omicron incubation period cdc

Nausea or vomiting. Detection of SARS-CoV-2 Among Residents and Staff Members of an Independent and Assisted Living Community for Older Adults - Seattle, Washington, 2020. Therefore, isolating for five days may not be enough, even if one is asymptomatic, Weiss said. (16) Both people who have been vaccinated and those who have not been vaccinated can transmit virus. What are the implications for public health practice? The Journal of Maternal-Fetal & Neonatal Medicine. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests. Among the 14 persons who were vaccinated and had received an additional dose, five had received the additional dose <14 days before symptom onset. Association between COVID-19 diagnosis and presenting chief complaint from New York City triage data. The Altmetric Attention Score for a research output provides an indicator of the amount of attention that it has received. Comment submitted successfully, thank you for your feedback. Journal of investigative medicine : the official publication of the American Federation for Clinical Research. MMWR Morb Mortal Wkly Rep. April 1, 2022;71(13):489494. Incidence and clinical phenotype of multisystem inflammatory syndrome in children after infection with the SARS-CoV-2 delta variant by vaccination status: a Danish nationwide prospective cohort study. The incubation period in this study for patients during the BA.5dominant period was markedly shorter than that for patients during the Delta-dominant period; this result is supported by those from previous studies (10,11). The role of antiviral treatment in the COVID-19 pandemic. Overall, the average incubation period of all the variants was 6.57 days, ranging from 1.8 to 18.87 days. The median incubation period was 2-5 days (based on earliest and latest exposure). He says multiple studies have shown that "there's very little, if any, transmission after day 10, regardless of the variant . Accessed December 3, 2021. Sect. part 46.102(l)(2); 21 C.F.R. Omicrons incubation period is about two to four days, which is generally shorter than the previous variants. May 19 2022;386(20):1899-1909. doi:10.1056/NEJMoa2202826, Zambrano LD, Ellington S, Strid P, et al. MMWR Morb Mortal Wkly Rep. Aug 13 2021;70(32):1081-1083. doi:10.15585/mmwr.mm7032e1, National Center for Immunization and Respiratory Diseases (NCIRD), Post-COVID Conditions: Healthcare Providers, Decontamination & Reuse of N95 Respirators, Purchasing N95 Respirators from Another Country, Powered Air Purifying Respirators (PAPRs), U.S. Department of Health & Human Services. Please use the form below to submit correspondence to the authors or contact them at the following address: Tsuyoshi Ogata, Itako Public Health Center of Ibaraki Prefectural Government, Osu1446-1, Itako, Ibaraki, 311-2422, Japan; e-mail: kenkoukikikanri@gmail.plala.or.jp. Omicron symptoms: What we know about illness caused by the new subvariants The mean during the BA.1dominant period was 2.9 (95% CI 2.63.2) days, and the median was 2.7 (95% CI 2.53.0) days. BNT162b2 mRNA Vaccination Against COVID-19 is Associated with Decreased Likelihood of Multisystem Inflammatory Syndrome in U.S. Children Ages 5-18 Years. What is the incubation period for Omicron BA.2 and how many - Diario AS If the pair shared meals on both July 4 and 5, we excluded all data from this pair. The clinical presentation of COVID-19 ranges from asymptomatic to severe illness, and COVID-19 symptoms may change over the course of illness. Shorter incubation period among COVID-19 cases with the BA.1 Omicron variant. Aug 24 2022;75(1):e1165-e1175. Feb 2022;10(2):e18. Fatigue. Classification of Omicron (B.1.1.529): SARS-CoV-2 variant of concern. How long can you spread Omicron? | CNN Omicrons average incubation period doesnt mean that people who dont get symptoms four days after exposure are not infected. We defined patients in the Delta-dominant period as those who had symptom onset during July 23September 14, 2021, and either they or their contacts were confirmed to have L452R-positive SARS-CoV-2. As of November 8, all airlines are required to collect contact information for all inbound passengers to the United States to facilitate aircraft contact investigations and other follow-up of travelers when indicated. SARS-CoV-2 