ASSESSMENT OF TRANSMISSION AND RELATED FACTORS IN ASYMPTOMATIC COVID-19 CASES
Year 2022,
Volume: 7 Issue: 1, 162 - 176, 31.01.2022
Şükran Peker
,
Merve Kurnaz Ay
,
Şevket Girgin
,
Ahmet Topuzoğlu
,
Dilşad Save
Abstract
COVID-19 (SARS CoV-2) pandemic is among the most important public health issues today, due to its prevalence and being an easily transmitted infection. The clinical picture of the infection can vary from asymptomatic to multiorgan dysfunction. The rate of cases with asymptomatic COVID-19 infection ranges in the literature in a spectrum of 17.9% to higher than 80.0%. An asymptomatic case can infect COVID-19 to large masses if precautions are not taken. In addition, there are uncertainties regarding the viral load, viral transmission patterns, and potential infectivity of patients in asymptomatic cases. Serological tests can monitor the effects of the disease on the immune system, but there is no clear consensus on the duration of immunity in individuals who have had the infection. Clarifying these uncertainties has an important place in the combat against the epidemic. In this article; studies on cases with asymptomatic COVID-19 infection were compiled, and issues related to the detection of the cases, their transmission levels, viral loads, and duration of transmission were discussed.
References
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- 33. Samaddar A, Gadepalli R, Nag VL, Misra S, Bhardwaj P, Singh P, et al., editors. Viral Ribonucleic Acid Shedding and Transmission Potential of Asymptomatic and Paucisymptomatic Coronavirus Disease 2019 Patients. Open Forum Infect Dis. 2021.
- 34. Piguillem F, Shi L. Optimal COVID-19 quarantine and testing policies. 2020.
- 35. Khairulbahri M. Modeling the COVID-19 transmission in Italy: The roles of asymptomatic cases, social distancing, and lockdowns. MedRxiv. 2021.
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ASEMPTOMATİK COVID-19 OLGULARINDA BULAŞTIRICILIĞIN VE İLİŞKİLİ FAKTÖRLERİN DEĞERLENDİRİLMESİ
Year 2022,
Volume: 7 Issue: 1, 162 - 176, 31.01.2022
Şükran Peker
,
Merve Kurnaz Ay
,
Şevket Girgin
,
Ahmet Topuzoğlu
,
Dilşad Save
Abstract
COVID-19 (SARS-CoV-2) pandemisi; prevalansı, ciddi klinik sonuçları ve kolay bulaşan bir enfeksiyon olması nedeniyle günümüzün en öncelikli halk sağlığı sorunları arasında bulunmaktadır. Enfeksiyonun kliniği asemptomatik düzeyden çoklu organ yetmezliğine değişiklik göstermektedir. Araştırmalara göre COVID-19 enfeksiyonu geçirenlerin %17,9-%80,0’inin asemptomatik olgular olduğu bildirilmiştir. Asemptomatik olguların önlem alınmaması halinde COVID-19’u geniş kitlelere bulaştırma potansiyeli üzerine tartışmalar sürmektedir. Ayrıca asemptomatik olgularda hastaların viral yükü, viral bulaşma modelleri ve potansiyel enfektivitesi ile ilgili belirsizlikler mevcuttur. Serolojik testlerle hastalığın immün sistem üzerindeki etkileri izlenebilmektedir fakat enfeksiyonu geçiren bireylerde bağışıklık süresine ilişkin net bir uzlaşma sağlanamamıştır. Bu belirsizliklerin açığa kavuşturulması salgınla mücadele açısından önemli bir yere sahiptir.
Bu makalede; COVID-19 enfeksiyonunu asemptomatik olarak geçiren olgularla ilgili yapılmış olan araştırmalar
derlenerek olguların tespiti, hastalığı bulaştırma düzeyleri, viral yükleri, bulaştırıcılık süreleri ve potansiyel enfektiviteleri
ile ilgili konular tartışılmıştır.
References
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- 26. Mizumoto K, Kagaya K, Zarebski A, Chowell G. Estimating the asymptomatic proportion of coronavirus disease 2019 (COVID-19) cases on board the Diamond Princess cruise ship, Yokohama, Japan, 2020. Eurosurveillance. 2020;25(10):2000180.
- 27. Temkin E, Schwaber MJ, Solter E, Vaturi A, Hen D, Lugassy CG, et al. Extremely low prevalence of asymptomatic COVID-19 among healthcare workers caring for COVID-19 patients in Israeli hospitals: a cross-sectional study. CMI. 2021;27(1):130. e1-e4.
- 28. Hu Z, Song C, Xu C, Jin G, Chen Y, Xu X, et al. Clinical characteristics of 24 asymptomatic infections with COVID-19 screened among close contacts in Nanjing, China. Sci China Life Sci. 2020;63(5):706-11.
