key: cord-0797422-m1yhmdqn
authors: Ahmed, Abeera; Sana, Fatima; Ikram, Aamer; Yousaf, Shagufta; Khan, Aysha
title: Re-infection or Relapse of COVID-19 in Health Care workers; case series of 2 Patients from Pakistan
date: 2021-05-08
journal: New Microbes New Infect
DOI: 10.1016/j.nmni.2021.100896
sha: 4c8d7c4eba338c368d8dcda6d53285ec1c256510
doc_id: 797422
cord_uid: m1yhmdqn

During an ongoing pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-Cov-2), main question which has arisen in everyone’s mind is about the immune response that may protects from reinfection. Coronaviruses are known for short term immunity. Their ability of mutations enables them to escape host immunity, thus increasing chances of reinfection. Here we report two cases of reinfection among healthcare workers who presented with symptoms of COVID 19 disease, after 03 months of first infectious course. Such documentations are necessary for epidemiological purposes and also to monitor response of virus on re exposure.

In 2020, the world was doomed under fear with the emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) due to its rapid transmissibility and high mortality [1, 8] . Also there is an extreme consternation about reinfection, as virus immune response assumed to be short lived in recovered patients, and cases of reinfection are being reported with increasing frequency [1, 2] .

Here we report two interesting cases of reinfection among healthcare workers (HCW) who acquired SARS-CoV-2 from hospital settings.

The two healthcare workers of almost similar age bracket with no known comorbids, presented to a medical emergency department on different occasions during this ongoing COVID-19 pandemic. We took informed consent from both the individuals and their confidentiality was maintained by using codes.

The first patient is a Nursing Assistant who presented to medical emergency department on 19th June 20 (12 th day of quarantine after returning from leave following COVID policy by Government of Pakistan), with complaints of arthralgia, generalized weakness, anosmia and ageusia. Patient was tested for SARS-CoV-2 on nasopharyngeal swab by using SARS-CoV-2-R-GENE ® Real-time Polymerase chain reaction (r RT-PCR) assays (Biomerieux, France). These triplex assays can detect N-Gene / RdRp Gene, both specific to SARS-COV2 and E-Gene (generic for Sarbecoviruses) in patient's specimen. His PCR was positive with cycle threshold (CT) value 23.6 and detected both RdRp and N gene. His complete blood picture (CBP) showed mild lymphocytosis with thrombocytopenia along with mildly raised C-reactive Protein (CRP) and J o u r n a l P r e -p r o o f Serum(S) ferritin as shown in Table 1 . However other inflammatory markers with baseline serum chemistry and chest x-ray were unremarkable . He remained afebrile with 98% oxygen saturation (SpO2) during his entire hospital stay and was discharged on 5 th July2020 after his 2 consecutive nasopharyngeal swabs were negative. Patients' total COVID antibody (Ab) tested was performed after 23 days of first course of illness by Electro Chemiluminescence (ECLIA) method on Cobas e-411 which was reactive against nucleocapsid protein (N) and he resumed his duties of Nursing Assistant in COVID ICU. On 1 st Nov 2020, patient again developed fever, sore throat with dry cough, after 2 days his RT-PCR was positive for SARS-CoV-2 with detection of single target, N-gene at CT value 33 with non-reactive COVID Abs. For confirmation, his sample was tested with another diagnostic kit of KHB®RT-PCR(Shanghai Kehua bioengineering, China)which detected ORF ab1 region, N, and E gene with CT value 33, 32 and 33 respectively. He had mild course of disease with mildly raised CRP whereas rest of the findings were noncontributory. Patient was discharged after 07 days and remained asymptomatic during followup.

Our second patient Laboratory Technician presented in similar manner on 25 th August (Aug)20with history of fever and sore throat and no other symptoms, he was tested for SARS-CoV-2 on nasopharyngeal swab using u same triplex assays. His PCR was positive with CT value 30.5 and detected for both RdRp and N gene, remained afebrile with 98% oxygen saturation (SpO2) during his hospital stay and discharged on 7 th September(Sep)2020 after his two consecutive nasopharyngeal swabs resulted negative testing.The patients' total COVID antibody (Ab) test was performed after 23 days of the first course of illness by (ECLIA) method on Cobas e-411 which was reactive. He resumed his duty on 20 th Sep 2020 and was placed on COVID 19 screening center for collection of nasopharyngeal swabs from suspected patients. On 15 th December J o u r n a l P r e -p r o o f 4 (Dec)2020, patient presented with symptoms of sinusitis and his X-ray Paranasal sinuses indicted right sided sinusitis, he was given antibiotic cover with levofloxacin 750 mg OD but his symptoms persisted for 5 days, he was tested for SARS-CoV-2-R-GENE® r RT PCR and found positive with CT values (N-gene=33, RdRp -gene= 34)respectively but his repeat COVID Abs were non-reactive, patient was admitted and his baseline chemistry and other markers were noncontributory and was discharged after 07 days.

