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Case Report
Open Access Peer-reviewed

Pregnant Patient with Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy during the Omicron (B.1.1.529) Variant Outbreak: A Successfully Treated Case

Michika Hamada, Youichi Yanagawa , Satomi Tanaka, Hiromichi Ohasaka, Kei Jitsuiki, Kouhei Ishikawa
American Journal of Medical Case Reports. 2022, 10(3), 51-55. DOI: 10.12691/ajmcr-10-3-3
Received February 02, 2022; Revised March 04, 2022; Accepted March 11, 2022

Abstract

A 35-year-old pregnant woman (gestational age, 35 weeks) developed general fatigue, headache, and joint pain following the onset fever, cough, and nasal discharge after the outbreak of the Omicron variant in Japan. The patient had obesity (body mass index, 41), depression and gestational diabetes mellitus, which was treated with insulin. On the 8th day after the onset of initial flu-like symptoms, she was admitted to our hospital because polymerase chain reaction for COVID-19 became positive. Initially, her vital signs were stable without any oxygen demand. On day 11, she required oxygen therapy (4 L/min). Chest computed tomography (CT) showed multiple bilateral centrilobular patch consolidations with several subpleural lesions. As she had multiple risk factors for acute respiratory distress syndrome (ARDS), she underwent emergency cesarean section and immune modulation therapy was initiated. After the operation, her oxygenation deteriorated and she underwent tracheal intubation and mechanical ventilation on day 13. After multimodal therapy, her lung function improved and she was extubated on day 16. After rehabilitation and baby care training, she was discharged on day 27 without sequelae. This is the case of a pregnant woman with severe COVID-19 pneumonia who was successfully treated by emergency cesarean section, intensive immune suppression therapy and mechanical ventilation during the Omicron variant outbreak in Japan. The present case suggests that even pregnant women should receive COVID-19 vaccination to avoid the onset of ARDS, a potentially fatal condition.

1. Introduction

COVID-19 in pregnancy is associated with consistent and substantial increases in severe maternal morbidity and mortality and neonatal complications in comparison to COVID-19 diagnosis were compared. 1 Specifically, women with COVID-19 were found to be at higher risk for preeclampsia/eclampsia, severe infection, intensive care unit admission, maternal mortality, preterm birth, medically indicated preterm birth, severe neonatal morbidity index, and severe perinatal morbidity and mortality index values. 1 In addition to pregnancy, a large number of risk factors for adverse outcomes of COVID-19 have been reported. Patient characteristics that are commonly reported as risk factors for adverse outcomes of COVID-19 include old age, male sex, obesity, diabetes mellitus, cardiovascular disease, hypertension, and active cancer. 2, 3

The earliest known case of Omicron infection in South Africa was diagnosed with COVID-19 on Nov 9, 2021, although it is probable that there were unidentified cases in several countries across the world before then. 4 The Omicron variant has resulted in a significant increase in infections worldwide. While >80% of patients experience mild symptoms, a significant proportion becomes critically ill, including older patients and patients with comorbidities. 5 We were not able to identify any reports about Omicron infection in pregnant women. We herein report the case of a pregnant woman with severe COVID-19 pneumonia treated by emergency Cesarean section, intensive immune suppression therapy and mechanical ventilation during the Omicron variant outbreak in Japan.

2. Case Report

A 35-year-old pregnant woman (gestational age, 35 weeks) developed general fatigue, headache, and joint pain following the onset of fever, cough and nasal discharge after the Omicron variant outbreak in Japan. The patient had obesity (body mass index, 41), depression and gestational diabetes mellitus (GDM), which was treated with insulin. Her family history was no specific. On the 8th day after the onset of flu-like symptoms, she admitted to our hospital because a rapid antigen test and polymerase chain reaction for COVID-19 became positive. Initially, her vital signs were stable without any oxygen demand; thus, she only received insulin injections and underwent body weight control without any drugs for COVID-19. However, on day 11 after the onset of symptoms, her percutaneous saturated oxygen (SPO2) was <90% on room air; thus, she received oxygen by nasal cannula (4 L/minute) and our department was consulted. On examination, her consciousness was clear. Her initial vital signs were as follows: blood pressure, 152/104 mmHg; heart rate, 80 beats per minute (BPM); respiratory rate, 20 breaths per minute; body temperature, 36.8°C. Fetal ultrasound revealed that the heart rate was 150 BPM with temporary deceleration down to 60-70 BPM. Chest computed tomography (CT) showed bilateral multiple centrilobular patch consolidations with several subpleural lesions (Figure 1).