- 29. Zou L, Ruan F, Huang M, Liang L, Huang H, Hong Z, et al. SARS-CoV-2 viral load in upper respiratory specimens of infected patients. NEJM. 2020;382(12):1177-9.
- 30. Arons MM, Hatfield KM, Reddy SC, Kimball A, James A, Jacobs JR, et al. Presymptomatic SARS-CoV-2 infections and transmission in a skilled nursing facility. NEJM. 2020;382(22):2081-90.
- 31. Liu Z, Chu R, Gong L, Su B, Wu J. The assessment of transmission efficiency and latent infection period in asymptomatic carriers of SARS-CoV-2 infection. Int J Infect Dis. 2020;99:325-7.
- 32. Tan F, Wang K, Luo J, Liu J, Liu D, Zhou R. Viral transmission and clinical features in asymptomatic carriers of SARS-CoV-2 in Wuhan, China. Front Med. 2020;7:547.
- 33. Samaddar A, Gadepalli R, Nag VL, Misra S, Bhardwaj P, Singh P, et al., editors. Viral Ribonucleic Acid Shedding and Transmission Potential of Asymptomatic and Paucisymptomatic Coronavirus Disease 2019 Patients. Open Forum Infect Dis. 2021.
- 34. Piguillem F, Shi L. Optimal COVID-19 quarantine and testing policies. 2020.
- 35. Khairulbahri M. Modeling the COVID-19 transmission in Italy: The roles of asymptomatic cases, social distancing, and lockdowns. MedRxiv. 2021.
- 36. He X, Lau EH, Wu P, Deng X, Wang J, Hao X, et al. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nat Med. 2020;26(5):672-5.
- 37. Xu D, Zhang Z, Jin L, Chu F, Mao Y, Wang H, et al. Persistent shedding of viable SARS-CoV in urine and stool of SARS patients during the convalescent phase. Eur J Clin Microbiol Infect Dis. 2005;24(3):165-71.
- 38. Wölfel R, Corman V, Guggemos W, Seilmaier M, Zange S, Müller M, et al. 336 Rothe C, Hoelscher M, Bleicker T, Brünink S, Schneider J, Ehmann R, Zwirglmaier K, Drosten C, Wendtner 337 C. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020;581(7809):465-9.
- 39. Wu J, Mafham M, Mamas M, Rashid M, Kontopantelis E, Deanfield J, et al. Place and underlying cause of death during the COVID19 pandemic: retrospective cohort study of 3.5 million deaths in England and Wales, 2014 to 2020. MedRxiv. 2020.
- 40. Lan L, Xu D, Ye G, Xia C, Wang S, Li Y, et al. Positive RT-PCR test results in patients recovered from COVID-19. JAMA. 2020;323(15):1502-3.
- 41. Byrne AW, McEvoy D, Collins AB, Hunt K, Casey M, Barber A, et al. Inferred duration of infectious period of SARS-CoV-2: rapid scoping review and analysis of available evidence for asymptomatic and symptomatic COVID-19 cases. BMJ Open. 2020;10(8):e039856.
- 42. Weitz JS, Beckett SJ, Coenen AR, Demory D, Dominguez-Mirazo M, Dushoff J, et al. Modeling shield immunity to reduce COVID-19 epidemic spread. Natur Med. 2020:1-6.
- 43. Phelan AL. COVID-19 immunity passports and vaccination certificates: scientific, equitable, and legal challenges. Lancet. 2020;395(10237):1595-8.
- 44. Cao W-C, Liu W, Zhang P-H, Zhang F, Richardus JH. Disappearance of antibodies to SARS-associated coronavirus after recovery. NEJM. 2007;357(11):1162-3.
- 45. Choe PG, Perera R, Park WB, Song K-H, Bang JH, Kim ES, et al. MERS-CoV antibody responses 1 year after symptom onset, South Korea, 2015. Emerg Infect Dis. 2017;23(7):1079.
- 46. Guo X, Guo Z, Duan C, Wang G, Lu Y, Li M, et al. Long-term persistence of IgG antibodies in SARS-CoV infected healthcare workers. MedRxiv. 2020.
- 47. Payne DC, Iblan I, Rha B, Alqasrawi S, Haddadin A, Al Nsour M, et al. Persistence of antibodies against Middle East respiratory syndrome coronavirus. Emerg Infect Dis. 2016;22(10):1824.
- 48. Wu F, Wang A, Liu M, Wang Q, Chen J, Xia S, et al. Neutralizing antibody responses to SARS-CoV-2 in a COVID-19 recovered patient cohort and their implications. MedRxiv. 2020.
- 49. Wang X, Guo X, Xin Q, Pan Y, Hu Y, Li J, et al. Neutralizing antibodies responses to SARS-CoV-2 in COVID-19 inpatients and convalescent patients. Clin Infect Dis. 2020.
- 50. Kissler SM, Tedijanto C, Goldstein E, Grad YH, Lipsitch M. Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period. Science. 2020;368(6493):860-8.