Epidemiology of COVID-19

Cover Page


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription or Fee Access

Abstract

The review examines and discusses the spread of COVID-19, current sources of the pathogen, mechanisms and ways of transmission of SARS-CoV-2. It is shown that the leading sources of infection in the ongoing COVID-19 pandemic are patients with manifest forms of the disease on the 1st-2nd day of the disease. A week after the appearance of the first symptoms of the disease, the epidemiological significance of patients as sources of infection decreases sharply. And unlike many other respiratory infections, patients with subclinical forms of the disease who remain highly active are less dangerous epidemiologically.

Despite the fact that the causative agents of severe acute respiratory syndrome have penetrated into the human population from small vertebrates, the epidemiological significance of the latter in the ongoing COVID-19 pandemic is negligible. The actual mechanism of transmission of SARS-CoV-2 is aspiration. The other mechanisms of pathogen transmission (fecal-oral, transmissible, contact, vertical), previously discussed as competing with aspiration, have no epidemiological significance. The main transmission path of SARS-CoV-2 is airborne. The contact-household transmission path is much less relevant, and other ways are not proven. Leading in the spread of the virus in the human population is a relatively close (up to 2 meters), long-term, not protected by personal protective equipment, contact of the patient with a healthy one. There is no epidemiological significance of long-distance transmission of the virus.

Full Text

Restricted Access

About the authors

Murad Z. Shakhmardanov

The Russian National Research Medical University named after N.I. Pirogov

Email: mur2025@rambler.ru
ORCID iD: 0000-0002-3168-2169
SPIN-code: 3312-4052

MD, Dr. Sci. (Med), Professor

Russian Federation, Moscow

Vladimir V. Nikiforov

The Russian National Research Medical University named after N.I. Pirogov

Email: v.v.nikiforov@gmail.com
ORCID iD: 0000-0002-2205-9674
SPIN-code: 9044-5289

MD, Dr. Sci. (Med), Professor

Russian Federation, Moscow

Anna A. Skryabina

The Russian National Research Medical University named after N.I. Pirogov

Email: anna.skryabina.85@mail.ru
ORCID iD: 0000-0002-2098-222X
SPIN-code: 3692-6818
Russian Federation, Moscow

Yuri N. Tomilin

The Russian National Research Medical University named after N.I. Pirogov

Email: papa220471@mail.ru
ORCID iD: 0000-0003-2767-4868
SPIN-code: 8938-2621

MD, Cand. Sci. (Med.)

Russian Federation, Moscow

Aida S. Abusueva

Dagestan State Medical Academy

Email: amur39@mail.ru
ORCID iD: 0000-0002-6999-1696
SPIN-code: 4713-7110

MD, Cand. Sci. (Med.), Associate Professor

Russian Federation, Makhachkala

Svetlana V. Burova

The Russian National Research Medical University named after N.I. Pirogov

Author for correspondence.
Email: svburova@list.ru
ORCID iD: 0000-0001-7664-7685
SPIN-code: 9165-2625