The results of the biochemical analysis on day 11 are shown in Table 1.

As she had multiple risk factors for acute respiratory distress syndrome (ARDS), we decided to provide intensive treatment for COVID-19 infection. Accordingly, she underwent emergency cesarean section under general anesthesia (spinal anesthesia failed because of obesity) after the administration of 1 g of methylprednisolone, 1 g of ceftriaxone and 500 mg of azithromycin. The newborn was delivered safely (body weight, 2059 g; Apgar score, 4/7; pH, 7.207). After Cesarean section, she was extubated and admitted to the intensive care unit with 94% SPO2 under 5 L/minute of oxygen. From day 12, methylprednisolone (1 g/day for 2 days), azithromycin (500 mg/day for 2 days), remdesivir (100 mg/day for 5 days), γ-globulin (5 g/day for 3 days), glycyrrhizin (80 mg/day), and continuous infusion of heparin were initiated. From that night, her SPO2 decreased and her oxygen demand increased. On day 13, she required 12 L per minute of oxygen using a reservoir mask to maintain an SPO2 level of >90% (estimated PaO2/FiO2 was 72), she underwent tracheal intubation and mechanical ventilation. Complete mechanical ventilation with high positive end-expiratory pressure (PEEP) and pressure support ventilation (PSV) using muscle relaxant and sedative resulted in the improvement of the PaO2/FiO2 ratio. The time course of treatments, main blood test results and PaO2/FiO2 are shown in Figure 2.

As she showed temporally developed ARDS, the third and subsequent infusion of remdesivir were cancelled. As her PaO2/FiO2 ratio was maintained at >300 after treatment, even PEEP and PSV were decreased, she was extubated on day 16. From day 17, she could stand and eat food with assistance. From day 19, her SPO2 improved to 98% under room air, and oxygen therapy was ceased. From day 20, she could walk for herself and continuous heparin infusion was ceased. On day 21, chest CT revealed the improvement of lung lesions (Figure 1). On the same day, the results of a lung function test were within the normal limits (forced vital capacity, 91% and forced expiratory volume at 1 second, 99%). After baby care training, she was discharged on day 27 without sequelae. Favorable outcomes of both she and her baby were observed in at a 1-month follow-up.

3. Discussion

This patient was successfully treated by emergency cesarean section, intensive immune suppression therapy, and mechanical ventilation during the outbreak of the Omicron variant in Japan. A PubMed search was undertaken to identify articles using the key words “omicron” and “pregnant” on February 27, 2022. This search did not yield any reports about pregnancy in individuals infected with the Omicron variant.

One of the differences between the Omicron variant in the present case and previous reports on COVID-19 pneumonia was the initial lung CT image. The typical image of COVID-19 pneumonia in patients infected with previous variants was ground-glass opacity lesions that mainly spread in the subpleural area. 6, 7 The main findings in the present case were multiple centrilobular patch consolidations in addition to subpleural lesions. The centrilobular patch consolidations had the typical appearance of non-bacterial community-acquired pneumonia or hypersensitivity pneumonitis. 8, 9 The Omicron variant tends to affect the upper respiratory tract. 10 This affinity for respiratory tract infection may have resulted in the multiple centrilobular lesions in the present case. A Japanese report from National Institute of Infectious Disease (February 10, 2022) also showed multiple centrilobular lesions on chest CT in 4 of 40 cases with confirmed Omicron infection. (https://www.niid.go.jp/niid/ja/2019-ncov/2488-idsc/iasr-news/10961-505p01.html).

Another point of difference between the Omicron variant in the present case and previous cases of COVID-19 pneumonia was the good response to our immune suppression therapy and mechanical ventilation. In cases of COVID-19 pneumonia after the Delta variant outbreak, our immune suppression therapy was not sufficient to obtain survival. 11, 12, 13 While the patient in the present case was young and the Omicron variant is thought to be less severe and to be associated with less mortality in comparison to previous COVID-19 pneumonia variants, both experimentally and clinically. 14, 15, 16 This different background may have contributed to the good response to multimodal therapy, including immune suppression therapy.