Our both patients had shown mild course of diseases with mildly raised CRP whereas rest of the findings were non-contributory (mentioned 

isolation ward /discharged isolation ward discharged Note : inflammatory markers S.Lactate dehydrogenase, procalcitonin ,interleukin 6,D-Dimers along with Liver function test and renal function test were also tested but within normal range .Therefore they are not mentioned in the table.

Discussion: Cases of SARS COV 2 reinfection has been reported globally, here we present two cases of reinfection in HCWs, one reported after 135 days while other after almost 100 days of first episode of COVID 19 disease. This time it seems to be healthcare associated COVID-19 infection, as supported by our patients histories. Our cases are different in certain aspects from previously published reports, as in one study reinfection was reported after 2 months in HCW of 58yrs with severe course of illness and no serological evidence of COVID Ab formation from the previous episode, [3] but as per Centers for Disease Control and Prevention (CDC) in settings of limited genomic testing facility higher suspicion of reinfection to be made only once duration is more than 90days with positive symptoms [4, 5] .Contrary to these regional and international reports, [2, 3] ( United Kingdom strain) identified in people travelled from UK to various parts of Pakistan, whole genomic sequencing of those strains in which Spike protein target (S gene)was not detected from oropharyngeal swabs .In above mentioned studied authors have also mentioned other types of mutations not related to S gene [7, 8] .

Major limitation of our study is non-availability of genomic sequencing facility in our set up. Therefore, it cannot be established whether the later infection reported in first HCW occurs with the same virus or the variant strain. As in his case of reinfection, PCR failed to pick the RdRp gene and there can be a probability of mutations. RdRp mutation reported in Pakistani isolates as the second-most common SARS-CoV-2 variant mentioned by Khan TM et al [9] . Therefore, those patients which are symptomatic and presented with CT-value ≥ 33 on single target detection should be reported cautiously and taken as presumptively positive. Therefore, even after 3 months of first episode, one should take standard, contact and droplet based precautions in a true spirit irrespective of his previous status.

As Pachetti M et al emphasized about the RdRp gene alteration, its mutation rate and role in the emergence of multiple drug resistant phenotypes [10] .This information is not only important in diagnosing a case of reinfection but also helpful in better understanding of the effective diagnostic and therapeutic approach against such variants in future. Serological data is also essential to understand the protection provided by these antibodies.

J o u r n a l P r e -p r o o f improve screening and emphasis on skilled molecular testing with strong clinical and serological correlation, which can aid in establishing accurate statistics of reinfection. This way we can obtain precise data of reinfection/reactivation or secondary response. It is important not only for patient management but also for aid in early response and curtails its transmission of infection

What reinfections mean for COVID-19. The Lancet Infect Dis

Genomic evidence for reinfection with SARS-CoV-2: a case study. The Lancet Infect Dis

Reinfection of COVID-19 in Pakistan: A First Case Report

Definitions for COVID-19 reinfection, relapse and PCR re-positivity

CDC. 2020. Investigative criteria for Suspected Cases of SARS -COV2 Reinfection (ICR

Duration of infectiousness and correlation with RT-PCR cycle threshold values in cases of COVID-19

1.1. 7 in Pakistan

Emergence of SARS-CoV-2 Variant: A wake-up call for Pakistan's overburdened healthcare system

SARS-CoV-2 Genome from the Khyber Pakhtunkhwa Province of Pakistan

Emerging SARS-CoV-2 mutation hot spots include a novel RNA-dependent-RNA polymerase variant

Acknowledgement: We like to thank our medical team for guiding us in these case and also Shamil Khanzada who helped us in proof read of our manuscript.

None to declare.