MD, Cand. Sci. (Med.), Associate Professor

Russian Federation, Moscow

References

  1. Havers FP, Reed C, Lim T, et al. Seroprevalence of antibodies to SARS-CoV-2 in 10 sites in the United States, March 23 – May 12, 2020. JAMA Intern Med. 2020. doi: 10.1001/jamainternmed.2020.4130
  2. Lvov DC, Alkhovsky SV, Kolobukhina LV, Burtseva EI. Etiology of the COVID-19 epidemic outbreak in Wuhan (Hubei Province, People’s Republic of China) associated with the 2019-nCoV virus (Nidovirales, Coronaviridae, Coronavirinae, Betacoronavirus, subgenus Sarbecovirus): lessons from the SARS-CoV epidemic. Questions Virology. 2020;65(1):5–15. (In Russ). doi: 10.36233/0507-4088-2020-65-1-6-15
  3. Sit TH, Brackman CJ, Ip SM, et al. Infection of dogs with SARS-CoV-2. Nature. 2020;586(7831):776–778. doi: 10.1038/s41586-020-2334-5
  4. Halfmann PJ, Hatta M, Chiba S, et al. Transmission of SARS-CoV-2 in domestic cats. N Engl J Med. 2020;383(6):592–594. doi: 10.1056/NEJMc2013400
  5. Shi J, Wen Z, Zhong G, et al. Susceptibility of ferrets, cats, dogs, and other domesticated animals to SARS-coronavirus 2. Science. 2020;368(6494):1016–1020. doi: 10.1126/science.abb7015
  6. Munnink BB, Sikkema RS, Nieuwenhuijse DF, et al. Transmission of SARS-CoV-2 on mink farms between humans and mink and back to humans. Science. 2021;371(6525):172–177. doi: 10.1126/science.abe5901
  7. Shen Y, Li C, Dong H, et al. Community outbreak investigation of SARS-CoV-2 transmission among bus riders in Eastern China. JAMA Intern Med. 2020;180(12):1665–1671. doi: 10.1001/jamainternmed.2020.5225
  8. Cheng HY, Jian SW, Liu DP, et al. Contact tracing assessment of COVID-19 transmission dynamics in Taiwan and risk at different exposure periods before and after symptom onset. JAMA Intern Med. 2020;180(9):1156–1163. doi: 10.1001/jamainternmed.2020.2020
  9. Zheng S, Fan J, Yu F, et al. Viral load dynamics and disease severity in patients infected with SARS-CoV-2 in Zhejiang province, China, January-March 2020: retrospective cohort study. BMJ. 2020;369:m1443. doi: 10.1136/bmj.m1443
  10. Wölfel R, Corman VM, Guggemos W, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020;581(7809):465–469. doi: 10.1038/s41586-020-2196-x
  11. Fontana LM, Villamagna AH, Sikka MK, McGregor JC. Understanding viral shedding of severe acute respiratory coronavirus virus 2 (SARS-CoV-2): Review of current literature. Infect Control Hosp Epidemiol. 2021;42(6):659–668. doi: 10.1017/ice.2020.1273
  12. Perera RA, Tso E, Tsang OT, et al. SARS-CoV-2 virus culture and subgenomic RNA for respiratory specimens from patients with mild coronavirus disease. Emerg Infect Dis. 2020;26(11):2701–2704. doi: 10.3201/eid2611.203219
  13. Avanzato VA, Matson MJ, Seifert SN, et al. Case study: prolonged infectious SARS-CoV-2 shedding from an asymptomatic immunocompromised individual with Cancer. Cell. 2020;183(7): 1901–1912.e9. doi: 10.1016/j.cell.2020.10.049
  14. Choi B, Choudhary MC, Regan J, et al. Persistence and evolution of SARS-CoV-2 in an immunocompromised host. N Engl J Med. 2020;383(23):2291–2293. doi: 10.1056/NEJMc2031364
  15. Xiao F, Sun J, Xu Y, et al. Infectious SARS-CoV-2 in feces of patient with severe COVID-19. Emerg Infect Dis. 2020;26(8): 1920–1922. doi: 10.3201/eid2608.200681
  16. Meyerowitz EA, Richterman A, Gandhi RT, Sax PE. Transmission of SARS-CoV-2: a review of viral, host, and environmental factors. Ann Intern Med. 2021;174(1):69–79. doi: 10.7326/M20-5008
  17. Yu P, Zhu J, Zhang Z, Han Y. A familial cluster of infection associated with the 2019 novel coronavirus indicating possible person-to-person transmission during the incubation period. J Infect Dis. 2020;221(11):1757–1761. doi: 10.1093/infdis/jiaa07
  18. Bai Y, Yao L, Wei T, et al. Presumed asymptomatic carrier transmission of COVID-19. JAMA. 2020;323(14):1406–1407. doi: 10.1001/jama.2020.2565
  19. Wang Y, He Y, Tong J, et al. Characterization of an asymptomatic cohort of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected individuals outside of Wuhan, China. Clin Infect Dis. 2020;71(16):2132–2138. doi: 10.1093/cid/ciaa629
  20. Arons MM, Hatfield KM, Reddy SC, et al. Presymptomatic SARS-CoV-2 infections and transmission in a skilled nursing facility. N Engl J Med. 2020;382(22):2081–2090. doi: 10.1056/NEJMoa2008457