Incubation Period during the Omicron BA.5-Dominant Period in Japan On This Page The Study. The clinical presentation of COVID-19 ranges from asymptomatic to critical illness. May 19 2021;373:n1098. That change was announced in late December, before the height of the omicron peak in the U.S. MMWR Morb Mortal Wkly Rep. Jan 28 2022;71(4):118-124. doi:10.15585/mmwr.mm7104a2, Kwon JH, Tenforde MW, Gaglani M, et al. MMWR Morb Mortal Wkly Rep. Sep 10 2021;70(36):1255-1260. doi:10.15585/mmwr.mm7036e2, Siegel DA, Reses HE, Cool AJ, et al. Cough. Among the cases described in this report, the earliest report of symptom onset was November 15. Nebraska Cases of Omicron Suggest Short Incubation Period and Possibly Milder Disease. Jun 18 2022;399(10343):2263-2264. doi:10.1016/S0140-6736(22)00941-2, Notarte KI, Catahay JA, Velasco JV, et al. The rapid antigen test may help gauge infectiousness: If a person tests positive, they should consider themselves contagious, he added. Study: Omicron Symptomatic Sooner and CDC's New Quarantine - BioSpace We extracted data for 266 infector/infectee pairs who had 1 definite date of SARS-CoV-2 exposure as follows: 122 infectees from 108 infectors during the Omicron BA.5dominant period, 68 infectees from 49 infectors during the BA.1dominant period, and 76 infectees from 51 infectors during the Delta-dominant period. doi:https://doi.org/10.1016/S2352-3026(20)30145-9, Sadiq Z, Rana S, Mahfoud Z, Raoof A. Omicron is swifter still, with an incubation period of roughly three days, according to a recent C.D.C. Apr 19 2021;193(16):E540-e548. This is shorter than with Delta and earlier variants. Omicron and its subvariants have shorter incubation periods, which means it takes less time for symptoms to appear after exposure to the virus. More information is available, Recommendations for Fully Vaccinated People, people who are up to date with their vaccines, Clinical Progression, Management, and Treatment, Alene M, Yismaw L, Assemie MA, Ketema DB, Gietaneh W, Birhan TY. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.. MMWR Morb Mortal Wkly Rep. Feb 4 2022;71(5):177-181. doi:10.15585/mmwr.mm7105e1, Olson SM, Newhams MM, Halasa NB, et al. COVID Incubation Period Has Changed and Chicago's Top Doc Says That's You will be subject to the destination website's privacy policy when you follow the link. Figure. Apr 2021;27(4):626-631. doi:10.1038/s41591-021-01292-y, Daugherty SE, Guo Y, Heath K, et al. Jama. Clinical Characteristics of Multisystem Inflammatory Syndrome in Adults: A Systematic Review. SARS-CoV-2 Incubation Period during the Omicron BA.5Dominant Period in Japan. Genomic sequencing detected variants of concern in Japan from July 19September 13, 2001, as follows: 26,963 cases of B.1.617.2 (Delta), 15,009 cases of B.1.1.7 (Alpha), and 5 cases of other variants (9); the L452R mutation was found mostly in the Delta variant. provided as a service to MMWR readers and do not constitute or imply 2021;4(9):e2126456-e2126456. The CDC's researchers point out that Omicron's incubation period is definitely shorter than the original SARS-CoV-2 (five days or greater) and the Delta variant (four days). A) Transmission period; B) incubation period; C) serial interval. The CDC recently examined what happened to a Nebraska patient who was reportedly infected with the . Cookies used to make website functionality more relevant to you. MMWR Morb Mortal Wkly Rep. Jan 21 2022;71(3):96-102. doi:10.15585/mmwr.mm7103e1, Murthy NC, Zell E, Fast HE, et al. According to earlier CDC guidance, COVID symptoms can appear anywhere from two to 14 days after someone is exposed to the virus. Sep 13 2022;226(5):797-807. doi:10.1093/infdis/jiac118, Parker EPK, Desai S, Marti M, et al. MMWR Morb Mortal Wkly Rep. May 27, 2022 71(21):713717. Late Conditions Diagnosed 1-4 Months Following an Initial Coronavirus Disease 2019 (COVID-19) Encounter: A Matched-Cohort Study Using Inpatient and Outpatient Administrative Data-United States, 1 March-30 June 2020. What We Know About the COVID-19 Omicron Variant - Health Conclusions. If you get infected with the Omicron variant, symptoms may occur within two to four days. Trends in Disease Severity and Health Care Utilization During the Early Omicron Variant Period Compared with Previous SARS-CoV-2 High Transmission Periods - United