and SSE; else, it will not only push the super spreaders but also other cases and contacts into hiding limiting the containment efforts. A study on SSE in Middle East respiratory syndrome (MERS) in Korea concluded that understanding of SSE is tremendously important to make prediction models and plan prevention and control strategies. We can gain a better understanding of heterogeneity parameters and their associated factors by analyzing and modeling the epidemic data of the MERS outbreak in Korea.
The Pareto Principe in spread of infection, i.e., 20% of cases responsible for 80% of spread, has been applied to other infectious diseases. Super spreaders are certainly among these 20%. Heterogeneity in transmission is a challenge for infectious disease dynamics and control. An 80–20 “Pareto” rule may be applicable to spread of infection in COVID 19 pandemic as well, and requires validation.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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