  21. Lee S, Kim T, Lee E, et al. Clinical course and molecular viral shedding among asymptomatic and symptomatic patients with SARS-CoV-2 infection in a community treatment center in the Republic of Korea. JAMA Intern Med. 2020;180(11):1447–1452. doi: 10.1001/jamainternmed.2020.3862
  22. Madewell ZJ, Yang Y, Longini IM, et al. Household transmission of SARS-CoV-2: a systematic review and meta-analysis. JAMA Netw Open. 2020;3(12):e2031756. doi: 10.1001/jamanetworkopen.2020.31756
  23. Li F, Li YY, Liu MJ, et al. Household transmission of SARS-CoV-2 and risk factors for susceptibility and infectivity in Wuhan: a retrospective observational study. Lancet Infect Dis. 2021;21(5): 617–628. doi: 10.1016/S1473-3099(20)30981-6
  24. Plucinski MM, Wallace M, Uehara A, et al. Coronavirus Disease 2019 (COVID-19) in Americans aboard the diamond princess cruise ship. Clin Infect Dis. 2021;72(10):e448–e457. doi: 10.1093/cid/ciaa1180
  25. Sayampanathan AA, Heng CS, Pin PH, et al. Infectivity of asymptomatic versus symptomatic COVID-19. Lancet. 2021; 397(10269):93–94. doi: 10.1016/S0140-6736(20)32651-9
  26. Zou L, Ruan F, Huang M, et al. SARS-CoV-2 viral load in upper respiratory specimens of infected patients. N Engl J Med. 2020;382(12):1177–1179. doi: 10.1056/NEJMc2001737
  27. To KK, Tsang OT, Leung WS, et al. Temporal profiles of viral load in posterior oropharyngeal saliva samples and serum antibody responses during infection by SARS-CoV-2: an observational cohort study. Lancet Infect Dis. 2020;20(5):565–574. doi: 10.1016/S1473-3099(20)30196-1
  28. He X, Lau EH, Wu P, et al. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nat Med. 2020;26(5):672–675. doi: 10.1038/s41591-020-0869-5
  29. Johansson MA, Quandelacy TM, Kada S, et al. SARS-CoV-2 transmission from people without COVID-19 symptoms. JAMA Netw Open. 2021;4(1):e2035057. doi: 10.1001/jamanetworkopen.2020.35057
  30. Lu J, Gu J, Li K, et al. COVID-19 Outbreak associated with air conditioning in restaurant, Guangzhou, China, 2020. Emerg Infect Dis. 2020;26(7):1628–1631. doi: 10.3201/eid2607.200764
  31. Hamner L, Dubbel P, Capron I, et al. High SARS-CoV-2 attack rate following exposure at a choir practice ― skagit county, Washington, March 2020. MMWR Morb Mortal Wkly Rep. 2020;69(19):606–610. doi: 10.15585/mmwr.mm6919e6
  32. Bahl P, Doolan C, de Silva C, et al. Airborne or droplet precautions for health workers treating COVID-19? J Infect Dis. 2020;jiaa189. doi: 10.1093/infdis/jiaa189
  33. Marks M, Millat-Martinez P, Ouchi D, et al. Transmission of COVID-19 in 282 clusters in Catalonia, Spain: a cohort study. Lancet Infect Dis. 2021;21(5):629–636. doi: 10.1016/S1473-3099(20)30985-3
  34. Cevik M, Marcus JL, Buckee C, Smith TC. Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) transmission dynamics should inform policy. Clin Infect Dis. 2021;73(Suppl 2):S170–S176. doi: 10.1093/cid/ciaa1442
  35. Fung HF, Martinez L, Alarid-Escudero F, et al. The household secondary attack rate of severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2): a rapid review. Clin Infect Dis. 2021; 73(Suppl 2):S138–S145. doi: 10.1093/cid/ciaa1558
  36. Chu VT, Yousaf AR, Chang K, et al. Household transmission of SARS-CoV-2 from children and adolescents. N Engl J Med. 2021;385(10):954–956. doi: 10.1056/NEJMc2031915
  37. Khanh NC, Thai PQ, Quach HL, et al. Transmission of SARS-CoV-2 during long-haul flight. Emerg Infect Dis. 2020;26(11):2617–2624. doi: 10.3201/eid2611.203299
  38. Mahale P, Rothfuss C, Bly S, et al. Multiple COVID-19 outbreaks linked to a wedding reception in rural maine ― August 7 – September 14, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(45):1686–1690. doi: 10.15585/mmwr.mm6945a5
  39. Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA. 2020;323(11):1061–1069. doi: 10.1001/jama.2020.1585
  40. Saloner B, Parish K, Ward JA, et al. COVID-19 cases and deaths in federal and state prisons. JAMA. 2020;324(6):602–603. doi: 10.1001/jama.2020.12528
  41. Wilson E, Donovan CV, Campbell M, et al. Multiple COVID-19 clusters on a university campus ― North Carolina, August 2020. MMWR Morb Mortal Wkly Rep. 2020;69(39):1416–1418. doi: 10.15585/mmwr.mm6939e3
  42. Tenforde MW, Fisher KA, Patel MM. Identifying COVID-19 risk through observational studies to inform control measures. JAMA. 2021;325(14):1464–1465. doi: 10.1001/jama.2021.1995