States, December 2020-January 2022. Jul 16 2020;doi:10.1093/cid/ciaa1012, Kompaniyets L, Pennington AF, Goodman AB, et al. . Waltham, MA: ThermoFisher Scientific; 2021. EClinicalMedicine. doi:10.1136/bmj.m3320, DeSisto CL, Wallace B, Simeone RM, et al. JAMA Network Open. Jul 2021;6:100109. doi:10.1016/j.lanepe.2021.100109, Kim L, Garg S, O'Halloran A, et al. . May 2022;28(5):986-989. doi:10.3201/eid2805.220166, Saelee R, Zell E, Murthy BP, et al. Pediatr Infect Dis J. Apr 1 2022;41(4):315-323. doi:10.1097/inf.0000000000003449, Abrams JY, Belay ED, Godfred-Cato S, et al. A new variant of SARS-CoV-2 (the virus that causes COVID-19), B.1.1.529 (Omicron) (1), was first reported to the World Health Organization (WHO) by South Africa on November 24, 2021. PDF SARS-CoV-2 Incubation Period during the Omicron BA.5- Dominant Period the date of publication. 2021;156(2):185-197. doi:10.1093/ajcp/aqab052, Levi M, Thachil J, Iba T, Levy JH. Cmaj. Is It Safe to Travel During the Holidays As the Omicron - Leisure CDC: Study Finds A Shorter Incubation Period of 3 Days With Omicron, Compared to Delta. Overall, its important to get vaccinated and boosted against COVID-19 to have protection against severe outcomes of the virus. Clin Infect Dis. An unvaccinated person had received no COVID-19 vaccine. Centers for Disease Control and Prevention. Duration of infectiousness and correlation with RT-PCR cycle threshold values in cases of COVID-19, England, January to May 2020. 45 C.F.R. Runny nose. This interagency group focuses on the rapid characterization of emerging variants and actively monitors their potential impact on critical SARS-CoV-2 countermeasures, including vaccines, therapeutics, and diagnostics. Users are referred to the electronic PDF version (https://www.cdc.gov/mmwr) New England Journal of Medicine. Public health departments and laboratories in Arizona, California (including Alameda County, Los Angeles, and San Francisco), Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, (including New York City), Pennsylvania, Texas, Utah, Washington, and Wisconsin. Saving Lives, Protecting People. doi:http://dx.doi.org/10.15585/mmwr.mm7113e1, Pingali C, Meghani M, Razzaghi H, et al. Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data. Weekly / December 17, 2021 / 70(50);1731-1734. Clinical Microbiology and Infection. Mar 2 2022;376:e068632. J Infect Dis. Coronavirus Incubation Period: How Long and When Most Contagious - WebMD The Lancet Haematology. Long-Term Symptoms Among Adults Tested for SARS-CoV-2 - United States, January 2020-April 2021. 2021:n385. MMWR Morb Mortal Wkly Rep. Mar 18 2022;71(11):429-436. doi:10.15585/mmwr.mm7111e2, Delahoy MJ, Ujamaa D, Whitaker M, et al. Omicron Incubation Period: How Long Are You Contagious With COVID An infected person can transmit of SARS-CoV-2 before the onset of symptoms. Efficacy of covid-19 vaccines in immunocompromised patients: systematic review and meta-analysis. Apr 1 2021;4(4):e215298. Pediatr Infect Dis J. Dec 1 2021;40(12):e482-e487. On December 10, 2021, this report was posted online as an MMWR Early Release. Carla M. Delgado is a health and culture writer based in the Philippines. Nov 2020;127(12):1548-1556. doi:10.1111/1471-0528.16403, Siebach MK, Piedimonte G, Ley SH. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page. In part, I think [the incubation period] strongly depends upon the infected human.. The CDC report also found that the incubation period for the omicron variant that is, the amount of time from when a person is infected to when symptoms begin appears to be shorter than . Ogata T, Tanaka H. SARS-CoV-2 Incubation Period during the Omicron BA.5Dominant Period in Japan. Nov 2020;2(4):100246. doi:10.1016/j.ajogmf.2020.100246, Galang RR, Newton SM, Woodworth KR, et al. They help us to know which pages are the most and least popular and see how visitors move around the site. Sep 1 2020;370:m3320. According to the CDC, the incubation period for COVID is between two and 14 days, though the newest guidance from the agency suggests a quarantine of five days for those who are not boosted, but eligible or unvaccinated. The information in this article is current as of the date listed, which means newer information may be available when you read this. (11), Less common presentations of COVID-19 can occur. Second, patient pairs with long incubation periods might be censored during observational periods, and selection bias might result in underestimation. Fourteen (33%) persons reported international travel during the 14 days preceding symptom onset or receipt of a positive test result. Am J Obstet Gynecol MFM. Notes from the Field: SARS-CoV-2 Omicron Variant Infection in 10 Persons Within 90 Days of Previous SARS-CoV-2 Delta Variant Infection - Four States, October 2021-January 2022. Will Omicron Show Up On Rapid COVID Tests? Emerg Infect Dis. The 95th percentile distribution for incubation period was estimated at 4.5 (95% CI 4.14.9) days during the BA.5dominant period, 5.2 (95% CI 4.65.9) days during the BA.1dominant period, and 6.1 (95% CI 5.56.8) days during the Delta-dominant period (Table 1; Figure). The estimated mean incubation period was shorter for patients during the BA.5dominant period than during the Delta-dominant period. Aug 24 2022;75(1):e741-e748. While long COVID, hospitalization, or death is less likely if a person is vaccinated, it is still possible and is not a risk that most of us want to take. BA.2 is a sub-variant of Omicron, which means it is likely that it has a shorter incubation period as well, Oller said. What Is Omicron's Incubation Period? - Verywell Health Symptoms can change over the course of illness and can progress in severity. The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website. Because symptoms may progress quickly, close follow-up is needed, especially for older adults, people with disabilities, people with immunocompromising conditions, and people with medical conditions that place them at greater risk for severe illness or death. * SIG includes representatives from CDC, the National Institutes of Health (NIH), the Food and Drug Administration (FDA), the Biomedical Advanced Research and Development Authority (BARDA), the U.S. Department of Defense (DoD), the U.S. Department of Agriculture (USDA), and the U.S. Department of Health and Human Services (HHS). SARS-CoV-2 Spike Antibody, Dominican Republic, https://www.who.int/en/activities/tracking-SARS-CoV-2-variants, https://www.niid.go.jp/niid/en/2019-ncov-e/11411-covid19-ab94th-en.html, https://www.niid.go.jp/niid/en/2019-ncov-e/2484-idsc/9472-2019-ncov-02-en.html, https://www.pref.ibaraki.jp/1saigai/2019-ncov/shiryouteikyou.html, https://www.pref.ibaraki.jp/hokenfukushi/eiken/kikaku/covid-19_ibarakieiken_kensa.html, https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/0000121431_00333.html, https://www.mhlw.go.jp/content/000968056.pdf, SARS-CoV-2 Incubation Period during the Omicron BA.5Dominant Period in Japan, U.S. Department of Health & Human Services, Ogata T, Tanaka H. SARS-CoV-2 Incubation Period during the Omicron BA.5Dominant Period in Japan. Clin Infect Dis. You will be subject to the destination website's privacy policy when you follow the link. Among these cases of COVID-19 attributed to the Omicron variant, 34 (79%) occurred inpersons whocompleted the primary series of an FDA-authorized or approved COVID-19 vaccine 14 days before symptom onset or receipt of a positive SARS-CoV-2 test result, including 14 who had received an additional or booster dose; five of the 14 persons had received the additional dose <14 days before symptom onset. As of December 8, cases had been reported from across the country; 22 states have reported at least one case (Arizona, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, Pennsylvania, Texas, Utah, Washington, and Wisconsin) (Figure). Accessed December 2, 2021. Diarrhea. For the week ending December 4, the Delta variant accounted for >99.9% of circulating SARS-CoV-2 variants. How long is Omicron's incubation period? How the new strain - Yahoo! . Aug 2020;25(32)doi:10.2807/1560-7917.Es.2020.25.32.2001483, Eyre DW, Taylor D, Purver M, et al. Estimated overall mean incubation periods and means within percentiles for Omicron and Delta variants in study of SARS-CoV-2 incubation period during the Omicron BA.5-dominant period in Japan* *Values are mean no. Hospitalizations Associated with COVID-19 Among Children and Adolescents - COVID-NET, 14 States, March 1, 2020-August 14, 2021. How long is omicron's contagious period? | NewsNation Aug 4 2022;doi:10.1093/cid/ciac637, Levy M, Recher M, Hubert H, et al. doi:10.1001/jamanetworkopen.2021.11182, Feldstein LR, Tenforde MW, Friedman KG, et al. Read our. The Centers for Disease Control and Prevention recently shortened its isolation guideline s, citing evidence that COVID is most contagious 1 to 2 days before someone starts feeling symptoms and 2 to 3 days after. 2022;149(1):e2021053418. Exposure in restaurants has been shown to increase COVID-19 infection risk (14). Dec 23 2021;385(26):2487-2489. doi:10.1056/NEJMc2108120, Rossler A, Riepler L, Bante D, von Laer D, Kimpel J. SARS-CoV-2 Omicron Variant Neutralization in Serum from Vaccinated and Convalescent Persons. According to Japans Infectious Diseases Control Law, public health centers (PHCs) must be notified of all COVID-19 cases and conduct contact tracing (4). doi:10.1001/jamanetworkopen.2021.5298, Hobbs CV, Woodworth K, Young CC, et al. BMJ. The estimated mean incubation period for patients during the BA.5dominant period was 2.6 (95% CI 2.52.8) days, and the median was 2.5 (95% CI 2.32.7) days. Updated Jan. 27, 2023 The omicron subvariant of COVID-19, BA.5, became one of the dominant strains of the virus in the fall of 2022 in the U.S. At that time, it was the most easily spread strain to date and is able to evade immunity from COVID infection and vaccination. The risk of severe COVID-19 increases with increasing age over 40 years and with increasing number of certain, Shortness of breath or difficulty breathing. 2021/11/01/ 2021;27(11):1658-1665. doi:https://doi.org/10.1016/j.cmi.2021.05.040, Chandler CM, Reid MC, Cherian S, Sabath DE, Edlefsen KL. Characteristics and Outcomes of US Children and Adolescents With Multisystem Inflammatory Syndrome in Children (MIS-C) Compared With Severe Acute COVID-19. The decrease in isolation time was largely to decrease the impact and disruption of infection on day-to-day life and allow people to return to work sooner, Oller said. Cookies used to make website functionality more relevant to you. Euro Surveill. Infectees exposed while eating do not normally wear masks and may share longer exposure times, so they might be exposed to a higher viral load than those exposed through conversations while wearing a mask. Frequency, Characteristics and Complications of COVID-19 in Hospitalized Infants. Update on Omicron - World Health Organization No hospitalizations or deaths were reported. The incubation period of Omicron - the period from being infected to getting symptoms - is around three days, with the person often becoming infectious a day or two before symptoms emerge. (12), Several studies have reported ocular symptoms associated with COVID-19 infection, including redness, tearing, dry eye or foreign body sensation, discharge or increased secretions, and eye itching or pain.(13). When am I contagious if infected with omicron? - WTOP News BNT162b2 Protection against the Omicron Variant in Children and Adolescents. Oct 1 2021;4(10):e2128568. Clinical Characteristics and Outcomes of Hospitalized Women Giving Birth With and Without COVID-19. Data from December 2021 suggests that Omicrons average incubation period is around two to four days, which would mean that symptoms may develop faster after exposure compared to other variants. The mean and median incubation periods are usually the quick answers, but its also important to know the shape of the curve to understand how many outliers there are and for how long the period is, Stanley H. Weiss, MD, professor of medicine at the Rutgers New Jersey Medical School and professor of biostatistics and epidemiology at the Rutgers School of Public Health, told Verywell. 2021;73(10):1882-1886. doi:10.1093/cid/ciab234, Kronbichler A, Kresse D, Yoon S, Lee KH, Effenberger M, Shin JI. N Engl J Med. Among people ages 60 and older, the average incubation was 7.43 days. JAMA Netw Open. Hoarse voice. Details are available for 43 cases of COVID-19 attributed to the Omicron variant; 25 (58%) were in persons aged 1839 years (Table). CDC recommends prioritizing case investigation and contact tracing for confirmed COVID-19 cases attributed to the Omicron variant. doi:10.1093/cid/ciab338, Wanga V, Chevinsky JR, Dimitrov LV, et al. COVID-19 Incidence and Death Rates Among Unvaccinated and Fully Vaccinated Adults with and Without Booster Doses During Periods of Delta and Omicron Variant Emergence - 25 U.S. Jurisdictions, April 4-December 25, 2021. 2021/02/01/ 2021;159(2):524-536. doi:https://doi.org/10.1016/j.chest.2020.10.014, Genovese G, Moltrasio C, Berti E, Marzano AV. * International travel within 14 days of symptom onset or, if asymptomatic, first positive SARS-CoV-2 test result. Disparities in First Dose COVID-19 Vaccination Coverage among Children 5-11 Years of Age, United States. Pediatrics. All information these cookies collect is aggregated and therefore anonymous. People with COVID-19 may be asymptomatic or experience one or more of the following symptoms(5): The NIH COVID-19 Treatment Guidelinesgroup SARS-CoV-2 infection into five categories based on severity of illness: Studies have documented infection with SARS-CoV-2 in people who never develop symptoms (asymptomatic presentation) and in people who are asymptomatic when tested but then develop symptoms later (presymptomatic presentation). If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance. Emerg Infect Dis. Implementation of concurrent prevention strategies, including vaccination, masking, improving ventilation, testing, quarantine, and isolation are recommended to slow transmission of SARS-CoV-2, including variants such as Omicron, to protect against severe illness and death from COVID-19. These recommendations, however, are only for asymptomatic and mildly ill people, and the shortening to five days means that a person should be isolated during the period when a person is most infectious.. Jan 27 2022;73:81-93. doi:10.1146/annurev-med-042220-014817, Bhaskaran K, Bacon S, Evans SJ, et al. COVID-19 in Immunocompromised Hosts: What We Know So Far. CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website. Effectiveness of a Third Dose of Pfizer-BioNTech and Moderna Vaccines in Preventing COVID-19 Hospitalization Among Immunocompetent and Immunocompromised Adults - United States, August-December 2021. SARS-CoV-2 setting-specific transmission rates: a systematic review and meta-analysis. The average duration of illness is shorter with Omicron than Delta: five days compared to six. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page. Aug 2021;69(6):1253-1255. doi:10.1136/jim-2021-001853, Roskosky M, Borah BF, DeJonge PM, et al. His interests focus on evaluating data on and responding to epidemics in the Itako PHC jurisdiction and Japan. Delta's incubation period was about four days, . Shorter incubation period among unvaccinated Delta variant coronavirus disease 2019 patients in Japan. The best way to protect yourself and those around you is to get vaccinated, Oller said. For those without symptoms, CDC guidance states they are considered contagious at least two days before their positive test. medRxiv. On December 1, the first case of COVID-19 attributed to the Omicron variant was reported in the United States. SARS-CoV-2 Incubation Period during the Omicron BA.5-Dominant Period in 2022/09/15 2022;doi:10.1007/s00431-022-04600-x, Zimmermann P, Pittet LF, Curtis N. How Common is Long COVID in Children and Adolescents? 2021/12/01/ 2021;80:229-238. doi:https://doi.org/10.1016/j.clinimag.2021.06.039, Kanne JP, Bai H, Bernheim A, et al. DOI: http://dx.doi.org/10.15585/mmwr.mm7050e1external icon. The Lancet Child & Adolescent Health. Scientists around the world are working to rapidly learn more about the Omicron variant to better understand how easily it might be transmitted and the effectiveness of current diagnostic tests, vaccines, and therapeutics against this variant. Jan 15 2021;doi:10.1001/jamainternmed.2020.9241, Matar R, Alrahmani L, Monzer N, et al. Am J Transplant. Estimating the duration of infectiousness is more challenging than measuring incubation periods; one study that measured viral load of Omicron suggested that viral load had diminished by days 10-13, which is in line with our findings ( 6 ). Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website. COVID19 in childhood: Transmission, clinical presentation, complications and risk factors. Epidemiology of Infections with SARS-CoV-2 Omicron BA.2 Variant, Hong Kong, January-March 2022. The mean (+SD) incubation periods were 2.6 (+1.0) days during the BA.5dominant period, 2.9 (+1.3) days during the BA.1dominant period, and 3.7 (+1.6) days during the Delta-dominant period.