The patient in the present case had not received COVID-19 vaccination. COVID-19 vaccination is thought to be safe, even for pregnant women. 17 COVID-19 booster vaccination is thought to preventative measure, even against Omicron variant infection. The present case suggests that even pregnant woman should receive COVID-19 vaccination to avoid the possible onset of ARDS, which is a potentially fatal condition. 18

4. Conclusion

We present the case of severe COVID-19 pneumonia in a pregnant woman who was treated by emergency Cesarean section, intensive immune suppression therapy and mechanical ventilation during the Omicron variant outbreak in Japan. The present patient developed ARDS; however, a favorable outcome was obtained after multimodal therapy, despite the presence of risk factors, including pregnancy, obesity and GDM. The present case suggests that even pregnant woman should receive COVID-19 vaccination to avoid the possible development of ARDS, which can be a fatal condition.

Acknowledgements

This work was supported in part by a Grant-in-Aid for Special Research in Subsidies for ordinary expenses of private schools from The Promotion and Mutual Aid Corporation for Private Schools of Japan.

References

[1]  Villar J, Ariff S, Gunier RB, et al. Maternal and Neonatal Morbidity and Mortality Among Pregnant Women With and Without COVID-19 Infection: The INTERCOVID Multinational Cohort Study. JAMA Pediatr 2021; 175(8): 817-826.
In article      View Article  PubMed
 
[2]  Abu-Farha M, Al-Mulla F, Thanaraj TA, Kavalakatt S, Ali H, Abdul Ghani M, Abubaker J. Impact of Diabetes in Patients Diagnosed With COVID-19. Front Immunol. 2020 Dec 1; 11: 576818.
In article      View Article  PubMed
 
[3]  Booth A, Reed AB, Ponzo S, Yassaee A, Aral M, Plans D, Labrique A, Mohan D. Population risk factors for severe disease and mortality in COVID-19: A global systematic review and meta-analysis. PLoS One. 2021 Mar 4; 16(3): e0247461.
In article      View Article  PubMed
 
[4]  Karim SSA, Karim QA. Omicron SARS-CoV-2 variant: a new chapter in the COVID-19 pandemic. Lancet. 2021 Dec 11; 398(10317): 2126-2128.
In article      View Article
 
[5]  Long B, Carius BM, Chavez S, Liang SY, Brady WJ, Koyfman A, Gottlieb M. Clinical update on COVID-19 for the emergency clinician: Presentation and evaluation. Am J Emerg Med. 2022 Jan 21; 54: 46-57.
In article      View Article  PubMed
 
[6]  Zhao X, Liu B, Yu Y, Wang X, Du Y, Gu J, Wu X. The characteristics and clinical value of chest CT images of novel coronavirus pneumonia. Clin Radiol. 2020 May; 75(5): 335-340.
In article      View Article  PubMed
 
[7]  Lin L, Fu G, Chen S, Tao J, Qian A, Yang Y, Wang M. CT Manifestations of Coronavirus Disease (COVID-19) Pneumonia and Influenza Virus Pneumonia: A Comparative Study. AJR Am J Roentgenol. 2021 Jan; 216(1): 71-79.
In article      View Article  PubMed
 
[8]  Ito I, Ishida T, Togashi K, Niimi A, Koyama H, Ishimori T, Kobayashi H, Mishima M. Differentiation of bacterial and non-bacterial community-acquired pneumonia by thin-section computed tomography. Eur J Radiol. 2009 Dec; 72(3): 388-95.
In article      View Article  PubMed
 
[9]  Hanak V, Golbin JM, Ryu JH. Causes and presenting features in 85 consecutive patients with hypersensitivity pneumonitis. Mayo Clin Proc. 2007 Jul; 82(7): 812-6.
In article      View Article  PubMed
 
[10]  Majeed Z. WHO: Omicron Affects Upper Respiratory Tract, Causes Severe Pneumonia But Mild Symptoms. Republic World Last Updated: 5th January, 2022 11: 32 IST (February 14, 2022) https://www.republicworld.com/world-news/rest-of-the-world-news/who-omicron-affects-upper-respiratory-tract-causes-severe-pneumonia-but-mild-symptoms-articleshow.html.
In article      
 
[11]  Jitsuiki K, Katayama I, Iida T, Nagatomo S, Yanagawa Y. Successful Treatment of Elderly Male With COVID-19 Infection With Severe Acute Respiratory Distress Syndrome Using Multimodal Therapy, Including Immune Modulation Therapy. Cureus. 2020 Dec 31; 12(12): e12402.
In article      View Article
 
[12]  Muramatsu KI, Ishikawa K, Komatsu A, Jitsuiki K, Yanagawa Y. Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy With a Combination of Steroid Pulse and Tocilizumab Followed by a Tapering Dose of Steroid Therapy During the Delta (B.1.617.2) Variant Outbreak: A Successfully Treated Case. Cureus. 2021 Nov 7; 13(11): e19340.
In article      View Article
 
[13]  Hamada M, Jitsuiki K, Ikegami S, Ohsaka H, Yanagawa Y. Acute Respiratory Distress Syndrome Induced by COVID-19 successfully Treated by Multidisciplinary Treatment Including Steroid Pulse Therapy. Am J Med Case Rep. 2021; 9(6): 331-334.
In article      View Article
 
[14]  Shuai H, Chan JF, Hu B, Chai Y, Yuen TT, Yin F, Huang X, Yoon C, Hu JC, Liu H, Shi J, Liu Y, Zhu T, Zhang J, Hou Y, Wang Y, Lu L, Cai JP, Zhang AJ, Zhou J, Yuan S, Brindley MA, Zhang BZ, Huang JD, To KK, Yuen KY, Chu H. Attenuated replication and pathogenicity of SARS-CoV-2 B.1.1.529 Omicron. Nature. 2022 Jan 21.
In article      View Article  PubMed
 
[15]  Modes ME, Directo MP, Melgar M, Johnson LR, Yang H, Chaudhary P, Bartolini S, Kho N, Noble PW, Isonaka S, Chen P. Clinical Characteristics and Outcomes Among Adults Hospitalized with Laboratory-Confirmed SARS-CoV-2 Infection During Periods of B.1.617.2 (Delta) and B.1.1.529 (Omicron) Variant Predominance - One Hospital, California, July 15-September 23, 2021, and December 21, 2021-January 27, 2022. MMWR Morb Mortal Wkly Rep. 2022 Feb 11; 71(6): 217-223.
In article      View Article  PubMed
 
[16]  Wolter N, Jassat W, Walaza S, Welch R, Moultrie H, Groome M, Amoako DG, Everatt J, Bhiman JN, Scheepers C, Tebeila N, Chiwandire N, du Plessis M, Govender N, Ismail A, Glass A, Mlisana K, Stevens W, Treurnicht FK, Makatini Z, Hsiao NY, Parboosing R, Wadula J, Hussey H, Davies MA, Boulle A, von Gottberg A, Cohen C. Early assessment of the clinical severity of the SARS-CoV-2 omicron variant in South Africa: a data linkage study. Lancet. 2022 Jan 29; 399(10323): 437-446.
In article      View Article
 
[17]  Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, Panagiotakopoulos L, Marquez PL, Olson CK, Liu R, Chang KT, Ellington SR, Burkel VK, Smoots AN, Green CJ, Licata C, Zhang BC, Alimchandani M, Mba-Jonas A, Martin SW, Gee JM, Meaney-Delman DM; CDC v-safe COVID-19 Pregnancy Registry Team. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons. N Engl J Med. 2021 Jun 17; 384(24): 2273-2282.
In article      View Article  PubMed
 
[18]  Burki TK. Omicron variant and booster COVID-19 vaccines. Lancet Respir Med. 2022 Feb; 10(2): e17.
In article      View Article
 

Published with license by Science and Education Publishing, Copyright © 2022 Michika Hamada, Youichi Yanagawa, Satomi Tanaka, Hiromichi Ohasaka, Kei Jitsuiki and Kouhei Ishikawa

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

Cite this article:

Normal Style
Michika Hamada, Youichi Yanagawa, Satomi Tanaka, Hiromichi Ohasaka, Kei Jitsuiki, Kouhei Ishikawa. Pregnant Patient with Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy during the Omicron (B.1.1.529) Variant Outbreak: A Successfully Treated Case. American Journal of Medical Case Reports. Vol. 10, No. 3, 2022, pp 51-55. http://pubs.sciepub.com/ajmcr/10/3/3
MLA Style
Hamada, Michika, et al. "Pregnant Patient with Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy during the Omicron (B.1.1.529) Variant Outbreak: A Successfully Treated Case." American Journal of Medical Case Reports 10.3 (2022): 51-55.
APA Style
Hamada, M. , Yanagawa, Y. , Tanaka, S. , Ohasaka, H. , Jitsuiki, K. , & Ishikawa, K. (2022). Pregnant Patient with Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy during the Omicron (B.1.1.529) Variant Outbreak: A Successfully Treated Case. American Journal of Medical Case Reports, 10(3), 51-55.
Chicago Style
Hamada, Michika, Youichi Yanagawa, Satomi Tanaka, Hiromichi Ohasaka, Kei Jitsuiki, and Kouhei Ishikawa. "Pregnant Patient with Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy during the Omicron (B.1.1.529) Variant Outbreak: A Successfully Treated Case." American Journal of Medical Case Reports 10, no. 3 (2022): 51-55.
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  • Figure 1. Chest computed tomography (CT) on days 11 and 21 (CT on day 11 demonstrated bilateral multiple centrilobular patch consolidations with several subpleural lesions. CT on day 21 showed the improvement of multiple consolidation)
  • Figure 2. The time course of intensive treatment (After immune modulation therapy and mechanical ventilation without the prone position, the PaO2/FiO2 ratio smoothly increased. On day 16, the tracheal tube was removed. PaO2/FiO2, ratio of arterial oxygen partial pressure to fractional inspired oxygen; LDH, lactate dehydrogenase; CRP, C-reactive protein.)
[1]  Villar J, Ariff S, Gunier RB, et al. Maternal and Neonatal Morbidity and Mortality Among Pregnant Women With and Without COVID-19 Infection: The INTERCOVID Multinational Cohort Study. JAMA Pediatr 2021; 175(8): 817-826.
In article      View Article  PubMed
 
[2]  Abu-Farha M, Al-Mulla F, Thanaraj TA, Kavalakatt S, Ali H, Abdul Ghani M, Abubaker J. Impact of Diabetes in Patients Diagnosed With COVID-19. Front Immunol. 2020 Dec 1; 11: 576818.
In article      View Article  PubMed
 
[3]  Booth A, Reed AB, Ponzo S, Yassaee A, Aral M, Plans D, Labrique A, Mohan D. Population risk factors for severe disease and mortality in COVID-19: A global systematic review and meta-analysis. PLoS One. 2021 Mar 4; 16(3): e0247461.
In article      View Article  PubMed
 
[4]  Karim SSA, Karim QA. Omicron SARS-CoV-2 variant: a new chapter in the COVID-19 pandemic. Lancet. 2021 Dec 11; 398(10317): 2126-2128.
In article      View Article
 
[5]  Long B, Carius BM, Chavez S, Liang SY, Brady WJ, Koyfman A, Gottlieb M. Clinical update on COVID-19 for the emergency clinician: Presentation and evaluation. Am J Emerg Med. 2022 Jan 21; 54: 46-57.
In article      View Article  PubMed
 
[6]  Zhao X, Liu B, Yu Y, Wang X, Du Y, Gu J, Wu X. The characteristics and clinical value of chest CT images of novel coronavirus pneumonia. Clin Radiol. 2020 May; 75(5): 335-340.
In article      View Article  PubMed
 
[7]  Lin L, Fu G, Chen S, Tao J, Qian A, Yang Y, Wang M. CT Manifestations of Coronavirus Disease (COVID-19) Pneumonia and Influenza Virus Pneumonia: A Comparative Study. AJR Am J Roentgenol. 2021 Jan; 216(1): 71-79.
In article      View Article  PubMed
 
[8]  Ito I, Ishida T, Togashi K, Niimi A, Koyama H, Ishimori T, Kobayashi H, Mishima M. Differentiation of bacterial and non-bacterial community-acquired pneumonia by thin-section computed tomography. Eur J Radiol. 2009 Dec; 72(3): 388-95.
In article      View Article  PubMed
 
[9]  Hanak V, Golbin JM, Ryu JH. Causes and presenting features in 85 consecutive patients with hypersensitivity pneumonitis. Mayo Clin Proc. 2007 Jul; 82(7): 812-6.
In article      View Article  PubMed
 