  43. Klompas M, Baker MA, Rhee C. Airborne transmission of SARS-CoV-2: theoretical considerations and available evidence. JAMA. 2020; 324(5):441–442. doi: 10.1001/jama.2020.12458
  44. Santarpia JL, Rivera DN, Herrera VL, et al. Aerosol and surface contamination of SARS-CoV-2 observed in quarantine and isolation care. Sci Rep. 2020;10(1):12732. doi: 10.1038/s41598-020-69286-3
  45. Ong SW, Tan YK, Chia PY, et al. Air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) from a symptomatic patient. JAMA. 2020;323(16):1610–1612. doi: 10.1001/jama.2020.3227
  46. Kang M, Wei J, Yuan J, et al. Probable evidence of fecal aerosol transmission of SARS-CoV-2 in a high-rise building. Ann Intern Med. 2020;173(12):974–980. doi: 10.7326/M20-0928
  47. Wang W, Xu Y, Gao R, et al. Detection of SARS-CoV-2 in different types of clinical specimens. JAMA. 2020;323(18):1843–1844. doi: 10.1001/jama.2020.3786
  48. Yung CF, Kam KQ, Wong MS, et al. Environment and personal protective equipment tests for SARS-CoV-2 in the Isolation room of an infant with infection. Ann Intern Med. 2020;173(3):240–242. doi: 10.7326/M20-0942
  49. Rabenau HF, Cinatl J, Morgenstern B, et al. Stability and inactivation of SARS coronavirus. Med Microbiol Immunol. 2005;194(1-2):1–6. doi: 10.1007/s00430-004-0219-0
  50. Otter JA, Donskey C, Yezli S, et al. Transmission of SARS and MERS coronaviruses and influenza virus in healthcare settings: the possible role of dry surface contamination. J Hosp Infect. 2016; 92(3):235–250. doi: 10.1016/j.jhin.2015.08.027
  51. Report of the WHO-China Joint Mission on Coronavirus DIsease 2019 (COVID-2019). February 16-24, 2020. Available from: http://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf. Accessed: March 04, 2020.
  52. Chen W, Lan Y, Yuan X, et al. Detectable 2019-nCoV viral RNA in blood is a strong indicator for the further clinical severity. Emerg Microbes Infect. 2020;9(1):469–473. doi: 10.1080/22221751.2020.1732837
  53. Kirtsman M, Diambomba Y, Poutanen SM, et al. Probable congenital SARS-CoV-2 infection in a neonate born to a woman with active SARS-CoV-2 infection. CMAJ. 2020;192(24):E647–E650. doi: 10.1503/cmaj.200821
  54. Vivanti AJ, Vauloup-Fellous C, Prevot S, et al. Transplacental transmission of SARS-CoV-2 infection. Nat Commun. 2020;11(1):3572. doi: 10.1038/s41467-020-17436-6
  55. Kotlyar AM, Grechukhina O, Chen A, et al. Vertical transmission of coronavirus disease 2019: a systematic review and meta-analysis. Am J Obstet Gynecol. 2021;224(1):35–53.e3. doi: 10.1016/j.ajog.2020.07.049
  56. Woodworth KR, Olsen EO, Neelam V, et al. Birth and infant outcomes following laboratory-confirmed SARS-CoV-2 infection in pregnancy — SET-NET, 16 Jurisdictions, March 29 – October 14, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(44):1635–1640. doi: 10.15585/mmwr.mm6944e2
  57. Edlow AG, Li JZ, Collier AY, et al. Assessment of maternal and neonatal SARS-CoV-2 viral load, transplacental antibody transfer, and placental pathology in pregnancies during the COVID-19 pandemic. JAMA Netw Open. 2020;3(12):e2030455. doi: 10.1001/jamanetworkopen.2020.30455
  58. Pique-Regi R, Romero R, Tarca AL, et al. Does the human placenta express the canonical cell entry mediators for SARS-CoV-2? Elife. 2020;9:e58716. doi: 10.7554/eLife.58716
  59. Hecht JL, Quade B, Deshpande V, et al. SARS-CoV-2 can infect the placenta and is not associated with specific placental histopathology: a series of 19 placentas from COVID-19-positive mothers. Mod Pathol. 2020;33(11):2092–2103. doi: 10.1038/s41379-020-0639-4
  60. WHO scientific brief. Definition and categorization of the timing of mother-to-child transmission of SARS-CoV-2. February 8, 2021. Available from: https://www.who.int/publications/i/item/WHO-2019-nCoV-mother-to-child-transmission-2021.1. Accessed: February 11, 2021.

Supplementary files

Supplementary Files
Action
1. JATS XML
Download

Copyright (c) 2021 Eco-vector


СМИ зарегистрировано Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор).
Регистрационный номер и дата принятия решения о регистрации СМИ: № 014448 от 08.02.1996. 
СМИ зарегистрировано Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор).
Регистрационный номер и дата принятия решения о регистрации СМИ: серия ЭЛ № ФС 77 - 80652 от 15.03.2021 .


This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies