Initial infection
The clinical features were as follows: severe sore throat with excessive cough for two weeks that was initially dry but wet and purulent at the end. Sneezing, malaise, fatigue, diarrhoea were also present. Oxygenation saturations was normal as indicated by normal SPO2 more than 96%. The results of the rapid methods showed that the initial infection resulted from a SARS CoV-2 variant, which have had N501 wildtype and D614G mutant. The viral load was Ct value= 17.14. The sequencing result also confirmed amino acids N501 wildtype, A570 wildtype, D614G mutant in the initial variant (MW897351). Treatment was Vitamin D, Zinc, Vitamin C, Paracetamol and Azithromycin for 10 days. PCR result was negative after 2 weeks. Another PCR test was performed 4 months later.
Reinfection
The clinical features were as follows: moderate sore throat with mild coughs for 10 days. Dry mouth was much more than the initial infection. Malaise and fatigue were less prominent than the previous infection, and the patient had no diarrhoea. He had normal SPO2. The rapid methods and sequencing result (MW897356) found two amino acid changes N501Y, and A570D, in addition to the D614G which was also present in the initial infection. Presence of Y510, D570 and G614 mutations in the reinfection suggested the UK variant. Other parameters are as follows: Ct value= 17.9, normal CBC, ferritin, D dimer, LDH and ESR, but CRP was 15 mg/dl (normal CRP titer less than 5 mg/dl). Treatment was Vitamin D, Zinc, Vitamin C, Paracetamol and Azithromycin for 7 days. The patient recovered with negative PCR after 2 weeks with no clinical signs. Both IgG and IgM were considered as negative results with very low titres, 0.28 and 0.182, respectively.
Application of the rapid molecular biological methods on other re-infections
Seven persons, who were previously positive for SARS CoV-2 from June to September 2020 where no N501Y mutations were present in the region, were tested for reinfections by the same molecular methods as previously mentioned. Results of the rapid methods showed that all the 7 persons were re-infected with a variant having both D614G and N501Y mutations. The patients information and results of reinfections are shown in Table 1. The results revealed that one out of 7 reinfections carried the wildtype N501 variant (Case No.2); these were confirmed by DNA sequencings. While other 6 persons were re-infected with N501Y mutated variants which are present in the UK, South Africa and Brazil variants.
Table 1: SARS CoV-2 reinfection cases confirmed by the rapid methods
Cases
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Initial infections
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Reinfections mutations
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Patients clinical information
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1
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PCR positive
on 10/09/2020
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D614G and N501Y mutations
On 22/04/2021
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Age= 43, male, no comorbidities. First infection: asymptomatic with normal CBC and acute phase parameters. Second infection: severe dry cough, malaise for three weeks. Loss of taste and smell
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2
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D614G and wildtype N501 on 10/07/2020. Sequencings:
MW897353.1
|
D614G and wildtype N501 on 10/02/2021.
Sequencings:
MW897354
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Age=35, female, obese. First infection: was feeling tired, fever, headache for 5 days and loss of taste and smell. Second infection: feeling tired, fever, and headache for 4 days.
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3
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PCR positive on 10/07/2020
|
D614G and N501Y mutations
On 24/04/2021
|
Age=55, male, hypertension, diabetes and obesity. First infection: malaise, fever. Second infection, malaise, hypoglycaemia and diarrhoea.
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4
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PCR positive on 10/07/2020
|
D614G and N501Y mutations
On 24/04/2021
|
Age=26, female, no comorbidities. First and Second infection: fever, tiredness, sore throat, headache, loss of taste and smell.
|
5
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PCR positive on 25/06/2020
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D614G and N501Y mutations
On 26/04/2021
|
Age=41, male, obese. First infection: Myalgia, fever, headache, loss of appetite. High platelet and WBC count. Second infection: Tiredness and headache.
|
6
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PCR positive on 10/07/2020
|
D614G and N501Y mutations
On 26/04/2021
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Age= 54, female, hypertension, diabetes and obesity. First infection: Dry cough, myalgia, fever, head ache, loss of appetite. Second infection: Dry cough, Tiredness and fever.
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7
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PCR positive on 10/07/2020
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D614G and N501Y mutations
On 26/04/2021
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Age= 34, female, Asthma, First and Second infection: malaise, sore throat, headache.
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