[10]  Majeed Z. WHO: Omicron Affects Upper Respiratory Tract, Causes Severe Pneumonia But Mild Symptoms. Republic World Last Updated: 5th January, 2022 11: 32 IST (February 14, 2022) https://www.republicworld.com/world-news/rest-of-the-world-news/who-omicron-affects-upper-respiratory-tract-causes-severe-pneumonia-but-mild-symptoms-articleshow.html.
In article      
 
[11]  Jitsuiki K, Katayama I, Iida T, Nagatomo S, Yanagawa Y. Successful Treatment of Elderly Male With COVID-19 Infection With Severe Acute Respiratory Distress Syndrome Using Multimodal Therapy, Including Immune Modulation Therapy. Cureus. 2020 Dec 31; 12(12): e12402.
In article      View Article
 
[12]  Muramatsu KI, Ishikawa K, Komatsu A, Jitsuiki K, Yanagawa Y. Severe COVID-19 Pneumonia Treated by Intensive Immune Suppression Therapy With a Combination of Steroid Pulse and Tocilizumab Followed by a Tapering Dose of Steroid Therapy During the Delta (B.1.617.2) Variant Outbreak: A Successfully Treated Case. Cureus. 2021 Nov 7; 13(11): e19340.
In article      View Article
 
[13]  Hamada M, Jitsuiki K, Ikegami S, Ohsaka H, Yanagawa Y. Acute Respiratory Distress Syndrome Induced by COVID-19 successfully Treated by Multidisciplinary Treatment Including Steroid Pulse Therapy. Am J Med Case Rep. 2021; 9(6): 331-334.
In article      View Article
 
[14]  Shuai H, Chan JF, Hu B, Chai Y, Yuen TT, Yin F, Huang X, Yoon C, Hu JC, Liu H, Shi J, Liu Y, Zhu T, Zhang J, Hou Y, Wang Y, Lu L, Cai JP, Zhang AJ, Zhou J, Yuan S, Brindley MA, Zhang BZ, Huang JD, To KK, Yuen KY, Chu H. Attenuated replication and pathogenicity of SARS-CoV-2 B.1.1.529 Omicron. Nature. 2022 Jan 21.
In article      View Article  PubMed
 
[15]  Modes ME, Directo MP, Melgar M, Johnson LR, Yang H, Chaudhary P, Bartolini S, Kho N, Noble PW, Isonaka S, Chen P. Clinical Characteristics and Outcomes Among Adults Hospitalized with Laboratory-Confirmed SARS-CoV-2 Infection During Periods of B.1.617.2 (Delta) and B.1.1.529 (Omicron) Variant Predominance - One Hospital, California, July 15-September 23, 2021, and December 21, 2021-January 27, 2022. MMWR Morb Mortal Wkly Rep. 2022 Feb 11; 71(6): 217-223.
In article      View Article  PubMed
 
[16]  Wolter N, Jassat W, Walaza S, Welch R, Moultrie H, Groome M, Amoako DG, Everatt J, Bhiman JN, Scheepers C, Tebeila N, Chiwandire N, du Plessis M, Govender N, Ismail A, Glass A, Mlisana K, Stevens W, Treurnicht FK, Makatini Z, Hsiao NY, Parboosing R, Wadula J, Hussey H, Davies MA, Boulle A, von Gottberg A, Cohen C. Early assessment of the clinical severity of the SARS-CoV-2 omicron variant in South Africa: a data linkage study. Lancet. 2022 Jan 29; 399(10323): 437-446.
In article      View Article
 
[17]  Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, Panagiotakopoulos L, Marquez PL, Olson CK, Liu R, Chang KT, Ellington SR, Burkel VK, Smoots AN, Green CJ, Licata C, Zhang BC, Alimchandani M, Mba-Jonas A, Martin SW, Gee JM, Meaney-Delman DM; CDC v-safe COVID-19 Pregnancy Registry Team. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons. N Engl J Med. 2021 Jun 17; 384(24): 2273-2282.
In article      View Article  PubMed
 
[18]  Burki TK. Omicron variant and booster COVID-19 vaccines. Lancet Respir Med. 2022 Feb; 10(2): e17.
In article      View Article